Silva Vieira, Antonio DiogoBattistini, CarolinaBedani, RaquelIsay Saad, Susana Marta...
8页
查看更多>>摘要：This study evaluated the impact of acerola by-product (ABP) on the viability and resistance to in vitro-simulated gastrointestinal (GI) conditions of Lactobacillus acidophilus LA-5 and Bifidobacterium longum BB-46, individually or in co-culture, in a fermented soy beverage (FSB) during 28 days of storage at 4 degrees C. Eight trials of FSB were studied, using a factorial 2(3) design, in which the variables evaluated were Factor 1 (LA5), Factor 2 (BB46), and Factor 3 (ABP). The populations of microorganisms were determined using quantitative Real-Time PCR combined with propidium monoazide (PMA) treatment. Probiotic populations remained above 7.1 log CFU equivalent/mL throughout 28 days in the FSB, and the co-culture (LA5 + BB46) and the addition of ABP did not affect the viability of both probiotic strains (P > 0.05). However, ABP showed a positive effect on the survival of BB46 under in vitro GI conditions. The FSB supplemented with ABP revealed to be a good plant-based vehicle for the probiotics tested, mainly for BB46. Clinical trials are required to confirm the health benefits of the potential synbiotic soy-based product with ABP.
查看更多>>摘要：Solvent free ohmic-assisted esterification (OAE) was investigated as a promising tool for ethyl butyrate (pineapple flavor) synthesis. To this end, Amberlyst 15 dry was used as an ion exchange catalyst to promote the esterification reaction between ethanol and butyric acid. Solubility, electrical conductivity, and heating rate of the reaction mixture as affected by different salt types and concentrations were studied. Then, the OAE operation parameters (i.e., electrical field, catalyst concentration, and mole ratio of ethanol:butyric acid) were optimized. The highest ethyl butyrate yield (63%) was achieved after 90 min in presence of 1% LiCl, 2% Amberlyst 15 dry using field strength of 25 V/cm and an ethanol:butyric acid mole ratio of 1:1. Optimum conditions of OAE were also compared with microwave- and magnetic stirrer-assisted esterification methods. OAE provided the highest yield (61.20%) at a shorter time with the lowest specific energy consumption (0.04 kWh/g ethyl butyrate) and specific CO2 emission (0.03 kg CO2/g ethyl butyrate). The micrographs of scanning electron microscopy showed less structural damages in the catalyst structure using OAE compared to other esterification methods. Therefore, OAE can be proposed as a cost-effective and environmentally friendly technology for the synthesis of flavor esters in the food industry.
Fei, TaoLeyva-Gutierrez, Francisco M. A.Wan, ZifanWang, Tong...
9页
查看更多>>摘要：A novel single pendent hydroxy functionalized soy-wax was synthesized via hydroboration-oxidation of high oleic soybean oil (HBO-HOSO). Low apparent viscosity emulsions containing such wax was formulated as an alternative to the high-cost carnauba wax (CAR) and resin-based emulsions used in citrus fruit coatings, mainly to impart sheen and prevent moisture loss. The effect of additional CAR on properties of HBO-HOSO emulsions was analyzed, and the performance of the optimal formulation for citrus coating was evaluated. Addition of CAR to HBO-HOSO led to an increase in apparent viscosity, although reduced the particle size of the emulsion. An emulsion containing 20% HBO-HOSO of total solid content resulted in a low apparent viscosity and small particle size, comparable to commercial emulsions made from CAR (O-Wax and ORO), oxidized polyethylene (LS-Wax) and shellac resin (STAR). Adherence of coatings made with HBO-HOSO to the fruit surface was not significantly different compared to commercial benchmarks. The HBO-HOSO-containing emulsion provided similar gloss and resulted in reduced moisture loss (6.0%) compared to the commercial products (7.0-14.6%). HBO-HOSO-containing emulsions also did not affect the release of imazalil, a common fungicide applied on citrus fruits, and simultaneously more effectively inhibited the growth of Aspergillus niger (ATCC 16888).
