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关键词： Physicochemical properties  

摘要： Cactus (Opuntia ficus-indica L.) seed oil, which is extracted from prickly pear fruit seeds, might constitute an alimentary source of substances of nutraceutical value. Physicochemical properties, chemical composition, antioxidant activity, and oxidative stability of prickly pear seed oil prepared from unroasted seeds were evaluated and compared with those of oil that was prepared from seeds roasted for different times. Prolonged roasting time had no significant influence on the protein content of the seeds. However, an increase in total phenolic compounds was observed from 225.9 mg GAE/100 g oil to 362.7 mg GAE/100 g oil after 40 min of roasting at 110 degrees C. Consequently, an increase in antioxidant power which will induce a better oxidation resistance was found by the 1.1-diphenyl-2-picrylhydrazyl method expressed as EC50 value that was reduced from 0.6 to 0.1 mg/ml. No significant change was observed in triacylglyceride and fatty acid composition, whereas tocopherol (512.8 to 542.1 mg/kg after 40 min of roasting) and sterol (8,292 to 8,629 mg/kg after 40 min of roasting) levels increased. Oxidative stability increased remarkably from 3.1 to 7.6 hr after 40 min of roasting with the increase in roasting time. The current study revealed that prickly pear seeds and the resulting oil have excellent nutritional qualities that were significantly elevated after roasting. Practical applications Cactus seed oil is one of the most expensive vegetable oils and roasting of the seeds before pressing can help to improve not only the sensory quality of the oil but also the oxidative stability. Therefore, it is important to know more about the influence of roasting time on the quality of the oil. With this information, it is possible to optimize the roasting process regarding oil stability but also the release of bio-active compounds such as tocopherols or phenolic compounds. Overall, this will significantly improve the acceptance of this oil.

关键词： Kiwifruit   Post-ripening   Microstructure   Cell wall polysaccharide nanostructure   Pectin molecular weight  

摘要： Kiwifruit undergoes rapid softening and quality changes after harvest, which has an important impact on consumer appeal, shelf life and market value. Effects of postharvest ripeness on physicochemical properties, microstructure, cell wall fraction (pectin, hemicellulose and cellulose) contents and nanostructure, and pectin molecular weight were investigated. As the postharvest time increased from 0 to 6 days, the contents of total soluble solid and water-soluble pectin increased by 77.4% and 113.0%, respectively;while the content of starch, water insoluble pectin, and hemicellulose decreased by 89.9%, 46.5%, and 33.5%, respectively. Disappearance of starch granules and the increase of intercellular space were observed using SEM. AFM analysis showed that both hemicellulose and pectin depolymerized gradually during storage. Measurements of the molecular weight confirmed the occurrence of depolymerization and degradation of pectin, while the cellulose content, nanostructure, and diameter of individual microfibrils did not change significantly. The findings in current work revealed the quality evolution and related mechanism of kiwifruit during storage.

摘要： The objective of this study was to develop probiotic beverages, enriched with plant proteins, with high nutritional value. A rice-based beverage fermented with a specific probiotic formulation comprised Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R and Lactobacillus rhamnosus CLR2 has been enriched with a combination of pea and rice proteins (PR) or pea and hemp proteins (PH) at 13 and 11% total protein, respectively. These protein associations have been selected because their amino acid ratio was >1, as recommended by the FAO. The beverage enriched with protein significantly increased its viscosity by more than 10 times thanks to the enrichment, while the fermentation reduced it by 50% for PR and 20% for PH. In vitro protein digestibility results showed that the protein enrichment and the fermentation treatment significantly increased digestibility values of the beverages with value of 72.7% for fermented PR beverage and 61.4% for unenriched fermented control beverage (p <= 0.05). Peptide profiles of PR and PH enriched beverages indicated that the fermentation led to a reduced level of high molecular weight (HMW) peptides of about 60% and an increase of low molecular weight (LMW) peptides by over 50%. Therefore, both the fermentation and the enrichment in protein increased the nutritional value of the rice-based beverages. Practical Application Good quality of probiotics formulation and high-protein products are in increasing demand and plant proteins as an alternative of animal protein are popular. This study has permit to develop rice-based commercial probiotic beverages enriched in a combination of pea and rice or pea and hemp proteins in order to obtain a complete protein in terms of amino acids composition. The lactic acid fermentation and the enrichment with a plant protein combination led to a better protein digestibility of beverage.

