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关键词： Cellulose   Sodium lignosulfonate   Regeneration   Crosslinking structure  

摘要： A homogeneous alpha-cellulose film was prepared by a regeneration method from ZnCl2/CaCl2/cellulose mixed system and was further combined with sodium lignosulfonate (SLS) via crosslinking through intermolecular hydrogen bonds and "bridge linkages". The physicochemical and antibacterial performance of prepared films were investigated and results showed that the modified film exhibited stronger tensile strength, higher thermal stability, lower hydrophilic effect, better UV shielding as compared with the original one, and especially, better antibacterial ability derived from the presence of phenolic hydroxyl and sulfonate groups in SLS. This study proposed a simple and sustainable method for fabricating a multifunctional and environmentally friendly composite film using two main lignocellulose resources as raw materials. [GRAPHICS] .

关键词： Doenjang   Meju   Physicochemical factor   High-throughput sequencing   Microbial community  

摘要： Doenjang, a traditional Korean soybean paste consisting of fermented meju has been consumed for centuries as a protein source. In this study, the physicochemical factors and microbial communities of samples prepared from four batches of meju and doenjang were investigated to identify the factors that affect the food quality. The water content and salt concentration were higher in doenjang than in meju, and the acidity and amino-type nitrogen varied depending on the batch. After fermentation of doenjang, the pH, salt concentration, and amino-type nitrogen increased in all batches. Enterococcus and Bacillus were present in all meju samples, whereas Enterococcus, Tetragenococcus, and Bacillus were present in all doenjang samples. The dominant fungi in meju and doenjang was Aspergillus. The abundance of certain fungi, such as Debaryomyces, Candida, Mucor, and Gibberella, varied batch to batch. The amino-type nitrogen, which determines the quality of doenjang, was correlated with the relative abundance of Aspergillus in doenjang prior to fermentation. In addition, these strains had a negative correlation with the salt concentration. This study has elucidated the composition of microbial communities in meju and doenjang, which may lead to improved quality in the production of fermented food.

关键词： Polysaccharides   Degradation   Anti-inflammatory activity   H2O2   UV  

摘要： There are few studies on seaweed polysaccharides with UV/H2O2 treatment, so the aim of this study was to evaluate the effects of UV/H2O2 treatment on physicochemical properties and RAW 264.7 cells responses of polysaccharides from Sargassum fusiforme (PSF). Results showed that the contents of reducing sugar and sulfate in PSF with UV/H2O2 treatment for 2 h increased by 202.86% and 31.77%, respectively, and the contents of total sugar, protein and uronic acid decreased by 14.29%, 57.11% and 43.18% compared with those of original polysaccharides. In addition, UV/H2O2 treatment did not change the monosaccharide types of original polysaccharides, but it could change its monosaccharide composition and surface morphology. Besides, polysaccharides after UV/H2O2 treatment for 0.5-2 h had lower toxicity than original polysaccharides in RAW 264.7 cells. Typically, PSF with UV/H2O2 treatment for 2 h (PSF-T2) could effectively inhibit pro-inflammatory molecules production (including NO, IL-1 beta, IL-6 and TNF-alpha), and down-regulate related genes expression (including Tlr4, Irak, Il-1 beta, Il-6, Il-12 and Tnf-alpha). Therefore, UV/H2O2 treatment is a potential way to prepare polysaccharide with better anti-inflammatory activity.

关键词： Edible larvae   Insect oil   Astrocaryum vulgare   Oleic acid   Biolipids   Non-solvent extraction  

摘要： A novel insect oil (SRO) from Speciomerus ruficornis Germar larvae was obtained by artisanal non-solvent extraction and its physicochemical properties were investigated. The SRO presented low levels of acidity and peroxides, which is an indication of good quality and conservation standards. The composition of fatty acids showed major content of oleic (32.2%), lauric (21.3%), myristic (19.0%) and palmitic (17.6%) acids. The nutritional quality of its lipid fractions was evaluated through the atherogenicity (similar to 3.1) and thrombogenicity (similar to 2.2) indices, hypocholesterolemic/hypercholesterolemic (1.0) ratio, and calculated oxidability value (similar to 0.82). SRO presented significant amounts of polyphenols, similar to 56 mu g GAE mL(-1) of oil, and a relevant antioxidant capacity, similar to 42 mu g TE g(-1) of oil, which could offer protection against oxidative agents. The FTIR spectra revealed high intensity bands ranging between 2924 and 2854 cm(-1) and 1745 cm(-1), related to the functional groups from long-branched fatty acids and triglycerides. The SRO presented great thermal behavior determined through thermogravimetric and differential scanning calorimetry analysis, which displayed peak temperature at similar to 388 degrees C and an endothermic peak around 10 degrees C related to crystallization of SFAs, respectively. The results of this study shows that SRO is an interesting solvent-free source of fatty acids with significant antioxidant capacity and good thermal behavior. Furthermore, different technologies to obtain SRO can be thought to increase its valuable application as a butter-like product in the food.

