Yeast is a living organism that has long been cultivated by humans and used to make food and drink. If you ask what yeast is made of, it will be impossible to answer in one word. The fact is that they existed on earth even before the birth of human civilization.
Unique microorganisms
Yeast is a living microorganism that can feed and reproduce. They are very sensitive to temperature extremes and food composition.
Yeast mushrooms exist everywhere in nature. They feed on biological raw materials, and in the process of metabolism, that is, fermentation, produce new chemical compounds. The number of these microorganisms in nature is so great that if we compare it with the number of grains of sand in the seas and on land, the yeast spores will be many times more. Needless to say, there are also a great many varieties of yeast fungi. Some are good for our health, while others are bad. All living yeast intensively emit carbon dioxide and alcohol fractions.
Types of mycetes used in the production of bread dough
In the food industry, and in our case in the baking industry, only some types are used, namely those that, when they eat a nutrient substrate, emit a large amount of carbon dioxide. It is thanks to the bubbles of this gas that the bread is porous. Its quality is even determined by the way the loaf behaves, if you squeeze it to connect the opposite sides and let it go. If it recovers to its original state, this means that the bread is of high quality.
There is also a lot of yeast in this class. In the modern baking industry, for the manufacture of soft bread, mushrooms from the saccharomycete family are most often used.
Bakery Yeast and Sourdough
Every bread maker knows what baker’s yeast is made of. The conversation about bread yeast is best started with a story about leaven. It is mentioned in ancient books dating back several millennia. Sourdough and baker's yeast are one and the same. Sourdough is a product, the attitude to which has always been especially careful. All actions with her were surrounded by many signs and rituals. The products from which the initial sourdough was made were carefully chosen. The most successful were stored and cultivated, passing from generation to generation.
Quality bread is a guarantee of good health
The fact is that different types of mushrooms exist under different conditions. And even if the dough from yeast bred on the same raw material turns out to be very tasty, this does not mean that this leaven will prove similar in the next use. There is always the possibility that the original mushroom culture was replaced by a new one. This is not visible to the naked eye, but the next batch of bread may be tasteless and even harmful to health. It is no accident that in ancient times one of the ways to destroy an enemy tribe or other community was this. The scout penetrated the enemy camp and spoiled the leaven, since it was believed that bread and water were the most important food for humans. Health and life depend on the quality of these two products. What do yeast mushrooms do with a product? They change its appearance, texture, composition and properties. To understand the mechanism of their work, you need to figure out how and what baking yeast is made of.
Hop sourdough
Take one glass of hop cones, fill with two glasses of water and put on fire. Cook until the volume of liquid is reduced by half. Cool to 37-40 degrees and strain. In a hop broth, put one or two tablespoons of sugar and half a glass of flour. Cover with gauze. This is necessary so that the yeast receives oxygen, otherwise they will die. Place the container in a dry, warm place away from direct sunlight and drafts. In two days, you will grow a culture of baker's yeast, the same yeast, which, taking a little, can be used repeatedly in baking. Typically, 1 kg of flour requires from 50 to 100 g of sourdough.
Unbelievably tasty is obtained sourdough bread from barley malt with honey and hops. Malt is flour milled from sprouted and dried grains. Its microbiological composition is fundamentally different from the composition of flour from polished grain.
The secret to delicious beer is malt, hops and yeast.
Hops and barley malt are what brewer's yeast is made of. The brewing process is extremely simple. Whole barley grains are soaked for germination. Rye grain is also what beer yeast is made of. However, due to the specific taste, barley is often used. It is necessary to germinate. Yeast does not like sprouted grain - it contains a lot of starch and a little sugar. When the embryo is activated, that is, germination, the amino acid present in it, amylase, is activated in the grain. Amylase and hydrolyzes starch into sugar digestible for mushrooms. Sprouted grain, called malt, is kept at rest for some time to ensure the most complete fermentation, then it is ground, mixed with water and boiled with the addition of hop cones. It turns out wort - an excellent feed for brewer's yeast.
