Deterioration model for the assessment of longan senescence and decay

Abstract

The correlation of browning index (BI) to decay parameters was determined using total soluble solid content (TSS), ethanol and ethanol/TSS ratio. Longan fruits were harvested traditionally and compared with precooling technique. It was found that longan fruit, harvested without cooling, exhibited better colour retention, and less off-flavour production. All parameters except TSS gave a good correlation with storage time. The relations of BI to ethanol and ethanol/TSS were also observed and high regression coefficients were also found (R2>0.80). The data all fitted well with linear regressions, thus giving the model to predict storage time of the longan fruit after harvest as: (D=2.14x-0.6, R2= 0.75) where x = BI×(E/T).