关键词： Perilla seed   Storage   Relative humidity   Oil yield   Quality  

摘要： (T)his work investigated the effect of different relative humidity (RH) on the oil yields, physicochemical characteristics, oxidative stability, and microbial safety of perilla seed (PS) stored for 12 weeks. The PSs stored at 11 % RH gave the highest oil yield (34.24 g/100 g PSs), about 7.5-times higher compared with the yield from PSs stored at 93 % RH. During storage at 69-93 % RHs, the lightness (L*) decreased and the redness (a*) and yellowness (b*) increased, indicated a dark-brownish color. The PSs stored at 33-43 % RHs had higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (85.74 %) and iodine value (190 g/100 g sample) and lower acid value (1.40 mg KOH/g sample) and peroxide value (4.35 meq/kg sample) as compared with other PSs samples. During storage, the aerobic bacterial contents (3.08 log10 cfu/g) in PSs were plateaued at 11-69 % RHs, and significantly increased at 81-93 % RHs. Yeasts and molds were found only for those of the PSs stored at 69-93 % RHs. At higher RH (81-93 %), the microbial contents were uncountable due to too much growth after two weeks. This study could be useful for an appropriate storage condition to maintain quality in terms of oxidative stability and retarding microbial growth of PS.

关键词： Cold storage   pH shift   Myofibril protein   Gelation   Rheology   Microstructure   Seafood   Surimi  

摘要： Microbial, physicochemical, rheological, and microstructural changes of surimi prepared by pH shift methods and the traditional water-washing method during cold storage were investigated. The starting aerobic mesophilic count (AMC) of pH shift surimi was around 1 log CFU/g lower than water-washed surimi, suggesting antimicrobial effects of the pH shift. All samples could be stored for 5 to 6 days based on the AMC results. Throughout the storage, the gel strength of alkaline-treated surimi increased from 204.2 to 491.9 g, while water-washed surimi decreased from 462.1 to 172.9 g. After the storage, alkaline-treated surimi showed lower total volatile basic nitrogen (TVB-N) value and smaller network hole size that was suitable for incorporation of moisture and starch. It also remained its rheological properties comparing with acid-treated surimi, with better odour properties, less protein degradation, and better network formation. The results indicate that alkaline-treated surimi is more suitable for cold storage.

关键词： Disposable baby diapers   WXRDF   FTIR   XRD   pH   turbidity   colour  

摘要： Diapers are reusable waste. This research presents physicochemical properties of sodium polyacrylate in new (ND) and used (UD) diapers, via wavelength-dispersive X-ray fluorescence (WDXRF), Fourier transform infrared (FTIR), X-ray diffraction (XRD), pH, turbidity and colour. Additional constituents detected in ND, while others were slightly higher in UD. Slight decrease (2000-2500 cm- 1, UD) and bulk peaks (3287-3333 cm- 1, UD) were observed and functional group at 2897 cm- 1 (ND) disappeared showing their role as absorption sites. The pH (6.83-8.50), turbidity (16.3-36.6 NTU) and colour (153-432 ***) values were obtained. Thus, this provides a baseline reference for diapers application in concrete technology.

关键词： Antioxidant activity   Riceberry flour   Cheese   Cracker   Gastrointestinal transit  

摘要： This study aimed to develop a gluten-free cracker by substituting wheat flour (WF) with riceberry flour (RB) combined with cheese's milk proteins to replace gluten. The effect of substitution of WF with RB at 50 and 100% (RB50 and RB100, respectively) on cracker properties were evaluated. The results showed that water activity, hunter colour value (L*), hardness, and thickness decreased with an increase in the RB content. This related to a compact structure and a weaker crystallinity of RB cracker when compared with WF-based cracker. The substitution of WF with RB50 and RB100 in cracker significantly (P < 0.05)increased the phytochemical content resulting in increased antioxidant *** synergistic effect of the bioactive compound of RB and the bioactive peptides originating from cheese's milk proteins on antioxidant capacity was observed under simulated GI digestion. The greatest increase in the ABTS(center dot+) radical scavenging activity and reducing power was observed in the RB100 cracker at the intestinal digestive phase with the values of 15.74 +/- 0.27 and 3.70 +/- 0.06 mg Trolox eq./g sample, respectively. The results suggest that the substituted 100% RB combined with cheese's milk proteins have a potentiality to be developed into a novel gluten-free product with enhanced antioxidant properties.

关键词： Zeolite   Porous material   Pore size   Water adsorption   Positron annihilation lifetime spectroscopy  

摘要： A systematic study of the influence of surface acidity of pores, water content, crystal size and structural type of zeolites on positronium behavior was carried out over a wide range of Si/Al ratios using the positron annihilation lifetime spectroscopy technique. A clear decrease in the ortho-positronium pick-off annihilation lifetime, as well as the total ortho-positronium formation fraction, was detected at lower Si/Al ratios due to the positronium oxidizing effect and positron trapping of the Bronsted acid sites. Upon water adsorption, the suppression of the positronium diffusion by the water molecules adsorbed in the tubular pores and their trapping action of positrons and electrons was found to significantly reduce both the ortho-positronium lifetime and intensity. These results clarified the relation between positronium behavior and the chemical reactivity of the zeolite pores.

关键词： Cassava roots   Freezing   Functional properties   Starch   Pasting  

摘要： Spoilage of cassava root begins immediately after harvest, but its shelf-life could be enhanced by adopting freezing as a storage method. This study investigated the physicochemical properties and morphology of starch isolated from cassava roots frozen for 0, 7, 14, 21 and 28 days. Extracted starches can be categorized as compound starches with most granules irregularly shaped, with some oval, round and truncated. The amylose contents (22.05-26.41%) decreased with an increase in the freezing time, but the starches showed similar crystallinity pattern (Type A). Fourier infrared transform spectroscopy showed a reduction in double-helical order structure of starches from frozen cassava roots. Starches from the stored roots were generally less firm, less sticky, more cohesive and had higher peak and trough viscosities compared to starch from freshly harvested roots. Starch from frozen cassava starch may be suited for use in certain types of noodles, such as Japanese noodles due to low amylose content. Future studies are however, required to explore the starches in food applications.