Cryogenic freezing preserves the quality of whole durian fruit for the export market

Abstract

Durian (Durio zibethinus cv. Musang King; D197) is a popular durian cultivar due to its thick flesh and strong sweet taste. The high market demand and shortage of out-of-season supply contribute to the increase in durian price. Other than that, durian has a short storage life, and to prolong the storage life of Malaysian durian, freezing treatment has been applied. This study was conducted to evaluate the effect of freezing methods on the physical and sensory qualities of the whole durian. The freezing method included conventional (at -18°C) and cryogenic freezing (-110°C). The frozen durian was thawed and evaluated after 12-hours, 24-hours, and 36-hours for external and internal quality, dehiscence incidence, and physicochemical parameters (pulp colour, soluble solids content, total titratable acidity, and percentage of moisture) during 36-hours storage. The results showed that conventional freezing at -18°C adversely affected the quality of durian. The fruits were severely dehiscent due to the slow freezing rate. Later, the freezing injury became obvious when exposed to ambient temperature. In comparison, during cryogenic freezing durian fruit froze rapidly without any dehiscence. The freezing methods used in this study did not affect the physicochemical parameters of durian pulp during 36-hours storage. Cryogenic freezing is noted to be a promising method for preserving the quality of durian fruit, thus extending the storage life for market expansion.