The Evaluation of Frozen Strawberries Quality by Studying the Kinetics Change of the Antioxidants Activity

Abstract

This paper presents the study results on quality assessment of frozen strawberries estimating the inetics change of antioxidant activity of fruit during storage. Fresh strawberries purchased from the trading system were used for the research. The study was conducted over 3 years. A total of 60 batches of strawberries harvested in Moldova were analyzed , from each batch were estimated three samples. It was appreciated the content of antioxidants: L-hidroascorbic acid, anthocyanins, total polyphenols and reducing activity of fruit. The precision of the characteristics determination for oxido-reducing state of fruit samples (K, mg AA/g SH) is obtained with the trust coefficient P< 0.01 or P<0.05, deviation error limit being ± (0.2 … 0.8) % from the average values of the K indicator. The correlation of the total hydrosoluble antioxidants content (ascorbic acid, anthocyans, polyphenols) and the oxido-reducing state indicator of the fruit (K) attests the values of the Pearson coefficient (R) within 0.88 … 1.0 and has a functional dependence. The validity of frozen fruit was demonstrated by determining the probability of quality modification of frozen strawberries.