The synergistic effect of organoclay(OC)and zinc oxide(ZnO)nanoparticles on the crucial properties of poly(lactic acid)(PLA)nanocompositefilms was systematically investigated herein.After their incorporation into PLA v...The synergistic effect of organoclay(OC)and zinc oxide(ZnO)nanoparticles on the crucial properties of poly(lactic acid)(PLA)nanocompositefilms was systematically investigated herein.After their incorporation into PLA via the solvent casting technique,the water vapor barrier property of the PLA/OC/ZnOfilm improved by a maximum of 86%compared to the neat PLAfilm without the deterioration of Young’s modulus or the tensile strength.Moreover,thefilm’s self-antibacterial activity against foodborne pathogens,including gram-negative(Escherichia coli,E.coli)and gram-positive(Staphylococcus aureus,S.aureus)bacteria,was enhanced by a max-imum of approximately 98–99%compared to the neat PLAfilm.Furthermore,SEM images revealed the homo-geneous dispersion of both nano-fillers in the PLA matrix.However,the thermal stability of thefilm decreased slightly after the addition of the OC and ZnO.Thefilm exhibited notable light barrier properties in the UV-Vis range.Moreover,the incorporation of a suitable biodegradable plasticizer significantly decreased the Tg and notably enhanced theflexibility of the nanocompositefilm by increasing the elongation at break approxi-mately 1.5-fold compared to that of the neat PLAfilm.This contributes to its feasibility as an active food packa-ging material.展开更多
This study investigates the tenderizing effects of bromelain extract (BE) obtained from the top phase of an aqueous two-phase system comprising of 18% PEG 6000–17% MgSO4 in muscle foods. Uniform-sized chunks of beef,...This study investigates the tenderizing effects of bromelain extract (BE) obtained from the top phase of an aqueous two-phase system comprising of 18% PEG 6000–17% MgSO4 in muscle foods. Uniform-sized chunks of beef, chicken, and squid were marinated with different concentrations of BE (0, 3, 7%, and 20%, w/w) for 1 h at room temperature. The physico-chemical and quality characteristics of the marinated samples were determined. Decreases in pH and moisture content were observed in the samples BE treated, but the TCA-soluble peptides content significantly increased (p < 0.05). Water holding capacity and cooking yields were observed in all of the tested samples, especially when the concentration of BE increased. In addition, a reduction of meat firmness and toughness were also observed in all of the samples when compared to the control (p < 0.05). Electrophoretic patterns also revealed extensive proteolysis and a reduction in number and intensity of the protein bands in all of the treated samples. At the microstructural level, tissue fibers were broken, cell membranes were more strongly degraded, the connections between the sarcolemma and the myofibrils were disappeared, and the generation of numerous gaps could be clearly observed when 20% (w/w) BE was added. The results show that the bromelain extract derived from the two-phase extraction of a pineapple peel could be used as an effective meat tenderizer.展开更多
Tapioca is economical crop grown in Thailand and continues to be one of the major sources of starch.Nowadays,tapioca starch has been widely used in industrial applications,however the native form of starch has limited...Tapioca is economical crop grown in Thailand and continues to be one of the major sources of starch.Nowadays,tapioca starch has been widely used in industrial applications,however the native form of starch has limited the applications.Thus scientists try to modify the properties of starch for increasing the stability of the granules,pastes to low pH,heat,and shear during the food process.We modify the tapioca starch by plasma treatment under an argon atmosphere.The degree of modification is determined by following water content in the starch granules.The tablet samples of native starch are also prepared and compared with the plasma treated starch.Before plasma treatment,the starch tablets are stored under three different relative humilities(RH)including 11%,68%,and 78%RH,respectively.The samples are characterized using FTIR spectroscopy associated with the degree of cross-linking.The results show that the water molecules are engulfed into the starch structure in two ways,a tight bond and a weak absorption of water molecules which is represented at two wave number of 1630 cm^(-1) and 3272 cm^(-1),respectively.The degree of cross-linking can be identified from the relative intensity of these two peaks with the C–O–H peak at 993 cm^(-1).The results show that the degree of cross-linking increase in the plasma treated starch.The degree of cross-linking of the treated starch with high relative humidity is less than that of the treated starch with low relative humidity.展开更多
Many industrial processes may quickly proceed with biotechnological and enzymatic support.Functional and production facilitator properties of enzymes have provided variable advantages for industry.Therefore,enzyme uti...Many industrial processes may quickly proceed with biotechnological and enzymatic support.Functional and production facilitator properties of enzymes have provided variable advantages for industry.Therefore,enzyme utilization has become inevitable for industry and supplied financial advantages in case of the high energy requirement process.In the study,the amylase enzymes were isolated from thermal spring sources,and the effect on bread quality was examined.Firstly,fungal amylases were isolated from thermal spring sources(29-98◦C)in various places around Turkey.After determining the functional properties of amylase enzymes,the most active enzyme was used in bread production to examine their effect on bread quality.The maximum alpha-amylase activity(38.6 U/mg)has been detected in Aspergillus niger G 2-1 isolate.When compared with the commercially available one,native alpha-amylase increased the bread volume.A significant difference(p<0.01)was found in the color properties and size of the bread between microbial produced in this study and commercially produced alpha-amylase.Five ppm alpha-amylase addition showed the optimum bread properties for dough processing.展开更多
基金Prince of Songkla University(PSU),Hat Yai,Songkhla,Thailand(Grant Number AGR581246S).
