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How Paper Cup Manufacturers Are Helping the Environment by Switching Away from Single-Use Plastics

How Paper Cup Manufacturers Are Helping the Environment by Switching Away from Single-Use Plastics

Descripción: How Paper Cup Manufacturers Are Helping the Environment by Switching Away from Single-Use Plastics Single-use plastic cups have always been criticized by organizations that want to tackle the plastic waste in the country. The reason for this criticism is that these cups cannot be recycled and they end up contaminating waste streams. As a result, more waste ends up in landfill. Recognizing the environmental footprint of single-use plastic cups, paper cups manufacturers have begun to switch away from them. They are helping to minimize the environmental footprint by encouraging the use of Paper Cups. Paper Cups Can be Recycled Paper cups are sourced from forests and are a more friendly option than plastics. These cups can be collected separately and trucked to facilities that can recycle them. Some lawmakers and companies argue that paper cups are hard to recycle because they contain a plastic lining that must be separated before the cup can be recycled. This is a totally ridiculous argument. Paper cups be recycled properly if they are collected in special bins and then sent for recycling to the right facility. It is true that cups can end up in landfills if they are thrown into regular bins. However, if consumers properly put them into special recycling bins, they will be recycled by the facilities that possess the ability to remove the plastic lining from paper before recycling the cup. If you often go shopping in shopping malls, you will find that Kraft Bags are widely used in all walks of life. For example, clothing stores and shoe stores we often go to are the most common places to use kraft paper bags. Even when you pack in some fast food restaurants and beverage stores, you will also use kraft paper bags as Takeaway Bags. Compared with plastic bags, the cost of kraft paper bags is higher. Why are so many enterprises willing to use kraft paper bags? One of the reasons is that more enterprises attach importance to environmental protection and regard environmental protection as a part of corporate culture, so they choose more environmentally friendly and renewable paper bags instead of plastic bags. The rise of Insulation Bags in China can be said to have started in 2006, when McDonald's China gradually implemented a kind of kraft paper bag with thermal insulation performance in all stores to hold takeout food, replacing the use of plastic food bags. This move has also received positive response from other businesses, such as Nike, Adidas and other former large consumers of plastic bags have begun to use high-quality kraft paper bags to replace plastic shopping bags. Of course, there are still some people in the market who have different opinions on whether kraft paper is environmentally friendly or not. Generally speaking, people who think kraft paper packaging is not environmentally friendly mainly focus on the manufacturing process of kraft paper and the selection of raw materials. They believe that the pulp of paper packaging is obtained by cutting down trees, causing damage to the ecological environment. The other is the paper in the production process will discharge a large number of sewage, causing water pollution. Through comparison, it is not difficult to see that kraft Paper Bag is better than a plastic bag in environmental protection. Today, more and more attention is paid to environmental protection. An environmental protection kraft paper packaging bag has become the first choice of more and more manufacturers. If you want to contribute to environmental protection, you may as well take the kraft paper bag as the first choice for shopping or food packaging. The automatic Sealing Machine can produce up to 32 vacuum gas flushing MAP containers, 28 vacuum skin packaging or 60 sealed-only trays per minute. It uses 304 stainless steel washing structure and tool-free disassembly of the vacuum chamber. The machine can handle film widths up to 18.75 inches and tray depths up to 4.3 inches. Film sealing, as well as MAP and vacuum skin packaging, can be achieved on the same sealing head. Options include aisle dividers, extended feeders with integrated automatic tray separators, filling and placement systems, cover applicators, aisle merging systems, and seal head storage carts. A total of 21,000 cups were available to the 25,000 fans in attendance, offered as a sustainable alternative to single-use plastics in the live event space. According to Ball, 93% of Plastic Cups used each year end up in landfill, whereas its cups, it says, are recycled and returned to market in approximately 60 days. According to research conducted by the corporation, 73% of consumers would opt for environmentally friendly containers if given the choice, with half willing to pay a premium. Ball Aluminium Cups have been designed to meet this growing demand for sustainable packaging.

Fecha de Publicación: 05-11-21

Wood Crafts

Wood Crafts

Descripción: Wood Crafts Wooden Crafts are the artistic practice of shaping and decorating wooden objects. India is famous for wooden handicrafts. Skilled craftsmen of each state create handicrafts using wood that is available locally. The most common varieties used to make Indian handicrafts are teak, sheesham, sal, oak, mango, ebony and mahogany. Sandalwood, rosewood and walnut are the exotic varieties and are expensive and are used in producing fine pieces of furniture and decorative items. There has been a complete revival of the traditional and antique wood craft, owning to its uniqueness and demand in India and abroad. Indian artisans are experimenting with designs to create a blend of traditional and modern woodcraft. Each piece of Indian wooden handicraft is a labor of love, sweat, and patience, which no machine can replicate. Wooden Toys and games are winning mass of quality these days. The wooden toys and games are put up in innovative as well as classical types that are energizing and thought-provoking for everyone to examine their power. A heavy number of attractively fashioned wooden toys and games will offer hours of amusement. They are designed with exquisitely workmanship and paragon for people of all age-groups. Designed with expert workmanship, wooden toys have arrived at immense popularity and are perfect for people of all generation. The most widely playacted wooden toys and games are wooden chess and wooden carrom board. The wooden toys are carefully carved and attractively designed engaging a special place in lots of families. Wooden toys and games are meant for kids and adults both, and are perfect items for gifting purpose. They are handcrafted with extreme care to have an eye-catching visual aspect. They provide durable fun and are designed to germinate coordination and imagery power among children. The most widely played wooden toys and games are wooden chess and carrom-board. In order to make them easier to carry while traveling, they are available in wooden box which makes them excellent for gift items. Festival Wooden Crafts are very popular. Many companies prefer to give away various wooden gift items as corporate gifts as they are durable and elegant. When wooden items are purchased in wholesale from suppliers or exporters, they prove to be very cost effective. In fact, when companies directly deal with the wooden gift manufacturers, they save a lot of money by avoiding the middlemen in suplly chain. However, wooden corporate gifts might be procured on cheap rates, they always look more expensive due to craftsmanship of the artisans as well as because wood itself is considered to be an expensive medium to make craft items. They can be offered on various occasions including retirement , transfer or anniversary etc. They help in encouraging and motivating people who really deserve to be appreciated. It helps in minimizing attrition rate as well as staff turn over. Wooden gift items cam also be customized as per the requirement of various companies. Acrylic Charms are made with a solid, clear acrylic material that can be printed in full color and cut to any shape. Acrylic charms feature a small 0.085” (~2mm) cut hole for creating your own keychains, jewelry and more. These Acrylic Crafts have been a real hit! Acrylic charms consist of either one layer of acrylic board with an epoxy-covered image on top (or on bottom, if you prefer the acrylic layer over the front and epoxy on back), or two layers of board with the image sandwiched in between. The image itself can be one-sided or two sided. Acrylic Rhinestones are so attractive! When we go shopping in department stores or walk on the road, we often see various shapes and sizes of rhinestones on shoes, bags, jewelry, and even displays. The rhinestones are colorful and shiny, and it is difficult to ignore them. Rhinestones are not diamonds; they are a simulation of diamonds. Since diamonds are natural and are formed under high pressure and high-temperature conditions deep in the earth, often taking a long time to form, they are scarce and very expensive. Rhinestones are artificial and have the sparkling, dazzling effect of diamonds. Therefore, when rhinestones could be manufactured in large quantities, people began to use rhinestones as decorations for jewelry, clothing and other accessories. Forty years ago, the sending and receiving of Christmas Greeting Cards were one of the steps in declaring adulthood and establishing one’s own home. Part of becoming an adult was communicating the year’s events to family and friends. In the Christmas letter that went with the card, there was some bragging about the good things in one’s life but it was also a vehicle to let people know about deaths or difficulties. As Christmas became more about persuading consumers to buy, greeting card companies understood this. They grew their sales by offering greater varieties of cards, including boxed sets and charitable cards. Businesses began sending greeting cards to each other as a thank you for the work done together that year.

