Abstract
In a previous work we learned by organoleptic evaluation that the aroma of 'Koromo of Tempura' was formed when wheat flour was fried with corn oil, but when wheat flour was replaced by wheat starch or when corn oil was replaced by silicone oil, the aroma was not formed.
In order to determine the origin of the aroma, wheat flour was fractionated into three parts, wheat starch, gluten and water soluble components. These fractions were fried with olive oil, separately or in combination, and the aroma resulted from the deep frying was analyzed organoleptically.
It was detected that the aroma was formed by combined water soluble components and gluten. Among the water soluble components amino acid was considered to be responsible for the aroma. Therefore various amino acids were added into the mixture of starch and gluten and the batter was deep-fried with olive oil. It was discovered that either glutamic or aspartic acid was responsible for the formation of the aroma.
The effects of oils on the production of the special aroma were also investigated. The olive oil was substituted by chemically synthesized pure triolein to which various other oil materials were added.
It was observed that the aroma became much closer to that of 'Koromo of Tempura' when 5% Me. linoleate was added to triolein. Unsapponifiable matters, such as phytosterin, added to triolein had no such effect on the aroma.
