Studies on Free Amino Acids in Sponges, Doughs, and Baked Soda Crackers and Bread

Abstract

SUMMARYFree amino acids decreased markedly during an 1%hr cracker sponge fermentation or during a 6‐hr straight dough bread fermentation. No commercial proteases were used. However, the free amino acids increased after 48 and 72 hr of cracker sponge fermentation, respectively. This suggested that the amino acids were metabolized by microorganisms during active growth at a faster rate than they were being formed from the protein by native proteases. Later, the amino acids accumulated as the rate of active fermentation and growth subsided, Pro. teolytic activities did not change with fermentation time, suggesting that microorganisms did not release additional proteases. The amino acid content of soda crackers made with a long sponge fermentation decreased during baking. Likewise, the free amino acid content of bread crust decreased during baking, while the free amino acid content of the crumb remained essentially constant.When a commercial protease was added to a soda cracker sponge and the sponge fermented for 18 hr, the free amino acids in the baked products increased to a level equivalent to that of the soda crackers made with a 72‐hr sponge fermentation without the use of commercial protease.