Konjac is an ideal candidate for edible coatings on fruits due to its hydrophilic properties,film-forming ability,barrier properties,safety,and biodegradability.Meanwhile,the high market demand for strawberries necessi...Konjac is an ideal candidate for edible coatings on fruits due to its hydrophilic properties,film-forming ability,barrier properties,safety,and biodegradability.Meanwhile,the high market demand for strawberries necessitates post-harvest treatment to extend their shelf life and preserve their quality,as strawberries are known for their fragile skin and soft texture.To fully utilize konjac and develop high-quality coatingfilms,native konjacflour(NKF)and konjac glucomannan(KGM)were extracted from its corm and used as a coatingfilm for strawberries in the present study.Therefore,this study aimed to compare the physical properties of thefilm coatings between NKF and KGM,and evaluate their effects on strawberries preservation over 7 days of storage.A multistage extrac-tion process was employed to isolate NKF and KGM,after which the glucomannan content was measured.NKF yield was 31.81%,exceeding KGM yield of 26.42%,and the glucomannan content obtained of NKF(25.93%)was higher than KGM(21.41%).Nuclear magnetic resonance spectroscopy confirmed that both NKF and KGM con-tain glucomannan in their structure.Furthermore,both NKF and KGM were combined with carboxymethyl cel-lulose(CMC)and glycerol to produce eight thin-layerfilms to assess their physical and mechanical properties.Compared to the KGM variant,the NKF variant generally exhibited higher moisture content,water vapor trans-mission rate,and tensile strength.However,NKF was less effective than KGM in extending strawberry storage life,leading to faster color changes and greater weight loss,despite maintaining similar hardness values.Nonetheless,konjac-based coatings were generally effective at maintaining the freshness and quality of strawberries compared to uncoated samples.Konjac shows promise as an edible coating,improving fresh produce shelf life and appeal,aligning with consumer preferences for natural and sustainable products.展开更多
Nanocellulose-based adhesives are gaining attention as a viable alternative to conventional adhesives,offering benefits such as cost-effectiveness and scalability,which make them suitable for various sectors,including...Nanocellulose-based adhesives are gaining attention as a viable alternative to conventional adhesives,offering benefits such as cost-effectiveness and scalability,which make them suitable for various sectors,including cosmetics,pharmaceuticals,biodegradable products,and as reinforcing agents in natural adhesives.This review delves into the current advancements in nanocellulose-based adhesive solutions for sustainable and eco-friendly wood composites,using systematic review methods and bibliometric analysis.Data were collected from the Scopus database,spanning from 2007 to 2024,and visualized using VOSviewer to highlight emerging trends in the field.The analysis revealed that nanocellulose shows great potential as a reinforcing component for traditional adhesives used in wood products such as phenol-formaldehyde(PF),urea-formaldehyde(UF),polymeric diphenylmethane diisocyanate(pMDI),and melamine-urea adhesives.Nanocellulose,derived from the most abundant biopolymer,cellulose,has been utilized in its nanoscale form for adhesive applications.This review emphasizes the advancements in using cellulose nanocrystals(CNC)and cellulose nanofibrils(CNF)to develop sustainable adhesives.It explores both the challenges and future prospects for large-scale production and application of nanocellulose-based adhesives.展开更多
Following the natural structure of the nacre,the material studied consists of a multitude of hexagonal tiles that are glued together in an offset manner with a ductile adhesive.This so-called“wood nacre”consists of ...Following the natural structure of the nacre,the material studied consists of a multitude of hexagonal tiles that are glued together in an offset manner with a ductile adhesive.This so-called“wood nacre”consists of macroscopic tiles of birch wood veneer with a thickness of 0.8 mm and a size of 20 or 10 mm in diameter in order to mimic the aragonite tiles and the ductile PUR-adhesive corresponds to the layers of collagen in between.E-modulus(MOE),bending strength(MOR)and impact bending strength of the samples were determined and compared with reference samples of birch laminated wood.The hierarchical layered structure of the tiles does not