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关键词： characterization   extraction   polysaccharide   properties  

摘要： The polysaccharide from purple sweet potato (PPSP) was extracted. The structure was characterized and partial physicochemical properties were described of PPSP via UV, IR, NMR, XRD, DSC-TGA, LDS, and Congo red assay. This study provided a theoretical basis for the in-depth structural analysis of PPSP and the study of its biological activity.

关键词： Frying   Oil uptake   Phenolic acids   Plantain chips   Post-frying cooling  

摘要： The effects of pressure (21.3, 41.3, 61.3, 81.3, and 101.3 kPa) and temperature (174-184 degrees C) applied during the post-frying centrifuge stage on the physico-chemical characteristics of atmospheric fried plantain chips were studied. Results showed that the surface temperature dropped very fast during the cooling process while the total oil content gradually increased. The oil uptake in the plantain chips increased by 7.7% after 9 min of post-frying cooling. Though an alteration in moisture and oil content was significantly affected (p < 0.05) by either vacuum pressure or temperature control applied during the post-frying centrifuge step, a higher reduction (p < 0.05) of moisture content by 79.1% and total oil content by 44.9% was observed when the combination of vacuum pressure (21.3 kPa) and temperature control was employed, comparing to the control of atmospheric pressure (101.3 kPa). Plantain chips centrifuged under vacuum pressure at 21.3 kPa without temperature control had higher total extractable phenolic acids and lower acrylamide content when compared to control sample. A reduction of pressure alone produced lighter color, higher crispness, and less volume shrinkage of plantain chips;however, no significant difference (p > 0.05) was observed among the samples centrifuged at different pressures. The application of vacuum pressure at 21.3 kPa together with temperature control for 5 min during the post-frying centrifuge stage was significantly effective (p < 0.05) in reducing moisture and oil content, while samples were less crispiness, shrunk more, and a higher bulk density.

关键词： Black rice   Germination process   Heat moisture treatment   Lactic acid bacteria  

摘要： The heat susceptibility of starch granule structure has been considering as significant limitation of germinated black rice (GBR) using in food processing industry. Therefore, this study aimed to improve the physicochemical and antioxidation property as well as its effect on the probiotics of GBR by heat moisture treatment (HMT). Black rice germinated at 37.5 degrees C for 12, 24, and 36 h were studied. Ultrastructural image of each sample was visualized through scanning electron microscope. The results illustrated 24 h-GBR retain its former shape with rough surface. Subsequently, 24 h-GBR was structurally modified by HMT with moisture levels of 20% and 25% for 1 and 2 h. The results showed that pasting properties of HMT-treated GBR were improved. This was particularly on, GBR using HMT condition of 25% moisture for 2 h decrease in breakdown viscosity was shown. Moreover, phenolic content of HMT-treated GBR was higher than those of GBR. Besides, the number of the Lactobacillus paracasei TOKAI 13 was increased in GBR and HMT-treated GBR with counts of 10.08 +/- 0.83 Log CFU/ml and 9.31 +/- 0.33 Log CFU/ml, respectively, with significant increases in antioxidant property. Therefore, the HMT-GBR could be utilized as an alternative functional ingredient in food processing products.

关键词： Ionic liquid   Cyclic lactam   Density   Internuclear distances   Isentropic compressibility   Excess molar volume  

摘要： Excess molar volumes, V-E, excess isentropic compressibilities, kappa(E)(S) of binary 1-butyl-2,3-dimethylimidazolium tetrafluoroborate [C(4)dmim][BF4] (1) + 1-methylpyrrolidin-2-one (NMP) or pyrrolidin-2-one (2-py) (2) and ternary 1-ethyl-3-methylimidazolium tetrafluoroborate [C(2)mim][BF4] or [C(4)dmim][BF4] (1) + NMP (2) + 2-py (3) mixtures have been determined from measured densities and speeds of sound at 293.15, 298.15, 303.15 and 308.15 K. V-E and kappa(E)(S) have been fitted to Redlich-Kister (binary, ternary mixtures) and Cibulka (ternary mixtures) equations respectively. Binary, ternary parameters and standard deviations between the experimental and calculated V-E and kappa(E)(S) values have been computed. Molecular interactions have been characterized qualitatively and quantitatively. IR studies and quantum concepts also support the presence of proposed molecular interactions.

