In order to control the formation of white sediment on the surface of salted Chinese olive (WSSCO), improve the product quality and promote the absorption of nutrients, the effects of two factors, variety and salting, were investigated. Three varieties, Raoping, Huiyuan and Changying, were selected and the turbidity meter was used for evaluation of the salting conditon. The results showed that there were little difference for the main components and mineral elements among three varieties. Raoping had the highest contents of polyphenols and soluble protein,especially the polyphenol content in peel was(2.675 ±0.035)%(wet weight). Polyphenols and soluble protein might be the precursors of WSSCO. H+ could change the protein hydrophobicity to affect the combination of protein and polyphenols. When pH of salt solution was 2.25~2.50,the production of WSSCO was minimum. The high concentration salt could reduce the protein solubility,while sodium metabisulfite could protect polyphenols and destroy protein structure, thus preventing their combination. Therefore,with the increase of salt and sodium metabisulfite concentration,the WSSCO content decreased. The high concentration of Ca2+ could combine with phenolic hydroxyl to form insoluble compounds. When the Ca sup>2+concentration was below 2.5 g/L,there was no effect on WSSCO formation,while the concentration was more than 2.5 g/L,it could promote the formation of WSSCO. So, regulating saline conditions could inhibit the formation of WSSCO.
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