THE PRODUCTION OF LINOLEIC AND LINOLENIC ACID HYDROPEROXIDES DURING MASHING

To clarify the lipid oxidation mechanism during wort production, the p roduction of hydroperoxides during mashing was studied using a chemilu minescence-HPLC method. Free linoleic and linolenic acids increased du ring mashing and their rates of increase were significantly accelerate d at 65-degrees-C, indicating that lipase acts during mashing. Linolei c and linolenic acid hydroperoxides increased just after mashing-in, r eached a maximum level after 10 min at 65-degrees-C, and then decrease d. When malt with higher lipoxygenase activity was used or the mashing was started at a lower temperature, the production of both hydroperox ides significantly increased. When an inhibitor of lipoxygenase was ad ded to the mash just before mashing, the production of both hydroperox ides drastically decreased. Therefore, it is suggested that lipoxygena se and lipase in malt plays an important role in the production of lin oleic and linolenic acid hydroperoxides during mashing.