Long-term storability of potato tubers in aspect of biochemical changes and overall quality index affected by different packaging materials in refrigerated and non-refrigerated storage


Long-term storage of tubers in refrigerated and non-refrigerated storage induces sprouting and other degradative quality changes, thus making them unacceptable for consumption. There are already known effects of packaging materials on storability of fresh produce while optimization of package with respect to temperature for shelf life enhancement of tubers is still needed in the case of deficient storage conditions. Therefore, we investigated the combined effect on post-harvest quality parameters of various packaging materials, viz. polypropylene (PP), perforated polypropylene (PP(P)), low-density polyethylene (LDPE), perforated low-density polyethylene (LDPE(P)), brown gunny sacks (BS) and white nylon gunny sacks (WS), in refrigerated storage temperature of 8 °C and non-refrigerated storage temperature of 25 °C. Sprout and spoilage appearance, weight loss, firmness, colour difference, sucrose, reducing sugars, vitamin C, total phenolic content and DPPH-antioxidant activity and overall quality index were evaluated in stored potato tubers. Lower weight loss in LDPE and PP bags was observed along with the higher retention of total phenolics and antioxidant activity of tubers. The presence of perforations resulted in higher firmness of potatoes at both the temperatures. Colour changes were determined by the temperature effects rather than packaging. The study also established some physicochemical quality indicators based on the cut-off points produced from overall quality index evaluated using the sensory attributes of stored potatoes. Overall, PP(P), LDPE(P), BS and WS can be recommended for long-term storage, while PP and LDPE can be used as an option for short-term storage.