cause any relevant loss in stiffness.Like nacre,“wood nacre”also shows tough fracture behaviour and a high homogenization effect.However,strain hardening and high fracture toughness of the natural model could not be fully achieved.The reason for this is the insufficient ratio between the strength and stiffness of the veneer layers and the adhesive.By adjusting the size of the tiles,increasing the strength and surface roughness of the veneers,e.g.by densification,and using more ductile adhesives that can be applied in smaller layer thicknesses,it should be possible to better reproduce the natural ratios of nacre and thus achieve a significant improvement in the material properties of“wood nacre”.In addition to the mechanical properties,the high potential of the new material lies in the possibility of producing 3D shell-shaped elements for lightweight wood hybrid construction.展开更多
Methane potential of three-phase olive mill solid waste(3POMSW)was evaluated by biochemical methane potential(BMP)tests at temperatures of 37.5◦C and 55◦C.The results have shown,that thermophilic processing has a high...Methane potential of three-phase olive mill solid waste(3POMSW)was evaluated by biochemical methane potential(BMP)tests at temperatures of 37.5◦C and 55◦C.The results have shown,that thermophilic processing has a higher methane and biogas yield by 10%and 17.2%,respectively,compared to mesophilic conditions.Concluding thermophilic conditions of 3POMSW results in higher conversion of the feedstock into biogas.The result of addition of enzymes(MethaPlus,Hemicellulase,PectinaseL,Amylase S and Lipase)and their mixtures to 3POMSW at 55◦C has shown that the optimum mixture of enzymes was Metha Plus and Hemicellulase,which resulted in an increase of methane yield by 1.3%compared to the base case without addition of enzymes.Simple model equations were developed based on first-order kinetic in order to calculate the biogas yield versus the time as a function of reaction rate constant(k)and the maximum biogas yield(ymax).In this study,results have shown two different reaction rates obtained for the mixtures of enzymes with 3POMSW of 0.130 d^(-1) from t=0…14 days and 0.034 d^(-1) from t=28…63 days.The developed simple model equations can be applied for calculating the biogas yield at the time and by optimizing the process improving biological nutrient removal.展开更多
基金funded by the Academic Leadership Grant of Universitas Padjadjaran,Bandung,Indonesia,with grant number 1540/UN6.3.1/PT.00/2024the Research Collaboration Center for Biomass and Biorefinery,Bandung,Indonesia,with grant number B-1723/II.7/HK.01.00/4/2024.
文摘Konjac is an ideal candidate for edible coatings on fruits due to its hydrophilic properties,film-forming ability,barrier properties,safety,and biodegradability.Meanwhile,the high market demand for strawberries necessitates post-harvest treatment to extend their shelf life and preserve their quality,as strawberries are known for their fragile skin and soft texture.To fully utilize konjac and develop high-quality coatingfilms,native konjacflour(NKF)and konjac glucomannan(KGM)were extracted from its corm and used as a coatingfilm for strawberries in the present study.Therefore,this study aimed to compare the physical properties of thefilm coatings between NKF and KGM,and evaluate their effects on strawberries preservation over 7 days of storage.A multistage extrac-tion process was employed to isolate NKF and KGM,after which the glucomannan content was measured.NKF yield was 31.81%,exceeding KGM yield of 26.42%,and the glucomannan content obtained of NKF(25.93%)was higher than KGM(21.41%).Nuclear magnetic resonance spectroscopy confirmed that both NKF and KGM con-tain glucomannan in their structure.Furthermore,both NKF and KGM were combined with carboxymethyl cel-lulose(CMC)and glycerol to produce eight thin-layerfilms to assess their physical and mechanical properties.Compared to the KGM variant,the NKF variant generally exhibited higher moisture content,water vapor trans-mission rate,and tensile strength.However,NKF was less effective than KGM in extending strawberry storage life,leading to faster color changes and greater weight loss,despite maintaining similar hardness values.Nonetheless,konjac-based coatings were generally effective at maintaining the freshness and quality of strawberries compared to uncoated samples.Konjac shows promise as an edible coating,improving fresh produce shelf life and appeal,aligning with consumer preferences for natural and sustainable products.
