Hajjari, Mohammad MahdiGolmakani, Mohammad-TaghiSharif, Niloufar
10页
查看更多>>摘要：This work's objective was to develop a novel type of gliadin electrospun fiber with antibacterial properties by incorporating cuminaldehyde in the fibrous structure. Gliadin fibers containing various concentrations of cuminaldehyde were fabricated via an electrospinning process. The morphology and size of the fibers were affected by the concentration of incorporated cuminaldehyde. An optimum value was selected as the highest concentration of cuminaldehyde (20%, w/w). 1H NMR spectroscopy indicated the presence of incorporated cuminaldehyde in gliadin fibers. In addition, the FTIR spectroscopy suggested the occurrence of hydrogen interactions between C--O bonds of cuminaldehyde and N-H bonds of gliadin at 1651 and 3293 cm-1. Confocal Raman spectroscopy and X-ray diffraction revealed a homogenous distribution of cuminaldehyde in the amorphous cuminaldehyde-loaded gliadin fibers with almost no crystalline peaks of cuminaldehyde. Moreover, the gliadin fibers enhanced the thermostability of cuminaldehyde. The hydrophobic cuminaldehyde-loaded gliadin fiber showed a non-Fickian diffusion release, antibacterial activity against Staphylococcus aureus (PTTC 1112) Escherichia coli (PTCC 1399), and is non-toxic to the ASCs. These results confirm the capacity of cuminaldehydeloaded gliadin fibers for being used in food applications.
查看更多>>摘要：Dead-end electro-filtration of polyphenols extracted from apple skin was studied. The influence of membrane pore size (dm = 3.02-50 nm), transmembrane pressure (Delta P = 1-6 bar) and direct current (DC) electric field (U = 5-15 V) on the purification efficiency was investigated. The sieving ratios R of selected membrane UH030 (dm = 4.35 nm) towards the polyphenols, proteins, total solutes, and colour intensity increased with increase of transmembrane pressure. It was demonstrated that utilization of this membrane for the DC electro-filtration allowed more effective rejection of proteins at the anode part of the filter. Such effects can be attributed to the large size of protein molecules and their positive charge. Obtained data evidenced the possibility of selective purification of polyphenols by membrane electro-filtration.
查看更多>>摘要：The present study reports the effect of enzymatic debranching and heating-cooling treatment on morphology, crystallinity and thermal properties of resistant starch preparations from Solanum tuberosum, variety Kufri Bahar. Further, the proliferative and protective effect of resistant starch on viability of probiotic cultures in fermented milk during storage at refrigeration was also investigated. The results indicated that enzymatic treatment resulted in more crystalline form of resistant starch granules with an increased thermal stability. A strain specific prebiotic activity of potato resistant starch was observed with a higher proliferative activity towards Lactobacillus paracasei CD4 among the tested probiotic strains. In synbiotic fermented milk preparation, the supplementation of enzymatic treated resistant starch increased the viability of L. paracasei CD4 under refrigeration up to 14 days as compared to control (p < 0.05).
Moreno, Helena M.Borderias, A. JavierTovar, Clara A.
5页
查看更多>>摘要：Mixed surimi gels with 5 and 8% of pea flour (PF) and 1.41% of pea protein isolate (PPI) were made to replace part of the myofibrillar proteins with legume compounds. Viscoelastic properties in the linear viscoelastic range of fresh mixed gels and control surimi gel were compared with frozen-stored gels for one year. Fresh PPI-surimi gels were more flexible (higher.max), with greater energy stability (higher E parameter) and gel strength (higher G' and G '' moduli) than the control gel. These gel properties were sustained after one year of frozen storage. Fresh mixed PF-surimi gels at 5% and 8% PF concentration were less flexible with lower network-energy, less solid-like character (higher tan delta) and higher gel strength, particularly at 8% PF as compared to the control gel. Frozen storage of PF-surimi gels slightly reduced gamma(max), E, tan delta and percentage of elasticity. Surprisingly, in the control surimi gel, frozen storage improved the energy stability, conformational flexibility, maintaining similar values of gel strength and mechanical elasticity to fresh gel.
查看更多>>摘要：The wine industry routinely employs sulphur dioxide (SO2) as an additive for antiseptic, antioxidasic and antioxidant activities. Some of the most important wine metabolites such as acetaldehyde, diacetyl, pyruvic acid, a-ketoglutaric acid, hydroxymethylfurfural, furfural and acetoin are known to react with SO2 over time to form adducts. H-1 NMR spectroscopy of wine can be tricky as metabolites exist either in original form or as O-adducts or as S-adducts at different SO2 concentrations. We are proposing a methodology for metabolites identification including all the possible SO2 generated species. H-1 NMR spectroscopy is able to highlight the structural changes that a metabolite undergoes in wine in the presence of SO2. The H-1 NMR spectra of the main wine metabolites known to react with SO2 were recorded in wine-model solutions at SO2 concentrations at 0, 50, 100 and 150 mg/L that are all below the maximum level allowed by the European Union regulations. Acetaldehyde was completely transformed into the corresponding hydroxysulfonate at a SO2 concentration of 100 mg/L. The concentration of this metabolite was assayed in ten commercial Moscato wine samples including the H-1 NMR resonances of all its identified forms. The results corresponded to those determined according to the OIV standard protocols.
