Effects of CaCl2 and AsA treatments on quality and browning in fresh-cut apple.

【Objective】 The changes of quality and browning of the fresh-cut apples,the physiological roles of exogenous ascorbic acid (AsA) and calcium chloride (CaCl2) were studied for screening of an ideal preservative. 【Method】 Ripening 'Fuji' apple fruits were used as materials and peeled,cored,and then cut into slices about 1mm; after soaked for 5 min in distilled water,1.0% AsA and 1.0% CaCl2 aqueous solution,wiped the surface water,then put in culture vessel under 25 ℃,and at 0,0.25,0.5,1,2,4,6,8,10,12 h,the browning index and the rate of weigh loss were surveyed,the contents of total soluble sugars,total titratable acids,ascorbic acid (AsA),total phenols and malondialdehyde (MDA) were analyzed,and the polyphenol oxidase (PPO) and peroxidase (POD) activities were detected. 【Result】 The quality and physiological characteristics of the fruit slices soaked in distilled water were changed dramatically,flesh browning was rapid and serious,water and other volatile material released largely,the content of total soluble sugars,total titratable acids,AsA and total polyphenols decreased,the ratio of sugar and acid increased,the activities of PPO and POD rose rapidly. The content of MDA increased first and then decreased. 1.0% AsA and 1.0% CaCl2 treatment could effectively delay the process of flesh browning,reduced browning degree,inhibited decreasing of water,volatile substances,total soluble sugars,total titratable acids,ascorbic acid and total polyphenols,delayed sugar/acid ratio increase,as well as PPO,POD activities in the peak arrival,the content of MDA increased. In general,the treatment of 1.0% CaCl2 was better. In addition,a quality evaluation system of fresh-cut product was initially established. Varieties with high content of soluble solids,total soluble sugar,total titratable acids and phenolic substances,low volatile matter loss rate,and browning-resistance are good apple varieties for fresh-cut apples processing.【Conclusion】 1.0% CaCl2 is a better preservative reagent and browning inhibitor in fresh-cut apples.