acetals

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Formed through the action of aldehydes and alcohols. Because solvents such as glycerine, alcohol, and propylene glycol contain a hydroxyl moiety, and as these solvents are used in most flavors, acetals are formed upon standing with most flavor systems. Acetals have very limited flavor use per se, as most acetals have little or no odor due to their higher molecular weight. Often acetals have off flavor like the floral character of benzaldehyde P.G. acetal, or the harsh flavor of valeraldehyde P.G. acetal. Acetals revert in slightly acid pH aqueous systems, so in most cases, when used in a final food product like an acidified food or beverage, acetals will revert back to the starting aldehyde. It is likely that the inclusion of acetals on the GRAS lists is not necessarily for their flavor characteristics, as they are not generally useful as such. However, the inclusion of chemicals and their acetals onto the GRAS list was more likely done preemptively. As a flavor sits, many reactions occur. Acetal formation is just one of these. At the time, a few companies' regulatory departments felt that all of the myriad of acetals might have to be accounted for. As this line of thinking went on, many began to realize that an insurmountable task was at hand. When we age wine, do we need to consider all of the reactions that went into the aging process? The answer is obvious. This expanded concept has never come to fruition. See Glycerine, Valeraldehyde, Benzaldehyde, Aqueous, Harsh, Floral, Beverage, Acid, Hydroxyl, Alcohol, Moiety, Dioxolanes, Ketals.1.

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