Shahin, KhashayarZhang, LiliDelfan, Abbas SoleimaniKomijani, Majid...
9页
查看更多>>摘要：Shigella, the globally distributed causative agent of bacillary dysentery, is an important microbial contamination in raw and ready-to-eat foods. The recent commercial use of phage cocktails in the food industry is evidence that the method is a highly effective solution in controlling the pathogenic bacteria, especially the antibiotic-resistant strains. This research addresses the effects of a novel phage cocktail made of six different lytic bacteriophages to prevent drug resistant isolates of Shigella species in a wide variety of food products with a different matrix structure, viscosity, carbon content, and texture properties including cooked chicken, cherry tomato, yoghurt, cucumber and Chinese cabbage. After seven days of treatment with the phage cocktail, more than 99% of the bacterial count decreased compared to the control sample (P < 0.0001). The cocktail stability in dry conditions showed that the bacteriophages remain desirably active during food products' average shelf life. The prepared phage cocktail showed to be a very effective product for bio-controlling Shigella due to its high overlap of the host spectrums, the potential for use in a variety of foods, and stability in dry conditions.
查看更多>>摘要：beta-glucosidase is widely used in food industry for its glycosidic hydrolysis properties. In this paper, performance of a novel beta-glucosidase BGL0224 from Oenococcus oeni for aroma enhancement of Cabernet Sauvignon wines was explored for the first time. The main projects included electronic nose, gas chromatography-mass spectrometry and sensory analysis. Principal component analysis indicated that electronic nose had the ability to discriminate different treatments by responding specifically to volatile compounds. Adding BGL0224 before alcoholic fermentation significantly increased the "aromatic index" of Cabernet Sauvignon wines. Compared with the control group, adding BGL0224 increased more than 15 volatile aroma compounds of Cabernet Sauvignon wines. Furthermore, with the addition of BGL0224 before alcoholic fermentation, the concentrations of medium-chain fatty acid ethyl esters, long-chain fatty acid ethyl esters and terpenes in wines were 3004.19 +/- 36.14 mu g/L, 4090.37 +/- 94.07 mu g/L and 210.21 +/- 8.98 mu g/L respectively, which were all significantly higher than other treatments. Sensory analysis showed that BGL0224 increased "tropical fruity", "sweet fruity" and "floral notes" characteristics while inhibited "citrus" characteristics of Cabernet Sauvignon wines. Overall, this study provided support for industrial application of BGL0224 by evaluating its performance for aroma enhancement of Cabernet Sauvignon wines.
Ren, ZifeiYu, XiaojieYagoub, Abu ElGasim A.Fakayode, Olugbenga Abiola...
11页
查看更多>>摘要：The combinative effects of both longitudinal cut (Lc) and transverse cut (Tc), and hot air, vacuum, freeze and catalytic infrared drying (HD, VD, FD and CID) techniques on the physicochemical properties of dried ginger was studied. The physicochemical properties determined were shrinkage, hardness, rehydration rate, color, gingerol content, total phenols and flavonoids contents (TPC and TFC), antioxidant activity and volatile components. Results showed that the Lc reduced the drying time significantly, by 15.12-29.6%, compared with Tc; and improved the physical properties (degree of shrinkage, hardness, rehydration rate) of the dried ginger. However, there was no significant difference between them on the chemical properties of the dried ginger. Among the four drying techniques, CID showed the shortest drying time (1.42-1.84 h) and retained the bioactive ingredients (gingerol content, TPC, TFC, and volatile components) better in the dried products. Overall, the study established that Lc treatment combined with CID had an excellent effect on the quality of dried ginger slices and the overall drying efficiency; and thus, were selected as the optimum treatment and drying method for drying ginger.
查看更多>>摘要：Zein is one of the seed storage proteins found in the endosperm of maize. It is soluble in aqueous ethanol solutions with high ethanol content, and forms aggregates when the ethanol content of the solution is lowered. This unique structural variation has long been utilized to prepare nanoparticles that carry hydrophobic drugs. In this research, the optimal conditions for the encapsulation of menthol, the major component of peppermint oil, into zein nanocapsules were investigated. The major controlling factors that govern the encapsulation efficiency of the procedure include ethanol content of the solvent used for the dissolution of zein, concentration of menthol in the solvent, the mass ratio of menthol/zein, and ethanol content of the product solution. This research reveals how the highest encapsulation efficiency can be achieved by producing nanocapsules at optimal conditions. This research also indicates that the procedure for finding optimal conditions for the encapsulation of menthol can also be applied to the case of many other chemical compounds by making use of the phase diagram for solute/ ethanol/water.
查看更多>>摘要：To improve the qualities of corn gluten meal, lactic acid bacteria (LAB) and acid protease were used for solid state fermentation and wheat bran was used as a carbon source supplement, and the nutritional value, antioxidant capacity and bioavailability were evaluated. The results showed that the contents of crude protein, ash, small peptide, free amino acids, total phenol and lactic acid in corn gluten-wheat bran mixture (CWM) significantly increased after fermentation, whereas the neutral detergent fiber, acid detergent fiber and starch contents in fermented CWM (FCWM) were lower than in CWM (P < 0.05). Fermentation process significantly (P < 0.05) increased the reducing power and the DPPH, hydroxyl and superoxide anion radical scavenging capacity of CWM. Furthermore, FCWM also showed the ability to improve the growth performance and relieve weaning stress of calves. Overall, fermentation with LAB and acid protease improved nutritional value, antioxidant capacity and bioavailability of CWM, which provided a feasible solution for the application of corn gluten meal in animal feed.
