RESUMO
Valorisation of food processing by-products is a welcome and developing area. The mango processing industry produces 40% to 60% of the fruit as solid waste, in which components of industrial interest, such as pectin, are lost. This study reports on energy-efficient high-intensity ultrasound-assisted extraction (HIUAE) to extract pectin from mango peels. The analysis considered the ripening stage of the fruit (0, 2, and 4), HIUAE frequency (37 kHz and 80 kHz), and extraction time (20 min, 25 min, and 30 min). Extractions of pectin from mango peels with HIUAE have been fairly studied. However, this work differs from those studies in including mango maturity grade as a factor. Pectin extraction yields ranged from 13% to 30%, with no influence (p > 0.05) of time, and the highest yields were obtained at the lowest maturity stage (0) and lowest frequency (37 kHz). This latest condition (37 kHz) also yielded pectin with the highest gel strength, purity, and quality. This work demonstrated that the mango maturity stage influenced pectin extraction yield. Ultrasound-assisted extraction of pectin from mango peels could be an efficient approach toward waste valorisation and extraction of pectin with high yield and good quality attributes for the food industry.
RESUMO
Wheat is one of the most widely used cereals in the world. However, studies consider wheat flour doughs to be of low nutritional quality, as there is now greater public awareness of celiac disease and gluten intolerance. Therefore, consumers are demanding healthier and more varied food products. Consequently, wheat flour is being replaced fully or partially by flours from other sources with higher quality. Hence, the main objective of this work was to report the effect of blending wheat flour with ackee aril flour, until the total replacement of wheat flour, on pasting and dough rheological properties. Five different levels of blending were analyzed: wheat to ackee aril flour mass ratios of 100 : 0, 75 : 25, 50 : 50, 25 : 75, and 0 : 100. Pasting properties (pasting temperature, peak viscosity, ease of cooking, swelling power, final viscosity at 50 °C, and thixotropy) were analyzed; and steady-state shear measurements were used to obtain consistency coefficients (K) and flow behavior indexes (n) after data was fitted to the Power Law and Herschel-Bulkley models. The gradual addition of the ackee aril flour fraction produced an increase in ash, fat, protein, and fiber content; while water and carbohydrate content showed the opposite behavior in the obtained composite flour. Consequently, the partial or full replacement of wheat flour changed the rheological properties of the produced doughs, as well as the quality of the final product. These changes were mostly related to the protein and carbohydrate content of the ackee aril flour fraction. In general, doughs showed a pseudoplastic behavior with thixotropy whose viscosity decreased as the addition of ackee aril flour was increased. Pasting properties of blends involving 25 %-75 % ackee aril flour demonstrate the feasibility of including these flours in products subjected to high processing temperatures such as canned products or even to produce chips and pasta.
RESUMO
Textural attributes are a manifestation of the rheological properties and physical structure of foods, cheeses among these. In order to describe these physical properties, the objective of this work was to analyse the effect of deformation history on the stress relaxation behaviour of Colombian Caribbean coastal cheese made from goat milk with 3.75% (F1), 4.00% (F2) and 4.25% (F3) fat content, through prediction made by a four-term Prony series based on Chen's model. For this, stress relaxation data and stress relaxation spectra were analysed. Moreover, textural attributes by texture profile analysis were measured. Physicochemical results were similar to those published by other authors, and all samples meet national and international standards. Results from this work showed that Chen's model could be successfully used to describe the effect of deformation history on the stress relaxation behaviour of Colombian Caribbean coastal cheese made from goat milk. F1 had the highest elastic response, with the most significant residual modules ( P0) and relaxation times (τ1, τ2 and τ3). On the other hand, residual modules and relaxation times (τ1, τ2 and τ3) for cheeses F2 and F3 did not present statistically significant differences (p > 0.05). Besides, by interpretation of the stress relaxation spectra, F1 presented the firmest structure (greatest distribution function and relaxation time) which was characterised by the highest elastic behaviour. Finally, according to texture profile analysis test, F1 had the highest hardness, cohesiveness and chewiness, whereas F2 and F3 did not present statistically significant differences (p > 0.05) between them.