Cellulose-Based Films for Food Packaging Applications:Review of Preparation,Properties,and Prospects

Packaging is a food preservation technology widely used in the world.Naturally-sourced,biodegradable polymers are becoming increasingly popular in the food packaging sector.Packagingfilms prepared using cellulose as raw material would contribute to resource sustainability,but the difficulty of cellulose solubilization limits their further development.In view of this,a series of novel solvent systems(LiCl/DMAc,ILs,TBAH/DMSO,NMMO,alkali/urea solutions,metal-complex solutions)were used to prepare high-strength and high-performance cellulose-basedfilms;their characteristics and the mechanisms involved were investigated.Compositefilms prepared by blending cellulose with various polymers(synthetic polymers,natural polymers,proteins and enzymes,metal particles,and plant phenols)and their functional properties were also investigated.Problems with cellulose-basedfilms and the outlook for future research are discussed.It is hoped that in the near future high-performance,biodegradable and sustainably-produced cellulose-basedfilms will lead the food packaging industry into a new era and further promote the sustainable use of resources.

Investigation into Spatter Particles and Their Effect on the Formation Quality During Selective Laser Melting Processes

During the selective laser melting process,a high-energy laser beam acts on the powder,a molten pool is rapidly generated and the characteristic parameters are constantly changing.Among them,temperature is one of the important parameters in the forming process.Due to the generation of splash particles,there will be defects in the microstructure,which will seriously affect the formation quality of the prepared parts.Therefore,it is necessary to study the relationships between the splash behavior,molten pool characteristics and product quality.The finite element simulation of the transient temperature field was performed by ANSYS software.Time-series images at different frame rates were obtained with a high-speed camera,and the dynamic process of splashing was observed.Using IN718 alloy powder,the influence of the laser energy density on the light intensity of the molten pool was studied.The appearance of splash particles and the deviation of the powder chemical elements caused by the splash were analyzed.The results show that the transient temperature field with drastic change is easy to cause spatter,which is consistent with the experimental results.There are large differences in the splash at different shooting frame rates.Increasing the frame rate can allow the observation of details such as the shape,size and number of splash particles,which is beneficial for studying the process of splash formation.At the moment when the splash occurs,the light intensity of the molten pool always first increases and then decreases,depending on the energy input.The higher the energy input is,the more intense the light intensity of the molten pool and the higher the peak interval distribution.Compared with fresh powder,the contents of Al and Ti in powder reused 5 times were reduced by 0.15%and 0.02%,respectively.The increases of these two elements in the splash were 16.18%and 29.62%,respectively,and the content of Nb even exceeded the standard range.When the energy density decreased from 229.17 J/mm3 to 130.95 J/mm3,the relative density of the part increased from 91.82%to 99.83%.This shows that reducing the energy input can reduce the splash to suppress the generation of defects,along with the weakening of the overall light intensity of the molten pool.These results can provide a basis for feature extraction of the molten pool,which is of great significance for real-time monitoring and online control in manufacturing processes and ensuring product quality.

Cellulose derived biochar:Preparation,characterization and Benzo[α]pyrene adsorption capacity

Edible oil is prone to be contaminated by Benzo[a]pyrene(BaP)during production and processing.Adsorption is an important technology for the removal of BaP from edible oil,and biochar as a new type of adsorbent for the treatment BaP has received extensive attention.In this study,we prepared unmodified biochar and ZnCl_(2)-modified biochar from sesame straw cellulose(SSB and SSZ)and sesame capsule cellulose(SCB and SCZ),carried out structure characterization by Fourier Transform Infrared(FT-IR),Brunauer-Emmett-Teller(BET)and Scanning Electron Microscope(SEM),and finally evaluated their potential effectiveness in BaP removal from sesame oil.FT-IR results revealed that SSZ and SCZ showed higher peak intensities,indicating that they could provide more active sites for adsorption.The results of XRD presented that SSZ and SCZ had a higher graphitization degree than the unmodified biochar.SEM results showed that the SSZ and SCZ had more complex pore structure,which is beneficial to adsorption.BET analysis results showed that SSZ and SCZ had a higher specific surface area of 1622.83-1797.39 m^(2)/g and a better developed porous structure(the total pore volume Vtotal was 0.9434-1.0023 cm^(3)/g)than the SSB and SCB(specific surface area was 350.55-352.59 m^(2)/g,and Vtotal was 0.1907-0.1918 cm^(3)/g),indicating that modification promoted the formation of porous structure and thus improved the adsorption capacity of biochar.Adsorption experiments confirmed once again that the BaP removal rates of SSZ and SCZ(92.67%-96.13%)were much higher than that of unmodified biochar(3.34%-4.28%),and the BaP content in the sesame oil treated by SSZ and SCZ were far below the current EU maximum levels(2μg/kg).Therefore,the modified biochar from cellulose is a promising adsorbent for BaP removal.In future studies,the influences of bichar on the nutritional quality of edible oil should be taken into consideration so as to find an ideal active carbon substitute for BaP removal in edible oil.

