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Why MUST we Pressure Can some Foods? - 9 Molds and Yeasts Molds are fungi that grow as silken threads and appear as fuzz on food. Some molds can produce mycotoxins that are harmful to eat. Molds thrive on the acids that are protection against bacteria. Yeasts, which are also fungi, cause food to ferment, making it unfit to eat. Fortunately, the acid in foods protects us against the growth of bacteria; however, molds and yeasts are ever present. Molds and yeasts are easily destroyed at temperatures between 140 degrees F and 190 degrees F. Boiling-water processing heats foods to 212 degrees F, more than enough to destroy the molds and yeasts without destroying the quality of the product.Bacteria Bacteria are not easily destroyed. Certain bacteria actually thrive at temperatures that destroy molds and yeasts. Salmonella is destroyed when held at 140 degrees F. Staphylococcus and aureus, or "staph," is destroyed if food is kept above 140 degrees F. Staph bacteria produce a toxin that must be destroyed by heating the product to 240 degrees F for the time specified by a tested home canning recipe. Enzymes Enzymes are present in all living things. They promote the normal organic changes necessary to the life cycle. Their action can cause food to change flavor, texture and color, making it unappetizing. Enzymes, like molds and yeasts, are easily inactivated by heat at temperatures beginning at 140 degrees F. Enzymes are inactivated by the boiling-water process. |