Is it possible to freeze and dry compressed baker's yeast?

QWhat should you do if you haven’t used up all the yeast during the cooking process? After all, it is known that at room temperature after opening the package they are stored for no longer than a day. Can the product be frozen?

At subzero temperatures, baking fungi enter a state of suspended animation, that is, sleep, during which metabolism slows down. After thawing, they completely retain their properties, so yeast can be frozen. But this process has its own subtleties.

Physical properties of yeast

Yeasts are the simplest single-celled fungi. There are more than 1,500 species of them in the world. Some (pressed bakery, beer) benefit humans, others (candida genus) are opportunistic and can cause disease.

As far back as ancient Egypt, people used live yeast to ferment foods, bake and brew beer. But only in the 19th century did scientists realize that these were not just chemical compounds, but microorganisms capable of growth and reproduction.

Nowadays, compressed baker's yeast is most often used in households. For normal life they require the following conditions:

• Availability of oxygen. You should only store the product in packaging that "breathes". For example, in paper.
• Slightly acidic environment. The normal pH value is 4.5–5. During long-term storage in an alkaline environment (for example, in salt), yeast cells are inhibited.
• Optimal temperature. Most types of yeast, including baking yeast, cannot withstand 45–50 degrees. Therefore, there are no living microorganisms in finished baked goods, as authors in some media like to scare. But low temperatures are not a problem for yeast. The ideal option for fresh pressed ones is storage in the refrigerator.

So is it possible to freeze a “live” product? Yes. But only in compliance with the rules described below.

How to freeze yeast?

Fresh baker's compressed yeast is stored the least. In the refrigerator - no longer than 2 weeks. However, such a product has a number of advantages. Compared to dry and granulated mushrooms, it makes the finished baked goods more fluffy. In addition, it contains a maximum of vitamins.

How to properly freeze compressed baker's yeast?

1. Check the freshness of the product. There is no point in freezing spoiled mushrooms. A truly “living” product has a delicate creamy color and a slightly sour smell. When pressed, the block easily crumbles.
2. Prepare portions. You should not put a large bar in the freezer, because most likely you will not be able to use it at one time. But microorganisms cannot be re-frozen: this will cause them to lose their properties. It is better to cut the block into pieces of 50–100 g.
3. Start packaging. Yeast can be packed in parchment or plastic bags. Plain paper will not work because it will get wet when defrosting. Write the date of freezing on the packages with a marker.

The product can be stored in the freezer for no more than 1 year.

How to defrost yeast correctly?

Yeast does not tolerate temperature changes well. So you can’t just take a block out of the freezer and leave it on the kitchen counter.

To begin with, the temperature should be increased to 6–8 degrees. Transfer the frozen pieces to a plate and refrigerate for 8 hours. Drain the resulting water and use the product for cooking.

To be on the safe side, we recommend checking the viability of the fungi immediately before cooking. Dissolve 1 teaspoon of sugar in a glass of water at room temperature. Put a piece of yeast there. If foam appears in the glass within a few minutes, it means that the fungi have not died.

How to dry yeast?

In addition to freezing, you can dry fresh compressed mushrooms to extend shelf life:

1. Crumble the block.
2. Add a small amount of flour to the mixture and mix.
3. Line a baking sheet with parchment paper and sprinkle the yeast on it.
4. Leave the crumbs to dry in a well-ventilated area at room temperature.
5. When the mushrooms are well dry, pour them into a glass jar. Cover the neck with paper or cotton cloth and tie it with a string.

The product can be stored for up to 6 months in a dark, dry place. In the refrigerator - about a year.

How long does dry yeast from the store last?

The lower the moisture content of a store-bought product, the longer it will last in a sealed package. Thus, instant yeast (40%) can be kept in a dry, dark place for up to 6 weeks. Active (9%) remain viable at room temperature for 6 months, and instant (3–4%) - 2 years.

What if the package was opened? Then you have two options for storing dry yeast, regardless of its type:

• in the refrigerator – up to 1 month;
• in the freezer – up to 1 year.

In the second case, it is recommended to package the product in fabric bags or plastic bags.The rules for defrosting are the same as in the case of pressed mushrooms.

So, yeast likes low temperatures more than high ones. Therefore, you can safely store them in the refrigerator or freeze them. It is better to prepare the dried product yourself from fresh bars, since in the store you risk buying dead fungi in the form of powder or granules. Before adding yeast to the dough, be sure to check its viability.