Utilization of snow cooling for preservation of asparagus spears
Temperature at 0-2°C and relative humidity at 95-100% are well known as ideal storage environment for green asparagus spears. The quality preservation of spears stored in a snow vault was compared with those stored in an electric refrigerator. Asparagus spears of 'Grande' and 'Gijnlim' were stored in snow or refrigerator for 0, 2, 5, 10 and 20 days, then 1) physical characteristics such as hardness, weight and surface color, and 2) internal quality such as Brix, sugar, ascorbic acid and rutin content in the spears were investigated. In terms of the storage environment, though temperature and relative humidity fluctuated largely at 3-6°C and 65-85% in the refrigerator, temperature and relative humidity during snow storage were almost stable at 0-1°C and 100%. The external appearances of 'Gijnlim' spears were preserved until the 10th day, but drying of tips was observed on the spears in both snow and refrigerator on the 20th day. 'Grande' spears stored in refrigerator wilted and turned yellow at surface of the basal part, compared with snow stored spears. No tip drying was observed on 'Grande' spears. There was no significant difference about the internal quality of the spears between the storage in snow and refrigerator in both cultivars. In 'Grande', the weight of the spears stored in refrigerator decreased dramatically compared to the storage in snow. From the view point of energy utilization and quality preservation, snow is an alternative material for spear preservation instead of refrigerator.
Nikaido, K., Jishi, T., Maeda, T., Suzuki, T., Yokota, T. and Araki, H. (2020). Utilization of snow cooling for preservation of asparagus spears. Acta Hortic. 1301, 199-206
'Gijnlim', 'Grande', postharvest quality, spear, functional substance