ABSTRACT

Keeping in view of the concern for human sensitivity to sulfites (FDA, 1987, 1996), the potential for regulatory actions banning sulfites on potatoes and the decrease in consumer acceptance of sulfite-treated products, research has been conducted on alternative anti-browning agents. Giannuzzi and Zaritzky (1993) analyzed the effect of citric acid and ascorbic acid (alone or in combination) compared to Na2S 0 2 on microbial growth in potato homogenate during storage at 4° C. Prepared potato homogenate was mixed with the preservatives prior to packaging in test tubes and wrapping in ethylene vinyl acetate (EVA)-Saran-EVA plastic film. During the study, the microbial flora consisted mostly of Enterobacteriaceae, Pseudomonas sp., Lactobacillus sp., psychrotrophic microorganisms, mold and yeasts. R hodotorula was the predominant yeast genera while Aspergillus, Aiternaria, Cladosporium and Penicillium were typical molds. Low concentrations (100 Mg.g1) of Na2S 0 2 had no inhibitory effect on microbial growth while citric acid (3 ,500 Mg.g1) and ascorbic acid (10,000 μg.gл) exhibited antimicrobial action. These authors concluded that although 100 Mg.g'1 Na2S 0 2 was not inhibitory, citric and ascorbic acids were good antimicrobial agents alone or in combination, in the potato homogenate system.