Fresh Purple waxy corn maintains good flavor qualities under low temperature storage: a comprehensive evaluation...

This study focused on the alterations of nutrition, texture and flavor of fresh waxy purple corn during storage at -20 °C after quick freezing. The nutritional characteristics include anthocyanin, total sugar and starch content; changes in flavor properties were tracked using E-nose, E-tongue, GC-IMS and GC-MS techniques. The results showed that the contents of anthocyanin and total sugar decreased gradually, and the loss rate of anthocyanin reaches 56.67% at 60d. However, there was no significant change in texture properties within 45 days. Through flavor analysis, the cold storage enhanced the acidity and saltiness attributes and weakened the flavor profiles related to aromatic compounds. Furthermore, new volatile compounds such as 1-nonanol, 2-octanone, n-octanol and n-octanal etc. were produced when frozen to 45 d; in comparison, several of the original aromatic compounds disappeared on day 60, including linalool (floral), 5-dimethyl-3(2H) furanone (strawberry-like), and phenylethanol (rose-like). At the same time, the content of some volatile compounds with bad flavor gradually increased, such as ethanol、heptan-1-ol and benzaldehyde. In general, the flavor and nutritional quality of fresh purple glutinous corn remained good within 45 days, and began to deteriorate when it was frozen to 60 days.