Acids in wine ripened grapes. While concentration varies among grape varieties, it is usually found in higher levels with red wine grapes. The acid is created as a byproduct of the metabolization of nitrogen by yeast cells during fermentation. The combination of succinic acid with one molecule of ethanol will create the ester mono-ethyl succinate responsible for a mild, fruit aroma in wines. Acidity is highest in wine grapes just before the start of "veraison", which ushers in the ripening period of the annual cycle of grape vines. As the grapes ripen, their sugar levels increase and their acidity levels decrease. Through the
The Fox and the Grapes The Fox and the Grapes The Fox and the Grapes is one of the Aesop's fables, numbered 15 in the Perry Index. The narration is concise and subsequent retellings have often been equally so. The story concerns a fox that tries to eat grapes from a vine but cannot reach them. Rather than admit defeat, he states they are undesirable. The expression "sour grapes" originated from this fable. The fable of The Fox and the Grapes is one of the few which feature only a single animal protagonist. There are several Greek versions as well as one in Latin by