关键词： Morus indica   1-Deoxynojirimycin   Resveratrol   Phenolic acids   Flavonoids   HPLC  

摘要： Mulberry fruit is well recognized as one of the richest sources of bioactive compounds. We investigated the physicochemical composition and characterized the bioactive compounds during different ripening stages of mulberry (Morus indica) fruit and evaluated their anti-quorum sensing activity on Chromobacterium violaceum. The proximate components such as carbohydrates, proteins and lipids were found to be high in the ripe fruit compared to unripe and mid-ripe fruit. The ripe fruit contained higher content of total phenolics and flavonoids (336.05 and 282.55 mg/100 g fresh weight (FW), respectively). Epicatechin and resveratrol were the major polyphenols detected in the fruit with the range 5.13-19.46 and 4.07-14.45 mg/100 g FW, respectively. Chlorogenic acid and myricetin were predominant in the unripe and mid-ripe fruit (7.14 and 1.84 mg/100 g FW, respectively). The fruit was found to be an excellent source of anti-diabetic compound 1-deoxynojirimycin. The highest content of 1-deoxynojirimycin was present in the mid-ripe fruit, with a content of 2.91 mg/100 g FW. Furthermore, fruit extracts exhibited anti-quorum sensing activity against Chromobacterium violaceum by effectively inhibiting violacein production. Ripe fruit extracts showed the highest activity of 76.30% at 1 mg/mL and thus, could be used as a potent anti-quorum sensing agent. The results could be promising in the selection of appropriate developmental stages for M. indica fruit commercial exploitation in the food formulations rich in potential health components.

关键词： Sonication  

摘要： The impact of sonication treatment (0, 5, 15, 30, and 60 min) of skim milk concentrates on physicochemical, functional, powder flow behaviour, and microbiological properties of milk powders was investigated. Sonication resulted in higher firmness and consistency of concentrates with increasing treatment time. In milk powders, higher L* and a* values were observed in sonicated samples. D[4,3] parameter of milk powders was between 8.1 and 255.0 mu m, and sonication for 60 min decreased this value. Sonication significantly decreased the caking, cohesion, and compaction properties of samples. The flow stability of sonicated samples was higher than that of the control. Sonication can result in improved flow characteristics of milk powders in terms of caking, cohesion, and compaction. These observations could relate to effects of sonication on casein micelle, whey proteins denaturation, whey/whey or casein/whey aggregation. Sonication of milk concentrates was also effective in reducing the microbial counts of milk powders. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Optical and Electronic Materials   Characterization and Evaluation of Materials  

摘要： For the first time, the synthesis was carried out and the physicochemical properties of solid solutions based on the multiferroic BiFeO3 were studied. It was found that the samples were characterized by a rhombohedrally distorted perovskite structure. It was shown that a slight isovalent substitution of Bi3+ ions by La3+ ions and Fe3+ ions by Co3+ ions in BiFeO3 (x <= 0.10) leads to an increase in the specific magnetization. This can be attributed to structural distortions and causes weak ferromagnetism to occur. The studied samples are p-type semiconductors and have good sensory properties even without catalysts. It was found that the maximum values of the S response were obtained at temperatures close to the ferromagnetic Curie temperature, the value of which is consistent with the studies of electrical properties.