Two types of yeast are used for beer. Some ferment the drink on the surface and live at a temperature of + 14-25 degrees Celsius. These so-called high-level yeasts form a froth on the surface of the wort. At the end of the process, the fermented yeast mass sinks to the bottom. There another colony begins work - grassroots yeast. They work in colder conditions - at temperatures from +6 to +10 degrees.
The difficult art of a baker
In the old days, before the advent of electric ovens and refrigerators, the process of making bread and preserving the yeast was almost a mystery. They did not give leaven on loan, and when they made bread (this process took at least two days), they tried not to make noise, not to slam the doors and shutters. We monitored the dough in order to have time to timely hug it and prevent it from souring. Failure to comply with the conditions is fraught with the development of another yeast culture, since different yeasts need different temperatures, densities and composition of the nutrient substrate. Useful yeast can turn into harmful yeast. It was believed that in a bad person bread is always tasteless. They tried to buy bread only from a certain master.
Yeast - a source of healthy vitamins
In this way, yeast ferments the bread base, which also changes in chemical composition. Good bread consists only of flour, water and sourdough, in which there is a small amount of sugar to feed the yeast. The pleasant taste of bread is a consequence of the fermentation of flour with yeast. Yeast enriches bread with B vitamins and vitamin D. When baked in a Russian oven, most of the nutrients were preserved. It is unclear whether this was known in the old days, but the temperature of the oven had three characteristics - before, after and during baking. Soft uniform heat during the preparation of bread was below the boiling point of water. With very high heat, the product burns out on the outside and does not bake on the inside.
Modern dry yeast, unlike sourdough, is very convenient, as it is less capricious and more stable. Even inexperienced housewife can bake excellent bread from them. In this regard, a logical question arises: "And what is dry yeast made of?"
Sugar, water, air and a temperature of 30-50 degrees - the optimal environment for saccharomycetes
Since yeast is a living organism, they, by and large, are not made, but are grown from ordinary yeast mushrooms used in making bread - saccharomycetes, that is, bacteria that eat sweets - sugar, sucrose, fructose, etc. In factories for feed baker's yeast use waste beet mass - molasses. Sugar beets - this is what raw yeast is made from in domestic enterprises.
Molasses
Yeast mushrooms grow very quickly on this product. Molasses, also called black molasses, is a thick viscous liquid of a very dark color. One ton of substrate grows up to 750 kg of yeast. Molasses from beets or sugarcane - this is what baked yeast, as well as instant yeast, is made of. Currently, with large volumes of production and high demand for prepared yeast, these are the most common foundations for growing sugar mycetes. However, these mushrooms can grow well on other plant materials rich in natural sugars. If you use a starchy substrate - potatoes or grains, then it should be subjected to fermentation.
Safety of a modern product for raising the test
Thus, it is obvious: what baker's yeast is made of in modern factories does not pose any harm to health. With the proper storage and use of modern dry fast-acting yeast, you can not be afraid that they will develop new cultures that are harmful to health, because in food production only those yeasts that are well studied for resistance to various transformations are used. Moreover, they are much safer than “wet” sourdough prepared at home. In dry yeast, metabolic processes are in a static state. Metabolism begins only with the addition of sugar and liquid - water or milk.
Having figured out what yeast is made for baking bread, it remains to be decided whether to give preference to raw pressed or dry instant (instant).
Pressed
The yeast mass grown on molasses is separated, that is, filtered. Water is added to the yeast and separated again. As a result of several procedures, the yeast mass acquires a grayish color and a viscous consistency. The vacuum apparatus removes excess moisture. This process is called sublimation. The resulting gray, plastic, clay-like substance is cooled, divided into portions, formed into briquettes, wrapped in wax paper and sold. Such a product should be stored in a refrigerator at a temperature of minus 2 degrees Celsius and ambient humidity of about 72-75%. Shelf life is 12 days. In retail, such yeast is nowadays not always found. In this case, I would like to know what compressed yeast is made of if they are such a rare product. After all, we very often tend to think that the products that decorated store shelves 20 years ago were much better than current ones. This may be true, but not with respect to yeast.
