Managing weight loss in potato storages

By now, potatoes in most of the U.S. and Canada have been in storage two months or longer. The crop is at holding temperatures specific to the cultivar and use. Storages are being monitored for disease development, desired temperature, ventilation and humidity. According to Nora Olsen and Mary Jo Frazier at the University of Idaho, what isn’t as easy to see is the amount of weight loss, or shrinkage, that is occurring in storage. Stored potatoes will lose weight from respiration (carbon and water loss), transpiration (direct water loss) and disease. Transpiration water loss is the greatest factor in weight loss unless high levels of disease are present – then that becomes the greatest contributor, especially if caused by any of the water rots. In small-scale research trials, weight loss was dependent upon initial curing temperatures, and 55 to 70 per cent of the total weight loss occurred in the first 30 days. In general, about three per cent weight loss was seen in the first month. Total weight loss after five months was about five per cent. Having information on weight loss, even after the fact, can help identify ways to manage the crop in future years. More