Publications by authors named "Salvador Valle-Guadarrama"

Soursop ( L.) is a commercially important tropical fruit, whether fresh or processed as a pasteurized or frozen pulp used to prepare juice, drinks, nectar, ice cream, popsicles, and desserts. Besides preserving quality, another preoccupation in the processing of fruit pulps is product safety.

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Betalains of pitaya () fruit can be used as natural pigment, but they are susceptible to deterioration by temperature, pH, and presence of sugars. In this work, a refined extract (Er) of betalains was obtained through aqueous two-phase extraction, which reduced significantly sugar and mucilage contents. In order to favor stability, the encapsulation of the refined extract was evaluated, with native potato starch that was modified through phosphorylation or succinylation and reactive extrusion.

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Fruits with red and orange flesh of the columnar cactus pitaya (Stenocereus pruinosus) were studied to evaluate physical characteristics, total soluble solids, betalains and soluble phenols content, and antioxidant activity. Fruits had, in average, weight of 179.0 g, 9.

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A model that predicts temperature changes in a pilot plant thermophilic anaerobic digester was developed based on fundamental thermodynamic laws. The methodology utilized two simulation strategies. In the first, model equations were solved through a searching routine based on a minimal square optimization criterion, from which the overall heat transfer coefficient values, for both biodigester and heat exchanger, were determined.

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The effect of heating strategy on power consumption and performance of a pilot plant anaerobic digester treating chicken litter, under thermophilic conditions, has been studied. Heating strategy was evaluated using three different spans (0.2 degrees C, 0.

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