PENGARUH MACAM DAN KADAR KITOSAN TERHADAP PEMATANGAN DAN MUTU BUAH SAWO (Manilkara zapota (L.) van Royen)

The aim of this research was to study the effect of two different chitosans and their concentrations on ripening and quality of sapodilla and to determine the optimum levels of shrimp and crab chitosan able to inhibit ripening and maintain the quality of sapodilla. The research was conducted at the Laboratory of Horticulture and the Integrated Research and Testing Laboratory, Gadjah Mada University from July to December 2012. The research was carried out using 2x6+1 factorial design arranged in Randomized Completely Block Design (RCBD) with 3 blocks as replications. The first factor was kind of chitosan i.e. shrimp and crab chitosan. The second one was concentrations of chitosan i.e. 0.5%, 1%, 1.5%, 2%, 2.5% and 3%. Untreated sapodilla fruit served as control. The collected data were analyzed by analysis of variance (Anova) using level of significance of α = 5%. Whenever the significant differences among treatments were observed, further analysis was carried out by applying Duncan�s Mutiple Range Test (DMRT) of α = 5%. The orthogonal contrast test was also performed to compare the mean values of chitosan treatment with the control. The results showed that chitosan inhibited ripening and lengthened storage life of sapodilla fruit for 2 � 3 days. The effect of shrimp chitosan was not significantly different from that of crab chitosan. Chitosan did not change the quality of sapodilla fruit when ripe, except on visual quality rating (VQR) which was lower than VQR of the control. The optimum concentration of chitosan for inhibiting ripening and lengthened storage life of sapodilla fruit was 2.6%