关键词： Surimi gel   Green tea extract   In vitro digestion   Peptide content   Antibacterial activity  

摘要： This study investigates the interaction of fish oil-protein and phenolic-rich green tea extract on the physicochemical quality, lipid oxidation and bacteriostatic properties of different treatments of surimi gel incorporated with fish oil (FO) and Pseuderanthemum palatiferum freeze-dried powder (PFP). The incorporation of 3-6% FO, and 100-200 mg PFP/100 g surimi were investigated. The effect of PFP on the FO-fortified surimi gel had a positive effect on the textural and bio-potential properties. FO-PFP samples showed a higher water-holding capacity than the control gel. Fourier transform infrared spectroscopy (FT-IR) analysis of the surimi gel confirmed the successful blending of oil-protein and phenolic compounds present in PFP. The antioxidant activity and oxidative stability of PUFA-enriched oil increased with the addition of FO-PFP;moreover, the addition of PFP showed good antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Listeria monocytogenes. Hence, the combination of small amounts of PFP in oil-emulsified surimi gel could help in obtaining good-quality surimi gel fortified with health-beneficial polyunsaturated fatty acids that have antibacterial properties.

关键词： Permeate flux   Total energy consumption   Lycopene content   Vitamin C content   Ceramic membrane  

摘要： In this study, the simultaneous effect of fluid pressure, vacuum pressure, and fluid temperature in the microfiltration process of tomato juice was investigated. For this purpose, a microfiltration device with a ceramic filter under pressure-vacuum combination was developed. Next, the effects of the device variables were investigated and optimised in the tomato juice microfiltration process. The results showed the statistically significant effects of fluid pressure, vacuum pressure, and fluid temperature on permeate flux response and total energy consumption. Also, they showed the effects of fluid pressure and fluid temperature on the response variables of lycopene and vitamin C content of tomato juice microfiltration. The optimal conditions of the microfiltration process of tomato juice were achieved at a fluid pressure of 200 kPa, the vacuum pressure of 5 kPa, and fluid temperature of 26 degrees C with a desirability index of 0.967. Under the optimal conditions, values of response variables including permeate flux, total energy consumption, lycopene, and vitamin C content of tomato juice filter were 215.09 x 10(-6)m(3)m(-2)s(-1), 0.044 kWh, 2.42 mg100 g(-1), and 13.21 mg 100 g(-1), respectively. Overall, this type of tomato juice microfiltration, in addition to preserving the valuable nutrients of tomato juice, can cause high permeate flux and low process energy consumption. (C) 2021 IAgrE. Published by Elsevier Ltd. All rights reserved.

关键词： Bacillus amyloliquefaciens   Hydrophobic pellicle   Extracellular polymeric substances   Biofilm architecture   Extracellular fibers  

摘要： Bacillus amyloliquefaciens is a ubiquitous soil and plant-associated bacterial species which shows structural and adaptative responses to the environment. This present paper explores the ability of the strain L-17 to form subaerial biofilms on a liquid surface. Hydrophobic and non-wetting properties were observed for the rough top biofilm layer in contact with the air, which are quite different to the hydrophilic properties which were observed for the smooth biofilm layer in contact with the liquid. Both pellicle interfaces were visualized by scanning electron microscopy revealing a complex three-dimensional architecture composed of exopolymers organized in stacked fibrous network or sheet-like structures in the vicinity of the subaerial surface. Disruption of the extracellular matrix by combining physical and chemical treatments indicated that both loosely and tightly bound polysaccharides were found as major components of this complex pellicle. Proteins were also involved in the aggregation and cohesion of the matrix as multi extraction steps were needed to recover some tightly bounded proteins. This was confirmed by applying protease treatment which was able to significantly disrupt the pellicle. Overall results underline the ability of B. amyloliquefaciens L-17 to survive on air-liquid interfaces. This feature offers an interesting strategy to escape aquatic environments and develop aerial biofilm in response to environmental changes involving wet-dry cycles. (c) 2021, The Society for Biotechnology, Japan. All rights reserved.

