What you need to know about yeast
The quality of yeast depends on the speed of recoverytest and the splendor of future baking. Some landladies trust only raw yeast, considering dry fast-acting undesirable chemistry. It is unlikely that any mistress, "conjuring" in her kitchen, thinks about the fact that yeasts are unicellular microorganisms and a pressed pack of yeast is nothing more than the maximum accumulation of yeast cells. Naturally, they have a strong reaction due to their concentration. In the production of such yeasts, molasses (waste from beet production) are used as the main food for them. Only molasses is not enough, and at the yeast plant, nitrogen and phosphorus are added to it, acidified prematurely. The quality of these yeasts is determined by the characteristic cream-yellowish tinge and firm consistency, they must crumble under pressure, but not be smeared, what happens when the yeast from the cold is sharply moved to heat. If the yeast was purchased ahead of time and stored in the freezer, this will not affect their properties in any way. Low temperature is not terrible, it simply hinders the process of vital activity, and the yeast seems to fall into anabiosis. Therefore, if the raw packet of yeast has been frozen, then it should be subjected to slow thawing at a temperature of no higher than 8 degrees. Otherwise yeast will turn into a formless mass and spread out. The disadvantage of such yeasts is that the shelf life is limited to only days. In a refrigerator without freezing, they can stand for two weeks, and in the freezer - up to 3 months. Therefore, it must be taken into account that even during freezing their term is limited. Dry yeast began to be used in home cooking only from the end of the XIX century. Many recipes today indicate the amount of raw or dry ingredient a housewife chooses. Dry can quite replace pressed, as they represent the same, only in the dried up kind. However, such yeasts are subdivided into dry active and dry fast-acting ones. Sometimes these concepts are confused and put the active granules directly into the flour, which is fundamentally wrong. The first representatives need a preliminary soaking in warm water no higher than 37-38 degrees. They should be held in a liquid for 15 minutes so that they "bloom". Fast-track such training is not needed. It is important to observe the proportion of yeast relative to the amount of flour. Typically, take 50 g of yeast per 1 kg of flour, but if the baking is sweet and rich, the amount of yeast increases by about 2 times. For the bread dough, on the contrary, it decreases. As for dry yeast, they should be taken 3 times less than raw yeast. Currently, in some supermarkets you can find not only dry yeast imported, but also raw. When using them, you need to consider that they are behaving much more actively. This means that it will take at least 2 times less raw materials and 4-5 times more dry ones. Overdosing of yeast is highly undesirable, since the dough will only get worse from this, and baking will be unpleasantly given by a sour smell. 
The role of yogurt in kneading the dough
To activate the activity of any yeast,they need to create favorable conditions: a liquid medium, the necessary nutrients (sugar, nitrogenous and mineral compounds) and the temperature necessary for fermentation. The presence of sugar and a weakly acidic medium is necessary (alkali is harmful to them), because yeast "feed" on glucose, sucrose, maltose, and from nitrogenous prefer protein hydrolysis products. Therefore, it is known that one of the ingredients of the test is milk or sour-milk products. Some housewives start on milk or kefir with just dough for buns or other sweet pastries, and for pies prefer recipes on a water basis. However, the yeast dough on kefir is such a universal "thing" that once you try one of these recipes, you want to bake everything out of it, just enough for your imagination. Silky consistency is felt even when kneaded, but it's not even easy in its suppleness and elasticity in work. The main thing is that baking from kefir dough does not last long, which can not be said about the test on milk. And as for its delicious taste, you can add ode! It is not necessary to have one kefir out of the liquid. After all, if the dough is started with the participation of dry active yeast, then, according to the technology, they need to be dissolved. Do this should not be in kefir, but in a small volume of warm water or milk with the addition of a pinch of sugar to activate the process. This is the preparatory stage. If yeast is used for preparing the dough, then only kefir is taken, which can replace the entire liquid component of the dough. I must say that any sour-milk products give a splendor to the dough and it fits more quickly than on water or milk. When the positive experience of observing the ratio of flour and other ingredients is reached, you can experiment and add to the recipes not only kefir, but also whey or cottage cheese.