Fecha de Publicación: 05-11-21

Folding chairs: A comfortable seating option for space-crunched homes

Folding chairs: A comfortable seating option for space-crunched homes

Descripción: Folding chairs: A comfortable seating option for space-crunched homes Folding Chairs are great for small spaces as they can be used for multiple needs. From dining to studying, a comfortable folding chair can be enjoyed anywhere and then tucked away for storage. Sleek folding chairs are a much better option than bulky wooden chairs in a space that is already short on storage. The folding feature also makes the chair easily transferable and portable. Depending on preference, one can choose between different materials for folding chairs, with plastic being one of the most popular material as it proves to be lightweight. Reclining Chair offers a wonderful place to sit and relax and would be perfect next to a pool or on a back deck or patio. This folding chair transitions effortlessly from an upright seated position to reclining one and will provide utmost comfort to the user. This chair features a lightweight yet sturdy powder-coated steel frame. Its double bungee support system runs up one side and down the other, securely connecting the fabric to the frame. The chair offers reliable support and can accommodate up to 198pounds. The chair also features a weather-resistant Textilene fabric that offers comfortable breathability and ensures a comfortable, stay-cool seating surface that will not stick to the skin. Add convenience to your home with this metal chair in black. Featuring a foldable design, this Folding Lounge Chair is easily portable and can be stored with ease when not in use. Ideal for use at breakfast tables or the dining table while hosting guests, this black chair will prove to be a comfortable option for varying needs. The mesh seating and backrest are soft and comfortable and will give a contemporary appeal to your home. This chair has a PP bush attached at the legs that protect the floor from scratches. Summer is finally here. Now that restrictions have eased and the days are warmer, we will all be hoping to spend a bit more time outdoors, whether lounging or enjoying some alfresco dining. And with that comes the need for adequate (and stylish) Garden Furniture. Whether you are planning to have some barbecues and outdoor parties this summer or just wish to be able to lounge around outdoors, there is no denying that outdoor furniture is a must for 2021, especially if you can find some weather-resistant pieces that mean you will not need to drag your indoor furniture inside every time a sudden downpour hits mid-barbecue. Investing in Garden Cart does not have to be just a practical task, however. Take the opportunity to find stylish pieces, building out the aesthetic of your outdoor space and making it somewhere you really do want to spend time. But with that being said, it can be pretty hard to find the right stores and furniture to suit your garden, given just how many options there are to choose from. Thankfully for you, we know just where to look. From tables and chairs, to sun loungers, fire pits, hammocks and sofas, so many of our favourite furniture stores have launched outdoor lines for this year that are perfect for taking your garden to the next level. Whether you only have patio space or are lucky enough to have some green space to work with, these are the best garden furniture retailers to start browsing. Can you leave garden furniture outside? In reality, the whole point of furniture that is specifically for your garden is that you should ideally be able to leave it outdoors during the warmer, sunnier months. Of course, whether or not this is possible does depend on the material of the furniture and its quality, as well as just how durable it is. Some Hammock Chair is designed more for aesthetic purposes and is best suited to keeping indoors and then dragging outside for your next garden party, but plenty, if not the majority, of garden furniture, is more than suitable to leave outdoors. Make sure to read the product information carefully before placing an order to check whether it's weatherproof, rust-resistant or weather resistant, and research the weight of the furniture so that it isn't easily blown over by the wind.

Fecha de Publicación: 05-11-21

Greens Powder: Are there Health Benefits?

Greens Powder: Are there Health Benefits?

Descripción: Greens Powder: Are there Health Benefits? Health Care Material is a dietary supplement that has become a popular way to help people reach their daily recommended intake of vitamins and minerals. The nutrient combination in greens powder is formulated to support your body’s immune system and energy levels while meeting the nutrition requirements for a healthy diet. Ingredients in greens powders vary by brand, but commonly include nutrition from: Leafy greens and seaweed Grasses and other vegetables Antioxidant-rich fruits Probiotics Nutritional extracts and herbs Cosmetics Material is most often mixed into water, smoothies, or juices. While these powders often come with a grassy taste, natural sugar substitutes like stevia extract are added to improve the flavor. These dietary powders are also usually vegan and made from non-genetically-modified and organic products. Nutrition Information Nutrition content in natural powders will vary by brand. On average, a one-tablespoon serving contains: Calories: 45 Protein: 3 grams Carbohydrates: 6 grams Iron: 18% of your daily value Vitamin A: 60% of your daily value Greens powders often include high levels of vitamin C, which has been linked to healthy immune system function, protection against heart disease, and good skin health. Potential Health Benefits Because greens powders are made from dried fruits and vegetables, some important nutritional content like fiber is lost in the process. Greens powders are not a substitute for a well-balanced diet and cannot replace the nutritional benefits you get from consuming whole foods. However, doctors say that greens powder can be a great way to supplement a healthy diet with a boost of extra vitamins and antioxidants. Taking some vitamins in excess can lead to health issues or may interact with certain medications. It’s important to talk to your doctor before adding any nutritional supplements to your diet and choose a reputable brand of greens powder. The nutrients in greens powders can contribute to potential health benefits including: Healthy Blood Pressure Minerals found in Medicinal Material like calcium and potassium are associated with good blood pressure management. In one clinical study, people who took one serving daily of greens powder experienced a decrease in both their systolic and diastolic blood pressure. Immune System Support Greens powders contain high levels of vitamins and minerals associated with maintaining a healthy immune system. Vitamin A has anti-inflammatory properties that enhance immunity. For example, Selenium is found in most greens powders, and is proven to help the immune system fight infection. Chronic Disease Prevention The vitamins found in Feed Additives can reduce your risk of chronic diseases in the long term. Vitamins like C and K are potent antioxidants that fight cell-damaging free radicals. This cell damage is known as oxidation and is linked to the development of chronic diseases like diabetes and heart disease. One study found that a serving of greens powder taken daily reduced cell oxidation in participants by 30%. Eye and Cognitive Health Vitamin K found in leafy greens is associated with numerous health benefits including maintaining healthy blood vessels, lessening the risk of heart problems, and preventing bone loss with aging. Recent studies have also found vitamin K may promote eye health and reduce incidence of age-related dementia.

