Pre-cooling of Agricultural Products
Overview
Precooling refers to the rapid removal of field heat shortly after the harvest of a crop. Field heat can be defined as the difference in temperature between the temperature of the crop harvested and the optimal storage temperature of that produce. In general the temperature should be cooled down till it reaches 88% of the existing difference in temperature and its optimal storage temperature. Field heat should be removed as fast as possible since, for most produce, an hour delay at field conditions of about 35°C will lead to a loss in shelf-life of about 1 day – even at optimal storage conditions (National Horticulture Board, 2010; Thompson, n.d.). Nevertheless, due to biological factors, the importance of rapid pre-cooling varies. According to the Indian Board of Horticulture[1], especially grapes, mandarins, berries, cherries, leeches, melons, stone fruits, sapotas, okra, tomatoes, capsicum, chilli peppers, eggplant, cucumbers, green beans, peas, and spinach should be rapidly pre-cooled, whereas other, less perishable produce is made up of mangoes, papaya, guava, green bananas, pomegranates, radish, cabbage, cauliflower and carrots.
More detailed information about adequate pre-cooling methods for various fresh produce items can be found under: http://www.ba.ars.usda.gov/hb66/contents.html
According to the FAO, precooling is “amongst the most efficient quality enhancements available” and is regarded “as one of the most value-adding activities in the horticultural chain”. Precooling benefits include:
References
- ↑ National Horticulture Board (2010) Cold Storage for Fresh Horticulture Produce Requiring Pre-cooling before Storage. Haryana: Cold Chain Development Centre National Horticulture Board
