Physicochemical Properties of Commercial Gums and their Effects on Processing and Cooking Quality of Nontraditional Pasta
Abstract
Processing characteristics and quality of pasta made from durum flour and semolina and the physicochemical properties of commercial gums and their effects on processing and cooking quality of nontraditional pasta was investigated. An initial experiment was conducted using semolina and durum flour fortified with nontraditional ingredients (soy flour or oat flour, 10% w/w) and xanthan, guar or locust bean gums (2% w/w). A second set of experiments were conducted to determine the effect of commercial source of food gums on their effect on the processing and cooking quality of nontraditional pasta. Proper hydration of nontraditional ingredient blends was more easily achieved with durum flour than semolina. This was attributed to the smaller particle size of durum flour compared to semolina. Nontraditional ingredients tended to over hydrate semolina resulting in large aggregates that adhered to metal surfaces, all of which made mixing and pasta processing difficult. Initially, dough strength was greater with durum flour than with semolina, but semolina had better dough stability over time. Soy and oat flours reduced dough strength. Xanthan and guar gums increased dough stability, particularly with durum flour. Pasta made with durum flour generally had greater cooking loss and lower cooked firmness than pasta made from semolina. Soy and oat flours reduced cooked firmness and increased cooking loss. Guar and locust bean gums did not affect cooking quality of pasta. Xanthan gum increased cooked firmness of pasta. Samples of each gum were obtained from three different commercial vendors. For each food gum, samples varied in bulk density, molecular weight, viscosity in distilled water and the magnitude of effect on dough strength with commercial source. The effect of xanthan, guar and locust gums on hydration, dough strength, and cooking quality was not affected by commercial source. The magnitude of the increase in dough strength caused by xanthan and guar gums varied among their respective commercial sources.