基金funded by the Research Collaboration Center for Biomass and Biorefinery,Universitas Padjadjaran and BRIN,Indonesia,Grant Number 2534/II.7/HK.01.00/5/2023 and B-723/II.7/HK.01.00/4/2024.
文摘Nanocellulose-based adhesives are gaining attention as a viable alternative to conventional adhesives,offering benefits such as cost-effectiveness and scalability,which make them suitable for various sectors,including cosmetics,pharmaceuticals,biodegradable products,and as reinforcing agents in natural adhesives.This review delves into the current advancements in nanocellulose-based adhesive solutions for sustainable and eco-friendly wood composites,using systematic review methods and bibliometric analysis.Data were collected from the Scopus database,spanning from 2007 to 2024,and visualized using VOSviewer to highlight emerging trends in the field.The analysis revealed that nanocellulose shows great potential as a reinforcing component for traditional adhesives used in wood products such as phenol-formaldehyde(PF),urea-formaldehyde(UF),polymeric diphenylmethane diisocyanate(pMDI),and melamine-urea adhesives.Nanocellulose,derived from the most abundant biopolymer,cellulose,has been utilized in its nanoscale form for adhesive applications.This review emphasizes the advancements in using cellulose nanocrystals(CNC)and cellulose nanofibrils(CNF)to develop sustainable adhesives.It explores both the challenges and future prospects for large-scale production and application of nanocellulose-based adhesives.
文摘Following the natural structure of the nacre,the material studied consists of a multitude of hexagonal tiles that are glued together in an offset manner with a ductile adhesive.This so-called“wood nacre”consists of macroscopic tiles of birch wood veneer with a thickness of 0.8 mm and a size of 20 or 10 mm in diameter in order to mimic the aragonite tiles and the ductile PUR-adhesive corresponds to the layers of collagen in between.E-modulus(MOE),bending strength(MOR)and impact bending strength of the samples were determined and compared with reference samples of birch laminated wood.The hierarchical layered structure of the tiles does not cause any relevant loss in stiffness.Like nacre,“wood nacre”also shows tough fracture behaviour and a high homogenization effect.However,strain hardening and high fracture toughness of the natural model could not be fully achieved.The reason for this is the insufficient ratio between the strength and stiffness of the veneer layers and the adhesive.By adjusting the size of the tiles,increasing the strength and surface roughness of the veneers,e.g.by densification,and using more ductile adhesives that can be applied in smaller layer thicknesses,it should be possible to better reproduce the natural ratios of nacre and thus achieve a significant improvement in the material properties of“wood nacre”.In addition to the mechanical properties,the high potential of the new material lies in the possibility of producing 3D shell-shaped elements for lightweight wood hybrid construction.
文摘Methane potential of three-phase olive mill solid waste(3POMSW)was evaluated by biochemical methane potential(BMP)tests at temperatures of 37.5◦C and 55◦C.The results have shown,that thermophilic processing has a higher methane and biogas yield by 10%and 17.2%,respectively,compared to mesophilic conditions.Concluding thermophilic conditions of 3POMSW results in higher conversion of the feedstock into biogas.The result of addition of enzymes(MethaPlus,Hemicellulase,PectinaseL,Amylase S and Lipase)and their mixtures to 3POMSW at 55◦C has shown that the optimum mixture of enzymes was Metha Plus and Hemicellulase,which resulted in an increase of methane yield by 1.3%compared to the base case without addition of enzymes.Simple model equations were developed based on first-order kinetic in order to calculate the biogas yield versus the time as a function of reaction rate constant(k)and the maximum biogas yield(ymax).In this study,results have shown two different reaction rates obtained for the mixtures of enzymes with 3POMSW of 0.130 d^(-1) from t=0…14 days and 0.034 d^(-1) from t=28…63 days.The developed simple model equations can be applied for calculating the biogas yield at the time and by optimizing the process improving biological nutrient removal.