查看更多>>摘要：The application of cold-pressed sesame oil (CSO) in the food industry is limited by its weak oxidative stability. The objective was to improve the oxidative stability of CSO by using different solid acid catalysts (SACs) with heat. The effects of SACs on the physicochemical properties, lignan content, oxidative stability and antioxidant capacity of oil samples were investigated. The different oil samples were: CSO without catalyst or heat (L); CSO without catalyst but with heat (CK); and CSO treated with four different SACs, namely hydrogen beta zeolite (H beta), citric acid (CA), CA loaded on H beta (CA/H beta), 12-tungstophosphoric acid (PA) and PA loaded on H beta (PA/H beta). In the oil samples treated with SACs, the content of sesamin and sesamolin decreased significantly, and the content of asarinin and sesamol increased accordingly. The oxidative stability and antioxidant capacity of the oil samples H beta, CA/H beta and PA/H beta were significantly enhanced (P < 0.05). The characterization of SACs showed that CA and PA were distributed uniformly inside the framework of H beta. In summary, using SACs with heat effectively converted lignan into asarinin and sesamol, and enhanced the oxidative stability of CSO. This information should be useful for exploring the potential industrial applications of CSO.
查看更多>>摘要：Salmonella is a food-borne pathogen that causes worldwide infections in humans and animals. Over 2600 Salmonella serovars have been identified, and serogroup C1 (O:6, 7 epitopes) contains highly diverse serovars associated with high pathogenicity. Here, we aimed to develop a reliable polymerase chain reaction (PCR) method for detecting serovar-specific markers of Salmonella serogroup C1, with greater reliability and lower complexity than current methods. We identified three, two, four, and one novel genes unique to the Infantis, Rissen, Braenderup, and Virchow serovars. The PCR primers targeting these genes were specific for the target serovars. The detection limits of the PCR assays using 9 pairs of primers were 10(2)-10(3) colony-forming units (CFUs)/mL and 10(4)-10(5) CFU/g in pure bacterial cultures and artificially contaminated raw pork samples, respectively. No false-positive or false-negative results were obtained with 45 food samples, as determined by comparison with biochemical tests and traditional serotyping methods. The potential functions of all serovar-specific genes identified are unknown, except for one Rissen-specific gene that encodes a secreted protein. Our results imply that all 10 novel, specific genes can be considered as useful targets for detecting the Salmonella Infantis, Rissen, Braenderup, and Virchow serovars in food.
查看更多>>摘要：In this study, response surface methodology (RSM) based on central composite rotatable design applied to encapsulate glycyrrhizic acid (GA), within the ultrasound-assisted double emulsions. Three independent variables considered as the 10-30% weight of the internal aqueous phase (W-1) in the primary-emulsion (W-1/O), 6-10% of polyglycerol-polyricinoleate (PGPR) as the surfactant in the oil phase, and 4-6 min sonication-time; dependent variables for optimal W-1/O emulsion fabrication were droplet-size, poly-dispersity-index (PDI), and sedimentation-index. Then, 5-25% wt. of the W-1/O emulsion dispersed into the skim milk as an external aqueous phase (W-2) to form double-emulsions (W-1/O/W-2) through sonication for 1-5 min. The lowest dropletsize and sedimentation-index obtained for the W-1/O emulsions formulated by 19% W-1 in the W-1/O emulsion, 6% PGPR and a sonication time of 6 min. Two optimal-conditions for preparation of double-emulsions were determined based on the results of encapsulation efficiency, droplet-size, and viscosity as follows: the first optimum treatment (15% W-1/O and 3 min sonication) and the second optimal conditions (24% W-1/O and 4 min sonication). The encapsulation efficiency of GA in these double-emulsions was 92%. The emulsions stored for 7 days at 37 degrees C showed instability (2-phase separation). In addition, droplet-size and encapsulation-efficiency increased and decreased during storage, respectively.