Ji, Xiao-GuoChang, Kun-LinChen, MaiZhu, Liang-Liang...
11页
查看更多>>摘要：Chitooligosaccharides (COS), with a specific degree of polymerization, were evaluated for their effect on human fecal microbiota, as well as their metabolite, using an in vitro anaerobic batch fermentation model. COS increased the richness and diversity of the gut microbial community. More importantly, the microbial community structure of the COS groups was significantly different from the control and fructooligosaccharides (FOS) groups. COS specifically enriched the butyric and propionic acid-producing microbiota and targeted Faecalibacterium, Clostridium_sensu_stricto_1, C._sensu_stricto_13, and Fusicatenibacter. Furthermore, COS increased the acetic, propionic, and butyric acid contents. The production of propionic acid was greater than that obtained using FOS. Metabolome analysis suggested that COS could upregulate allocholic acid, 1,3-butanediol, 3,4-dihydroxybutanotic acid, and 2-hydroxybutyric acid production and downregulate putrescine, ethanamine, hexanoic acid, and branched chain amino acid (L-valine and L-leucine) production in the fermentation broth. These differential metabolites were closely related to lipid, glucose, and amino acid metabolism. These results should inform further development of COS as potential raw materials for functional foods and health products.
查看更多>>摘要：The effects of oxidation-reduction (redox) potential (E-h) on microbiological and sensory characteristics, volatile compounds, and organic acids of kefir produced using wild or commercial culture were investigated during 21 d of storage. The E-h of the milk was modified using reducing or oxidizing chemical agents. E-h7 (E-h expresses at pH 7) values of control, reduced and oxidized kefirs produced using the wild kefir culture were -195.5, -206.1 and + 178.3 mV, while control, reduced and oxidized kefirs produced using the commercial kefir culture had E-h7 values of -199.6, -208.1 and + 180.7 mV, respectively, on 1 d of storage. Generally, the viability of microorganisms in the kefirs was adversely affected by oxidized conditions, but it was species- and strain-dependent. The E-h caused the change of metabolic routes of the microorganisms and, thereby, the change of volatile compounds and organic acids contents of kefir. Principal component analysis (PCA) of the volatile compounds separated the kefirs according to the culture and redox status. Kefirs with low E-h were characterized by the presence of sulphur compounds, whereas kefirs with oxidative E-h were characterized mainly by aldehydes and diacetyl. In addition, reduced E-h caused arising in sensory preference of the kefir samples.
查看更多>>摘要：Stevia sweeteners-sugar are low-caloric prebiotic components that fermented by beneficial bacteria and enhance the host health. This study aimed to characterize, select the prebiotic for the chosen probiotics to create synbiotic preparation, and investigate their bioactive properties. The structure of stevia sweeteners-sugar was studied by nuclear magnetic resonance (NMR), mass spectroscopy (MS), and Fourier-transform infrared spectroscopy (FTIR). There were possible hexose sugars attached to the aglycon groups. Fermentability of these sweeteners by six Lactobacillus spp. and two Bifidobacterium spp. strains was examined and the pH reduction was comparable to the De Man, Rogosa and Sharpe (MRS) media. The best stevia sweeteners-sugar concentration was 0.5% that had favorable effect on the probiotic growth. Moreover, the added sweeteners to the culture media had clearly better growth of probiotics when compared with inulin. The synbiotic supernatants enhanced the antimicrobial and antibiofilm activities of probiotics against potential pathogens and also supported the antioxidant activity. Short-chain fatty acids (SCFA) determined by HPLC indicated that stevia extract-sugar (SE-sugar) was the best from synbiotic samples. In conclusion, the synbiotic of Lactobacillus casei with SE-sugar as a prebiotic new compound suggested its potential use as pharmaceutical, functional food industry and biocontrol agents for treating bacterial infections.
查看更多>>摘要：A deep understanding upon the relation between anthocyanin extraction performance and physicochemical properties of natural deep eutectic solvents (NADESs) was obtained, and a high-efficiency NADES (Choline chloride-Oxalic acid (ChOa)) was selected and coupled with pulse-ultrasonication for anthocyanin extraction from blueberry pomace. Response surface methodology was adopted to analyzed the significant factors' influence, interactive effects on extraction yield and optimize the extraction conditions. The theoretical optimal conditions with highest yield of total anthocyanins content (TAC) were 3.2 min of ultrasonic time, 325 W of ultrasonic power, 349.15 K of temperature, 60 mL/g of solvent to solid ratio, under which the experimental TAC value (24.27 +/- 0.05 mg C3GE/g DW) was highly correlated with theoretical result (24.28 mg C3GE/g DW). Multi-stability protective effect of ChOa on anthocyanin over acidified ethanol was revealed by stability assays in high temperature, varying pH and light exposure conditions. FT-IR and DSC analysis further characterized the influence of ChOa over acidic ethanol on typical anthocyanins functional groups and thermal behavior of anthocyanin extracts. UPLC-Triple-TOF/MS analysis identified 10 anthocyanins that mainly consisted of delphinidin, petunidin, and malvidin compounds. Overall, this study provided a green, high-efficiency and multistability protective strategy for the recovery of anthocyanins from plant source by-products.
NSTL
Elsevier