On food and cooking the science and lore of the kitchen ( PDFDrive ) 1007

the amount of solid material in a given volume and making the bread or cake less dense, more light and tender Yeasts Humans have been eating raised breads for 6,000 years, but it wasn’t until the investigations of Louis Pasteur 150 years ago that we began to understand the nature of the leavening process The key is the gasproducing metabolism of a particular class of fungus, the yeasts The word “yeast,” however, is as old as the language, and first meant the froth or sediment of a fermenting liquid that could be used to leaven bread Food Words: Leavening and Yeast Leavening comes from an Indo-European root meaning “light, having little weight.” Related words from the same root include levity, lever, relieve, and lung Yeast comes from a root word that meant “to seethe, boil, bubble over.” This derivation underlines the way in which fermentation seemed to be a kind of cooking of the cereal gruel, a transformation from within The yeasts are a group of microscopic single-celled fungi, relatives of the mushrooms More than 100 different species are known Some cause human infections, some contribute to food spoilage, but one species in particular — Saccharomyces cerevisiae, whose name means “brewer’s sugar fungus” — is put to good use in both brewing and baking For much of human history, yeast was simply recruited from the grain surface or supplied by an earlier piece of dough, or obtained from the surface of beer brewing vats Today strains especially selected for breadmaking are grown on molasses in industrial fermentation tanks Yeast Metabolism Yeasts metabolize sugars ... seethe, boil, bubble over.” This derivation underlines the way in which fermentation seemed to be a kind of cooking of the cereal gruel, a transformation from within The yeasts are a group of microscopic... The yeasts are a group of microscopic single-celled fungi, relatives of the mushrooms More than 100 different species are known Some cause human infections, some contribute to food spoilage, but one species in particular — Saccharomyces... sugar fungus” — is put to good use in both brewing and baking For much of human history, yeast was simply recruited from the grain surface or supplied by an earlier piece of dough, or obtained from the surface of beer brewing vats