Hops are the flowers of a perennial plant scientifically known as Humulus lupulus. They are primarily used as a flavoring and bittering agent in the production of beer. Hops are added to the boiling wort during the brewing process, where their alpha acids are isomerized, creating a bitter taste that balances the sweetness of the malt. The bitterness and aromatic characteristics in hops come from oils and resins (alpha acids) in the female flower of the hop plant. Hops with low alpha acid percentages are generally used to create fine aromas and are added in very late in the brewing stage. Hops with higher alpha acids are viewed as bittering hops and are added very early in the kettle during boiling.
Modern brewers (and consumers) often refer to IBUs (International Bitterness Units) as a measurement of bitterness in beer by measuring the remaining alpha acids after boiling. The scale runs from 0 (no bitterness) to 100 (extremely bitter). Lighter beers will generally measure between 6-17 IBU’s, while North American IPA’s may often achieve IBU’s greater than 60.
While IBUs can provide a general idea of a beer’s bitterness level, they should not be relied on as the sole indicator of a beer’s flavour profile for several reasons. The perception of bitterness varies from person to person, so two people might perceive the same beer as having a different level of bitterness even if it has the same IBU rating. Also, different hop varieties have varying alpha acid levels, which can affect how bitter they make the beer. IBUs do not consider the type of hops used or their flavor and aroma characteristics, which can greatly affect the overall taste of the beer. Other factors such as hop variety, malt sweetness, alcohol content, and carbonation levels can also greatly impact a beer’s perceived bitterness.
Hop flavours and aromas are largely determined by terroir (the impact of soil, water, weather, and sun). Depending on the variety of hops used, the hops can give the beer a wide range of flavors, including citrus, pine, floral, and spicy notes. Brewers choose the type of hop they want based on the beer they are creating.
Hops are typically grown on trellises, which are tall structures as the hop plants grow up to 6 metres and need support to grow upright. They require a lot of sunlight and a well-drained soil that is rich in organic matter. The flowers are typically harvested once a year in the late summer or early fall. The hop cones are picked from the bines and dried in a kiln to preserve them for later use in brewing. The dried hop cones can be used as whole cones or ground into pellets, which are a convenient form for use in brewing. Most of the hops that are used in brewing are bred and grown in the United States, Germany, and the Czech Republic but many other countries including Canada contribute to the overall global hop agriculture.
The backbone of beer is derived from malted grains. Malting is a process where the valuable parts of a cereal grain are awakened and utilized to create flavour, colour, and mouthfeel in beer. The malting process begins with soaking the grains in water for several days. This process (steeping) is designed to replace nature by providing water and oxygen necessary for the grain to grow. After several days, the grain is allowed to grow naturally at controlled temperature and humidity conditions (germination). The final stage in malting is heating the grain to reduce moisture, create colour and flavour and to stabilize the malt.
Many brewers also see barley as the very soul of beer. It is a natural and easy source of soluble starches that are necessary for conversion into sugars for fermentation. During the malting process, enzymes break down the starches in the barley into simple sugars that the yeast can consume, converting them into alcohol and carbon dioxide.
The hard, outer shell is ideal for creating a filter bed during lautering (the step-in brewing designed to create clarity) and the moderate levels of proteins contributing to head retention, the foam that forms on top of the beer after it is poured. The protein in the malt helps stabilize the head and keep it from dissipating too quickly.
In addition, malting barley in Canada represents less than 25% of all the barley grown and is valued as a specialty crop and attracts a premium price for farmers.
Other grains that can also used include wheat, rye, oats, and sorghum. Each of these has benefits but barley continues to be the majority of all grains used in brewing. Even in wheat beer, the proportion of barley is generally over 50%. This is due to the reality that other grains are malted without husks and are difficult to filter by themselves. Canadian brewers purchase more than 300,000 tonnes of Canadian grain a year.
Malt provides a spectrum of colour to beer that ranges from pale straw to black. The level of roasting or toasting of the malt can also impact the beer’s color, flavour, and aroma. Pale malt creates the lighter colour and flavours seen in most easy drinking and thirst-quenching beers while dark malts are responsible for the richer, more robust colours in porters and stouts. A variety of caramel-coloured malts are used to impact colour but more so to create complex flavours and aromas in beer.
Often overlooked, by volume water is the primary ingredient in beer, typically accounting for 92-96% of its packaged volume. The quality of water used in brewing greatly affects the taste and quality of beer.
Different regions have different water profiles, which can influence the flavour of beer brewed locally. For example, hard water with high mineral content (generally calcium and magnesium) can produce a more bitter beer, while soft water with low mineral content can result in a smoother, sweeter beer. Different beer styles may require different types of water to achieve the desired flavour profile.
Soft water allows a beer to gently arrive in the mouth and extends the finish. Hard water, on the other hand, can increase the characteristics of hops, arrive with a distinct sharpness, and exit your mouth quickly.
Brewers carefully consider the water’s chemical composition when selecting their water source and may adjust the water’s profile to achieve the desired flavour characteristics. They consider its minerality, pH levels, consistency, and sanitation. Water used in beer brewing must be free of contaminants and bacteria to prevent spoilage and ensure the beer’s quality and safety.
Burton-upon-Trent in England is renowned as having the hardest brewing water in the world and because of its impact on the creation of Pale Ales and India Pale Ales has also created a unique word for re-mineralization. ‘Burtonization’ is now an accepted term in brewing for the addition of calcium sulphate and magnesium sulphate to brewing water. In Canada, there are many locations with hard water.
This single-celled micro-organism is the engine that creates beer. By adding yeast to a sugar-rich solution called ‘wort’, brew masters can metabolize the malted grain`s fermentable sugars into alcohol and carbon dioxide (carbonation) which are the two main by-products of the fermentation process. Without yeast, there would be no alcohol in beer. It is crucial for the brewer to also supply pure oxygen to the yeast. Yeast requires sugar to digest and oxygen to breathe before it starts to reproduce and provide alcohol.
Most brewing yeasts belong to a family called Saccharomyces. These pure yeast strains are the key to brewing consistent beers. Each of the hundreds of families of yeast has unique characteristics that also help to create flavours and aromas in beer.
There are two main types of yeast used in beer brewing: ale yeast and lager yeast. Ale yeast is a top-fermenting yeast that ferments at warmer temperatures and produces fruity and complex flavours and aromas, while lager yeast is a bottom-fermenting yeast that ferments at cooler temperatures and produces a cleaner, crisper taste.
While many smaller brewers buy their yeast from reputable suppliers, larger brewers propagate their own, proprietary, pure yeast strains.
Modern brewers explore a world of ingredients to add complexity to their beers. Any carbohydrate (other than malt) is considered to be an adjunct in brewing terms. Adjuncts is the term used for any fermentable or non-fermentable ingredient used in beer brewing that is not malted barley, wheat, or rye.
Adjuncts can include a wide variety of ingredients such as corn, rice, and oats as a supplement to malt. The purpose behind these lighter flavoured cereals is to create a beer with a lighter body and softer flavour. This way of brewing is designed to produce light and easy drinking beers.
Ingredients like dried fruit, herbs, and spices have also been used for centuries in brewing to create flavour and aromas. Examples of this include orange, coriander, and unmalted wheat.