文摘The synergistic effect of organoclay(OC)and zinc oxide(ZnO)nanoparticles on the crucial properties of poly(lactic acid)(PLA)nanocompositefilms was systematically investigated herein.After their incorporation into PLA via the solvent casting technique,the water vapor barrier property of the PLA/OC/ZnOfilm improved by a maximum of 86%compared to the neat PLAfilm without the deterioration of Young’s modulus or the tensile strength.Moreover,thefilm’s self-antibacterial activity against foodborne pathogens,including gram-negative(Escherichia coli,E.coli)and gram-positive(Staphylococcus aureus,S.aureus)bacteria,was enhanced by a max-imum of approximately 98–99%compared to the neat PLAfilm.Furthermore,SEM images revealed the homo-geneous dispersion of both nano-fillers in the PLA matrix.However,the thermal stability of thefilm decreased slightly after the addition of the OC and ZnO.Thefilm exhibited notable light barrier properties in the UV-Vis range.Moreover,the incorporation of a suitable biodegradable plasticizer significantly decreased the Tg and notably enhanced theflexibility of the nanocompositefilm by increasing the elongation at break approxi-mately 1.5-fold compared to that of the neat PLAfilm.This contributes to its feasibility as an active food packa-ging material.
文摘This study investigates the tenderizing effects of bromelain extract (BE) obtained from the top phase of an aqueous two-phase system comprising of 18% PEG 6000–17% MgSO4 in muscle foods. Uniform-sized chunks of beef, chicken, and squid were marinated with different concentrations of BE (0, 3, 7%, and 20%, w/w) for 1 h at room temperature. The physico-chemical and quality characteristics of the marinated samples were determined. Decreases in pH and moisture content were observed in the samples BE treated, but the TCA-soluble peptides content significantly increased (p < 0.05). Water holding capacity and cooking yields were observed in all of the tested samples, especially when the concentration of BE increased. In addition, a reduction of meat firmness and toughness were also observed in all of the samples when compared to the control (p < 0.05). Electrophoretic patterns also revealed extensive proteolysis and a reduction in number and intensity of the protein bands in all of the treated samples. At the microstructural level, tissue fibers were broken, cell membranes were more strongly degraded, the connections between the sarcolemma and the myofibrils were disappeared, and the generation of numerous gaps could be clearly observed when 20% (w/w) BE was added. The results show that the bromelain extract derived from the two-phase extraction of a pineapple peel could be used as an effective meat tenderizer.
基金Supported by the Commission for Higher Education,Ministry of Education of Thailand and Faculty of Science,Mahidol University。
文摘Tapioca is economical crop grown in Thailand and continues to be one of the major sources of starch.Nowadays,tapioca starch has been widely used in industrial applications,however the native form of starch has limited the applications.Thus scientists try to modify the properties of starch for increasing the stability of the granules,pastes to low pH,heat,and shear during the food process.We modify the tapioca starch by plasma treatment under an argon atmosphere.The degree of modification is determined by following water content in the starch granules.The tablet samples of native starch are also prepared and compared with the plasma treated starch.Before plasma treatment,the starch tablets are stored under three different relative humilities(RH)including 11%,68%,and 78%RH,respectively.The samples are characterized using FTIR spectroscopy associated with the degree of cross-linking.The results show that the water molecules are engulfed into the starch structure in two ways,a tight bond and a weak absorption of water molecules which is represented at two wave number of 1630 cm^(-1) and 3272 cm^(-1),respectively.The degree of cross-linking can be identified from the relative intensity of these two peaks with the C–O–H peak at 993 cm^(-1).The results show that the degree of cross-linking increase in the plasma treated starch.The degree of cross-linking of the treated starch with high relative humidity is less than that of the treated starch with low relative humidity.
基金the General Directorate of Agricultural Research and Policies for supporting the project“Investigation of Using Potential of Thermal Sourced Native Fungal Alpha Amylase Enzyme in Improving Bread Quality Using Biotechnological Processes”numbered with TAGEM/HSGYAD/16/A05/P01/103.
文摘Many industrial processes may quickly proceed with biotechnological and enzymatic support.Functional and production facilitator properties of enzymes have provided variable advantages for industry.Therefore,enzyme utilization has become inevitable for industry and supplied financial advantages in case of the high energy requirement process.In the study,the amylase enzymes were isolated from thermal spring sources,and the effect on bread quality was examined.Firstly,fungal amylases were isolated from thermal spring sources(29-98◦C)in various places around Turkey.After determining the functional properties of amylase enzymes,the most active enzyme was used in bread production to examine their effect on bread quality.The maximum alpha-amylase activity(38.6 U/mg)has been detected in Aspergillus niger G 2-1 isolate.When compared with the commercially available one,native alpha-amylase increased the bread volume.A significant difference(p<0.01)was found in the color properties and size of the bread between microbial produced in this study and commercially produced alpha-amylase.Five ppm alpha-amylase addition showed the optimum bread properties for dough processing.
