不同预冷方式对茭白采后降温速度和贮藏品质的影响

为筛选茭白的适宜预冷方式,采用4种不同方式(冷库套袋、冷库无袋、冰水套袋、冰水无袋)预冷茭白并进行贮藏,测定不同预冷方式下茭白中心温度的降温速度,以及贮藏期间白度值、硬度、还原糖、可溶性蛋白质等品质的变化规律。结果表明,冰水无袋预冷方式降温速度最快,降至预冷终温4℃仅需96 min;而冷库套袋、冷库无袋、冰水套袋预冷方式则分别需要1 117、114、375 min;采用冰水无袋预冷方式处理的茭白易滋生微生物,加重贮藏后期腐烂的发生,而冰水套袋预冷处理的茭白,在贮藏过程中可维持较高的可溶性固形物(TSS)和可溶性蛋白质含量,并降低失重率。因此,冰水套袋预冷处理是采后茭白适宜的预冷方式。

Effects of different pre-cooling methods on cooling speed and storage quality of postharvest water bamboo shoot

In this study, four different ways, i.e. packaged in bag and cooled in cooling room (PCCM), unpackaged in bag and cooled in cooling room (UCCM), packaged in bag and cooled in ice water (PCIW), unpackaged in bag and cooled in ice water(UCIW) were used for pre-cooling and storage of water bamboo shoot. The suitable precooling way was selected through measuring the cooling speed of the central temperature of water bamboo shoot under different precooling ways, as well as the changes of the whiteness value, hardness, reducing sugar and soluble protein during storage. The results showed that the cooling speed of UCIW group pre-cooling was the fastest, and it only took 96 min to reach the final precooling temperature of 4 ℃, while the precooling methods of PCCM, UCCM, PCIW needed 1 117, 114 and 375 min, respectively. Water bamboo shoot treated by UCIW pre-cooling was easy to grow microorganism, which aggravated the occurrence of rot in the later stage of storage, while the content of total soluble solid(TSS)and soluble protein of water bamboo shoot treated by PCIW pre-cooling could keep high content of TSS and soluble protein during storage, and the weight loss rate could be also reduced. Therefore, PCIW treatment was a suitable pre-cooling method for postharvest water bamboo shoot.