Water-oil displacement in prefried potatoes during freezing-thawing and reheating: A simulation of the industrial prepared dishes supply chain.

Abstract

Prefried potato is a common semi-finished product used in catering services. However, the quality changes that occur during its transition from a semi-finished to a finished dish remain unclear. This study investigated the moisture and oil content changes in prefried potatoes during freezing-thawing and various reheating processes. The results showed that the oil contents of prefried, prefried-refried, and prefried-reboiled potatoes were 2.14 %, 3.34 %, and 1.33 %, respectively. The moisture content of prefried-reboiled potatoes was higher than that of prefried and prefried-refried samples. SEM and MRI analysis revealed that freezing significantly (P < 0.05) increased porosity and promoted water-oil exchange in frozen-refried and frozen-reboiled potatoes. Ice melting contributed to reduced porosity and inhibited oil absorption in thawed-refried samples. However, there were no significant differences (P > 0.05) in moisture and oil content between frozen-reboiled and thawed-reboiled samples. This study provides new insights into the quality changes of semi-finished foods during industrial processing.