Abstract: 【Objective】The objective of this study is to optimize the storage conditions of citrus and provide a scientific foundation for storage warehouse improvement.【Method】Storage experiments were performed with commercially mature ‘Newhall’ navel orange fruits using three storage methods, including mechanical cold storage (Mcs), evaporative cooling ventilating storage in mountainous region (Ecvs) and ventilating warehouse storage (Vws). Environmental parameters of these storage conditions were termly detected. Meanwhile, the fruit physiological and biochemical indexes were measured with gas chromatography and infra-red CO2 analyzer. Moreover, fruit organoleptic properties were evaluated as well. 【Result】 The environment parameters under the three storage conditions changed constantly. The temperature and relative humidity in Mcs ranged from 2.1℃ to 11.2℃ and 64.4% to 99.0%, respectively. As the weather gets warm, the temperature variations of Mcs between storehouse and transport or shelf life condition were significantly different from those of Ecvs and Vws. Although the changing trends of storage parameters in Ecvs were similar to those in Vws, industry experiences revealed that the storage condition was more suitable to orange storage in Ecvs than in Vws. The concentrations of CO2 and ethylene in Mcs were significantly higher than those in Ecvs and Vws. The contents of titratable acid, soluble solid and concentration of organic acids in fruit juice decreased with the extension of storage phase. Among these storage methods, there were significant differences in the content of titratable acid and malic acid, but not in total soluble solid in fruit juice. The content of titratable acidity after 105 days of storage (DOS) remained much higher in Ecvs than that in Mcs and Vws, and similar result was observed from the changing tendency of organic acids after 65 DOS. Prior to 135 DOS, fruit firmness, content of soluble sugar and vitamin C were higher in Mcs than those in Ecvs and Vws. The content of ethanol, acetaldehyde, methanol increased sharply at 105 DOS. At 160 DOS, the ethanol content was also significantly higher in Mcs than that in Ecvs and Vws, which aggravated fruit quality derogation and accumulated abundant off-flavor components in Mcs. During the storage, the hedonic scale of fruits in Ecvs and Vws fluctuated occasionally, the peak was observed at 35 DOS, subsequently declined gradually, and reached the lowest level at 135 DOS. Among these storage conditions, the lowest hedonic scale was detected in Mcs at 160 DOS.【Conclusion】In storage warehouse, the contents of fruit organic acids, ethanol, methanol and acetaldehyde were mainly affected by gas components, especially ethylene, and temperatures differences between storehouse and transport or shelf life conditions. And these indexes are directly related to fruit quality and organoleptic properties among these storage warehouses. Fruit quality in Mcs deteriorated at 135 DOS, while fruit in Ecvs could maintain relatively high quality until 160 DOS. Moreover, Vws is more suitable for orange short-term storage, as fruit quality degenerated gradually after 65 DOS.

Key words: ‘Newhall&rsquo, navel orange (Citrus sinensis Osbeck‘Newhall’) , storage environment parameter , fruit quality , physiological and biochemical index , sensory evaluation