The yeast is not "made": it is cultivated. It is not the product of an industrial process that can intensify with increasing demand. Here's how it was born
In time of lockdown, the Italians have rediscovered the pleasure of kneading and baking. So that purchases of flour and yeast have rocketedin recent weeks, by + 205% and + 203%, as noted by the Coop Research Office. So it can happen that on the shelves of the supermarket it can really become a business to find these ingredients.
In particular, fresh yeast is almost untraceable, despite the fact that the companies that produce it are at work non-stop, as confirmed by Piero Pasturenzi, president of the Assitol Sugar Yeast Group, the Italian Association of the oil industry representing the sector. "Our goal is to respond to consumer demand, ensuring the high quality of our products and, at the same time, the health of our workers." But the yeast does not does: Yes cultivates. It is not the product of an industrial process which can intensify as demand increases, but a microorganism that comes to life from a by-product of agricultural origin. «Companies create the most favorable conditions for them to reproduce in the presence of oxygen; basically everything is based on the fermentation of sugar, a process that has nothing artificial and which obviously has its time. " That cannot be contracted.
How yeast is grown
Welovelievito.it, the Assitol website created to dispel false myths and promote correct information on yeast, explains it well. Brewer's yeast is a living organism, belonging to the mushroom kingdom, fed and reproduced in a completely sustainable way using products of natural origin, such as sugar molasses.
If we looked at the yeast under a microscope, we could find that it is made up of single-cell microorganisms of spherical shape: a 1 gram cube contains over 10 billion yeast cells. Each of these small cells, like all living organisms, must feed, reproduce and, above all, breathe, and need air for its development. The name "brewer's yeast" refers to the production methods of the past centuries (when it was obtained from beer), but today it is cultivated starting from the sugar component of molasses, a product obtained from the processing of beet and sugar cane: the yeast, in fact, is greedy for sugar. Before coming into contact with the yeast, molasses is sterilized.
At this point the yeast cells they can begin aerobic "breathing": are exposed to the action of oxygen. In addition to oxygen, molasses and nutrients (vitamins and trace elements) are added, which are used for good cell growth. These, starting to feed on molasses and other nutrients, begin the breathing process with which the demolition of glucose takes place.
At the end of the fermentation process, the yeast is washed with cold water to eliminate any residue from the molasses-based culture medium. The compound obtained is subjected to centrifugation in order to obtain the yeast cream which is then stored at a temperature of around 4 degrees.
At this point, the processing of the yeast cream depends on the type of final product to be obtained. In the case of liquid yeast, the process ends here. To obtain fresh or dry yeast, the cream is subjected to further processing, such as filtering, in the case of fresh yeast, and also dehydration, in the case of dry yeast.
As the Welovelievito.it team explains to "La Cucina Italiana", the timing depends a lot on the companies but, in general, from when you start the process at the end it takes at least a week. So let's put some patience.
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