An existing small-scale single-powered baking oven was modified and optimize into a dual-powered oven. The oven was redesigned to accommodate the initially designed firewood heat source and the newly introduced gas he...An existing small-scale single-powered baking oven was modified and optimize into a dual-powered oven. The oven was redesigned to accommodate the initially designed firewood heat source and the newly introduced gas heat source. Four heat exchangers (thermal pipes) were introduced to the baking chamber for effective heat and mass transfer during baking of bread dough. The thermal pipes were made of 2 mm thick hollow galvanized steel pipe of 23 mm diameter and 660 mm length. The performance of the oven was evaluated using the standard performance index, which includes baking capacity, baking efficiency and weight loss of the baked bread. The baked bread’s physical properties were determined and analyzed using Duncan multiple range ANOVA test at significant level of <em>p</em> < 0.05. These properties were optimized to determine the generate regression models using 3D model plot. The baking capacity, baking efficiency, weight loss and optimum baking temperature were: 101.9 kg/h, 46.44% (wood-fired);70.34% (gas-fired), 13.5 g (wood-fired);and 25.5 g (gas-fired), 150<span style="white-space:nowrap;">˚</span>C, respectively. The physical properties of baked bread, wood-fired were found to correspond with that of gas-fired oven. The modified oven can be used for the baking of dough at domestic, small and medium scale bakery.展开更多
A Lactobacillus sp.was screened from various cereal sourdoughs and was designated as Lactobacillus plantarum YXY418 based on the 16S rRNA gene analysis.A putative Lactobacillus plantarum maltogenic amylase,LpMA,was di...A Lactobacillus sp.was screened from various cereal sourdoughs and was designated as Lactobacillus plantarum YXY418 based on the 16S rRNA gene analysis.A putative Lactobacillus plantarum maltogenic amylase,LpMA,was discovered based on computer-aided analysis.Then,its encoding gene(lpma)was expressed in E.coli BL21(DE3).The expressed recombinant LpMA(reLpMA)was efficiently purified to 12.2-fold using the one-step nickel-nitrilotriacetic acid(Ni–NTA)affinity chromatography.The final recovery yield and specific activity of the purified reLpMA were 61%and 36.4 U/mg towards soluble starch,respectively.The purified reLpMA exhibited optimal amylolytic activity towards soluble starch at 45℃ and pH 6.0,with a good pH stability ranging from pH 5.0 to 8.0.Besides,the reLpMA also hydrolyzed soluble starch,β-CD and pullulan to maltose with specific activity of 96.4 SU/mL,78.2 CU/mL and 2.0 PU/mL,respectively.The reLpMA hydrolytic activity was increased in the presence of metal ions especiallyCa^(2+)andZn^(2+),which could be applied to different processing processes.Baking test indicated after 7-day storage,the reLpMA at a dosage of 2000 U/300 g could significantly reduce hardness and chewiness by 29.5%and 26.4%,respectively,compared with the control.Adding reLpMA improved bread quality,increased bread volume and decreased hardness during storage,thus extending its shelf life.展开更多
This study aimed to investigate the effect of incorporation of kiwifruit substrate fermented by 3 highβ-glucosidase producing lactic acid bacteria(LAB)of Lactobacillus harbinensis(M12,M24)and Pediococcus pentosaceus(...This study aimed to investigate the effect of incorporation of kiwifruit substrate fermented by 3 highβ-glucosidase producing lactic acid bacteria(LAB)of Lactobacillus harbinensis(M12,M24)and Pediococcus pentosaceus(J28)on physicochemical and rheo-fermentation properties during proofing of wheat dough.Quality,sensory evaluation,antioxidant content and activity,and flavor profiles of bread was evaluated.Results revealed that LAB strains adequately adapted(J28>M12>M24)and produced enzymes during substrate fermentation.In dough,incorporation of fermented substrate increased acidity,soluble dietary fiber,β-glucosidase andα-amylase activity and gas retention during proofing,in a strain dependent manner(J28>M12>M24).The subsequent breads exhibited higher specific volume and had softer crumbs.Furthermore,total flavonoid,total phenolic,antioxidant activity,flavor content and intensity increased in breads incorporated with fermented substrate.Overall sensory acceptance was in order,bread containing substrates fermented by J28(KFB-J28)>M12(KFB-M12)>M24(KFB-M24)>wheat bread(WB)>bread containing unfermented substrate(KFB).Changes observed were attributed to biotransformation byβ-glucosidase which increasingly degraded dietary fibers into soluble dietary fiber,increased acidity,released glycosylated aroma compounds and phenolic compounds in substrate.When incorporated in dough,fermented kiwifruit substrates stabilized gluten network,increased yeast metabolism and gas retention during proofing.Subsequently,KFB-J28,KFB-M12,and KFB-M24 had higher antioxidant content and activity,higher flavor content and intensity,better quality and were more accepted compared to WB and KFB.This suggested the potential role played byβ-glucosidases through LAB fermentation on functionally enriching and adding value to kiwifruit substrate as a novel functional ingredient in bakery industry.展开更多
文摘An existing small-scale single-powered baking oven was modified and optimize into a dual-powered oven. The oven was redesigned to accommodate the initially designed firewood heat source and the newly introduced gas heat source. Four heat exchangers (thermal pipes) were introduced to the baking chamber for effective heat and mass transfer during baking of bread dough. The thermal pipes were made of 2 mm thick hollow galvanized steel pipe of 23 mm diameter and 660 mm length. The performance of the oven was evaluated using the standard performance index, which includes baking capacity, baking efficiency and weight loss of the baked bread. The baked bread’s physical properties were determined and analyzed using Duncan multiple range ANOVA test at significant level of <em>p</em> < 0.05. These properties were optimized to determine the generate regression models using 3D model plot. The baking capacity, baking efficiency, weight loss and optimum baking temperature were: 101.9 kg/h, 46.44% (wood-fired);70.34% (gas-fired), 13.5 g (wood-fired);and 25.5 g (gas-fired), 150<span style="white-space:nowrap;">˚</span>C, respectively. The physical properties of baked bread, wood-fired were found to correspond with that of gas-fired oven. The modified oven can be used for the baking of dough at domestic, small and medium scale bakery.
