About yeast. For
Vlada and
Natalie
1.Natashik, there is no a priori yeast that calmly survives direct contact with air, if only because they begin to revive in the air, oxygen will not allow them to stay in an inhibited state.
Therefore, they are strictly isolated from the air. This is done in two ways:
- vacuum (cafe-instant)
-protective sheath (cafe-levure). These, which with a protective shell withstand some time in the air due to the shell.
but the whole problem is that those that can withstand exposure to air require mandatory activation in hot water (like cafe-levure). And those that cannot withstand the stay, those can simply be thrown into flour.
Perhaps there are some that are kept in the air, and in flour it is possible, but I have not seen them anywhere. Including Luda. Therefore, I can not find which ones are suitable for the dispenser. Most interesting.
And about keeping it in the air, you meant "tempering the yeast", then look below about it in Luda's article.
2. Yeast strife with yeast. Different strains, different properties. Natashik, you quoted on the forum of technologists
recommendation for Kaf-levure, and its field of application is very different from Kaf-instant.
You can't give active links here, so I'll just copy too. Anyone interested can easily find all this on the site himself.
Kaf-levure is very different in composition from Kaf-instant. I will not list the differences, the most important thing is that only cafe-instant can be used for frozen semi-finished products without losing their properties
and they have shape conservation is fundamentally different. Pay attention
Scope information from the manufacturer's website
Dry instant yeast "Saf-Instant" with a red label is recommended for the manufacture of bakery products with a sugar content of up to 10% by weight of flour. This type of yeast can be used for cooking frozen semi-finished products with short shelf life. In this case, it is recommended to add yeast 5-8 minutes before the end of the batch.
Therefore, either you need to ask the technologist exclusively about this brand of yeast, or take on faith my opinion that it is the instant that will withstand freezing.
They can withstand freezing even after being activated in the dough.
I also quote Lyuda (just about the residual yeast activity.)
mariana_aga
Jan. 21st, 2014 03:35 pm (UTC)
Frozen yeast should be aware that compressed yeast is normally stored in the freezer, up to a year at -20C without problems. But they DO NOT BREED well in the dough after defrosting. That is, it is better to put them on a bezoparny dough. Or mix yeast and dough and dough.
And instant ones - you can let them out of the freezer into the dough, as far as I understand. They have trehalose (intracellular sugar in yeast) dofig and trehalase enzyme. This protects the cell from stress.
And here is Lyudochka's extensive scientific article on yeast. Read with comments and there will be no questions left, how to preserve instant yeast without losing its properties and how to temper the yeast
cloud.
I will finish the result of the long post above with a quote from Lyuda
For home use, this means filling the yeast from a large pack into small bags or jars, sealing it tightly (you can vacuum it) and taking out small portions as needed, opening and quickly closing the jar, immediately putting the yeast back into the freezer.The particles there are so small that they instantly heat up to room temperature if left open on the table. The whole trick is that if dry yeast is packed in small jars for freezing, then the total time of opening the jar during the consumption of yeast in it will be less than 48 hours - a safe exposure to moisture and oxygen from the air, as indicated on the unopened instant pack.
Added Sunday Mar 12, 2017 01:47 AM
The only thing, before freezing, Luda kept them only in the refrigerator. I will quote her very first experience to complete the picture of storage just in the refrigerator.
mariana_aga
Dec. 14th, 2012 at 2:41 PM
Instant yeast in the package loses about 10% of its strength per year of storage at 20C and 25% - for a year of storage at 35C. So store even unopened packets and sachets in a cool, cold place or even in the freezer at -20C if you buy a lot and for a long time.
At home, I personally do not notice a difference in the behavior of yeast until a month after opening the package (I store it at 4C after opening in a jar with a screw cap), because they are stored for 4 months at 3C, opening the jar 3 times a week to select yeast for baking, lose only 8% in lift (link). But yeast experts still recommend to bakers no more than a week of storing instant in the cool after opening the pack, because increasing the dose of yeast by 8% in order to compensate for the loss of lifting force in "old yeast" will have a significant effect on both the cost of bread and quality of the dough (more dead yeast - more glutathione, more oxidizing agents in the dough - the higher the cost of the dough).
Oddly enough, instant yeast dies in smaller quantities when in contact with room temperature water, compared to dry active yeast. Instants also do not like the cold and must be mixed with flour and then warm or hot water. But upon contact with water at 20C, they lose about 20% of their power, compared to 40% losses in dry active in water with T 20C.
Instant replaces pressed (of the same strain) in a ratio of 1: 3. For example, instead of 10g instant take 30g pressed. When freezing the dough with instant yeast, it will withstand about 2 weeks of freezing (while the dough with pressed yeast can be frozen for long periods)
mariana_aga
Dec. 16th, 2012 03:55 am (UTC)
It takes me half a kilogram of SAF-gold in about six months, that is, if almost all the bread and baked goods in a family for 2-3 people are baked at home (we eat bread daily from 0.5-0.7 kg of flour, 100 kg of flour for six months, 5 g of yeast for kg of flour - 500 g of yeast for six months). So for the first time, I just poured from a large pack of yeast into a jar, the rest in a large pack I twisted tightly with an elastic band and hermetically packed in a plastic bag with a zipper and kept both in the refrigerator at 4C. A small jar was often opened within a month, and a large bag only 6 times in six months, in order to pour 50-80 g of yeast into a small jar for every day.
