Abstract： Daqu distiller＇s grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The singl...Abstract： Daqu distiller＇s grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1：1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller＇s grains is possible. The research provides a new idea for the reuse of Daqu distiller＇s grains and also provides a new way for the development of microbial oils.展开更多
The objectives of the study were： a） to determine the optimal concentration of the extract that should be incorporated in meat products to maintain the lipid oxidative stability, and b） to verify if the extract exe...The objectives of the study were： a） to determine the optimal concentration of the extract that should be incorporated in meat products to maintain the lipid oxidative stability, and b） to verify if the extract exerted antioxidant activity even when these products were enriched with soybean oil （with fatty acids omega 3）. To carry out these aims, in the first instance the additive was incorporated into meat patties （elaborated with 80% beef and 20% fat plus 2% salt over total mass） at 0, 0.5, 1, 5 and 10 g/kg, respectively. The lipid oxidation was evaluated by measurement of peroxide value during 15 days at 8 ℃ and the results were expressed as reduction percentage of peroxidation （RP）. RP obtained were 55, 49, 73 and 59 respectively. As 5 g/kg was the optimum concentration of antioxidant, this was chosen to add to meat products enriched with soybean oil. In this case the RP obtained was 78%, indicating that the extract decreased lipid oxidation effectively.展开更多
Full use of residues from industrial processes is a fundamental necessity of contemporary society, since it avoids impacts to the environment by using residues as inputs for other products of high economic and social ...Full use of residues from industrial processes is a fundamental necessity of contemporary society, since it avoids impacts to the environment by using residues as inputs for other products of high economic and social importance. In this study, lipase production of the crude enzymatic extracts obtained by Aspergillus niger using cassava peel as substrate and sunflower oil as an inductor was investigated. The optimized cultivation temperature and concentration of inductor were determined using the response surface methodology. The two variables studied exercised influence in the production of lipase in the 95% level of confidence. The response surface obtained indicated that the conditions that maximize lipase activity production were 30.5 ~C and initial concentration of sunflower oil was 2.5% （w/w）. Through this analysis, it is evident that extremes in temperature and concentration of inductor tend to decrease lipase production, since low temperatures decrease metabolism and high temperatures may inactivate the lipase. Optimum lipase yield was 59.8 U/g of dry peel which was fermented for 60 h. Lipase production presents a peak of 61.3 U/g, at 72 h of fermentation. However, this value is statistically equal （p 〉 0.05） of the value of lipase activity obtained for 60 h and 84 h of fermentation.展开更多
基金Project(10A110) supported by Hunan Provincial Education Department of ChinaProject(2010JT4055) supported by Hunan Provincial Science & Technology Department of China
文摘Abstract： Daqu distiller＇s grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1：1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller＇s grains is possible. The research provides a new idea for the reuse of Daqu distiller＇s grains and also provides a new way for the development of microbial oils.
文摘The objectives of the study were： a） to determine the optimal concentration of the extract that should be incorporated in meat products to maintain the lipid oxidative stability, and b） to verify if the extract exerted antioxidant activity even when these products were enriched with soybean oil （with fatty acids omega 3）. To carry out these aims, in the first instance the additive was incorporated into meat patties （elaborated with 80% beef and 20% fat plus 2% salt over total mass） at 0, 0.5, 1, 5 and 10 g/kg, respectively. The lipid oxidation was evaluated by measurement of peroxide value during 15 days at 8 ℃ and the results were expressed as reduction percentage of peroxidation （RP）. RP obtained were 55, 49, 73 and 59 respectively. As 5 g/kg was the optimum concentration of antioxidant, this was chosen to add to meat products enriched with soybean oil. In this case the RP obtained was 78%, indicating that the extract decreased lipid oxidation effectively.
文摘Full use of residues from industrial processes is a fundamental necessity of contemporary society, since it avoids impacts to the environment by using residues as inputs for other products of high economic and social importance. In this study, lipase production of the crude enzymatic extracts obtained by Aspergillus niger using cassava peel as substrate and sunflower oil as an inductor was investigated. The optimized cultivation temperature and concentration of inductor were determined using the response surface methodology. The two variables studied exercised influence in the production of lipase in the 95% level of confidence. The response surface obtained indicated that the conditions that maximize lipase activity production were 30.5 ~C and initial concentration of sunflower oil was 2.5% （w/w）. Through this analysis, it is evident that extremes in temperature and concentration of inductor tend to decrease lipase production, since low temperatures decrease metabolism and high temperatures may inactivate the lipase. Optimum lipase yield was 59.8 U/g of dry peel which was fermented for 60 h. Lipase production presents a peak of 61.3 U/g, at 72 h of fermentation. However, this value is statistically equal （p 〉 0.05） of the value of lipase activity obtained for 60 h and 84 h of fermentation.