Fecha de Publicación: 05-11-21

Garden Hoses: What To Know Before You Buy

Garden Hoses: What To Know Before You Buy

Descripción: Garden Hoses: What To Know Before You Buy Garden Hoses: What To Know Before You Buy Hose for gardening don't last forever. When you're in the market for a new one, these tips will help you make an informed purchase. Your garden hose is probably working overtime this summer as you water plants, irrigate a vegetable garden or wash the car. According to hose manufacturer Teknor Apex, a good garden hose will last five to 10 years if properly maintained. A bad garden hose, as most of us have already found out, will waste water, function poorly and cause bouts of frustration. So to keep the kinks out of your relationship with your PVC garden hose, let’s take a look at what to consider before you buy a new one. Garden hoses are used for transporting water over short or long distances. They can be used for watering a plant, washing a car or every other activity where water is needed. Because garden hoses are very widely used, they need to be able to do many different things. Firstly, they of course have to deliver water at your chosen location. But that’s where the simplicity stops, while not all water or application is the same. Are you working with super clean water and want to be 100% sure there is no contamination with the materials of the hose? Then a garden hose with a pvc-free inner layer specially made for this situation will fit your needs. Is storage space limited? Then a spiral hose, reel garden hose or expandable garden hose will come in handy. Are you looking for a drip irrigation system? Then soaker hoses might be the solution. For every application there are different products available specialized for that situation. Read this article to make a jump start into the world of garden hoses. Diameters and lengths When selecting a garden hose there are multiple parameters that will guide you in the right direction. The diameter of the hose is a good starting point. Typical internal sizes are 13mm (1/2"), 19mm (3/4") and 25mm (1"). It’s important to know that a garden hose has an internal and external diameter. If you want to connect the hose to male coupling, the internal diameter is most relevant to you. Also important is the total length of the garden hose, because a too short hose won’t reach to your destination and a too large hose will take up unnecessary space and cause extra pressure drop, which is often not desirable. Materials Mostly, garden hoses are made from multiple materials. Some garden hoses are even made from up to 8 different layers. All these layers are made from a different material. The outer layer has to be strong because it’ll be dragged along concrete and stones. Often PVC is used for this outer layer. The inner layer can be made from many different materials. If the expandable garden hose is suitable for drinking water purposes, often PU food-safe materials are used for the inner layer. All materials used together determine the temperature range, which is often between -20°C and +60°C. Garden hoses can often withstand pressures up to 30/50 bars (435/725 psi). A pressure gauge is placed to monitor the pressure in the system, to learn more about this read our article on pressure gauges for water applications. Reinforcement A garden hose with only an outer layer would twist and distort very easily. With some exceptions, garden hoses have been strengthened. Between the inner and outer layer, a reinforcement is added made of metal, plastic or another type of strong material. This reinforcement ensures the hose is pressure-resistant, well protected against damage, wears less quickly and it will buckle less quickly. Especially for garden hoses, that are used in harsh situations, this is a very important feature. Couplings To connect a garden hose to a spigot, sprinkler or valve you will need couplings. In most cases a garden hose is connected via Gardena-like couplings. These snap-fit couplings exist of two parts. The first part is a threaded fitting (with 3/4" and 1/2" being the standard) and is mounted on the part that you want to connect to the garden hose. The second part is a quick connector, which is mounted to the garden hose. With this snap-fit coupling it is now possible to easily connect the hose to all the parts that are fitted with the hose fitting like spigots, valves, spray nozzles and sprinklers. We’re all working hard to be conscious consumers. At the grocery store, we read labels and say “no” to plastic packaging whenever we can. We choose safe wooden toys for our kids, avoid poisonous cleaning products, and even grow our own organic vegetables. But wait! After all that effort, are we unknowingly spraying that lovely healthful produce with phthalates, BPA, lead and more? A garden products study completed by The Ecology Center looked at 90 different PVC garden water hose and discovered disturbing levels of each of those chemicals. Some of the toxin levels exceeded safe drinking water standards by 20 times or more. We’ve all had to face some hard facts in recent years: it turns out there is no pristine environment anymore, and even those living in isolated wild places face contamination of the air, soil, and groundwater. But we can take steps to stop contributing to the problem in our own backyards with unsafe hoses. Rather than throw up our hands in despair, we can spread awareness about this lesser-known home health hazard. Not all hoses are created equal, and you can change your watering practices to help your hose do its job without spraying neurotoxins and endocrine disruptors. Because let’s face it: our bodies have enough to deal with in our modern environment without adding to their burden. Choose your hose with care If your hose was purchased before 2007, it’s likely to contain lead. The brass fittings can contain up to 8% lead, and lead may be used in pigments and stabilizers. Green and yellow hoses are particularly likely culprits. Hoses bought after 2007 are governed by a labeling law resulting from a California lawsuit, though product testing still found lead in newer hoses. Choose a new hose labeled as “lead-free”. Tip: check marine or RV stores for lead-free hoses marketed for use in boats or motor homes. These hoses, often white or beige with a thin blue stripe, work well as safe garden hoses. Look for the claim: “drinking water safe”. Most vinyl hoses are made from PVC ominously nicknamed “poison plastic”. PVC relies on phthalates to provide flexibility and elasticity, but these chemicals have received lots of bad press. They are endocrine disruptors, causing problems to human reproductive development, and have been linked to liver cancer. Choose natural rubber hoses instead. Food-grade polyurethane is another good option. Choose non-brass fittings, made of stainless steel, nickel, or aluminum. These metals are more likely to be lead-free, and meet drinking water standards. These soaker hoses made from old rubber tires have nickel plating over the brass fittings to reduce the possibility of leaching lead. Read labels carefully, even the small print. Watch out for hoses containing a warning citing California Prop 65, stating “this product contains a chemical known to the State of California to cause cancer and birth defects and other reproductive harm.” It’s worth a few extra dollars to invest in a hose that will help you enjoy years of watering with your mind at ease. Ask the FDA to regulate hose safety. The Safe Chemicals Act and Safe Drinking Water Act

