The Maturity Index of Fruit for High Aroma Components of Processed Liqueur of ‘Nanko’ Japanese Apricot (Prunus mume Sieb. et Zucc.)

Abstract

In this study, we attempted to identify the maturity index of fruit for high aroma components of processed Japanese apricot liqueur (ume liqueur) of ‘Nanko’ Japanese apricot (Prunus mume Sieb. et Zucc.). Aroma components, total decalactone, ethyl butyrate, and butyl acetate, in ume liqueur were significantly related to the skin color b* value and fruit firmness of raw material fruit. The ume liqueur made from fruit which showed below 34.5 in the skin color b* value of raw material fruit contained each aroma component below 50 μg·L⁻¹ in 2008 and below 100 μg·L⁻¹ in 2009. The ume liqueur made from fruit with above 0.98 kg in fruit firmness of raw material fruit contained each aroma component below 50 mg·L⁻¹ except for one sample in 2008, and below 100 μg·L⁻¹ in 2009. The ume liqueur made from the fruit that showed an above 34.5 skin color b* value and below 0.98 kg fruit firmness value had significantly higher levels of total decalactone, ethyl butyrate, and butyl acetate than the other ume liqueur. Even though the ume liqueur was made from fruit stored within six days at 20°C, the skin color b* value and fruit firmness of raw material fruit were significantly related to the content of aroma components in ume liqueur. These results suggested that the skin color b* value and fruit firmness were available as indexes of aroma components in the ume liqueur made from ‘Nanko’.