Immobilization of alpha acetolactate decarboxylase in hybrid gelatin/alginate support for application to reduce diacetyl off-flavor in beer

Beer production is the largest among alcoholic beverages. Its production process is complex and demands several steps. Lager beers commonly present an off-flavor of butter that is due to the presence of diacetyl, and to avoid such a problem, a long period of maturation (3–5 weeks) is required. Another way is the application of (α-acetolactate decarboxylase) ALDC to accelerate the process. The objectives of the present work were to develop a low-cost support using gelatin, a residue from capsules from the nutraceutical industry, to immobilize the ALDC enzyme. For this, the yield, efficiency and activity recovered, and the stability of free and immobilized enzymes at different temperatures and pH were evaluated. To evaluate the capacity of immobilized enzymes when applied directly to beer and their operational stability, three concentrations of glutaraldehyde (1%, 2.5% and 5%) were tested in distilled water as a cross-linking agent. The best results obtained were 95.6%, 27.0% and 23.6%, respectively, for yield, efficiency and activity recovery. Immobilization provided a high activity over a wide pH range. The immobilized enzyme showed greater stability at temperatures of 50 and 60 ◦C. The immobilized derivative showed adequate reuse capacity, and its dehydrated form had excellent activity after long periods of storage

Utilização de um resíduo industrial fibroso de soja para a produção de celulases e xilanases em cultivo semi-sólido

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Nutritional evaluation of Butia (Butia yatai) processed

No Rio Grande do Sul, destaca-se a relevância socioambiental de diferentes espécies de butiá (butiá yatai). Este trabalho teve como objetivo avaliar como o processo de despolpa de butiá interfere, ao longo de três meses de armazenamento, na composição do alimento, particularmente no valor calórico, no teor de fibras e na estabilidade do ácido ascórbico. Os frutos de butiá foram coletados e analisados entre os meses de março e junho de 2017, analisando-se parâmetros físico-químicos e centesimais da fruta e da polpa de butiá. Do ponto de vista físico-químico, a polpa, quando comparada à fruta, apresenta maior teor de umidade, de açúcares dissolvidos e teor de ácido cítrico. A polpa apresentou aumento de 24,5% na quantidade energética total, porém, quando se trata das fibras alimentares totais, houve redução de 47,9%. O teor de ácido ascórbico diminuiu 44,6% durante o período estudado. Tanto a fruta como a polpa apresentaram alto teor de fibras alimentares. Portanto, foi possível identificar que o processo de beneficiamento do butiá acarreta em mudanças nas características da fruta para a polpa, mas ambos os alimentos podem ser considerados nutritivos para compor a base da alimentação regional.In the state of Rio Grande do Sul, Brazil, it is important to highlight the socioenvironmental relevance of different butia species. The objective of this work was to evaluate how butia (Butia yatai) pulping process interferes, within three months of storage, in the food composition — particularly caloric value, fiber content and the stability of ascorbic acid. Butia fruits were collected and analyzed between March and June 2017, analyzing physico-chemical properties and centesimal composition of butia fruit and pulp. Regarding the physico-chemical characteristics, the pulp, when compared to the fruit, presents a higher content of moisture, dissolved sugars and citric acid. Also, the pulp showed a 24.5 % increase in the total energy content. However, when it comes to the total dietary fiber, there was a 47.9 % reduction. The ascorbic acid content decreased 44.6 % during the studied period. Both fruit and pulp presented a high fiber content. Therefore, it was possible to identify that the fruit processing involves changes on the pulp characteristics, but both, the in nature fruit and processed, can be considered nutritious and of good assistance in the regional diet

Development of a biocomposite based on alginate/gelatin crosslinked with genipin for β-galactosidase immobilization: Performance and characteristics

In this work, we studied the development of a biocomposite formulated with alginate and gelatin, crosslinked with genipin for application as support for β-galactosidase immobilization. Also, the biocomposites with the immobilized enzyme were characterized by thermal analyses and SAXS (size, density, and interconnectivity of alginate rods) for a detailed analysis of the microstructure, as well as the thermal and operational stabilities of the enzyme. The structural modifications of the biocomposite determined by SAXS demonstrate that the addition of both genipin and enzyme produced a significant reduction in size and density of the Ca(II)-alginate rods. Immobilized β-galactosidase could be stored for 175 days under refrigeration maintaining 80% of its initial activity. Moreover, 90% of its relative activity was kept after 11 reuses in a batch process of lactose hydrolysis. Thus, the biocomposite proved to be effective as support for enzyme immobilization.Fil: Hackenhaar, Camila Regina. Universidade Federal do Rio Grande do Sul; BrasilFil: Flores Rosa, Carolina. Universidade Federal do Rio Grande do Sul; BrasilFil: Esparza Flores, Elí Emanuel. Universidade Federal do Rio Grande do Sul; BrasilFil: Santagapita, Patricio Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Poletto Klein, Manuela. Universidade Federal de Ciencias Da Saúde de Porto Alegre; BrasilFil: Hertz, Plinho Francisco. Universidade Federal do Rio Grande do Sul; Brasi

Produção de goma xantana em cultivo semi-sólido : determinação das condições ótimas de extração

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Aproveitamento de um resíduo fibroso de soja para a produção de goma xantana em cultivo semi-sólido

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High performance biocatalyst based on β-D-galactosidase immobilized on mesoporous silica/titania/chitosan material

A new support for the immobilization of β-D-galactosidase from Kluyveromyces lactis was developed, consisting of mesoporous silica/titania with a chitosan coating. This support presents a high available surface area and adequate pore size for optimizing the immobilization efficiency of the enzyme and, furthermore, maintaining its activity. The obtained supported biocatalyst was applied in enzyme hydrolytic activity tests with o-NPG, showing high activity 1223 Ug 1, excellent efficiency (74%), and activity recovery (54%). Tests of lactose hydrolysis in a continuous flow reactor showed that during 14 days operation, the biocatalyst maintained full enzymatic activity. In a batch system, after 15 cycles, it retained approximately 90% of its initial catalytic activity and attained full conversion of the lactose 100% (±12%). Additionally, with the use of the mesoporous silica/titania support, the biocatalyst presented no deformation and fragmentation, in both systems, demonstrating high operational stability and appropriate properties for applications in food manufacturing

Estudo da inibição de atividade proteolítica e preservação da atividade de xilanases em extratos produzidos por bactérias isoladas de ambientes amazônicos em condições de cultivo semi-sólido

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Produção biotecnologica de lipases

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Perfil de atividade xilanolítica de Bacillus coagulans isolados de ambientes amazônicos

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