Thus, it was possible to keep the lifting force of the SAF-gold unchanged, i.e. to avoid frequent contact of yeast in a large pack with warm humid air.
Now I have switched to storage in deep freeze, because in addition to SAF-gold I simultaneously use a variety of yeast of other strains and in the freeze they also lie like this - one small jar that gets out and opens from time to time, and another large amount - in a hermetically sealed in a bag, a large pack that opens every few months to fill a small jar. So a pack of SAF-gold will be enough for me for several years.
when using SAF-gold from the freezer, I give them time to first adapt to room T for a few minutes and only then to 40C. That is, not a temperature shock from -20C directly into a liquid with + 40C, but first I measure it out and in a bowl they warm up for several minutes, sometimes mixed with flour, in order to adapt to T 20-25C and humidity at 15% (flour moisture ), instead of 4% (moisture content of dry yeast in the freezer), and only then I mix them with hot water or hot flour mash when kneading dough or dough.
Feb. 25th, 2013 02:17 pm (UTC)
Now I store all yeast in the freezer at -20C. ALL. All types and brands.
If the package is already open, I fill the yeast in small jars from the yogurt maker, filled with yeast to the eyeballs, and screw the lids. One jar is in the refrigerator - the one I'm using now, and the rest are in the freezer. I take out one at a time and put it in the refrigerator, as it is used.
Instant can be restored as dry active or not (i.e., with soaking and / or with activation in sweet water or flour mash), it depends on the recipe.
The minimum they need to be given is at least a few minutes at room T, just in a bowl or mixed with flour (optimally half an hour mixed with flour), while you measure out other ingredients so that their temperature and humidity equalize to room temperature and to humidity air in the room or to the moisture content of flour (i.e., from 4% to about 14%), this significantly improves their activity and the ability to recover from a dry state to an active, vigorous and healthy state.
Added Sunday 12 March 2017 02:03
Sveta and Rita
girls, well, dance from the chemical-physical composition of flour. If someone advised you to store eggs in the freezer, or virgin sunflower oil, then you would immediately estimate the result, but here the same thing.
Flour CZ is proteins and vegetable fat, only in small droplets in a starch shell. A complete analogy.
Will the freezer keep food? Yes of course. If it's not tainted yet. Will the taste suffer? well, like eggs after the freezer. Baking without problems, raw is not the same
At the same time, rye CZ is even more tender. It contains more protein.
And - the most important answer to this question is already on packaging flour.
Manufacturer recommends storing between 0 and 25 degrees.
This means that all the taste will be preserved.
That is, after the freezer, a slight change should be expected.
Well, as on the packaging of eggs, no one will write that they can be put in the freezer. Because the direct properties will change.
From here ... make your own conclusions. In order to have the identity of the product, it is not recommended to put it in the freezer, that is, it is possible only if there is no other way out. Like eggs, but without shells.
It is best to store at the lowest degree on the package in the refrigerator. Because the higher the degrees, the more the bugs like flour and the more carefully the humidity requirement must be observed. The manufacturer writes about 6 months, but does not specify that this is at 24 degrees of heat
Why? Yes, because in fact you are raw eggs without shells and store fresh natural oil in starch. Will you leave them in the heat?
Added Sunday Mar 12, 2017 04:19 AM
freezing compressed yeast
Natashik... You write
but in practice, as we can see, it happens in different ways. People freeze compressed yeast and use it for months, and in my freezer a week later the yeast becomes very bad.
theoretically, freezing and thawing of pressed yeast is more demanding operations than dry yeast. There is practically no moisture in dry yeast, which expands when freezing and destroys living yeast cells. If, in a simple way, he strives to break their cells. And if you defrost it quickly, then the poor cells lose it too quickly and additional death occurs.
gatta
Dec 15, 2012 19:36 (UTC)
Luda,
I once tried to freeze the pressed yeast, but for some reason it died after thawing. Since then, I have decided that they cannot be frozen. It turns out that I was wrong, I must try again.
mariana_aga
Dec 15, 2012 20:27 (UTC)
....... I will try to freeze and pressed. There the secret is that there should be a slow freezing, a decrease in T by 1 degree per minute (not flash freezing), store in deep freeze (below -18, -20C, i.e. lower than in a conventional self-cleaning freezer without frost and fluctuations in T, and slow defrosting overnight in the refrigerator only the portion that is needed for baking.
So now we are savvy and we can freeze on science.
Pressed yeast can be frozen at -18C for up to a year, if then slowly thawed in the refrigerator and used within 24 hours after thawing.Thawed yeast will be slightly more crumbly compared to yeast before freezing,
.. because they dry out a little in the freezer. But they will ferment normally, the difference in gas production between fresh pressed and defrosted at 4C frozen, stored for a year at -18C, is only 3%.
everyone has different refrigerators. Perhaps someone automatically gets the desired result and naively believes that this is the case everywhere and always. Then it is possible that there is insufficient residual yeast activity and would not work in the dough, but no one checks
