Evaluation of the effects of immersion thawing methods on quality of blueberries

The changes on food quality during thawing process has attracted significant attention of the frozen food industry. The effects of immersion thawing on the quality changes of blueberries were investigated. Blueberries were stored in freezing temperature for 3 days after quick freezing, and then, they were thawed using four methods: water immersion thawing (WIT), sugar immersion thawing (SIT), ultrasound‐assisted water immersion thawing (UAWIT), and ultrasound‐assisted sugar immersion thawing (UASIT). Later, texture profile, physiochemical characteristics, and sensory evaluation analysis were conducted to evaluate quality changes of blueberry after thawing. The thawing procedure employed significantly affected the quality of fruits. The shortest duration for total thawing was observed for the UASIT process. The anthocyanins and total solid content were better retained when blueberries were thawed using SIT and UASIT processes. There was no benefit of using UASIT with respect to protecting the blueberry tissue structure. However, the consumer acceptability of blueberries was not significantly difference among the four thawing conditions. Each method had advantages and disadvantages, and we should choose the suitable means according to consumer and production demand. Practical application This work was aimed at determining if there were any changes on the quality of blueberries when subjected to various thawing treatments. The sugar immersion thawing could be beneficial to nutrient retention in the freezing and thawing processing of fruits.