In order to determine optimal freezing methods for vegetable soybean

effect of three freezing rates of ﹣35 ℃ with 8 m/s wind

﹣35 ℃ and ﹣18 ℃ on freezing temperature curve and the quality index changes of frozen vegetable soybean stored at ﹣18 ℃were investigated. The results showed that freezing at ﹣35 ℃ with 8 m/s wind had best freezing speed. Under the condition

the zone of maximum ice crystal formation in vegetable soybeans took the shortest time of 40 s

while freezing at ﹣35 ℃ and ﹣18 ℃ took about 6 minutes and 1 h

respectively. Freezing methods had significantly influence on the texture

drip loss rate

membrane permeability

MDA content

chlorophyll content

Vc content. In general

the lower temperature and faster freezing speed during freezing

the obviously lower speed of quality deterioration during storage. Quality of soybean frozen at ﹣35 ℃ with 8 m/s wind was significantly better than that frozen at ﹣18 ℃

so freezing at ﹣35 ℃ with 8 m/s is suitable for the rapid freezing of vegetable soybean.