The most popular recipes for kefir
One of the most common "grandmother's" recipescontains the following ingredients: flour (2.5 cups), kefir (1 cup), vegetable oil (½ cup), sugar (1 tbsp), salt (1 tsp), yeast raw (50 g). Naturally, the yeast first dissolves in kefir at room temperature, and then mixed with other constituents. The uniqueness of the test in the speed of recovery, this is enough for 1.5 hours. It is suitable for both sweet baking, and for khachapuri or garlic rolls. Also, without opaque, you can make baked pastry using another recipe: kefir or whey (300 ml), yeast (50 g), margarine (250 g), salt (1/2 tsp), sugar (1 / 2 cups), eggs (3 pieces). Such dough immediately after kneading is placed in the refrigerator, where pre-melted margarine will slightly harden. Experienced cooks recommend doing this at night, and baking in the morning. Even if the plans changed in the morning, it's not terrible: the longer yeast dough on kefir is in the refrigerator, the better. For those who are just starting to master the baking art, this recipe is advised to be used at first, because it is rather unpretentious in the work. The above recipe somewhat violates the tradition of ordinary concoction, because as everyone knows, fermentation is activated at a temperature of 25-35 degrees. All the housewives are anxious to put their wax in a warm place. And this is true, but not for all methods of preparing the test. 
Traditional test recipe
The following recipe requires warmth, but not necessarythink that the warmer, the better for the speed of the process and the quality of the test. On the contrary, if the temperature of the surrounding air exceeds 45 degrees, yeast will also die. So, you need 600 g of flour (and if kefir is very liquid, then more), a glass of kefir, 50 ml of milk, 25 g of raw yeast, 1 tsp. salt, 75 grams of margarine or butter and 2 eggs. The amount of sugar depends on what kind of baking is supposed, sweet or not. In the unsweet enough, a tablespoon, and a sweet three times more. Do not be zealous with sugar, since its overabundance will only "slow down" the fermentation. This dough is called heavy. It is better to add sweets later, at the expense of sweet stuffing. For pies, you can use a recipe without eggs or with the addition of 1 egg. Who loves a more stringy dough, should reduce the amount of margarine. Though on yogurt it in any case will not be so stringy, as on water. The dough will rise for 1.5 to 2 hours, but it should be crushed with a wet hand and allowed to rise a couple of times. It is important to feel the consistency consistency, despite the fact that all proportions are observed. After all, it's impossible to measure everything down to a milligram. Sometimes it matters not only the density of yogurt, but also the size of the egg. Large 2, and small ones will be required already 3. In order not to be mistaken with the density of the dough, it should be scooped up with a palm and tried to shake off the hand. A good dough will not stay on your hand and do not drain, but slowly fall off. From the third test, you can sculpt any pretzels you like. Having placed them on a greased baking sheet, you should give the future pies or rolls a minute or 40 minutes, or even more. But baking baking quickly: 15 - 20 minutes at a temperature of 180-200 degrees.
Culinary tricks
Kefir for dough can be used absolutelyany, but often the housewives send a not very fresh product into the baking. Of course, do not throw away the good! But you need to take into account in this case that the peroxide will affect the acid and baking. Therefore, it is better not to use this kefir in isolation, but dilute it with water or milk. The dough will turn out lush, porous, but moderately acidic. A large amount of "out of trust" kefir is more correctly used for another type of test, without yeast, but with soda. Wishing to benefit the body by sending a dairy product with bifidobacteria to the dough, it must be understood that in baking all these properties will not matter, they will simply be lost. It is better to drink such kefir in a fresh form. When preparing a test, there is sometimes a controversial question whether it is necessary to cover tightly the container, where it fits, or should be given a test to "breathe". According to the master of his craft, it does not matter. The activity of yeast is the same as in the aerobic and anaerobic state. When the test is not enough, it can be placed in a cellophane bag, leaving room for lifting. If time "suffers", then the package is placed in the refrigerator for a slow rise. Just before cutting, the dough should be taken out and allowed to warm up a little. Dry fast-acting yeast is an aid to busy business ladies who prefer recipes for quick baking. However, this type of yeast is also successfully used for the preparation of yeast pancakes on kefir. For this purpose it is enough to mix flour with salt, sugar and yeast and pour warm yogurt. After 30 minutes the dough will already rise and there it is necessary to send 1-2 eggs and warm water. It is possible and hot - it will be custard, delicate pancakes, but thick and with a piquant sourness. Kefir pancakes are also not forbidden to be yeast.