Consumer acceptability and sensory profiling of sesame oils obtained from different processes

This study aimed to investigate the effect of oil processing technologies on the sensory qualities of sesame oils and to identify drivers of liking.Using a check-all-that-apply(CATA)question and a hedonic scale,150 consumers evaluated the acceptability and sensory characteristics of 5 sesame oil samples including an aqueous extracted oil(S1),a cold-pressed oil(S2),two batches of screw-pressed oils(S3 and S5)and one crude sesame oil(S4).Solid-phase microextraction-gas chromatography-olfactometry-mass spectrometry(SPME-GC-O-MS)was used to identify odour-active compounds.The results showed that roasting,extraction techniques and filtration process influenced sensory perception and the acceptability of sesame oils.Consumers liked roasted sesame oils more than the cold-pressed sesame oil and liked the aqueous extracted sesame oil the most.Sensory attributes"sweet smell","mellow","roasted","nutty","persistent","high-intense flavour"and"cooked sesame seed flavour"were drivers of liking,while"green","raw sesame seed","rancid","woody"and"fishy"were drivers of disliking."Burnt"flavour was liked by some while disliked by others.Pyrazines contributed to roasted flavour;2-acetylpyrrole,acetophenone and furfural contributed to nutty flavour;2-pentyl-furan,5-methyl-2-furancarboxaldehyde,and 2-phenyl-2-butenal contributed to sweet odour in the roasted sesame seeds.Nonanal,hexanal,1-hexanol and ocimene were responsible for the"green"flavour perceived in the cold-pressed oil.This study provides valuable information for sesame manufacturers on how to improve the sensory qualities of sesame oils through process manipulation to meet the needs of diverse consumers.

Comprehensive utilization of corn starch processing by-products:A review

Corn is a high starchy cereal crop with the highest production and provides over 85%of the starch produced worldwide.Various by-products,differentiated by technological process features such as steep liquor,corn germ,corn bran,gluten,are created largely during corn starch processing.They are inexpensive,nutrient-rich,and vary widely in chemical composition such as proteins,oils,carbohydrates,and minerals.In an increasingly resource-constrained modern world,the utilization approach of these by-products for non-starch industrial processing is attractive widely considering both nutritive value and economic aspects.In fact,at present,applications of these by-products can often be found in feed,fermentation,nutrient extraction and other industries.For example,protein-rich corn gluten can be used as a good animal feed,and corn germ can be used as a raw material for the high-quality edible oil industry.Undoubtedly,increasing utilization means that these by-products will no longer be treated as waste but will be transformed into high value-added products.In this work,the separation process and chemical composition of several main by-products of the corn starch industry is briefly described,and the application in many industrial fields of these by-products over the last ten years are discussed in particular.This review attempts to summarize all aspects of the application and research of these by-products.For the by-products of the corn starch industry,the most promising way is to be utilized in high value and used to produce high value-added products.According to the characteristics of their chemical composition,they have a better application prospect and research significance in the industries directly related to human beings,such as medicine,green food and health care products.In fact,in recent years,some researchers have recognized this and carried out the research.It is clear fromthese studies that the main issues to be faced nowand in the future are how to produce efficiently while maintaining the quality of the product and using it effectively.The retrospective discussions also provide some ideas for other grain and oilseed crops to be fully utilized.

Difference among the quality indices,chemical composition and frying performance of galangal flavored sunflower oil prepared by three methods

Flavored vegetable oils have attracted more and more attentions from consumers and researchers due to their high oxidative stability and sensory quality.In the present study,the quality indices,chemical composition and frying performance of galangal flavored sunflower oil prepared by infusion method(GFSO-I),combination pressing method(GFSO-C)and direct addition method(GFSO-A)were investigated.The results displayed that the preparation time,the levels for the acid value(AV),peroxide value(PV),p-anisidine value(AnV),total oxidation value(TOTOX),and the values for total polar compounds(TPC),thiobarbituric acid(TBA),K232 and K268 of GFSO-C were prominently low(P<0.05),compared with that of GFSO-I and GFSO-A,while the fatty acid composition of them were similar.In the frying of Chinese Maye(tradional Chinese food,fried dough stick)at 180°C for 30 h,the values for TPC,TBA,K232 and K268,polymer,viscosity and b*of GFSO-C were obviously low(P<0.05),while the value for L*was obviously high(P<0.05),compared with that of GFSO-I and GFSO-A.In the sensory evaluation,the flavor,taste,crispness and overall acceptance of Chinese Maye fried by GFSO-C were better than that of Chinese Maye fried by GFSO-I and GFSO-A.Consequently,GFSO-C is more suitable for cooking,and the combination pressing method is optimal for industrial production of GFSO.

