Sourdough-type bread from waste bread crumb

Optimal conditions for sourdough production from waste bread containing sugar were studied. Using a dough prepared with 50% white bread crumb in water instead of 35% crumb, high levels of acidity were formed at 35 degrees C with a commercial lyophilized starter containing Lactobacillus plantarum. The effect of temperature (25 or 35 degrees C) on titratable acidity development was equivalent to crumb concentration (35 or 50%). Cell growth stopped after 12-24 h but acid production continued for more than 48 h. Best results were obtained with whole wheat bread crumb followed by sweet-type crumb (about 8% sugar, dry basis) and white bread crumb. Two commercial sources of Lactobacillus plantarum, one meat starter and one bread starter, were screened based on acid production in fermented bread crumb. (C) 1999 Academic Press.