Effects of ultrasound-assisted thawing on the quality of edamames [Glycine max (L.) Merrill] frozen using different freezing methods

The effects of different freezing and thawing methods on the physicochemical indices and nutritive value of edamame [Glycine max (L.) Merrill] were investigated. Air-blast freezing had less of an impact on the drip loss, color, chlorophyll and ascorbic acid contents, and textural hardness of frozen shelled edamames. Ultrasound-assisted thawing significantly (p < 0.05) shortened thawing time, compared to water immersion thawing. Ultrasound-assisted thawing at a 900 W power level showed the best retention of ascorbic acid and chlorophyll, and original hardness, and minimized the drip loss of thawed samples. Ultrasonic assisted thawing at a power level of 1,200 W caused the most pronounced loss of ascorbic acid. A combination of fast air-blast freezing and ultrasound-assisted thawing at a power level of 900 W most effectively retained ascorbic acid and chlorophyll, minimized drip loss, and maintained the textural hardness of shelled edamame samples.