It turns out that the point is not what pressed baked yeast is made of, but that they are extremely inconvenient to use. It is extremely difficult to withstand the necessary humidity and temperature in the dry cold of a modern household refrigerator. A period of 12 days also limits the housewife. Usually, baking from yeast dough is done on weekends. There is too much pack of pressed yeast for one time. For a family of 4 people, even with invited guests, half a pack is more than enough, and until the next weekend such yeast cannot be kept active.
Dry
Dry yeast has long and firmly taken its place in our kitchens. I must say that, despite the modern electronic technologies that are used by the manufacturers of this product, dry yeast was known even in pre-Christian times, when the sourdough was dried in order to preserve it during transportation over a long distance. What dry yeast is made of is no different from what pressed yeast is made of. This is the same sweet molasses and, in fact, the saccharomyces themselves.
The process of their manufacture is longer, because the grown and partially dehydrated yeast mass should be dried and turned into granules. There are three types of dry yeast. These are dry active yeast, dry active instant and dry active instant instant. Sugar syrup and saccharomycetes are what fast yeast is made of. Only dehydration technology is different. If low-temperature drying using the technology of the Russian oven is used for ordinary dry yeast, then instant ones are dried in a vacuum by sublimation. In the first method of drying, a product with a rather weak vital activity is obtained. Despite the fact that the lifespan of such yeast is 12 months, they barely reach its end, so significantly losing the ability to ferment muffins, that they can be advised to buy only at the beginning of the expiration date stated on the package. Therefore, reading the accompanying inscription on the package, carefully study not only the information on what baker’s yeast is made of, the composition of the product, its calorie content, the name of the manufacturer, but also the date of manufacture of the yeast and its validity.
Emulsifiers and Antioxidants
If you are against adding emulsifiers and antioxidants to the product, use compressed yeast or yeast. However, do not forget that in them the presence of unhealthy microflora and chemical elements is possible. Emulsifiers are added to the raw yeast mass before drying. All dense mass is poured on a pallet in a vacuum chamber. A vibration is created there, it divides the dried substrate into small fractions, which are then packaged in sealed bags. An emulsifier and antioxidant are added to the yeast to prevent undesirable growth of the fungi and against their adhesion before they are used in the dough. It is not necessary to think that these additives are included in the composition in order to harm our health. This opinion is deeply erroneous and very strongly gives away amateurism and "yard competence" in matters of molecular chemistry. Sometimes you can even hear this: “Everyone knows perfectly what yeast is made of. The composition of good yeast is just sugar mycetes and nothing else! ” However, even in pressed yeast, vegetable oil is poured so that they do not begin to multiply actively before they get into the sweet solution. Inquiring what dry yeast is made of (the composition is described on the package), you can see that the product contains natural yeast, emulsifier E 491, antioxidant E 320, starch or rehydrate. Those cases where only yeast is included in the composition of dry yeast and nothing more, they only say that the manufacturer did not provide complete information about the composition of his product, and not at all about the absence of stabilizing and disinfecting impurities. People with a sense of humor say that fear of food can kill much faster than food itself. This also applies to nutritional supplements.
It’s a pleasure to make bread from dough mixed with instant instant yeast. Instant Instant Saf Yeast has proven itself very well. Knowing what Saf-Moment yeast is made of, and this is indicated on the label, you feel much more confidence in the manufacturer than if he did not write that rehydrate was introduced into the yeast mass to control the moisture level. This yeast can not be bred in sweet milk or sugar syrup. They will perfectly raise the dough if you pour them directly into flour or knead in the finished dough.
Ode to sugar mycetes and vacuum
What to prefer - yeast or sourdough, everyone decides for himself. However, what yeast is made of, we figured out. On sugar molasses, it is very difficult, or rather impossible to grow, not sugar mycetes, but any mushrooms dangerous to health. Alcohol and carbon dioxide emitted by these small workers destroy the pathogenic microflora, and vacuum sublimation and hermetic packaging guarantee the absence of unsanitary impurities. Ferment is a good thing, but is it possible to cook it as sterile as it is?