Influences of different freezing and thawing methods on the physico-chemical, flavor, and sensory properties of durian puree (cv. Monthong)

摘要

Influences of air blast freezing (AF method), cryogenic freezing (CF method), and freezing by direct immersion in liquid nitrogen (LN method) and thawing by refrigerator (RG method) and microwave (MW method) on qualities of durian puree (cv. Monthong) were investigated. After the freezing process and frozen storage, all frozen samples greatly tended to change physico-chemical parameters; drip loss (7.94-97.98%) and a* (17.45-69.75%), flavor properties; aldehydes (1.35-136.99%) and alcohols (4.86-107.22%), and sensory scores; overall flavor (4.76-26.89%) and overall liking (4.48-22.19%) from zero months of storage. However, the lowest change in almost all parameters resulted from using the CF method. Furthermore, at zero months of frozen storage, the MW method changed some physico-chemical properties less than the RG method, but there were no differences in any parameters between both methods after 6 months. Moreover, during frozen storage the MW method developed a new volatile compound, namely 3-methylbutanal, which presented an off-flavor.