Rivas, Maria AngelesCasquete, RocioCordoba, Maria de GuiaBenito, Maria Jose...
7页
查看更多>>摘要：The objective of this study was the optimization of supercritical fluid extraction (SFE) using CO2 for extraction of bioactive compounds from pomegranate peel, evaluating the functional properties of different extracts (SFE extracts and alcohol-insoluble residues (AIR)). A Box-Behnken design combined with response surface methodology (RSM) was used to optimize extraction pressure (250-300 bar), temperature (45-55 degrees C) and time (2-4 h). The results showed that these SFE conditions have a significant effect on the responses studied. Antioxidant activities of the extracts, residual dietary fibre and pectin were the parameters that best fitted the quadratic model developed in this study. RSM optimization of these parameters was performed using Derringer's desired function methodology, estimating optimal conditions for extraction pressure (291 bar), temperature (46.5 degrees C) and time (2.5 h). The results reveal that supercritical technology is an interesting option for fractionating and recovering high-value compounds from pomegranate by-products.
查看更多>>摘要：Acid treatment is one of the most effective methods to convert flavonoid glycosides into their aglycones. In this study, the impacts of acid treatment of tartary buckwheat grains on the flavonoid composition and biological activities of tartary were investigated. The results indicated that acid treatment allowed the deglycosylation of rutin to quercetin in buckwheat grains, contributing to the enhancement of their antioxidant activity. Furthermore, as compared to the non-treated sample, acid-treated buckwheat grain samples showed stronger inhibition on tert-butyl hydroperoxide mediated the formation of intracellular reactive oxygen species in HepG2 cells, reduction in lipid accumulation and the related adipogenic transcription factors in 3T3-L1 cells, and reduction in inflammatory mediators in RAW 264.7 cells. Upon application to noodles making, noodles supplemented with acid-treated tartary buckwheat flours, which had weakened gluten strength and a low degree of gelatinization, displayed significantly improved antioxidant activity. These findings suggest that acid-treated buckwheat flours can be used to improve the health benefits of buckwheat products.
查看更多>>摘要：In this study, thermal processes were developed for cocoa powder against Salmonella and Listeria monocytogenes in a pilot Radiofrequency (RF) unit and validated using their respective surrogates Enterococcus faecium NRRL B2354 and Listeria innocua. For 1.0 kg cocoa powder samples, RF heating to 90 degrees C provided 1.74-1.84 log reduction of E. faecium. A 48 min holding post-RF heating provided an additional 3.65 and 2.24 log10 CFU/g reduction of E. faecium for insulated and non-insulated samples, respectively. Compared to E. faecium, L. innocua was less resistant to RF heating in aw 0.45 cocoa powder; RF heating to 75 degrees C coupled with 24 min insulated holding resulted in an additional 5.64 log10 CFU/g reduction. These data suggested that E. faecium was a conservative surrogate strain for controlling Salmonella and L. monocytogenes during RF processing of cocoa powder. To achieve maximal microbial reduction and improve energy efficiency, an insulated holding following RF heating is highly recommended. According to the predictive line obtained from the Bigelow model, a 7.6 min RF heating plus 48 min insulated holding attained a 5-log reduction of E. faecium without a negative impact on the color of cocoa powder.
查看更多>>摘要：Honey is usually adulterated by cheaper, commercially available sugar syrups with similar chemical composition. Adulterated honeys are frequently marked as natural and are valued in the same way as pure honeys and as a result, there is a growing need for rapid, simple, and accurate analytical methods to evaluate their characteristics and authenticity. In this work potential of UV-VIS and NIR spectroscopy coupled with PLS modelling and ANN modelling was analysed for the detection of adulteration and quantification of the physical and chemical proprieties of pure and adulterated honey samples. Acacia honey samples from Krapina-Zagorje County (Croatia) were adulterated by corn syrup (10-90%). The results indicate that PLS models developed in this work, except that for moisture content, can be used efficiently for screening (7<RER<20) ANN modelling provided accurate and simultaneous prediction of the properties of honey with correlation coefficients for validation above 0.8 so that these results show significant performance of ANNs modelling in the prediction of the physical and chemical properties of pure honey samples and adulterations based on combined UV-VIS NIR spectra.
查看更多>>摘要：Drying as an effective food preservation method, extends the shelf-life of the food and reduces storage, packaging, and transportation costs. Each of the common drying methods imposes limitations on the end products' quality and energy efficiency. Novel approaches such as electro-based drying methods have recently emerged to improve the drying process. They can be defined as a drying process in which electrical energy is employed during the pretreatment or during the drying treatment, namely electrohydrodynamic (EHD), pulsed electric field (PEF), ultrasound-assisted, and dielectric drying (microwave and radiofrequency). This review aims to provide an overview regarding the promising common electro-based drying methods used for food and agriculture products. Besides, the mechanism of action and potential applications of electro-based drying methods are discussed. Existing literature data demonstrates that electro-based water removal technologies can enhance drying kinetics without any negative impact on food quality.
NSTL
Elsevier