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Wade E

Jul 3, 2006
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Here is another quote from Tim Vandergrift about Potassium sorbate.

"Okay, having identified that you simply have a general sense of 'what's it there for', I'll let you in on the real truth behind sorbate.

We include it in the kit to prevent the growth of certain classes of bacteria and moulds. It also suppresses many different indigenous yeast strains. As a manufacturer, we're faced with the reality that many of the people who use our kits, especially for the first time, may not understand the importance of stringent sanitation protocols. We have twenty to forty cases a week where people fail to add yeast, so in order to obviate product failures due to the introduction of spoilage organisms in the user's hands, we specify the use of sorbate, and include it in the kit.

Sorbate is harmless, odourless, tasteless, and indetectable in the amounts we include in the kit. No one has the capacity to detect a couple of grams of sorbate dissolved in 23 litres of wine, and it has no effect on human health (well, almost none: it's used in treating certain types of gatritis caused by foreign bacteria in the gut).

This is from a monograph from one of our suppliers:

Potassium sorbate can restrain effectively the activity of mould, yeast and aerophile bacteria. Restrain growth and reproduction of the pernicious micro oraganism as pseudomonas, staphylococcus salmonella action to restrain growth is more powerful than killing. Meanwhile, it can not restrain useful microoraganim growth as Anaerobic spore-bearing bacilli, acidophil therefore to lengthen food store period and remain food original flavor. The preservative efficiency of sorbic acid (potassium sorbate) is 5-10 times sodium benzoate.

When dissolved in water, potassium sorbate ionizes to form sorbic acid which is effective against yeasts, molds, and select bacteria, and is widely used at 250 ppm to 1000 ppm levels in cheeses, dips, yogurt, sour cream, bread, cakes, pies and fillings, baking mixes, doughs, icings, fudges, toppings, beverages, margarine, salads, fermented and acidified vegetables, olives, fruit products, dressings, smoked and salted fish, confections and mayonnaise.

Sorbic Acid (also called chemically 2,4-Hexadienoic acid ), a white crystalline powder or granule form for dust free, is an unsaturated fatty acid which has two double bonds in conjugation that is, two double bonds separated only by one single bond. It and its salts (potassium sorbate, calcium sorbate ; its salts are used according to differences in solubility.) are used as preservatives in wide range of food products as well as in their packaging materials, since they are characterized by their broad effectiveness to inhibit molds, yeast, and many bacteria growth in food. Potassium sorbate, white to slightly yellow crystalline powder, is the potassium salt of sorbic acid and is much more soluble in water than the acid. Potassium sorbate will releases back sorbic acid if dissolved in water. It is effective up to pH 6.5 but effectiveness increases as the pH decreases. The lower the pH value of the product the lower amount of Sorbic Acid or Potassium Sorbate is needed for preservation. Its industrial applications include use in coating industry to improve gloss and in rubber industry.

Potassium sorbate is used as a a mold, bacterial and yeast inhibitor and as a fungistatic agent in foods. It is also used in cosmetics, pharmaceutical, tobacco and flavoring products. In wines, it is to prevent the secondary fermentation of residual sugar. It is used in coating to improve gloss. It is used as an intermediate to manufacture plasticizers and lubricants.. It is used as an additive in rubber industry to improve milling characteristics.

Chemical Formula: CH3CH:CHCH:CHCOOK