Effects of freeze-dried pulp of Eugenia uniflora L. and Opuntia ficus-indica fruits on quality attributes of beef patties enriched with n-3 fatty acids.

The objective of this work was to evaluate the effect of freeze-dried pulps of Eugenia uniflora L. and Opuntia ficus-indica fruits on oxidative stability of n-3-enriched beef patties. Besides, the effect of freeze-dried pulps on cooking yield, color, texture parameters and sensory acceptance of patties was also evaluated. Eugenia uniflora L. (orange-skinned variety) and Opuntia ficus-indica (orange-skinned and red-skinned varieties) fruits were collected, their pulp was lyophilized and incorporated, as a natural source of antioxidant, in beef patties enriched with canola oil as a source of polyunsaturated fatty acids. Oxidation stability of samples was monitored by measuring thiobarbituric acid-reactive substances during refrigerated storage. Results show that all freeze-dried pulps limited lipid oxidation to an acceptable level during 15 days refrigerated storage, having Opuntia ficus-indica (red-skinned variety) the highest inhibitory activity. Besides, the addition of freeze-dried pulps increased the cooking yield and decreased the hardness of beef patties. Respect to sensorial parameters, patties elaborated with no added freeze-dried fruit pulp and patties elaborated with freeze-dried pulp of Opuntia ficus-indica (red-skinned variety) presented the highest overall acceptance of consumers, remaining as a future task to improve the color and taste of patties elaborated with freeze-dried pulps of Eugenia uniflora L. and Opuntia ficus-indica (orange-skinned variety). This research reveals the effectiveness of studied fruits to reduce lipid oxidation in beef patties. In addition, preliminary information about which sensorial parameters of these products should be improved in futures incorporation of pulps in the manufacture of healthy meat products.

Development of gluten-free fish (Pseudoplatystoma corruscans) patties by response surface methodology.

The goal of this study was to develop a fish-based product suitable for people with celiac disease. Water and gluten-free flours (rice, corn, amaranth or quinoa) were added to improve cooking yield, texture parameters and as an aid in improving quality attributes such as taste and juiciness. Cooking yields of patties containing gluten-free flours were higher than control and maximum values ranged between 91 and 93%. Hardness was higher in patties made with amaranth or quinoa flour, whereas cohesiveness and springiness were higher in patties made with corn and rice flour, respectively. Response surface methodology was used to optimize patties formulations. Optimized formulations were prepared and evaluated showing a good agreement between predicted and experimental responses. Also, nutritional value and consumer acceptance of optimized formulations were analysed. Flours addition affected proximate composition increasing carbohydrates, total fat and mineral content compared to control. Sensory evaluation showed that no differences were found in the aroma of products. Addition of rice flour increased juiciness and tenderness whereas taste, overall acceptance and buying intention were higher in control patty, followed by patties made with corn flour. The present investigation shows good possibilities for further product development, including the scale up at an industrial level.