Fecha de Publicación: 05-11-21

5 Important Factors When Buying LED Drivers

5 Important Factors When Buying LED Drivers

Descripción: 5 Important Factors When Buying LED Drivers 5 Important Factors When Buying LED Drivers WILMINGTON, Mass.--(BUSINESS WIRE)--Jul 31, 2017--Osram, a leading global lighting and technology company, today announced its OPTOTRONIC?Dual-Mode Programmable Emergency LED Driver, the market’s first programmable single-driver solution for emergency Solid State Lighting fixtures, which offers the ability to program and customize the light output in both normal and emergency operations.A separate snap-on battery pack with harness, available in slim, linear and compact options, powers emergency lighting in the event of an outage and provides up to 18W in back-up mode. The complete solution reduces the number of components required per emergency luminaire, substantially simplifies in-fixture wiring, and enables OEMs to better tailor their fixtures to application requirements while reducing the number of SKUs they must inventory. Industry’s First Dual-Mode LED Driver with Programmable Emergency Light Levels Offers OEMs Greater Flexibility, Simplifies Manufacturing (Photo: Business Wire) “Emergency lighting luminaires typically require a dedicated emergency driver, a dedicated LED driver and numerous wiring connections, creating a complex manufacturing process and often compatibility issues for OEMs,” said Tom Shottes, Head of Osram Digital Systems, Americas Region. “Osram’s new OPTOTRONIC? Programmable CE Emergency LED Driver combines the emergency and standard LED drivers into one solution, addressing key issues experienced by OEMs. The ability to program and tailor the light output in both standard and emergency mode offers additional value and flexibility in designing emergency lighting fixtures.” The National Fire Protection Association’s code has a minimum requirement of one foot candle of light on the ground for at least 90 minutes to allow people to safely and efficiently exit a building in the event of an emergency. A programmable emergency driver solution enables OEMs to support customers with tailored and optimized emergency led driver accessories, irrespective of the building architecture, space and lighting plans. The lamp inrush current on switching LEDs has become an area of concern in the lighting industry. ‘Inrush current’ of the LED drivers refers to the input current of short duration that flows into the LED driver, during the initial start-up, to charge the capacitors on the input side. Typically, this is a short duration current, whose amplitude is much greater than the operating or steady-state current. The inrush current is due to the EMC filter on the input and bulk capacitor on the boost circuit this is inherent to the LED technology. The figure shows the nature of the inrush current and its peak, IMAX. T50 is the time duration in which the inrush current pulse is equal to 50% of IMAX. It shows an example of inrush current (IMAX) and T50 times for a typical LED driver. If there are a number of LED drivers in an LED Luminaire, and if there are a number of such LED Luminaires on one circuit, the max peak inrush current and it’s duration may be additive. However, it is not an exact mathematical calculation; i.e. for “N” drivers connected in parallel does not equal exact “N” times the inrush current for one driver or N times the T50 time for one driver. It depends on the impedance of each driver and the line impedance. The line impedance has a significant effect on the peak and duration of the inrush current. Transformer type and size, wire size, length of runs, and other devices in the circuit path are a few things that could lead to high impedance. The inrush current and the duration of the LED driver differs from manufacturer to manufacturer and from model to model. As this current duration is very small, sophisticated instruments with very high sampling rates need to be used for exact calculations. The inrush current also depends on the exact moment of switching, during the alternating cycle. For a typical 150W, 0.7A LED driver, Philips Model 9137012116, used in various CREE luminaires, the inrush current is stated as 130Amp for 165 Micro Seconds. It is suggested that up to 7 -10 of these drivers be used / per 20A C curve MCB, however it will depend on the individual circuit impedance. For a typical 220W, 1.05A LED driver, CREE Model LE098X01 used in CREE High Output Edge luminaires, the inrush current is stated as 80 Amp for 1000uS (1mS). It is suggested that up to 6 – 8 of these drivers be used /per 20A C curve MCB, however, it will depend on the individual circuit impedance. A general recommendation is to use C curve circuit breaker with the highest current rating that is allowed by the circuit cable size. The MCB used needs to have sufficient clearing time for the inrush current to clear, without creating the nuisance tripping on power up. This will give protection from a short circuit and prevent overheating of wiring and connections. MCBs operate by tripping open on detection of an overload or short circuit condition. The tripping point relates to the magnitude of electrical energy being passed – and this in turn depends significantly on both the inrush current peak value and its time duration. Accordingly, an MCB could be tripped either by a high peak of short duration, or a lower peak of longer duration. In either case, the objective is to ensure that the MCB trips before passing excessive energy, yet does not trip and cause lighting blackouts, when it does not need to. Please see below, a typical MCB tripping curve showing the amount of time required for a circuit breaker to trip, at a given overcurrent level. These curves differ from manufacturer to manufacturer and from type to type. Typically, the B type MCB curve has the operating range of 3 to 5 In, C type has 5 to 10In and D type has 10-14 In. LED drivers (also known as LED power supplies) are similar to ballasts for fluorescent lamps or transformers for low-voltage bulbs: they provide LEDs with the correct power supply to function and perform at their best. If you read our previous article on whether or not your LED requires a driver, you’ll already know that all LEDs require a driver and that the question you should really be asking is whether or not your LED requires an external driver. You’ll also know that there are two main kinds of external LED drivers, constant-current and constant-voltage, and that the driver you need depends on whether or not your LED light source already includes a constant-current driver within the light (if so, you would need a constant-voltage driver; if not, you need a separate constant-current driver). Now that you’re certain your LED light requires an external driver as well as what type, it's time to narrow down to the specs you need to consider when making a purchasing decision. Here are five factors that will help you make the right selection. First, consider the voltage requirements of your light. If your 4W UL emergency led driver, use a 12-volt driver; if it uses 24 volts, use a 24-volt driver, etc. When choosing a driver for a constant-current LED, you must also consider the LED’s current output, which is measured in amps or milliamps. In short, make sure your driver will achieve power outputs within your light’s specified ranges: consider both voltage and current range for a constant-current driver, and simply voltage range for a constant-voltage driver. Input Voltage / Current Next, consider the voltage supply of the location you’ll be using your light. Your driver must accept the input voltage of the place you’re using your light so it can properly step it down to the right output voltage. Conventional homes supply a standard of 120 volts, and most commercial or industrial enterprises supply 277 volts, though it’s best to check with an electrician if you’re not sure. Most drivers accept a wide range of input voltages. Again, when choosing a driver for a constant-current LED, you must consider the LED’s current input as well. Max Wattage Lastly, consider the wattage requirements of your light. Choose a driver with a max wattage higher than the wattage of your light. Do not pair a driver with a light that exceeds the driver’s maximum wattage or with a light that uses less than 50% of the driver’s maximum wattage. 2. Dimming Both constant-current and constant-voltage LEDs and drivers can be made with a dimming capability, though both must specify that they are dimmable in the product datasheet for that assertion to be made. If the specs don’t mention dimming at all, it is safe to assume that the product is not dimmable, and the same goes for household LEDs with internal drivers. Dimmable external drivers often require an external dimmer or other dimming control devices specified on the product datasheet to work. 3. Safety IP Ratings IP ratings tell users the environmental protection that a driver’s enclosure provides. The first number specifies protection against solid objects, and the second number specifies protection against water elements. For example, according to the chart below, a driver with an IP67 rating is protected against dust and temporary immersion in water. UL Listed Emergency LED Driver, meaning output is considered safe to contact and no major safety protection is required at the LED / luminaire level. There is no risk of fire or electric shock. These drivers operate using less than 60 volts (dry) and 30 volts (wet), less than 5 amps, and less than 100 watts. Although safer, these limitations pose restrictions on the number of LEDs a Class 2 driver can operate. UL Class 1 drivers have output ranges outside UL Class 2 designations. UL Class 1 drivers have a high-voltage output and safety protection is required within the fixture. Although there are less safety precautions, a Class 1 driver can accommodate more LEDs, making it more efficient than a Class 2 driver. 4. Efficiency Another key characteristic to choosing LED drivers is efficiency. Efficiency, expressed as a percentage, tells you how much of the input power the driver can actually use to power the LED. Typical efficiencies are between 80-85%, but UL Class 1 drivers that can operate more LEDs are usually more efficient. 5. Power Factor The last major characteristic to consider is your driver’s power factor. Power factor tells you how much of a real power load the driver puts on the electrical network. The range for power factor is between -1 and 1. The closer to 1 the power factor is, the more efficient the driver is. A conventional standard for power factor is 0.9 or above. If power factor isn’t mentioned in a driver specification, it implies that the device has a low power factor, below 0.9. Still have questions about choosing a driver? Let us know in comment or drop us a line on Facebook, Twitter, LinkedIn, or Pinterest!

