Vacuum Impregnation Pretreatment with Pectinmethylesterase to Improve Firmness of Pasteurized Fruits
Résumé
ABSTRACT: Vacuum impregnation allows replacing the occluded air present in fruits by a solution. Apples, strawberries, and raspberries were infused in a solution of pectinmethylesterase (PME) and calcium chloride (CaCl 2 ) either by using this technology or by classical infusion. The vacuum pretreatment limited the loss in fruits firmness following pasteurization. The influence of PME and CaCl 2 concentrations in the vacuum impregnation solutions on the calcium content, the PME activity and the firmness of pretreated strawberries was studied: the firmness of strawberries was maximal after impregnation in solutions containing a threshold concentration of PME and/or calcium. The synergistic action of PME and calcium used in the vacuum impregnation solution was significant.