Study On Ougan (Citrus Suavissima Hort. Ex Tanaka) Quality Changes Of Different Harvesting Time And Storage Methods

Ougan (Citrus suavissima Hort. ex Tanaka) is one of the excellent citrus varieties which have along shelf life under room temperature. During the production, it was found that harvest date andstorage methods might affect the storage properties and qualities of Ougan fruits, but there has been norelated and scientific study. Therefore, in this study, external and internal quality of Ougan fruitsharvested at different date with different size and package during the storage period was investigate toprovide important theoretical basis for harvest, storage and sales of Ougan fruits. The expected resultswill provide important basis for extending supply period of Ougan fruits, which can fill the gap of citrusmarket from April to June. The results showed that：1.Ougan fruits harvested at the late ten days of November with more than80%of coloration haveaverage fruit weight of130g，12%of total soluble sugar (TSS) and1.0%of total acid (TA). After longtime storage, the water loss and decay rate and TA (180d) was low,while TSS is high，besides, the fruithave both good appearance and taste．After long time storage,Ougan fruits harvested earlier (early ormiddle November)showed lower TSS and higher TA, and have serious dehydration problem while therate of decay was relatively low，the fruit quality and storage quality were poor；Fruits harvested later（after December）dried up faster during storage with the puffing peel problem，and the decay rate wasalso higher than the other two treatments，which needs earlier sales；Among the three harvesting timetreatments, late ten days of November is the best time for harvesting Ougan in this study.2．The harvested ougan fruits were graded by fruit size. The fruits with diameter of about60.0mmshowed better fruit quality than bigger fruits (66~75mm). Compared to bigger fruits, during storage,small to medium-sized fruit (45-65mm) showed higher TSS and lower TA，and the weight loss as wellas the rate of decay were also low, showing better storage quality. Therefore, the small to medium-sizedfruits can be considered for long time storage．Besides, the grading fruits showed lower decay rate thanthose without grading after storage. So, we suggested that size grading is necessary for ougan fruitstorage, and the bigger fruits should be marketed and consumed as early as possible after five monthsstorage,while the smaller fruits can be stored till the off-season sales to get best interest.3.During the first120days of storage, harvested Ougan fruit with individual package showedbetter fruit appearance,with bright and shiny peels and lower weight loss and decay rate, compared tothe fruits without package．However, the fruits with individual package showed poorer fruit flavor afterlonger storage, leading low commercial value.