Fecha de Publicación: 05-11-21

STAINLESS STEEL CABLE CLEATS – PREVENTING GALVANIC CORROSION OF CABLE FIXINGS

STAINLESS STEEL CABLE CLEATS – PREVENTING GALVANIC CORROSION OF CABLE FIXINGS

Descripción: STAINLESS STEEL CABLE CLEATS – PREVENTING GALVANIC CORROSION OF CABLE FIXINGS STAINLESS STEEL CABLE CLEATS – PREVENTING GALVANIC CORROSION OF CABLE FIXINGS In the following article we provide an evidence based specification case for stainless steel cable cleats where levels of atmospheric corrosion preclude use of other cable fixing materials. One of the most important issues to consider when specifying cable cleats is the risk of material corrosion – not just as a result of the installation environment, but also from other metals which the cable cleat is in contact with. Galvanic corrosion occurs when dissimilar metals are placed in contact with each other in the presence of an electrolyte. There are two factors that affect the rate of galvanic corrosion, the first is the distance between the two metals in the galvanic series. The further apart the two metals are in the galvanic series, the greater the risk of galvanic corrosion – with the metal higher up the list (more anodic) being the one whose rate of corrosion is accelerated. The second factor to consider is the relative surface areas of the different metals. If the more anodic (higher up the list) metal has a smaller surface area than the metal it is in contact with, the difference in surface area causes the rate of corrosion of the anodic metal to increase. Conversely, if the more anodic metal has a much larger surface area than the cathodic metal, it may be sufficient for the effects of galvanic corrosion to be discounted. In terms of cable cleat selection, the surface area of the cleat is generally significantly smaller than the structure it is mounted on. Therefore, if it is made from a metal that is more anodic than its support structure it will be susceptible to galvanic corrosion. Conversely, if the cable cleat is more cathodic than its support structure, there is little risk of galvanic corrosion. Using this criteria, if galvanised ladder is the support structure, and there are no other significant factors, it is safe to use ball lock stainless steel cable tie. However, if the support structure is stainless steel, separation should be provided if aluminium or galvanised cleats are used. Galvanic corrosion is not easily predictable and can be influenced by the type of electrolytes present such as salt water or fresh water containing impurities. In general terms when guarding against galvanic corrosion, the safest course of action is to separate dissimilar metals with polymer separation washers. This separation should be carried out between the cable cleat and its mounting surface and the cleat’s mounting fixing. All Ellis cable cleat products constructed from dissimilar metal are designed in a way that completely avoids bimetallic contact. As a result of this you can be confident that cable cleats will have a service life measured in decades. All Ellis single stainless steel cable cleat are produced from 316L austenitic stainless steel. In general, cable cleats are manufactured from austenitic stainless steel due to its non-magnetic and corrosion resistant properties – the former ensuring the cable cleat will not induce eddy currents or localised heating of the LV-HV cable. Austenitic stainless steel does become a little magnetic as a result of work hardening when processed. This magnetism can barely be detected with a magnet and so is not significant from an eddy current perspective. 304 austenitic stainless steel, often referred to as A2, is one of the most commonly used stainless steels. It has excellent corrosion resistant properties in most circumstances, although is susceptible in atmospheres where chlorides are present, making it unsuitable for use in coastal or marine environments. 316 austenitic stainless steel, often referred to as A4, contains Molybdenum, which provides resistance against chlorides. 316 is often referred to as marine grade stainless steel due to its suitability for use in coastal and offshore applications. If unsure a simple chemical test can determine whether Molybdenum is present and so differentiate between 304 and 316 types of stainless steel. There are many different types of stainless steel, but there are two principal variants when it comes to cable cleats. 304 and 316 stainless steel are available in low carbon variants, namely 304L and 316L. These variants are immune to sensitisation (grain boundary carbide precipitation). Any cable cleat which is manufactured from stainless steel and includes welding in the manufacturing process should be made in a low carbon (L) variant. Should you require any further assistance in the selection or specification of stainless steel cable tie, MV Medium Voltage or HV High Voltage cables please do not hesitate to contact us. The corrosion resistance properties of stainless steel are a result of chromium, which reacts with oxygen and forms a self-healing impervious layer of chromium oxide on the surface of the steel. In most circumstances the chromium oxide layer is extremely durable and helps in resisting galvanic corrosion. However, in certain installation locations, such as railway tunnels, the oxide layer can be continuously penetrated. This occurs due to trains frequently applying their brakes, which releases mild steel dust into the atmosphere that then settles on the stainless steel. If moisture is present, then corrosion occurs at an exaggerated rate. In such circumstances, if regular washing is not feasible, use of aluminium as an alternative to stainless steel products and/or coating processes are strongly recommended. Ellis Patents offers special coatings to suit specific cable installation environments – e.g. our London Underground Approved electrostatic plastic coatings. CABLE CLEAT FIXINGS Closure fixings on cable cleats are fundamental to the loop strength of the cable cleat and its short-circuit withstand capability. All Ellis Patents 316L stainless steel cleats use 316 fixings, which are manufactured to a precise and specific tensile strength. Fixings are sourced directly from approved manufacturers and any fixing on any cleat is directly traceable back to the batch quality records at that manufacturer. GALVANISED STEEL Contracts often require a guarantee regarding the life expectancy of a cleat. If the installation is designed correctly and all other corrosion issues have been considered this is a relatively simple exercise for wing lock stainless steel cable tie. With galvanized steel, life expectancy is determined by the thickness of the zinc coating. The resistance of galvanizing to atmospheric corrosion depends on a protective film that forms on the surface of the zinc. When the newly coated steel is withdrawn from the galvanizing bath, the zinc has a clean, bright, shiny surface. With time a corrosion process occurs which produces a dull grey patina as the surface reacts with oxygen, water and carbon