218 pplContents:
- Introduction
- Biochemicals in hops
- Processing types
- Quality grades
- Storage techniques
Brewing beer is a complex process implying four main components. The basis of the drink are water, malt, yeast, and hops. The latter plays a particularly important role – it gives rise to the bitterness-leveling excessive malt sweetness and responsible for obtaining a balanced taste in some beers. In addition, hops bring about a special aftertaste and a pronounced aroma that ranges from citrus to herbal, and even earthy. At the same time, it works as a natural preservative that prevents spoilage of beer and contributes to the foam stability.
But hops are not created equal. Like grapes, modern hops differ greatly, their composition and geographical origin affect the characteristics of beverages in one way or another.
Biochemicals in Hops
Hop cones have been used in brewing since ancient times. Basically, these are flowers of common hop resembling a huge liana. It grows in the wild and prefers rain forests. And being cultivated, it grows on trellises on large plantations.
There are female and male cone-shaped inflorescences, but only the former are good for brewing. The key lies in the presence of lipulin glands that produce bitter resins, and these resins become the basis of the hop aroma and flavor. Male flowers do not have this feature.
In addition, hops are highly valued due to the presence of:
- Alpha acids – organic molecules that give beverages that characteristic bitter taste, and act as an antiseptic, preventing bacteria growth. Hops are rich in humulone, adhumulone, and cohumulone.
- Beta acids – have the same function as the alpha substances, but their concentration in the cones is much less. Lupulone, adlupulone and colupulone give the drink a tougher bitterness.
- Oils – substances responsible for the beer aroma. Since they are volatile, they should only be added at the end of brewing process, and sometimes during fermentation. The grassy flavor characteristic of European varieties of the drink is provided by humulene and myrcene, while caryophyllene, on the contrary, fills the beverage with woody and earthy notes, with shades of cloves and pepper.
- Polyphenols – tannins, astringent to taste, designed to bind and precipitate protein compounds.
Processing Types
The ratio of the above components varies from type to type. For convenience, all hops are divided into bittering hops, aroma hops, and dual-purpose hops. The former, such as Nugget, Galena and Magnum, have a huge alpha acids content. The second, also called the finish hops, are saturated with essential oils – for example, Cascade, Amarillo, and Liberty. And Cluster and Eroica are dual-purpose, as they are rich in both substances.
In addition, the plant is classified according to the area of cultivation. Hops, like grapes, absorb everything that surrounds them: terrain, conditions, climate, soil composition, and microbiota. When talking about the geographical origin of hops, we typically name three zones:
- Noble, from the Czech Republic and Germany.
This variety is considered a classic and gives the drink soft, earthy, and spicy notes. It is rich in essential oils. These very hops form the basis of German and Czech pilsners. In Germany, Hallertau is considered the most famous – delicate, with a slight peppery spiciness, and floral tones. The spicy herbal Tettnanger and the pleasant woody Spalt are no less popular. Among Czech hops, Saaz stands out with its persistent earthy spiciness. These are used for brewing Pilsner Urquell and Trumer Pils.
- American, from the USA.
It is used to produce brighter beers with pine, resinous, citrus hints, which has become the hallmark of all IPAs. Famous C-hops include spicy Columbus, grapefruity Cascade, floral Centennial, and soft Chinook. Willamette, with its citrus undertones and an earthy hint, is equally well-known.
- English, from the UK.
It was brought in the 15th century from Flanders and marked by its excellent preservative properties. This hop contains less myrcene and therefore has a complex and delicate aroma. It is usually described as herbaceous, lemony, woody, minty, or tea-like. British beer in general is characterized by a balance of hops and malt, but English IPAs and bitters can serve as an example of how this variety works.
Among the most famous are cedar Fuggle, Challenger with earthy and tea hints and marmalade-like fruit bitterness, Golding with peppery-lemon character. They are used to make Peter's Best Bitter, Abbot Ale, and Timothy Taylor Landlord.
Recently, hops from Australia and New Zealand have also been gaining popularity. They are distinguished by a high content of alpha acids and an expressive lemon flavor. New Zealand variety Nelson Sauvin reminiscent of white wine, and limelike Motueka, which is the younger brother of the Czech Saaz, are also notable. Of the Australian hops, Galaxy hops are valued for their pronounced citrus hue, complemented by passion fruit and peach.
Of course, we shouldn't forget about such trusted types as French Strisselspalt and Slovenian Styrian Goldings. There is also a category of so-called New World hops. It is divided into:
- Citra from the USA, with citrus, pineapple, and lychee notes.
- El Dorado with hints of pineapple, melon, and stone fruits.
- Amarillo with orange character.
- Mosaic with berry and mango accents.
New World hop-infused beverages include Hazy IPA, NEIPA, and Feral Biggie Juice.
And these are just the most famous of hops grown around the world. Today, their number exceeds 12 types, and this list is constantly updated with new items.
Quality Grades
In compliance with GOST R 8473-57, three product categories are established for harvested fruits, taking into account their moisture content, color, integrity, amount of resins, and impurities.
First grade
This includes light and golden-green cones with impurities of no more than 0.5% of their mass. They are characterized by a gentle clean aroma, humidity up to 13%, and at least 15% resins.
Second grade
These are whole fruits of a yellow-green hue with a strong aroma. They must contain at least 13% bitter substances.
Third grade
Cones may have small defects, differ in a rich green-yellow color and brown spots. Impurities – up to 5% of weight, moisture content – not more than 13%, and resins – up to 10%.
Storage Techniques
Most agricultural products are stored in dried form. And hops are no exception. To prepare it, various modern methods of dehydration allowing for various dryness are used:
- Cones – the easiest and most traditional form. This way, flowers retain their taste and aroma better, besides, they are easily removed from the wort due to floating to the surface. There is only one downside – the cones take up much space.
- Briquettes – in general, they are the very same cones, but more dehydrated. As a result, they are compressed into a 15-gram disc plug. This method is as good as the classical technique, but the finished product takes up less space.
- Granules. Cones are not only dried, but also crushed, powdered, and pressed into pellets. Particles stick together due to essential oils and resins, so the granules do not break up. And although they are compact when it comes to storage, the beer brewed with them is often said to go bad.
Extracting is a special technique. While the first three options used different degrees of drying, here, the technology is based on obtaining a liquid form. Cones are put in ethyl alcohol and liquid carbon dioxide, which extract oils, esters, resins, and acids. It results in obtaining a concentrate in which the content of these substances can be regulated. There are no difficulties in storage as such.
Another relatively new and still tested form is hop powder. This concentrated product reduces amount of plant waste.
The final stage of working with hops is its addition to the future beverage. This is the so-called hopping process, which can imply 4 technologies: first wort, continuous, chilled, and dry. But in most cases, manufacturers use a combination of several methods, which allows them to achieve an original, and sometimes authentic, aroma and taste. This approach is typical of private breweries, as well as when creating craft beers.