基金supported by the National Natural Science Foundation of China(21676117)the Natural Science Foundation of Jiangsu Province for Youth of China(No.BK20180622).
文摘A Lactobacillus sp.was screened from various cereal sourdoughs and was designated as Lactobacillus plantarum YXY418 based on the 16S rRNA gene analysis.A putative Lactobacillus plantarum maltogenic amylase,LpMA,was discovered based on computer-aided analysis.Then,its encoding gene(lpma)was expressed in E.coli BL21(DE3).The expressed recombinant LpMA(reLpMA)was efficiently purified to 12.2-fold using the one-step nickel-nitrilotriacetic acid(Ni–NTA)affinity chromatography.The final recovery yield and specific activity of the purified reLpMA were 61%and 36.4 U/mg towards soluble starch,respectively.The purified reLpMA exhibited optimal amylolytic activity towards soluble starch at 45℃ and pH 6.0,with a good pH stability ranging from pH 5.0 to 8.0.Besides,the reLpMA also hydrolyzed soluble starch,β-CD and pullulan to maltose with specific activity of 96.4 SU/mL,78.2 CU/mL and 2.0 PU/mL,respectively.The reLpMA hydrolytic activity was increased in the presence of metal ions especiallyCa^(2+)andZn^(2+),which could be applied to different processing processes.Baking test indicated after 7-day storage,the reLpMA at a dosage of 2000 U/300 g could significantly reduce hardness and chewiness by 29.5%and 26.4%,respectively,compared with the control.Adding reLpMA improved bread quality,increased bread volume and decreased hardness during storage,thus extending its shelf life.
基金We are grateful for the financial supports of the research from Grants(31071595,20576046)from the National Natural Science Foundation of ChinaNational Key Special Project for the 13th National 5-Year Plan Program of China(2016YFD0400500)+2 种基金Shandong Taishan Leading Talents Expert Program of China(202025)Fujian“Hundreds of Talents Expert”Program of China(20172022)MagiBake International,Inc.(Wuxi,China).
文摘This study aimed to investigate the effect of incorporation of kiwifruit substrate fermented by 3 highβ-glucosidase producing lactic acid bacteria(LAB)of Lactobacillus harbinensis(M12,M24)and Pediococcus pentosaceus(J28)on physicochemical and rheo-fermentation properties during proofing of wheat dough.Quality,sensory evaluation,antioxidant content and activity,and flavor profiles of bread was evaluated.Results revealed that LAB strains adequately adapted(J28>M12>M24)and produced enzymes during substrate fermentation.In dough,incorporation of fermented substrate increased acidity,soluble dietary fiber,β-glucosidase andα-amylase activity and gas retention during proofing,in a strain dependent manner(J28>M12>M24).The subsequent breads exhibited higher specific volume and had softer crumbs.Furthermore,total flavonoid,total phenolic,antioxidant activity,flavor content and intensity increased in breads incorporated with fermented substrate.Overall sensory acceptance was in order,bread containing substrates fermented by J28(KFB-J28)>M12(KFB-M12)>M24(KFB-M24)>wheat bread(WB)>bread containing unfermented substrate(KFB).Changes observed were attributed to biotransformation byβ-glucosidase which increasingly degraded dietary fibers into soluble dietary fiber,increased acidity,released glycosylated aroma compounds and phenolic compounds in substrate.When incorporated in dough,fermented kiwifruit substrates stabilized gluten network,increased yeast metabolism and gas retention during proofing.Subsequently,KFB-J28,KFB-M12,and KFB-M24 had higher antioxidant content and activity,higher flavor content and intensity,better quality and were more accepted compared to WB and KFB.This suggested the potential role played byβ-glucosidases through LAB fermentation on functionally enriching and adding value to kiwifruit substrate as a novel functional ingredient in bakery industry.
