Forecasting the Degradation of Vitamin C Concentration in Commonly Consumed Vegetable Cabbage (Brassica oleracea) dipped in Different Pre-treatment Solutions

Vitamin C is considered an essential vitamin that is commonly found in most fruits and vegetables. It is susceptible to easy degradation, especially during pre-treatment and storage. This study aimed at forecasting the degradation of vitamin C in commonly consumed vegetable (cabbage) dipped in different pre-treatment solutions at different time intervals. The samples after dipping at different time intervals were prepared for analysis. Evaluation of the ascorbic acid content of the vegetable was determined using High-Performance Liquid Chromatography (HPLC). This consists of an isocratic elution procedure with ultraviolet-visible detection at 245 nm. The half-lives and rate constants were calculated using the integrated law method. Forecasts were determined using time series analysis. Degradation of vitamin C in this study followed a first-order kinetic model, and the average coefficient of determination (R2-value) was greater than 0.9413. The rate constants of vitamin C degradation for the vegetable dipped in different pretreatment solutions (sodium chloride, sodium benzoate, sodium metabisulfite and vinegar) at different time intervals were 0.0804, 0.1049, 0.0706 and 0.0553 minutes-1; half-lives were 8.2322, 7.3896, 10.9675, and 12.1086 minutes, respectively. The vegetable dipped in different pretreatments for 90 minutes exhibited ln(C) forecast of -2.2057, -4.6307, -1.1746, and 0.0789, respectively. The coefficient of correlation for sodium chloride, sodium benzoate, sodium metabisulfite, and vinegar are 0.084, 0.093, 0.063 and 0.059 respectively. The kinetic models were formulated using predicted initial contents, processing time, and measured contents. The vegetable dipped in vinegar pretreatment solution using ln(C) =ln(C0) - 0.0553t gave the best model. From the results, the most appropriate pretreatment solution for enhancing the shelf life of cabbage is synthetic vinegar (prepared from acetic acid) because it has a lower rate constant, lower coefficient of correlation, and the longest half-life.