VACUUM IMPREGNATION AND NUTRITIONAL ENRICHMENT IN PRETREATMENT OF FROZEN APPLE (ROYAL GALA)
Vacuum impregnation (Ⅵ) with nutraceticals was used as a pretreatment of freezing apples (Royal Gala) for improving quality of frozen apple and introducing nutraceuticals into the fruits. Apple samples were immersed in diluted high fructose corn syrup (HFCS) (20 ％w/w or 50 ％ w/w) integrated with either calcium gluconal (CG) or zinc lactate (ZL). Vacuum pressure of 50mm Hg was applied for 15 min, and then atmospheric pressure was restored for 30 min while samples remained in the solution. Mineral content and physicochemical properties of the apples immediately after Ⅵ were determined. Results indicated that about 15％ to 20％ DRI (Daily Reference Intake) of calcium and above 40％ zinc could be obtained in 200g of frozen apples depending on the Ⅵ conditions. Ⅵ treatments in 20％ w/w solutions had little effects on the physiochemical properties of Ⅵ apples. But 50％ w/w solutions could partially remove moisture before freezing, cause a significant reduction in drip loss, and overcame the tissue damage induced by the freeze-thawing process. The Ⅵ pretreatment using 50％ HFCS solution increased the maximum compression force (firmness) 79％ to 258％ and reduced the drip loss 57％ to 60％ in frozen-thawed apple columns. Calcium gluconal in the Ⅵ solutions further increased the firmness of thawed apple columns. Zinc lactate improved color stability of apples during the impregnation and freeze-thawing process.
vacuum impregnation calcium zinc pretreatment of freezing Gala apple
J.XIE Y.ZHAO
College of Food Science, Shanghai Fisheries University, Shanghai, 200090, P.R. China Department of Food Science and Technology, Oregon State University, Corvallis, OR 97331
国际会议
The 22nd International Congress of Refrigeration(第22届国际制冷大会)
北京
英文
2007-08-21（万方平台首次上网日期，不代表论文的发表时间）