Minimally Processed Foods : fermented Grain and Sugar
englisch: beer
Introduction
The starchy beverage beer is the most popular of the alcoholic drinks, which in turn account for the majority of the semi-luxury foods.
It is well known that German beer is subject to the German purity law and may by tradition contain only water, hops, malted barley or wheat, and yeast. With top-fermented beer, or ale, sweetener is also allowed. In contrast, imported beers may also contain other additives, or may be brewed from other raw materials. Such beers will not be discussed further on this page. Other components may also be added to mixed beer drinks, but the beer itself must still always comply with the purity law.
Although beer in Germany always consists only of the same four basic substances, there are over 6000 kinds of beer in Germany alone, with some very strong regional differences (for example, dark ale is drunk in the Rhineland, wheat beer in southern Germany). This is possible because of the great latitude that brewers have in the production process. Different yeasts, varying lengths of time for cooking and storage, differences in temperature control and numerous varieties of hops make it possible for each brewery to develop its own house recipe.
Classification according to types and varieties of beer
One way of categorizing beer is into top-fermented and bottom-fermented. This has nothing to do with how much sugar is fermented or how much yeast was required for fermentation; rather it refers to the type of yeast cultures used. Bottom-fermenting yeast strains settle on the bottom of the fermenting vat after they have done their job, while top-fermenting strains form coherent colonies that swim on the surface of the liquid following the brewing process and can be skimmed off. The best-known top-fermented beers in Germany are Altbier (dark ale), Kölsch (pale ale), and wheat beer. These were the types predominantly produced and consumed prior to industrialization. The name Altbier as used today implies that the beer has been produced in the old, traditional manner (see Production, below). The lighter varieties of lager beer that are drunk more today (aside from Weizen, Weißbier and Berliner Weiße – i.e. wheat beers) are brewed with bottom-fermenting yeasts.
Another way of classifying beers, in particular the bottom-fermented varieties, is according to their content of original wort. This refers to the extract content of the wort prior to fermentation, i.e. the amount and ratio of dissolved and soluble substances (sugars, dextrins, amino acids and other flavouring ingredients) in the brew. Based on their original wort content, beers are divided into four types: Einfachbier contains less than 7% original wort; Schankbier (draught beer) refers to varieties with 7–11% original wort; a Vollbier is one with an original wort content between 11 and 16%; and Starkbier (strong beer) has more than 16% original wort.
The following table [MS1] depicts how some varieties of beer are categorized according to their content of original wort, the amount of alcohol they contain, and how they taste.
Orange represents beers that are bottom-fermented, cream colour those that are top-fermented. Black beer used to be made with top-fermenting yeasts but today mostly bottom-fermenting yeasts are used; therefore, it is not colour-coded here.
Production
The production of top-fermented and bottom-fermented beers differs in only two ways:
(1) Top-fermenting yeasts form coherent colonies that swim on the surface of the liquid following the brewing process and can be skimmed off. Bottom-fermenting yeasts settle on the bottom of the fermenting vat after they have done their job.
(2) The optimal temperature for top-fermenting yeast is 15–20°C, i.e. room temperature, while that for bottom-fermenting yeast is 4–9°C.
Until the refrigerator was invented in 1876, bottom-fermented beer could therefore be brewed only when it was cold outside or when ice could be chopped out of lakes in the winter and kept until spring in caves or deep cellars. Beer made with top-fermenting yeasts was therefore the kind predominantly produced and consumed at that time. Only with the invention of the refrigerator, when there were, so to speak, an old and a new way of producing beer, did the name Altbier come into use for some top-fermented types.
Otherwise the production of both types of beer follows the same steps: malting, drying in a kiln, mashing, wort boiling, fermenting and storing.
In malting, water is added to the grain (barley or wheat) to make it germinate. The enzymes contained in the kernels and thus activated degrade the starch in the grain to simple sugar. This is important, because the yeasts added in the fermenting step cannot process the starch itself, but only the malt sugar. To prevent the kernels from being further degraded and spoiled by other enzymes the malt must be dried at precisely the right time. The drying process is carried out at various temperatures, depending on the desired degree of browning for the malt. The very high temperatures inactivate the enzymes. Light-coloured malt for lager beers of the Pilsner type is obtained at temperatures of about 80°C; it provides a pleasant, full-bodied flavour. If the sugar is caramelized at just above 100°C the malt becomes dark and the malt flavour is more typical and distinct. Such malt is used for Altbier, for example.
Prior to being mashed, the dried malt is crushed, or coarsely ground.
The mashing itself begins again with the addition of warm water and slow heating to 65–74°C. The slow process is intended to dissolve as many malt ingredients (e.g. sugar and proteins) as possible from the malt into the water. Starch that is still present is degraded to sugars. With regard to the speed of warming we speak of controlled mashing. The brewer can influence how much sugar (later fermentable with yeasts) and how many dextrins (not fermentable), and amino acids are formed from the malt ingredients. These contents are later decisive for the flavour and the wort (see below).
The undissolved protein and the glumes of the kernels are removed in the lauter tub, or straining kettle, and form the so-called draff, or grain residue, which is used in the animal-feed industry. Hops are added to the remaining liquid and it is cooked, so that the bitter substances of the hops go into the solution. This is called wort boiling. According to the amount of hops added, different types of beer result. The long cooking process permanently neutralizes all malt enzymes, kills germs and precipitates proteins from the solution, and these can then be filtered out together with the hops. However, this does not happen until the mixture has cooked so long and is concentrated to the degree that the desired extract content of the wort is obtained. This is known in trade language as original wort and serves as a criterion for classifying the various types of beer (see above).
