Effect of preservative agents on the respiration rate of minimally processed potato (Solanum tuberosum cv. Monalisa).

The shelf life of minimally processed potatoes (MPP) is limited by enzyme-catalyzed browning reactions, with the increase in respiration being another factor that affects quality retention of this product. Sulfites are commonly used as effective preservative agents in minimally processing potatoes, but ascorbic acid and citric acid are considered natural sulfite substitutes and more accepted by consumers. The aim of this study was to study the effect of combinations of the preservative agents cited above (sodium metabisulfite 0.1% and 0.5%; citric acid 0.1% and 0.5%; ascorbic acid 0.5%) on the respiration rate of MPP (cv. Monalisa) processed at both ambient and refrigerated temperatures. The results have revealed that there is a significant effect of dipping treatment and temperature on respiration rate of MPP. Sodium metabisulfite (SM) reduces respiratory activity up to 0.8 mL/kg/h. The addition of either citric or ascorbic acid enhanced the effect of SM on the reduction of the respiration rate of MPP. The strongest effect (up to 3.3 mL/kg/h) was observed when a combination of all 3 agents at the higher concentrations was employed at a temperature of 18 degrees C.