Vitamin C loss kinetics and shelf life study in fruit-based baby foods during post packaging storage

Simultaneous evolution of main components of L-ascorbic acid (AA) degradation route [AA, dehydro-L-ascorbic acid (DHA), and 2,3-diketogulonic acid (DKA)] were determined in three types of commercial fruit-based baby foods with different water or moisture content (MC) and stored over various periods of time (t) at different temperatures (T). The role of L-cysteine (Cys) on AA degradation was also studied. T, MC, and t were the main independent variables or factors affecting AA and DKG during post packaging storage. Similar pattern of AA degradation was observed in all products. Changes of AA during storage followed zero-order reaction kinetics. AA retention was higher (> 68 %) in those foods stored under refrigeration. Statistically significant relationship was estimated between time when maximum DKG was determined and T. Strong and moderately strong relationships were found between AA and Cys in 36 total trials at the 90 % or higher confidence level. Decreasing Cys promoted DKG formation and loss of biological activity and health benefits. Based on AA retention, a significant reduction of shelf life was determined for all products. Significance and implication of Cys supplementation of foods for infants and young children is discussed.