Effectiveness of non-chlorine sanitizers in enhancing quality and shelf life of tomato in Bangladesh, Cambodia and Nepal

D.M. Gautam, K.M. Tripathi, C. Mouylin, B. Buntong, M.A. Rahman, M.L. Bari, A.L. Acedo, W. Easdown, J.A. Hughes, J.D.H. Keatinge
Chlorine is the most widely used sanitizer for fresh vegetables and fruit. However, it reacts with organic matter in the produce to form highly carcinogenic trihalomethanes; consequently, chlorine use is being phased out in several countries. This research examined the feasibility of using hydrogen peroxide (H2O2) and calcinated calcium (CCa) in enhancing the quality of tomato in Cambodia and Nepal; the Bangladesh trials used only CCa, which was the most promising treatment found in an earlier study. Results of the Cambodia trials showed CCa to be more promising than H2O2, which induced fruit surface browning. The effect of CCa in reducing total bacterial counts was comparable to that of chlorine right after treatment. This was sustained after 5 days under ambient conditions in modified atmosphere packs (MAP), whereas chlorine-treated fruit had increased bacterial counts, similar to water wash. CCa also reduced weight loss and increased shelf life of the fruit. CCa at 0.01% was sufficient to yield these effects. In the Bangladesh trials, 0.01% CCa significantly increased fruit shelf life both under ambient conditions and in MAP. Use of cold CCa had no added benefit. CCa increased total soluble solids (TSS), particularly in ambient-stored fruit, but had no noticeable effect on fruit weight loss or firmness. In the Nepal trials, bacterial and fungal loads decreased after treatment with H2O2 and CCa. Microbial load increased sharply in the control to more than 8 log CFU g‑1 from less than 5 log CFU g‑1 after treatment and after 5 d in MAP. CCa and chlorine suppressed microbial growth and maintained microbial loads of 4 log CFU g‑1. Furthermore, CCa reduced rot incidence, lowered weight loss, and maintained higher vitamin C content of the fruit. The results show the potential of CCa as an effective alternative to chlorine.
Gautam, D.M., Tripathi, K.M., Mouylin, C., Buntong, B., Rahman, M.A., Bari, M.L., Acedo, A.L., Easdown, W., Hughes, J.A. and Keatinge, J.D.H. (2017). Effectiveness of non-chlorine sanitizers in enhancing quality and shelf life of tomato in Bangladesh, Cambodia and Nepal. Acta Hortic. 1179, 149-156
DOI: 10.17660/ActaHortic.2017.1179.23
Solanum lycopersicum, calcinated calcium, storage, shelf life

Acta Horticulturae