Next the wort is cooled down according to the type of beer to 4–9°C (for bottom-fermented beers) or to 15–20°C (for top-fermented types) and enriched at the same time with atmospheric oxygen, which makes it easier for the yeasts to grow in the next step.
Now the brewing yeast cultures are added, which carry out the fermentation process. The wort is fermented to young beer and the sugar is converted to alcohol. With classical fermentation procedures this take 8–10 days. For secondary fermentation or maturation, the young beer is then filled into lager tanks, in which at a temperature of 0–1°C the remaining malt sugar slowly ferments to alcohol and carbon dioxide. This is known as storing. Storage lasts about 30 days, but for special types of beer it may be several months. During secondary fermentation the beer stabilizes and becomes clear. Stabilization means that turbidity and changes in colour are not so likely to occur later.
After it has been stored for a sufficiently long time, the beer is filtered, sterilized or pasteurized and filled in bottles, barrels or cans.
Shelf life and storage
The shelf life of a beer depends on the type and on how it is handled following fermentation and storage.
To be sure, bottled beers remain microbiologically stable for a longer period of time (best-before date 6–9 months), but they should not be kept longer than 90 days in the home, as light, heat and movement cause changes in flavour and colour and also reduce the quality of the head. Both bottled and draught beer should be stored, if at all, in a dark, airy place at cool temperatures of 4–8°C. This conveniently corresponds to the optimal drinking temperature.
In no case should the storage temperature fall below 0°C, because this leads to a loss of aroma. However, turbidity that appears at very low temperatures disappears again when the beer is warmed.
Mixed beverages based on beer, shandies
Mixed beer drinks can be made from all types of beer and consist of at least 50% beer plus soft drinks, fruit juices or other ingredients. Their alcohol content is usually between 2.3 and 3.2% vol. The first mixed beer drink was probably the shandy, a mixture of lemonade and beer which was invented around 1922. Further mixtures were developed with various sodas, but for the time being they remained purely restaurant drinks. Only since the change in the consumer tax law in 1992 and the Beer Tax Law in 1993 has the sale of beer drinks mixed by breweries and filled in bottles or cans been allowed.
Alcohol-free and low-alcohol beer
To produce alcohol-free or low-alcohol beer the mash is controlled so that the starch is converted primarily to oligosaccharides (complex sugars) and dextrins, which cannot be fermented by the yeasts. There are two possibilities:
(1) Normal beer is produced and the alcohol is extracted afterwards by means of several different procedures.
(2) The fermentation is stopped early by pasteurization, when relatively little alcohol has formed.
An alcohol content of 0.5% vol. is approved for beers termed ‘alcohol-free’.
Health aspects
As with all alcoholic drinks, the principle is that consumption in moderation is not harmful, while excess consumption can be dangerous.
From a nutritional point of view, alcohol is a poison. It leads to a one-sided and excessive intake of energy and can, if large amounts are consumed regularly, cause liver damage, inflammation of the stomach lining, nerve damage and mental problems. There is a danger of addiction.
Alcohol can be degraded by the human body, but only in certain amounts. From a medical point of view, 50–80 ml of pure alcohol daily, or 25–50 ml for women, is not a problem. Someone who consumes more than this regularly is considered to be addicted to alcohol.
In principle, the period of time in which consumption of alcohol takes place is important: While a lot of alcohol over a short time period leads to a major burden on the liver and possibly also damages it, the same amount spread over an entire day is less harmful because the alcohol is slowly but permanently degraded.
The high energy value of alcohol should also not be underestimated. One glass of beer contains 69–165 kcal (depending on type and alcohol content). In addition, it stimulates the appetite and the digestion, so that one may also grow fat from beer. Drunk in moderation, alcohol has a relaxing effect, relieves stress and promotes sleep.
Beer has further positive effects:
It contains quite a lot of vitamins from the B group that stem from the yeast. They have many different effects on the body; they are good for nerve activity, they play a role in metabolism, and they are involved in the formation of red blood cells. Ingredients stemming from the hops are relaxing, stress-relieving and sleep-promoting.
In addition, beer contains almost all amino acids that are found in our body and that it constantly needs.
Furthermore, beer acts as a diuretic, promotes the blood circulation in the kidneys, and reduces the risk of cardiovascular diseases, as long as it is drunk in moderation (no more than one to two glasses daily).
Ingredients
The caloric value depends on the content of carbohydrates and alcohol. Beer contains no fat. Some types of beer have a higher alcohol content; 1 g of alcohol adds 7 kcal, so that the amount of energy increases with an increasing alcohol content. Alcohol-free beer has a correspondingly lower amount of energy. Although alcohol-free beer has more carbohydrates (because the sugar is not completely fermented), these supply only 4 kcal per gram and do not increase the energy content as much as alcohol does.
Overall, the vitamin content of beer is very low. The B vitamins and niacin are the exception. Beer contains somewhat more niacin than most kinds of fruit and vegetables (except for legumes / pulses).
100 g contain:
Tips
* Use clean glasses that preferably have been rinsed with clear cold water and not dried. The water should have run off. Residues of dish detergent are detrimental to the stability of the head.
* Use glasses that are free of grease. Even small amounts of grease cause the head to collapse.
* A good beer does not require several minutes to be drawn or poured. Pour it quickly so that the carbon dioxide does not escape before it is drunk. Strongly foaming beers should be put down several times.
* When drawing beer, let it flow into a glass held at a slant; otherwise too much carbon dioxide will escape. If you pour the beer from a bottle, hold the glass straight up and the bottle a few centimetres above the edge; then pour quickly to obtain an optimal head.
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This article was written by
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