ABSTRACT
The aim of this paper was to study, step by step, the effect of ingredients and storage conditions on several properties of both the maize-based dough and the final product, during the new polenta-based snack food developing. Two different maize flours were characterized through water activity determination, particle size analysis, scanning electronic microscopy; then, dough made with different ratio of these were evaluated for mechanical properties and microstructure. According to the preliminary physicochemical characterization of both flour and dough, the final formulation was chosen for the polenta-based snacks. Thus, mechanical and sensory analyses, as well as microstructure determination, were performed on the final product. Results showed that the two maize flours presented different particle size distribution and gelatinization enthalpy, and affected the mechanical properties of intermediate products. The storage conditions dramatically affected the characteristics of the final products. Sensory results demonstrated that breading improves the crispness of external part but keeping creamy the product inside. The chosen approach was useful for understanding that flour particle size and storage are the critical factors that should be considered for this type of snack. The best formulation was made by mixing coarse and fine maize flours and by adding a batter.
ABSTRACT
The shelf life of fresh Italian pork sausages packed in modified atmosphere was studied. Samples were packed using different levels of oxygen (high and low) with different levels of carbon dioxide (high-low) in the atmospheres headspace and were stored at 4 °C for 9 days. Microbial, physiochemical and sensory parameters were analyzed during storage. A consumer test was performed to determine the critical acceptability levels. Sensory data were mathematically modelled to estimate product shelf life. A first-order kinetic model and a Weibull-type model aptly described, respectively, the changes in fresh pork sausage odor and color over storage time. These models may be used to predict the sensory shelf life of fresh pork sausage. Results showed that 20% O(2) and 70% CO(2) extend fresh pork sausage shelf life to 9 days at 4 °C. The microbial quality of the samples at the critical sensory level of acceptability was within the range of microbial acceptability.
