| Abstract: | The most common chemical preservatives used to inhibit both enzymatic browning and microbial growth in pre-peeled potatoes are sodium sulphite and bisulphite. Since 1987 the FDA has limited their use as food ingredients; consequently, during recent years the tendency to replace sulphites by GRAS chemical additives such as citric and ascorbic acids has become stronger. In the present work, surface colour variations, exudate production and microbial growth were analysed on pre-peeled potatoes treated with citric and ascorbic acids. These preservatives were applied individually and as mixtures; shelf-life was extended and microbiologically safe products were obtained. Mathematical models were solved to analyse the diffusion of these acids during immersion and storage periods in order to determine the concentration profiles within the product and to predict the surface concentration to which the microorganisms are exposed. |