查看更多>>摘要：This study aimed to investigate the effects of sodium nitrite treatment on antioxidant enzyme activity and free radical changes in yak meat during wet curing. The effect on superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and nitric oxide synthase (iNOS, TNOS) activity; superoxide anion (O-2(-)) content and production rate; hydrogen peroxide (H2O2) content; nitric oxide (NO) content; and meat hydroxyl radical ((OH)-O-center dot) inhibition ability were determined. The results showed that NaNO2 treatment effectively increased the activity of CAT, GSH-Px, and NOS (TNOS, iNOS) over the first 3, 5, and 7 days (P < 0.01) following application, respectively, while simultaneously inhibiting the activity of SOD (P < 0.01). In addition, NaNO2 treatment resulted in an increase in O-2(-) content and rate of O-2(-) production in meat, as well as a decrease (P < 0.01) in H2O2 content on the third day of curing. With the addition of NaNO2, the inhibition ability of (OH)-O-center dot first increased and then decreased, and the NO content in meat increased (P < 0.01). The preliminary study showed that low-dose sodium nitrite could improve the endogenous antioxidant capacity of yak meat during the wet curing process, although it also had negative effects.
查看更多>>摘要：This work investigates the potential of pulsed electric energy (pulsed electric fields (PEF) and high-voltage electrical discharges (HVED)) and high pressure homogenization (HPH) for extraction of bio-molecules from Parachlorealla kessleri. The applied procedures included individual pulsed electric energy (PEF, HVED), HPH treatments, and their combination. The cell concentrations of suspension applied in PEF or HVED treatment were 5-25 g/L, while 5 g/L suspension was always applied for HPH treatment. The effects of applied procedures on the extraction of ionic components, carbohydrates, proteins, and pigments were evaluated. The data evidenced that HVED treatment allowed selective extraction of ionic components and carbohydrates, while HPH treatment was most efficient for simultaneous release all the bio-molecules. HPH treatment (120 MPa, 10 passes) gave 4-fold higher content for pigments, 1.2-fold higher content for carbohydrates and 6.5-fold higher content for proteins than HVED treatment (40 kV/cm, 8 ms). For combined procedure, application of preliminary PEF or HVED treatment with 5 g/L suspension allowed increasing the extraction of carbohydrates at high energy consumption. By contrast, application of preliminary HVED treatment with 15 g/L or 25 g/L suspensions allowed enhancing extraction efficiencies of carbohydrates and proteins, and reducing total energy consumption.
查看更多>>摘要：Fermentation is a key process that affects the quality of black tea. In this study, we discussed the changes and influencing factors of key endoplasmic components at different positions of stacked fermented leaves, and the effects of different preprocessing, variable selection and intelligent algorithm on the model performance are compared, the quantitative prediction model of main endoplasmic components of Congou black tea under different fermentation time series was established, finally, the content distribution is depicted in different colors. The results show that the RPD values of the random forest (RF) prediction model constructed using the optimal variables of theafuscin, thearubigin, catechin, caffeine, and soluble sugar were 3.40, 2.21, 5.71, 1.46, and 2.89, respectively. The RPD values of the support vector machine (SVR) prediction model constructed using the optimal variables of theaflavin and the phenol ammonia ratio were 3.78 and 2.91, respectively. Furthermore, the visualization process successfully displayed the distribution of various quality indicators of the samples at different time periods. These research results lay a theoretical foundation for advancing the judicious processing of black tea.
查看更多>>摘要：The objective of the present work was to develop novel alternative gluten-free premixes for their application in the production of a bread product. Eight formulations of premixes based on light buckwheat flour (LBF) or whole buckwheat flour (WBF) supplemented with chia flour (CF) in a 90:10 ratio (w/w), with and without the addition of xanthan gum (XG 2 g/100 g) were evaluated. A commercial gluten-free premix was used as control. Breads were baked using each formulation and the control premix. The loaves prepared with buckwheat flour and supplemented with CF and XG exhibited a significantly lower mass loss during baking than the control. All the loaves made with LBF presented a higher air fraction, alveolar area and lightness than those prepared with WBF. The joint addition of XG:CF decreased the hardness of the LBF-based loaves. The selected premix (LBF:XG:CF) and the bread exhibited a higher protein, ash, crude fiber and polyunsaturated fatty acid content and antioxidant activity than the commercial premix and its bread (control). The development of premixes based on buckwheat and chia flour represents an alternative with high nutritional value that can be applied to the formulation of gluten-free breads, with adequate technological properties.
NSTL
Elsevier