dioxide in the atmosphere. This leads to the formation of a tough, stable, protective layer, which is tightly adherent to the zinc. As the corrosion process is continuous, the thickness of the zinc layer reduces over time and it is the speed of this reduction that is used to accurately predict the life span of the cable cleat. Corrosion Rates for the UK Permission to use the information relating to galvanising was granted by the Galvanizers Association for galvanised steel. If a galvanised steel cable cleat is specified for use in a zone 3 area then the corrosion rate is 1.5 microns (μm) per year. If the contract for this specification states a required life expectancy of 40 years, then the initial galvanising thickness will need to be a minimum of 60 μm in order to meet the required longevity. The international standard governing Cable Cleats used in electrical installations is IEC 61914:2015. In this standard Cable Cleats are defined as “devices designed to provide securing of cables when installed at intervals along the length of the cables”. Simply put, cable cleats are used to secure, fix and route electrical cables in the positions required in an electrical installation. They can consist of single or multiple parts, plastic or metal material and include some sort of provision for securing itself to a surface or structure. Mounting surfaces that may be specified include; ladder, tray, strut, rail, wire and beam. Examples of different types of cleats securing cable to cable ladder can be seen in the image below. Cable cleats should be designed to ensure that cables are fixed, supported and routed in a manner that provides safe operation and reduces the risk of damage or injury in the event of an emergency or accident. Improper clamping of cables can result in loss through unnecessary downtime or even injury and death. They should at a minimum: Be rated for the specified cable OD. Provide a means of securely fixing the cable. Have adequate strength to secure the cable. Prevent excessive cable movement. Avoid chafing and undue stress in the cable. Cleat Selection and How to Specify Cable Cleats If you’re here it’s likely you may have asked yourself ‘which cable cleat should I use for this job?’ Unfortunately the answer frequently is ‘well, it depends!’ More specifically you may be wondering ‘what size cable cleats for 2.5mm SWA?’ or ‘what size cable cleat for 6mm armoured cable?’. The latter questions are much easier to answer and if you scroll to the end of this article you’ll find selection tables for all of our cleats and common cable sizes. Cable Arrangement The cable arrangement/configuration will primarily dictate the type of cleat required. Cable arrangements for 3 phase installations utilising single conductor cables are typically flat spaced, flat touching or trefoil. A parallel or flat arrangement of single core cables can be completed with a range of single or two-part cleats. Whereas a trefoil or quad arrangement would require a trefoil or quad type cleat respectively. Cable Type - The type of cable being used, Single or Multi-core, as well as its Voltage Levels and Construction Low Voltage (LV), Medium Voltage (MV) or High Voltage (HV)} should be considered. Cable Diameter - Knowing the overall diameter of the cable (measurement across the entire cross-section) is essential in ensuring the correct size of cleat is selected. It is also required to calculate the short circuit forces that the cleat may be subjected to, this can be used to determine correct cleat spacings. Performance - A range of factors will dictate the level of performance your installation will require. The size, weight and length of run of the cable also spacing will usually influence whether you require a polymer or metallic cleat. Things such as the support structure material and environmental conditions (corrosion) can also affect your decision of cleat material. Other factors such as project specification may require special provision for performance in the event of a fire. Low Smoke or Zero Halogen options are available along with cast iron in extreme cases. In summary, to correctly select they type of cleat you require you should be looking to obtain the following information; 1. Calculate the system peak fault current. 2. Confirm cable type and arrangement, including the overall diameter and manufacturing tolerance. 3. Confirm the support structure type and material. 4. Consider any other environmental conditions and project specification requirements. 5. Consult with the Remora Sales team who, given your requirements, will advise the most cost effective solution. In the UK the 17th Edition Wiring Regulations (BS7671) provides current ratings and voltage drop values for all these cable configurations. Information is also available on grouping factors and spacing between circuits to achieve thermal independence. A KPMG International survey recently found that 78% of surveyed engineering and construction companies believe building project risks are increasing. Clients are challenging engineers to complete projects at an unprecedented pace to realize the return on investment, and the need for infrastructure development in remote and complex environments is increasing. A study by the G20-backed Global Infrastructure Hub and Oxford Economics estimates that $3.7 trillion will be invested in infrastructure every year to meet global demand. It’s no wonder engineering and construction firms are constantly pushing the competitive edge. To maintain an advantage, it’s paramount to stay at the forefront of safety compliance and best practices. A fundamental move: Specify cable cleats because they assist with electrical system protection. To ensure long-term integrity of electrical infrastructure, follow cable cleat installation standards according to the International Electrotechnical Commission 61914:2015, the most robust standards established globally. Panduit cable cleats ensure cables remain contained in the event of a short circuit fault, minimising disruption and damage to personnel and property. Uniquely engineered for ease of installation in a range of applications and harsh environments, Panduit has the right product to fit your needs while providing on the job productivity, reliability and safety. Panduit’s cable cleat solution is the industry’s first solution that has streamlined the selection process, tested to IEC standards bringing the vision of creating an engineering specifiable products to the EPC and Contractor firms. Panduit’s cable cleats have simple and intuitive design that helps to improve productivity, have industry-unique mounting brackets and installation tools, and are compatible with a variety of ladder racks and cables The rest of this article will explore IEC 61914:2015 standard at a high level outlining the methodology and testing criteria to successfully design and test a Panduit’s cable cleat to meet standard requirements as well as the appropriate methodology to correctly specify a cleat system in the protection against a short circuit fault.

