As there is very little acid produced by the yeast fermentation, lactic, acetic or citric acid is often added to the fermentation stage to stabilize the process.
en.wikipedia.org Organic acids are used widely as antimicrobials in food products, e.g. lactic acid, citric acid, acetic acid, and their salts, either as ingredients, or as disinfectants.
en.wikipedia.org When citric acid is added, it is always done after primary alcohol fermentation has been completed due to the tendency of yeast to convert citric into acetic acid.
en.wikipedia.org Sodium chloride and sucrose elicited the largest response in the rat gustatory cortex in rats, whereas citric acid causes only a moderate increase in activity in a single neuron.
en.wikipedia.org The fruit does yeoman's works through the albedo of white grapefruit and a citric acid shell.
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