Final answer:
Calcium propionate (A) is the preservative often used as a fungicide and mold preventative in bakery products. As a chemical preservative, it inhibits microbial growth by interfering with essential enzymes and lowering intracellular pH within molds.
Step-by-step explanation:
The preservative often used as a fungicide and mold preventative in bakery products is Calcium propionate (A). Calcium propionate is a chemical preservative that is used to inhibit microbial growth, specifically to control the growth of molds and yeast in bakery goods, addressing the concern of spoilage and extending the shelf life of the products. The chemical preservative is nontoxic, does not affect the flavor of the food, and is readily metabolized by the human body.
Calcium propionate works by inhibiting enzymes that are vital for the growth of the microorganisms and by decreasing the intracellular pH within the mold cells, which makes the environment less hospitable for their survival. It is effective at a higher pH compared to other preservatives like sorbic acid or benzoic acid, making it suitable for use in baked goods.
For example, the balanced chemical equation for the reaction of propionic acid (CH₃CH₂CO₂H) with calcium hydroxide [Ca(OH)₂] to produce calcium propionate would be:
2CH₃CH₂CO₂H + Ca(OH)₂ → (CH₃CH₂COO)2Ca + 2H₂O