Fecha de Publicación: 05-11-21

BREWING YOUR OWN BEER: WHAT YOU NEED TO GET STARTED

BREWING YOUR OWN BEER: WHAT YOU NEED TO GET STARTED

Descripción: BREWING YOUR OWN BEER: WHAT YOU NEED TO GET STARTED BREWING YOUR OWN BEER: WHAT YOU NEED TO GET STARTED So you want to make your own beer. How hard could it be, right? Really, it’s not that hard, and I’ll have a nice home beer brewing equipment for you soon that outlines every aspect of the process. Before you get all fired up about it, though, let me be the voice of reason and point out that you’re going to have to spend a pretty nice chunk of change before you can even make your first batch. While the actual process of brewing is simple, it is pretty time consuming, and when you first get started, there is quite the long list of equipment and ingredients that first need to be bought. Not all of these are cheap, either, but after your initial investment, the home brewing process is actually much more affordable than buying beer at the store. Let’s take a look at what all you’ll need to get ready to brew. Every single article or guide that I have read is sure to emphasize this one key point: sanitize like a maniac. Every item that will have even the slightest contact with your beer at any phase of the brewing process needs to be as clean as you can get it. You can, of course, use a mixture of bleach and hot water to soak everything, and then rinse everything thoroughly. This can add additional time to the process that you don’t necessarily have to spend. Many sanitizers do not require rinsing and most are on the inexpensive side, costing less than $5 on average and up to $15 for a large container. One package or bottle will last you through many brewing sessions, so they are a fantastic deal. I would definitely make the small investment in a good no-rinse sanitizer if I was planning to brew on a regular basis. I suppose that you could use any old stock pot for making your wort, but I wouldn’t recommend it. First, when you’re boiling your wort (pronounced wert- see my guide to beer for more on that), you will need plenty of extra room to avoid overflowing the pot. Most home beer recipes make five gallons, so you need at least an 8 gallon pot to have enough additional space during the boiling process. This is not your average-size stock pot. Additionally, brew kettles are made specifically for making beer (obviously), which means that they have nice heavy bottoms for even heat distribution. You can also get them with built-in temperature gauges to easily keep an eye on that, which is really important for the step that follows the boil- adding the yeast (if you add it when the wort is too hot, it kills the yeast, and dead yeast=no beer). You can even get a kettle with a built-in spigot, which will come in super handy. These two features cost more, but even a basic kettle will be a bit pricey, with the price climbing upwards for the extra features and larger sizes. Known in the beer fermentation equipment as a carboy, a fermentation vessel is simply the place where the wort and yeast are combined and allowed to sit for several days to turn into beer. Whatever you use for this fermentation process needs to be 100% airtight so that not even one airborne microbe can get in to alter the taste of the batch. Keep in mind also that you will need at least two containers for this part of the process, because you will siphon the beer out of the first fermentation vessel into a second one after a few days (more on that part of the process in my next article). A plastic carboy will run you around $30, which isn’t too bad, and these won’t be nearly as heavy to try to move when they are full of liquid as a thick glass fermenter (also referred to as a fermentor). On the other hand, a good glass carboy will last forever, with proper care and handling, and they start around the same price point. You can get away with buying a simple food-grade plastic bucket for under $20, but I haven’t seen one that has a gasket on the lid to make for a truly air-tight seal, whereas all the better carboys and other actual fermenters will have a gasket. AIR LOCKS During the fermentation process, as the yeast eats up the sugar in the wort, there are two byproducts- alcohol and carbon dioxide. As the CO2 builds up inside the fermentation vessel, you’re going to need a way to release that gas without letting outside air into the container to possibly contaminate your brew. This is where an air lock comes into play. These fit securely into the top or, in some cases, onto the lower side of any vessel made specifically for brewing. The air lock allows all the built-up gas to escape, which will hopefully prevent any explosions from happening. Yes, you read that correctly- explosions. Whenever you have any situation where pressure is building within an enclosed area, explosions can occur, and the fermentation period is no exception. Not using an air lock pretty much guarantees you’ll end up with beer pouring out of a broken carboy, and with them only costing a couple of bucks, there’s no reason not to buy one. LONG-HANDLED SPOON Remember, you’re going to be dealing with at least an 8-gallon brew kettle, so we’re talking about a really long handle on this spoon, an item you’re not likely to have on hand. You’ll use the spoon for stirring during the boiling process, and you will need to be able to reach all the way to the bottom of the pot. You can also lay the spoon horizontally across the top of the kettle, which will help prevent the wort from boiling over. I recommend going with the stainless steel option on this for durability, which only costs a few dollars. HYDROMETER Before I go into what a hydrometer does and why you need one, we need to talk about gravity. No, I’m not talking about the kind of gravity that keeps your feet on the earth. I’m talking about specific gravity, which, according to Wikipedia, is “the ratio of the density of a substance to the density (mass of the same unit volume) of a reference substance,” with the substance being your fermenting beer and the reference substance being water. Specific gravity in beer is important because it’s how you can determine the percentage of alcohol in the final product. When you first start the process, the density of the liquid will be higher, closer to that of plain water. As the yeast in the fermentation vessel consumes the sugar in the malt and converts the liquid into alcohol, the specific gravity inside the container will drop, because alcohol is considerably denser than water. Once the gravity stops dropping, you know that the yeast has finished its work. A hydrometer is a device that measures the specific gravity of your brew, so it’s useful for determining the aforementioned readings. Also, by taking the measurement of the final gravity inside the container and subtracting it from the original gravity of the brew, you can determine the percentage of alcohol your product contains. A hydrometer looks like an oversized, old fashioned, mercury thermometer, and costs around the same amount, so it’s not an expensive tool to buy and is pretty useful to have around. You just don’t want be measuring non-stop during fermentation since you’d be letting air into the container. You can simply measure before putting on the lid or stopper and then again when you siphon the beer filling machine out for the secondary fermentation that I mentioned before. We recommend this one. SIPHONS As I said, at some point you will need to siphon out the liquid from one fermentation vessel to another. In the same place where you attach the air lock to the container, you will need to attach a siphon. Now, once the yeast has done its job, all the dead yeast will settle on the bottom of the container, along with the used up malt and hops. You need to remove the liquid from the container while at the same time getting as little of those bits and pieces as possible. You could always just pick up the ridiculously heavy carboy or bucket and slowly and carefully pour the beer from one container to the other, but you will end up with more of that sediment in the second container, which will result in a hazy final product. You don’t want that. Instead, make sure to purchase a siphon. Alternatively, you can even buy a ported fermenter that has a valve on the side to transfer the liquid, no siphons required. BOTTLES, ETC. Once you finish the brewing and fermenting, you will of course need to bottle up your brew. Invest in a good set of glass bottles that