Effect of enzymatic hydrolyzed protein from pig bones on some biological and functional properties.

Pig bone residue is considered a potential source of hydrolysates from its protein with added value uses in the food industry. This work deals with the enzyme hydrolysis of pig bone protein. The conditions for extracting the protein hydrolysate were optimized and the equation obtained allowed samples with different degrees of hydrolysis (DH) to be extracted to study how the biological properties of in-vitro hydrolized protein affected digestibility, determination of the inhibitory activity of the angiotensin-converting enzyme and the antioxidant activity and its functional properties.

Polysaccharides from pineapple core as a canning by-product: Extraction optimization, chemical structure, antioxidant and functional properties.

Ultrasonic-assisted extraction (UAE) technique has been investigated to extract polysaccharides from pineapple core as a by-product using response surface methodology. A Box-Behnken design was employed to optimize the conditions for the maximum extraction yield of polysaccharides. The results demonstrated that the optimum extraction conditions were as follows: water/solid material ratio of 29.

Optimization of extraction and deamidation of edible protein from evening primrose (Oenothera biennis L.) oil processing by-products and its effect on structural and techno-functional properties.

The optimization of ultrasound-assisted alkaline extraction and enzymatic deamidation by protein-glutaminase (PG) on evening primrose seed cake (EPSC) protein and its effect on structure (amino acid composition, secondary structure and electrophoresis pattern) and techno-functional properties (water-holding and oil-binding capacities, solubility, emulsifying and foaming properties) of EPSC protein were evaluated. The optimum conditions of the both processes were measured using response surface methodology (RSM). The maximum yield (26.

Application of Ultrasound-Ultrafiltration-Assisted alkaline isoelectric precipitation (UUAAIP) technique for producing alfalfa protein isolate for human consumption: Optimization, comparison, physicochemical, and functional properties.

A new Ultrasound-Ultrafiltration-Assisted Alkaline Isoelectric Precipitation (UUAAIP) technique was employed for producing alfalfa protein isolate from alfalfa leaves. A five-factor-three-level Box-Behnken Design (BBD) was used to optimize the UUAAIP process for maximizing both extraction yield and protein content simultaneously. The optimum conditions were as follows: solvent/solid material ratio of 43.

Optimisation and kinetic study of the ultrasonic-assisted extraction of total saponins from alfalfa (Medicago sativa) and its bioaccessibility using the response surface methodology.

The ultrasonic-assisted extraction of total saponins from alfalfa leaves was optimised by the simultaneous maximization of the yield and bioaccessibility as a factor with increasingly great relevance in the biological activity by Response Surface Methodology. The kinetics of total saponins and bioaccessibility were investigated for the optimum ultrasound-assisted method compared to conventional method by the pseudo-first order model. The optimum extraction conditions were of solvent/raw material ratio of 11.

Ascorbic acid degradation in aqueous solution during UV-Vis irradiation.

This work studied the effect of multi-wavelength UV processing on the ascorbic acid content of aqueous solutions, at different pH values (3, 4, and 5). The source of radiation was a mid-pressure mercury lamp (460 W), emitting between 250 and 740 nm. The samples were treated for 60 min, at 25 °C and 45 °C, with the lamp on and with the lamp off.

Optimisation of steam blanching on enzymatic activity, color and protein degradation of alfalfa (Medicago sativa) to improve some quality characteristics of its edible protein.

The use of alfalfa protein in human food is limited by its low quality. Response Surface Methodology was employed to optimise the combined effects of different steam blanching conditions on the enzymatic activity, browning and protein degrading which cause undesirable characteristics. The optimum conditions were: steaming time 4.

Bleaching of sugar cane juice using a food-grade adsorber resin and explained by a kinetic model describing the variation in time of the content of adsorbate.

This work studies the adsorption of colored compounds in cane juice using a food-grade macroporous adsorber resin without functional groups. The adsorption equilibrium was studied through the adsorption isotherms at 30, 40, and 50 ℃. The absorbance at 420 nm was used to measure the concentration of colored compounds, which enables correlation of the residual concentration with the adsorbed concentration.

Kinetic and thermodynamic study of the photochemical degradation of patulin.

