Development of vinegar extract from the waste peels of Shiikuwasha

Abstract

In this study, vinegar extract was produced from the waste peels of Shiikuwasha, which contains characteristic ingredients such as polymethoxyflavones (PMFs) and is applicable for commercialization as a seasoning product. The results of this study are: (1) After the seeds and segment membranes were removed from the residual substances from juice production, the peels were extracted using spirit vinegar without drying, resulting in a vinegar extract contained PMFs. Also, the vinegar extract was characterized by minimal amounts of limonin and low bitterness. (2) A ratio of 20% (w/w) waste peels to 80% (w/w) spirit vinegar was employed, and the resultant vinegar extract contained 7.5 mg/100mL nobiletin. The optimal extraction process was performed 4-5 times in ten seconds. (3) During storage at ambient temperature, the PMFs content was stable, but monoterpenes decreased sharply and monoterpene alcohols decreased gradually.