关键词： Polymer Sciences   Surfaces and Interfaces   Thin Films  

摘要： The influence of repeated cryogenic treatment (-20 degrees C for 12 h followed by defrosting at a heating rate of 0.03 degrees C/min) on poly(vinyl alcohol) cryogel (PVACG) samples occurring in a forcedly deformed state (bending, compression, torsion) has been investigated. It has been shown that this action on primary PVACG may be characterized as the secondary molding process, because the cryogel acquires and, further, retains a new geometric shape resultant from deformation. Therewith, the higher the deforming mechanical load, in particular compression force, the higher the rigidity of PVACG resulting from the secondary molding. The study of such cryogels by DSC and wide-angle X-ray scattering has revealed that the secondary molding increases the ordering of the structure of PVA microcrystallites, which have already being present in the nodes of the physical networks of primary cryogels and leads to the appearance of additional zones of microcrystallinity. On the whole, these formations fix the new geometry of the secondary PVACG samples.

关键词： epsilon-Polylysine   Sodium tripolyphosphate   Physicochemical properties   Antibacterial activity   Cooked pork sausage  

摘要： The aim of this study are to investigate the physicochemical and antibacterial properties of sodium tripolyphosphate (TPP)/epsilon-Polylysine(epsilon-PL) complexes. Their physicochemical properties were studied as a function of molar ratios by following changes in turbidity, particle size, and zeta potential. These results showed that the formation of stable and quest-stable complexes in aqueous solution was determined by the molar ratios. Moreover, Fourier Transform Infrared (FTIR) spectroscopy measurement demonstrated that the electrostatic force mainly dominated their complexation. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and molecular dynamics simulation demonstrated that epsilon-PL and TPP molecules interacted and bound together to form a stable complex. In vitro antibacterial activity against Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes, utilizing minimum inhibitory concentration (MIC), inhibition zone and time-kill assay, revealed that the antibacterial activity of R-10 was the strongest. Furthermore, analogous bacterial membrane disruptions were observed in the treatments of complexes and epsilon-PL through scanning electron microscopy (SEM). In the application, cooked pork sausage was inoculated with the above-mentioned three-strain cocktails and stored at 12 degrees C for 6 days, cocktails' total and individual colony counts were periodically monitored. Compared to other treatments, R-10 behaved significantly different in all of the colony counts. Overall, this study confirmed that the antibacterial vehicle based on the TPP/epsilon-PL complex has a potential utilization in food application and pharmaceutics expected.

关键词： Polymer Sciences   Surfaces and Interfaces   Thin Films  

摘要： Theoretical analysis has been employed to study the effects of electrical conductivity and viscosity of a liquid on its electrodispersion from the edge of a capillary, through which the liquid is supplied to a discharge system. It has been shown that, when a high-conductivity and low-viscosity liquid is dispersed, it emits strongly charged small droplets, which are primordially unstable with respect to their own charges and disintegrate into several hundred still smaller droplets, which are also strongly charged and unstable. A corona discharge is ignited around each droplet and a glow arises, which is referred to as the "fan" glow. When a low-conductivity or a high-viscosity liquid is dispersed, it emits small charged droplets, which are stable with respect to their own charge (in the first case) or strongly charged droplets, which disintegrate into two or three droplets stable with respect to their own charge (in the second case).

关键词： Aloe vera   Chitosan   Dipping treatment  

摘要： Litchi exhibits very limited postharvest life due to rapid softening and decay in spite of being a non-climacteric fruit. After the 3rd day onwards the fruit shows cracking and browning of skin. Litchi fruits after harvesting were dipped with Aloe vera and different safe products like chitosan, corn starch calcium chloride and salicylic acid. A treatment of Aloe vera 50% + Chitosan 2% was able to reduce the PLW of litchi fruits up to eighth day of storage, exhibited minimum shrinkage of the fruits, minimum change in total sugar content and titratable acidity of the fruits during 8th day of storage. Aloe vera 50% + Chitosan 1% successfully reduced the rate of increase in TSS of the fruits even up to 8th day of storage. Least change in vitamin C content during storage was observed in Aloe vera 50% + Chitosan 1% followed by Aloe vera 50% + Chitosan 2%. The same treatment reduced the incidence of fruit cracking, skin browning and decay percentage. No drastic change in organoleptic property was observed during the storage period. Hence the treatment of litchi with Aloe vera and chitosan can enhance non-refrigerated storage life of litchi up to 8 days. © 2021, The National Academy of Sciences, India.