In a previous work, the UV photodegradation of patulin was concluded to follow a first-order kinetic and to be faster at acidic pH. In this case, the UV photodegradation of aqueous patulin solutions was studied at acidic pH values (3-6) similar to the values of apple juices where patulin has been found, obtaining that the first-order kinetic constant increased when the acidity of the reaction media was also increased (pH decreased). From the parameters obtained by fitting the experimental data to both the Arrhenius and Van't Hoff equations, the existence of kinetic and thermodynamic compensations was studied.

Kinetic and thermodynamic compensation. A current and practical review for foods.

Kinetic and thermodynamic compensations have been reported in many chemical, physical, biological and food processes. Kinetic compensation can be found for any process and when it takes place, it gives information about the reaction mechanism and whether the reaction is controlled by enthalpy or entropy. It consists of the linear relationship between the logarithm of the frequency factor (lnk) and the activation energy (E), both previously obtained from the Arrhenius equation for different values of an environmental variable (e.

Ascorbic acid stability in fruit juices during thermosonication.

Thermosonication is an emerging technology useful for inactivating microorganisms and enzymes in fruit juices. However, the effect of the ultrasound processing on the ascorbic acid content is not clear and the results reported in the literature are contradictory. In this work, the impact of sonication and thermosonication on the ascorbic acid content was first evaluated in model systems.

Mechanisms for improving mass transfer in food with ultrasound technology: Describing the phenomena in two model cases.

The aim of this work was to demonstrate how ultrasound mechanisms (direct and indirect effects) improve the mass transfer phenomena in food processing, and which part of the process they are more effective in. Two model cases were evaluated: the hydration of sorghum grain (with two water activities) and the influx of a pigment into melon cylinders. Different treatments enabled us to evaluate and discriminate both direct (inertial flow and "sponge effect") and indirect effects (micro channel formation), alternating pre-treatments and treatments using an ultrasonic bath (20 kHz of frequency and 28 W/L of volumetric power) and a traditional water-bath.

Peroxidase (POD) and polyphenol oxidase (PPO) photo-inactivation in a coconut water model solution using ultraviolet (UV).

The interest in coconut water as a beverage is increasing due, not only to its sensory properties, but also to its nutritional characteristics. Even so, several challenges limit its processing, the inactivation of the polyphenol oxidase (PPO) and peroxidase (POD) enzymes being the most important. Although the inactivation of these enzymes has been extensively studied in coconut water, both by conventional and emerging technologies, the technologies evaluated so far are either not effective in the inactivation of these enzymes and/or result in undesirable changes.

An autocatalytic kinetic model for describing microbial growth during fermentation.

The mathematical modelling of the behaviour of microbial growth is widely desired in order to control, predict and design food and bioproduct processing, stability and safety. This work develops and proposes a new semi-empirical mathematical model, based on an autocatalytic kinetic, to describe the microbial growth through its biomass concentration. The proposed model was successfully validated using 15 microbial growth patterns, covering the three most important types of microorganisms in food and biotechnological processing (bacteria, yeasts and moulds).

Chemical guide parameters for Spanish lemon (Citrus limon (L.) Burm.) juices.

To contribute for setting reference guideline for commercial juice extracted from the Spanish lemon varieties, chemical composition of 92 direct and 92 reconstituted samples were investigated. In direct lemon juice, titratable acidity was 52.4 g/L, being the citric acid the main component.

Albedo hydrolysis modelling and digestion with reused effluents in the enzymatic peeling process of grapefruits.

Background: Until now, the optimisation of enzymatic peeling of grapefruit in the reactor has been obtained as the result of the semi-qualitative effects of enzyme activity. This work is an attempt to obtain quantified data. The reuse of enzymes to reduce costs in this process is unprecedented in the literature and is the aim of the present work.

Toxic effect of melanoidins from glucose-asparagine on trypsin activity.

In this work the effect of the presence of the melanoidins from glucose-asparagine on the enzymatic activity of trypsin is studied. It was observed that an excess of N alpha-benzoyl-L-arginine ethyl ester (BAEE) has an inhibiting effect on this enzyme activity. The maximum reaction rate was obtained for a 0.

[Effect of high hydrostatic pressure on water imbibition, cooking times and microstructure of Phaseolus vulgaris].

The effect of high hydrostatic pressure (HHP) on water imbibition, cooking times, and microstructure of cotyledons and seed coats of black beans was evaluated. High pressure treatments at 275, 410, 550 or 690 MPa and 25 degrees C for 5 min increased the rate of water imbibition of black beans. The saturation degree of HHP treated black beans was reached 50% faster than the saturation degree of untreated black beans.