Effect of black and white sesame on lowering blood lipids of rats with hyperlipidemia induced by high-fat diet

Sesamum indicum has various biological effects,and this study aimed to investigate its hypolipidemic effect.A hyperlipidemia rat model was established by feeding rats with high-fat diets in this study,then the hyperlipidemia rats were fed with different doses of black and white sesame seeds and black and white sesame kernels.The serum and liver biochemical indicators of the rats were determined,and liver pathology analysis was conducted to evaluate the hypolipidemic effect of sesame.The results showed that the blood lipid of SD(Sprague-Dawley)rats fed with high-fat diet for three weeks was higher than 200 mg/d L,indicating that the hyperlipidemia rat model was successfully established.At the same dose,the final body weights of the rats of white sesame seed and kernel groups were higher than those of the black sesame seed and kernel groups;and the weights of the black and white sesame seed groups were lower than those of the black and white sesame kernel groups.The liver indexes of the normal control group and the experimental groups were significantly lower than the model control group(P<0.05),indicating that black and white sesame seed and kernel could reduce the lipid accumulation on the liver.The malondialdehyde(MDA)values of the liver in the normal control group and the experimental groups were significantly lower than that in the model control group(P<0.05).The total antioxidant capacity(T-AOC),high density lipoprotein cholesterol(HDL-C),glutathione peroxidase(GSH-Px)and total superoxide dismutase(T-SOD)in the liver of each experimental group were significantly higher than those in the model control group(P<0.05).Based on the above results as well as pathological observation and analysis,we found that the black and white sesame seeds and kernels could improve fatty liver lesions and lipid metabolism disorder and could reduce lipid accumulation on the liver,thereby protecting the liver from damage and reducing the risk of fatty liver.Moreover,black and white sesame seeds,black and white sesame kernels can reduce the levels of total cholesterol(TC)and triglyceride(TG)in serum,and high dose of black sesame seeds(30%black sesame seeds)and low dose of black sesame kernels(10%black sesame kernels)were more beneficial for the recovery of hyperlipidemia and fatty liver.The above results indicated that black and white sesame has hypolipidemic effect.

Critical steps in the production of oil from oilseed to reduce heterocyclic aromatic amines

Contamination by the heterocyclic aromatic amines(HAAs)norharman and harman is one of the risks in vegetable oil production,so oil producers strive to decrease their content in the end products.In this study,the effects of production conditions—specifically,two pretreatment methods(roasting and microwaving),four extraction methods(two pressing and two solvent extraction)and adsorption refining(four absorbents)—of five oils(flaxseed,peanut,rapeseed,sesame,and sunflower seed)were evaluated.The results showed that microwaving as a pretreatment produced significantly fewer HAAs than roasting(P<0.05).After two pretreatments,the HAA content of oils was ranked from high to low as follows:sunflower oil,sesame oil,flaxseed oil,rapeseed oil,and peanut oil.Solvent-extracted oils(9.16–316.73μg/kg)had fewer HAAs than pressed oils(26.61–633.93μg/kg).Using adsorbents reduced HAAs in oils from the initial 21.77–484.22 to 0.31–41.58μg/kg,and the removal rate reached 99.28%.This study provides critical HAA reduction strategies for application in the oil production process to obtain safe final products.

Investigations on femtosecond laser-induced surface modification and periodic micropatterning with anti-friction properties on Ti6Al4V titanium alloy

Titanium alloys have a wide application in aerospace industries as it has greater strength and low density, but it has poor tribological properties. To improve its friction and wear performance, in present work, a femtosecond laser is used to directly irradiate the Ti6Al4V titanium alloy surface in air conditioning, which results in localized ablation and the formation of periodic microstructures but also a strong pressure wave, propagating the material inside. Through the optimization of processing parameters, surface modification and periodic micropatterning with effective anti-friction properties were successfully induced on the surface. After a treatment of femtosecond laser-induced surface modification(FsLSM), the surface microhardness was improved by 16.6% and compressive residual stress reached-746 MPa. Besides, laser-induced periodic surface structures(LIPSS) with a titanium oxide outer coating were fabricated uniformly on the titanium alloy surface. Rotary ball-on-disk wear experiments revealed that the average coefficient of friction(COF) and wear mass loss of the specimen with Fs LSM treatment were largely reduced by 68.9% and 90% as compared to that of untreated specimens, respectively. It was analyzed that the reason for the remarkable wear resistance was attributed to the comprehensive action of the generation of LIPSS, the titanium oxide outer coating, high amplitude compressive residual stress and gradient grain size distribution on the subsurface during the laser surface treatment. Since the findings here are broadly applicable to a wide spectrum of engineering metals and alloys, the present results offer unique pathways to enhancing the tribological performance of materials.

Molecular evolution and species-specific expansion of the NAP members in plants

he NAP（NAC-Like, Activated by AP3/PI） subfamily is one of the important plant-specific transcription factors, and controls many vital biological processes in plants. In the current study, 197 NAP proteins were identified from 31 vascular plants,but no NAP members were found in eight non-vascular plants.All NAP proteins were phylogenetically classified into two groups（NAP I and NAP II）, and the origin time of the NAP I group might be relatively later than that of the NAP II group.Furthermore, species-specific gene duplications, caused by segmental duplication events, resulted in the expansion of the NAP subfamily after species-divergence. Different groups have different expansion rates, and the NAP group preference was found during the expansion in plants. Moreover, the expansion of NAP proteins may be related to the gain and loss of introns.Besides, functional divergence was limited after the gene duplication. Abscisic acid（ABA） might play an important role in leaf senescence, which is regulated by NAP subfamily. These results could lay an important foundation for expansion and evolutionary analysis of NAP subfamily in plants.