Publications by authors named "Alline A L Tribst"

This work explored the impact of ultrasound (US) on the activity, stability, and macrostructural conformation of cyclodextrin glycosyltransferase (CGTase) and how these changes could maximize the production of β-cyclodextrins (β-CDs). The results showed that ultrasonic pretreatment (20 kHz and 38 W/L) at pH 6.0 promoted increased enzymatic activity.

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This work investigated the fermentation kinetics and characteristics of goat yogurt supplemented with bovine whey protein isolate (WPI) (0%, 2.5% and 5.0%) subjected to high shear dispersion (HSD) assisted by ultrasound (US).

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Unlabelled: Goat (GCW) and sheep cheese whey (SCW) are cheese by-products that can be fermented to develop a new product. However, the limited nutrient availability for lactic acid bacteria (LAB) growth and the low stability of whey are challenges. This work evaluated the addition of protease and/or ultrasound-assisted fermentation as tools to improve GCW and SCW fermentation and the final quality of the products.

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This study evaluated the ability of ultrasound (US) bath to improve the hydrolysis of goat milk casein (GMC) by three commercial proteases (Alcalase, Brauzyn and Flavourzyme) using assisted reactions at 60 °C for up to 300 min. Process performance was evaluated based on the rate reaction, final hydrolysis degree, solubility, and antioxidant activity of the hydrolysates. For all enzymes, the US-assisted reaction increased the rate of GMC hydrolysis (up to 120%), the hydrolysis degree (23-48%), and the small peptides formed, i.

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This study evaluated the use of ultrasound (US), high-shear dispersion (HSD), stirring (ST), and low or high pressure homogenization (LPH or HPH) technologies to modify the goat milk cream (GMC) structure, focusing on improving the enzymatic hydrolysis of its lipids. The GMC structure was evaluated, as well as its creaming and emulsion stability index (ESI). The processed GMC was hydrolyzed by lipase at 50 °C for 300 min, and the fatty acids concentration (FAC) was evaluated over the reaction.

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The growing demand for plastics, for packaging and consumption, is a current environmental issue. Although there are many scientific developments concerning material science, knowledge about the public's perception is low, which can delay society's efforts to face this challenge. This study aimed to understand if Brazilians who practice different sustainable actions perceive differently biodegradable, recycled, and common plastics and have different purchase intentions for each specific type of packaging.

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This study aimed to identify individual, household and sociodemographic factors associated with changes in food consumption that lead to changes in the diet quality, in the context of the COVID-19 pandemic concerning Brazilian adults. Improvements or worsening in diet quality (IDQ or WDQ) were verified using an exploratory online survey which investigated whether participants (n = 4780) increased or decreased their consumption of food subgroups that mark positive or negative food patterns. Respondents also agreed or disagreed with their beliefs about food safety, cooking skills, family support, home characterization, feelings and behaviors.

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High-pressure homogenization (HPH) is an emerging process during which a fluid product is pumped by pressure intensifiers, forcing it to flow through a narrow gap, usually measured in the order of micrometers. Gums are polysaccharides from vegetal, animal or microbial origin and are widely employed in food and chemical industries as thickeners, stabilizers, gelling agents and emulsifiers. The choice of a specific gum depends on its application and purpose because each form of gum has particular values with respect to viscosity, intrinsic viscosity, stability, and emulsifying and gelling properties, with these parameters being determined by its structure.

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High pressure processing (HPP) is able to promote changes in enzymes structure. This study evaluated the effect of HP on the structural changes in milk-clotting enzymes processed under activation conditions for recombinant camel chymosin (212MPa/5min/10°C), calf rennet (280MPa/20min/25°C), bovine rennet (222MPa/5min/23°C), and porcine pepsin (50MPa/5min/20°C) and under inactivation conditions for all enzymes (600MPa/10min/25°C) including the protease from Rhizomucor miehei. In general, it was found that the HPP at activation conditions was able to increase the intrinsic fluorescence of samples with high pepsin concentration (porcine pepsin and bovine rennet), increase significantly the surface hydrophobicity and induce changes in secondary structure of all enzymes.

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This study investigated the effect of high pressure homogenization (HPH) (up to 190 MPa) on porcine pepsin (proteolytic and milk-clotting activities), and the consequences of using the processed enzyme in milk coagulation and gel formation (rheological profile, proteolysis, syneresis, and microstructure). Although the proteolytic activity (PA) was not altered immediately after the HPH process, it reduced during enzyme storage, with a 5% decrease after 60 days of storage for samples obtained with the enzyme processed at 50, 100 and 150 MPa. HPH increased the milk-clotting activity (MCA) of the enzyme processed at 150 MPa, being 15% higher than the MCA of non-processed samples after 60 days of storage.

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High pressure homogenization (HPH) is a non-thermal method, which has been employed to change the activity and stability of biotechnologically relevant enzymes. This work investigated how HPH affects the structural and functional characteristics of a glucose oxidase (GO) from Aspergillus niger. The enzyme was homogenized at 75 and 150 MPa and the effects were evaluated with respect to the enzyme activity, stability, kinetic parameters and molecular structure.

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High pressure homogenization (HPH) has been proposed as a promising method for changing the activity and stability of enzymes. Therefore, this research studied the activity of β-galactosidase before and after HPH. The enzyme solution at pH values of 6.

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Unlabelled: This work aimed to evaluate the effect of high-pressure homogenization (HPH) with heat shock on Aspergillus niger, vitamin C, and color of mango nectar. The nectar was processed at 200 MPa followed by heat shock, which was optimized by response surface methodology by using mango nectar ratio (45 to 70), heat time (10 to 20), and temperature (60 to 85 °C) as variables. The color of mango nectar and vitamin C retention were evaluated at the optimized treatments, that is, 200 MPa + 61.

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This research evaluated the inactivation of a heat-resistant Aspergillus niger conidia in mango nectar by high-pressure homogenization (HPH) combined with heat shock. A. niger were inoculated in mango nectar (10(6) conidia mL(-1)) and subjected to HPH (300 to 100 MPa) and heat shock (80 degrees C for 5 to 20 min) before or after HPH.

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In this review paper, several aspects of fruit juice microbiology, from past to future perspectives, are considered. An overview of the most relevant outbreaks involving foodborne pathogens and spoilage microorganisms associated with fruit juices is provided. One of the sections provides data on the sources of fruit juice contamination, followed by perspectives on preservation methods.

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