Effects of postharvest sodium silicate treatment on quality and volatile flavor components of apricot fruit during storage

Silicates, generally regarded as safe substances, have been widely used to control postharvest diseases of fruit and vegetables, but very little work has been done on their effects on fruit quality. The apricot fruit (Armeniaca vulgaris Lam. cv. Lanzhou Dajie) was treated with 10 mmol/L sodium silicate for 10 min and stored at room temperature (22±2℃) to investigate the effect of silicon treatment on apricot fruit quality, especially the volatile compounds. The results indicated that treatments retarded flesh firmness decrease and alleviated decay. After 9 days of storage, the treated fruits showed 1.95 times for firmness and 58% for rotting rate of control fruits. The silicon treatments still remained higher content of soluble solids, vitamin C and delayed the decrease of titratable acidities, but there was no significant difference of content of total sugars between the two groups. More than 100 kinds of volatile compounds were identified with solid phase microextraction-gas chromatography-mass spectrum (SPME-GC-MS) from the fruits. Sodium silicate treatment significantly reduced the emission of total amount volatile compounds of apricot fruits during storage, and enhanced the amount of aldehydes, terpenoids and β-ionone and lowered amount esters throughout the investigation period in comparison with that of control. Compared with the control, the sodium silicate treatment can maintain postharvest quality of apricot fruit better and is a feasible way to keep apricot fruit fresh.