you can use time and time again. Go with brown glass since they will block out the most UV light, which can cause spoilage. To make things easy on yourself, I would also say to buy the bottles with the attached swing caps. Expect an investment of around $2.50 per bottle. The kicker is that you will probably need about 4 packs to bottle all of the beer from a standard recipe, which is for 5 gallons. If you want to save some money here, you can always opt for capping the bottles yourself. You will spend about half the amount on the bottles themselves going that route. You will spend another couple of bucks on a pack of bottle caps and a little more for a bottle capper. This will ultimately result in some savings. And considering the amount of money you will have invested already, this seems like a pretty good idea! INGREDIENT STARTER KITS Assuming you fall in love with the whole home brewing process, at some point you will probably want to buy your own malt and hops to really customize it to your taste. To begin with, though, it will be so much easier for you to buy a recipe kit. There are tons of websites including Amazon that offer these if you don’t have a home brewer’s store in your neck of the woods. Just decide what kind of beer you want to make (ale or lager) and the style that you prefer, and you’ll be able to find a kit for that. This really simplifies the brewing process, which is awesome when you’re a beginner. And they’re affordable, too. READY TO MAKE SOME BEER? I bet you would have never thought that it can take so much stuff to actually make a few bottles of beer, not to mention an initial investment of at least $300. Now that you know, though, it’s easy to set about buying what you need. Stay tuned for my follow-up article where you’ll get a step-by-step guide to the actual beer-making process. Although the equipment needed to brew beer traditionally was fairly simple, large commercial breweries today use equipment that does everything from crack the grain to seal the cases and a multitude of chores in between. These are the basics: Most folks visiting a brewery immediately recognize the large, round brew kettle that usually dominates the brewhouse. Somewhere nearby is usually a second, sometimes smaller, similar-looking vessel called a mash tun, and if the place is big and brews lagers, it has yet another one, called a lauter tun. These vessels are vented through stacks that carry the steam out of the brewhouse, consequently treating the whole neighborhood to the intoxicating, malty-sweet aroma of beer in the making. Traditionally, these vessels were made of copper and were often referred to simply as the coppers. Nowadays, the term has fallen out of use, mostly because modern brewing equipment is fabricated from the relatively cheaper and easier-to-obtain stainless steel. After the first three vessels are used, the wine filling machine is pumped (and cooled at the same time) into a big tank called a fermenter. For sanitation purposes, fermenters are usually airtight vessels that allow only for the escape of the carbon dioxide pressure built up inside. However, some traditionalists in the industry, particularly in Britain and Belgium, still allow their beer to ferment in open vessels, and some even encourage spontaneous fermentations caused by wild, airborne yeast (Belgian Lambic brewers, for example). At this point, each brewery uses different kinds of tanks and does different things to its beer. For example: Most breweries allow beer to go through a short aging process after the initial fermentation, using additional vessels cleverly named aging tanks for this purpose. Next, breweries transfer the aged beer from aging tanks into finishing tanks to prepare them for their introduction into society. Beer would not exist without microbes. During fermentation, yeast cells convert cereal-derived sugars into ethanol and CO2. Yeast also produces a wide array of aroma compounds that influence beer taste and aroma. The complex interaction between all these aroma compounds results in each beer having its own distinctive palette. This article contains all protocols needed to brew beer in a standard lab environment and focuses on the use of yeast in beer brewing. More specifically, it provides protocols for yeast propagation, brewing calculations and, of course, beer brewing. At the end, we have also included protocols for analyses that can be performed on the resulting brew, with a focus on yeast-derived aroma compounds. Beer brewing is intrinsically a biotechnological process: the conversion of raw materials into beer relies on many different enzymatic reactions and microbial activity. Beer is traditionally made from four key ingredients: malted cereals (barley or other), water, hops, and yeast. Each of these ingredients contributes to the final taste and aroma of beer. Beer production starts with the malting of barley (or other cereals, such as wheat, sorghum, rye, or oats). The main goal of malting is to activate enzymes within the grain. These enzymes will hydrolyze starch and other compounds within the kernels during mashing (Goldammer, 2008; Kunze, 2004). During malting, barely kernels are soaked in water and periodically aerated, the so-called steeping and germination phase. During germination, three important groups of enzymes are activated: (i) amylases, (ii) proteases/peptidases, and (iii) beta-glucanases. Each of these enzymes have an important function during the malting and downstream brewing process: (i) amylases convert starch, present in the barley kernels, into fermentable sugars; (ii) proteases and peptidases break down proteins and release free amino nitrogen (FAN), while (iii) beta-glucanases degrade the endosperm cell wall, allowing other enzymes access to the endosperm. Next, in the drying and kilning phase, kernels are dried and heated. This stops germination, arrests enzymatic activity within the kernels, reduces spoilage risks, and determines the impact of malt on the final aroma and color of the beer. The actual brewing process consists of five steps. The main goal is to convert insoluble malt or grain material into a soluble and fermentable extract. Milling of malted grains (i) and mashing (ii) In this step, milled grains are mixed with warm water. This mash is kept at specific temperatures and pH to ensure proper enzymatic conversion of starch and proteins. Traditionally, a starting temperature of 45°C is used. At this temperature, proteases are activated and degrade proteins to short peptides and amino acids, that will form the major nitrogen source for yeast during fermentation. The mash is then heated to 62°C-64°C, at which starch will gelatinize and become accessible to amylases. Beta-amylases will cleave off maltose from starch molecules. The mash is then heated to 72°C for 15-25 min, allowing further breakdown of long chain polysaccharides by alpha-amylases. Finally, the temperature of the mash is raised to 78°C, stopping nearly all enzymatic activity. Modern, highly modified malts allow mashing in directly at temperatures >60°C since the protein breakdown has already been completed by the maltster. Filtering/lautering (iii) During this step, the insoluble fraction (spent grains) is separated from the soluble extract. The remaining extract (wort) is transferred to the boiling vessel. Boiling (iv) During boiling, hops and other spices are added. These contribute to bitterness and aroma of the final beer. More specifically, hops contain alpha acids and during boiling, these acids will isomerize into iso-alpha acids, the major bittering substances in beer. Bitter hops contain high concentrations of alpha acids (6%-16%) and are often added at the beginning of the boil. Aroma hops have a high hop oil content (>1%), which contains 200-250 different compounds that contribute to the characteristic aroma of hops (e.g., myrcene, linalool, and nonenal) (Kunze, 2004). Aroma hops are typically only added towards the end of the boil, or in the dry-hopping of green beer to reduce the stripping of aroma-active compounds. Other major effects of wort boiling include protein denaturation and aggregation, concentration of the wort, stripping of off-flavors such as dimethyl sulfide (DMS), and sanitization of the wort. The boiled wort is then transferred to a whirlpool to remove the aggregated protein and insoluble hop components (hot trub). Finally, the wort is cooled, aerated, and transferred into the fermentor, where yeast is added.

Fecha de Publicación: 05-11-21