Analysis of flavor and taste attributes differences treated by chemical preservatives: a case study in strawberry fruits treated by 1-methylcyclopropene and chlorine dioxide

Abstract

Flavor and taste attributes of fruits varied by different preservatives treatments. Changes in sugars, organic acids, amino acids as well as volatiles of strawberries treated with 1-methylcyclopropene (1-MCP) and/or chlorine dioxide (ClO₂) were evaluated during storage period in this study. Our results revealed that the decreases of tartaric acid, malic acid, citric acid, titratable acidity (TA), sucrose and soluble sugar contents were significantly inhibited by 1-MCP + ClO₂. The fructose and glucose contents of all groups remained stable and slightly increased at the last period of 10 days. However, different treatments had no influence on content of succinic acid. Moreover, the highest sweet taste (77.37 mg 100 g^-1 fresh weight) and lowest bitter taste (3.44 mg 100 g^-1 fresh weight) free amino acids (FAA) were observed in the strawberries treated by 1-MCP combined with ClO₂ treatment as compared to other treatments and control. (E)-2-hexenal was the most abundant volatile and showed a significant increase trend during strawberry storage. More interestingly, ethyl butyrate, fruit-like aroma, could be recovered in content by 1-MCP, ClO₂ alone and their combination treatment. Compared with other treatments, the significant different flavor in ClO₂ treatment was identified by principle component analysis. In addition, methyl hexanoate and 4-methoxy-2,5-dimethylfuran-3(2H)-one (DMMF) were the major factors that affected the volatile organic compounds (VOCs) of strawberries through the whole storage. Taken together, 1-MCP coupled with ClO₂ could be a complex preservative to maintain strawberries quality by regulating the flavor and taste attributes.

Keywords: 1-MCP; ClO2; Flavor; Strawberry; Vocs.

Fig. 1

Effect of 1-MCP and/or ClO₂ on storage index of strawberries during storage: a Firmness; b Total soluble solid (TSS); (c) Titratable acidity (TA); (d) Soluble sugar. Each treatment involved the three replicates. And the standard deviations of the averages were represented by bars. Different uppercase letters indicate significant difference within a group at a same day, different lowercase letters indicate significant difference between groups (P < 0.05)

Fig. 2

Effect of 1-MCP or/and ClO₂ on organic acid metabolism of strawberries during storage: a Tartaric acid; b Malic acid; c Citric acid; d Succinic acid. Each treatment involved the three replicates. And the standard deviations of the averages were represented by bars

Fig. 3

Effect of 1-MCP, ClO₂ alone and the combination on organic acid metabolism of strawberries during storage: a Fructose; b Glucose; c Sucrose. Each treatment involved the three replicates. And the standard deviations of the averages were represented by bars