Stability cellulases of Bacillus sp. SMIA-2 during storage under freezing and in the presence of additives

Enzymatic stability is undoubtedly one of the most important factors in biotechnology. In this sense, the stability of cellulases present in crude extracts of submerged cultures of Bacillus sp. SMIA-2 during freezing at 3 °C and in the presence of additives was studied. Cellulases were stable during storage for 154 days at 3 °C. The activity of avicellase and CMCase was maintained when crude extracts containing the enzymes were incubated in the presence of ethylene glycol (1M), glycerol (1%) and polyethylene glycol (0.01M) for 1 hour at room temperature

Tratamento térmico e químico para controle da atividade da poligalacturonase no albedo do maracujá

The objective of this work was to evaluate the use of thermal and chemical treatments with Ca2+, in order to control the activity of polygalacturonase and its effects on extraction yield and degree of pectin esterification from albedo of yellow passion fruit (Passiflora edulis) rind. Rinds of fruit with light‑green peel were washed, sanitized, grind, and left to stand in water for albedo suspension. Albedo was collected and subjected to a temperature of 90oC for 30, 60, and 120 min, or to calcium levels of 0.01 and 1% during 1 hour of stirring, at 400 rpm, at ambient temperature. Thermal treatment of the crude enzymatic extract obtained from the albedo at 65, 75, and 85oC was also performed. The thermal treatment of the albedo at 90oC did not inactivate polygalacturonase after 120 min. The inactivation of the enzyme extracted from the albedo occurred after incubation at 65, 75, and 85oC for 30, 20, and 10 min, respectively. The treatment with calcium ion solution at 1% promoted enzymatic inactivation and a decrease in the content of free carboxylic acids (FCA) of pectin. The treatment of passion fruit albedo with calcium Ca2+ solution at 1% for 1 hour inhibits the polygalacturonase activity and decreases the content of FCA.O objetivo deste trabalho foi avaliar tratamentos térmicos e químicos com Ca2+, no controle da atividade da poligalacturonase e de seus efeitos no rendimento de extração e no grau de esterificação da pectina do albedo da casca de maracujá‑amarelo (Passiflora edulis). Utilizaram-se cascas de frutos com coloração verde‑clara, as quais foram lavadas, sanitizadas, trituradas e deixadas em repouso em água, para suspensão do albedo. O albedo foi recolhido e submetido à temperatura de 90oC a 30, 60 e 120 min, ou a concentrações de cálcio de 0,01 e 1% durante 1 hora de agitação de 400 rpm, em temperatura ambiente. Realizou-se, também, o tratamento térmico do extrato enzimático bruto obtido do albedo a 65, 75 e 85°C. O tratamento térmico do albedo a 90°C não inativou a poligalacturonase após 120 min. A inativação da enzima extraída do albedo ocorreu após incubação a 65, 75 e 85°C por 30, 20 e 10 min, respectivamente. O tratamento com íons de cálcio a 1% promoveu o bloqueio enzimático e a redução no conteúdo de ácidos urônicos livres (AUL) da pectina. O tratamento do albedo de maracujá com solução de 1% de Ca2+ por 1 hora inibe a atividade da poligalacturonase e reduz o conteúdo de AUL

Reducing fat and sodium content in pork sausage

This work aimed to prepare pork sausage using xanthan gum and light salt (NaCl/KCl) to replace the fat and common salt (NaCl), respectively, and to assess the impact of the changes in the chemical and sensory characteristics of the product. The consumers evaluated sensory acceptance with respect to flavor, odor, texture and appearance (mixed 9-point structured hedonic scale). The use of xanthan gum resulted in a decrease of 27.27% in fat content, 19.54% in the energy value and an increase in the percentage of moisture, thus giving a higher industrial yield. With the use of light salt, there was a reduction of 71.77% in sodium and an increase of 124.73% in potassium content. Formulation 1 scored the highest means for acceptance of appearance. On the other hand, formulation 2 scored the highest means for acceptance for the other attributes.Keywords: Meat products, light salt, sensory acceptance.African Journal of Biotechnology Vol. 12(24), pp. 3847-385