Biochemical response of sweet potato to bemul-wax coating combined with calcium chloride treatment during ambient storage

Sweet potato (Ipomoea batatas Linn) tuber is a very nutritious but highly perishable crop that is subject to high wastages due to non-availability of appropriate storage techniques. This work assessed the effectiveness of treating the tubers with calcium chloride dip (CCD), bemul-wax (B-wax) and their combinations (CCD/B-wax) at ambient storage conditions (24.9 ± 4.0°C and 44.6 ± 18.4% RH). Some biochemical parameters of each treated sample were assessed and compared with the control for 20 days storage period. There were significant reductions (P < 0.05) in weight loss by B-wax and CCD/Bwax. CCD and CCD/B-wax caused significant reductions in pH, total amino acid and pectin esterase. Also, all the treatments caused significant reductions in ascorbic acid, phenylalanine ammonia lyase, αAmylase and alcohol dehydrogenase activities. There were significant reductions in polyphenol oxidase activity by B-wax. In conclusion, while all the treatments proved to be effective to varying degrees, CCD/B-wax seemed to be the most effective in preventing spoilage in the tuber.