关键词： fermented zaopei   physicochemical parameters   microbial community   high-throughput sequencing   flavor substances  

摘要： BACKGROUND: Strong-flavor baijiu is a traditional distilled alcoholic beverage with a long history in China. The fermented grains play a pivotal role in the production of baijiu. The purpose of this study was to evaluate and compare the microbiota and flavor substances present in fermented zaopei (ZP) from pits of different ages. High-throughput sequencing, headspace solid-phase microextraction gas chromatography-mass spectrometry, principal component analysis, community composition analysis, and redundancy analysis were used to analyze and evaluate the impact of environmental factors on microbial communities and flavor substances. RESULTS: Six genera of bacteria (e.g., Caproiciproducens, Syntrophaceticus, Sedimentibacter, Hydrogenispora, Pelotomaculum and Bacillus) and seven genera of fungi (Cladosporium, Debaryomyces, Dipodascus, Auxarthron, Cephalotrichum, unclassified Stachybotryaceae, unclassified Microascaceae and Cephalotrichum) notably affected the production of hexanoic acid (an important flavor compound). Moisture and alcohol content also had considerable effects on the production of the flavor compounds such as ethyl lactate, hexanoic acid, and ethyl hexanoate. The profiles of volatile compounds present in ZP were different between the aged and new pits;these profiles were mainly reflected in the concentration and types of alcohols, aldehydes, esters, and aromatic compounds. CONCLUSIONS: This paper provides a comprehensive overview of the physicochemical parameters, flavor substances, and microbial population distribution of ZP. Characterization of various ZP samples help to elucidate the fermentation mechanisms and offer a theoretical reference to control and enhance the quality of Baijiu. (c) 2021 Society of Chemical Industry.

关键词： Ternary systems   Polysorbate 60   Fatty alcohols   Rheology   Microscopy   DSC   Molecular dynamics  

摘要： The structure and stability of ternary systems prepared with polysorbate 60 and various combinations of cetyl (C16) and stearyl (C18) alcohols were examined as they aged over 3 months at 25 degrees C. Rheological results showed that the consistency of these systems increased initially during roughly the first week of aging, which was succeeded by little changes in consistency (systems containing from 30% to 70% C18, with the 50% C18 system showing the highest consistencies) or significant breakdown of structure (remaining systems). The formation and/or disintegration of all ternary systems were also detected by microscopy and differential scanning calorimetry experiments. This study emphasizes the fact that the structure and consistency of ternary systems are dominantly controlled by the swelling capacity of the lamellar gel phase. Molecular dynamics simulations were performed to provide details on the molecular mechanism of stability. Computational results support the hypothesis experimentally proposed for the stability of the mixed system being due to an increased flexibility of the alcohol with a longer hydrocarbon chain. Computational results are in excellent agreement with experimental conclusions. Additionally, they show that in the mixed system, alcohols with shorter hydrocarbon chain become more rigid. These molecular details could not be available in experimental measurements.

关键词： Structural study   Vibrational study   Thermal analysis   Phase transitions  

摘要： A new mixed compound, sodium rubidium phosphate tellurate, was elaborated using the slow evaporation method at room temperature, confirmed by X-ray single-crystal diffraction. The single-crystal X-ray diffraction structure of Na2.64Rb0.36PO4 center dot Te(OH)(6) is identified for the first time. At 298 K, structural analysis indicates that this compound crystallizes in the monoclinic system with P6(3) space group. The main feature of these atomic arrangements lies in the coexistence of two different anions (PO43- and TeO66- groups) in the unit cell, connected by hydrogen bonds which build up the crystal. The O-H center dot center dot center dot O hydrogen bonds between Te(OH)(6) octahedrons and PO4 tetrahedral contribute to the cohesion and the stability of the atomic arrangement. The Na et Rb atoms are intercalating between their planes. The Fourier transform infrared spectrum exhibited characteristic bands corresponding to the tellurate and phosphate group. Thermal studies were carried out to examine the obtained material and yielded the presence of three phase transitions. The protonic conduction phase transition due to the presence of the breaking of O-H center dot center dot center dot O hydrogen bonds, was regarded as a technologically significant aspect for the new compound. These results corroborate that the new phosphate tellurate can be considered as a promising material in terms of enacting fruitful and constructive applications in advanced technology. The crystal structure was built up from corner-sharing TeOH6 octahedrons, which intercalated by PO4 tetrahedral units. These two groups are connected by hydrogen bonds which make up the building of the crystal, and the Na et Rb atoms are sandwitched between tetrahedral and Te(OH)(6) octahedral planes.