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关键词： Highland barley bran   beta-Glucan   Physicochemical properties  

摘要： Highland barley grains were roller-milled to produce five different fractions (B-1, B-2, B-3, B-4, and B-5). The distribution and physicochemical properties of beta-glucans from five roller-milled fractions were investigated. The B-4 fraction contained the highest concentration of beta-glucan (4.40%), and the outermost bran (B-1) had the lowest beta-glucan content (1.01%). Besides, beta-glucans from inner core B-5 (BG-5) had higher M-w (6.482 x 10(5) g/mol), whereas beta-glucans from outer bran B-1 (BG-1) showed lower M-w (5.859 x 10(4) g/mol) than those from other fractions. Accordingly, the viscosity of BG-5 was highest (0.038-0.365 Pa.s), and the water solubility index of BG-1 was highest (50.43-90.71%). BG-5 showed stronger foam stability and emulsifying properties but weaker foaming capability, while BG-1 exhibited stronger foaming capability. The foaming capability and emulsifying properties of beta-glucan samples were better under the neutral condition (pH = 7). The foam capabilities of all beta-glucan samples displayed higher values at 65 degrees C, and emulsifying properties exhibited higher values at 45 degrees C. This study is expected to promote the application of highland barley beta-glucans in food industry.

关键词： Collagen hydrogels   Modification   Epigallocatechin gallate   Physicochemical property   Molecular docking  

摘要： Collagen Type I derived from fish is mainly limited by its poor physicochemical properties for further applications. In this study, we developed epigallocatechin gallate (EGCG) cross-linked collagen hydrogels (EC hydrogels) to realize physicochemical improvements, basing on the interaction mechanism between collagen and EGCG. The integrity of collagen framework with slight secondary structure change in the presence of EGCG was confirmed. The stronger stability of collagen fibrils was proved by slower swelling ratio, declined enzymatic degradation, improved thermal analysis and mechanical test due to EGCG modification. To illustrate the potential mechanism between collagen and EGCG, molecular docking was used to identify both covalent (C-N bond, between lysine of collagen and C2-ring B of EGCG) and non-covalent bonds (hydrogen bond and hydrophobic interaction) within in EC hydrogel. Taken together, this work would offer some insights into the further study about the interaction between EGCG and collagen.

关键词： Sodium reduction   Time-intensity   Sodium dissolution kinetics   Particle adhesion   Foam-mat processing  

摘要： Novel sodium reduction strategies are urgently required by the food industry. We hypothesised that redesigning salt crystals (size, density, hydrophobicity and flow properties) will offer a new route to increase saltiness and therefore reduce sodium. Eight salts were compared with different physicochemical properties, the resultant particles were characterised and adhesion to product, loss in-pack, rate of dissolution and ultimately saltiness perception were evaluated. Principle findings included that particle adhesion was driven by particle size (r = -0.85, p = 0.008), bulk density (r = -0.80, p = 0.017) and flow properties (r = 0.77, p = 0.015);loss in-pack was associated with particle size and hydrophobicity of the salt particle while dissolution and/or saltiness perception was also driven by particle size and hydrophobicity of the salt particle. The findings offer a new set of design rules for future ingredient design for the food and flavour industries.

关键词： Ultrasound   Heat-moisture   Molecular structure   Physicochemical properties   Digestion properties   Pea starch  

摘要： Ultrasound is increasingly used for physicochemical modification of food systems as a green technology. Effects of heat-moisture treatment (HMT) assisted by pre- and post-treatment of ultrasound on physicochemical, structural and digestive properties of pea starch was investigated. Pea starch maintained the original morphology and C-type of crystalline after ultrasound treatment (UT), but 4 h or more of HMT and HMT assisted by UT changed the crystalline from C-type to A-type. All treatments decreased the crystallinity, molecular weight, swelling power and solubility at 70-90 degrees C, and elevated the content of resistant starch. Moreover, HMT assisted by pretreatment of UT was found to increase the viscosity and high-temperature stability of starch paste compared with others by the orderly combined effect of UT-induced depolymerization and HMT-induced depolymerization and rearrangement of starch chains. These results may promote the appropriate use of ultrasound in food industries and the production of starch materials for potential applications.

关键词： Hydrogen bonds  

摘要： Physical aging in colloidal dispersions manifests as a reduction in kinetic freedom of the colloids. In aqueous dispersions of charged clay colloids, the role of interparticle electrostatic interactions in determining the aging dynamics has been evaluated extensively. Despite water being the dispersion medium, the influence of water structure on the physicochemical properties of aging clay dispersions has, however, not been considered before. In this work, we use LAPONITE (R), a model hectorite clay mineral that acquires surface charges when dispersed in water, to study the relative contributions of dispersion medium structure and interparticle electrostatic interactions on the physicochemical properties of aging hectorite clay dispersions. The structure of the dispersion medium is modified either by incorporating dissociating/non-dissociating kosmotropic (structure-inducing) or chaotropic (structure-disrupting) molecules or by changing dispersion temperature. Photon correlation spectroscopy, rheological measurements and particle-scale imaging are employed to evaluate the physicochemical properties of the dispersions. Our experiments involving incorporation of external additives demonstrate a strong influence of dispersion medium structure on the dispersion properties when the interparticle electrostatic interactions are weak. We introduce a new temperature dependent measurement protocol, wherein the temperature of the medium is fixed before adding the clay particles, to manipulate the hydrogen bonds in the aqueous medium in the absence of external additives. Accelerated aging, observed upon raising the temperature regardless of the experimental thermal histories, is attributed to increased interparticle electrostatic interactions as in the room temperature experiments with ionic additives. Our study identifies that in the presence of weak interparticle electrostatic interactions, changes in the physicochemical properties of charged clay dispersions can be driven by

关键词： electrocatalysis   amorphous carbon   x-ray spectroscopy   density functional theory   machine learning  

摘要： Connecting a material's surface chemistry with its electrocatalytic performance is one of the major questions in analytical electrochemistry. This is especially important in many sensor applications where analytes from complex media need to be measured. Unfortunately, today this connection is still largely missing except perhaps for the most simple ideal model systems. Here we present an approach that can be used to obtain insights about this missing connection and apply it to the case of carbon nanomaterials. In this paper we show that by combining advanced computational techniques augmented by machine learning methods with x-ray absorption spectroscopy (XAS) and electrochemical measurements, it is possible to obtain a deeper understanding of the correlation between local surface chemistry and electrochemical performance. As a test case we show how by computationally assessing the growth of amorphous carbon (a-C) thin films at the atomic level, we can create computational structural motifs that may in turn be used to deconvolute the XAS data from the real samples resulting in local chemical information. Then, by carrying out electrochemical measurements on the same samples from which x-ray spectra were measured and that were further characterized computationally, it is possible to gain insight into the interplay between the local surface chemistry and electrochemical performance. To demonstrate this methodology, we proceed as follows: after assessing the basic electrochemical properties of a-C films, we investigate the effect of short HNO3 treatment on the sensitivity of these electrodes towards an inner sphere redox probe dopamine to gain knowledge about the influence of altered surface chemistry to observed electrochemical performance. These results pave the way towards a more general assessment of electrocatalysis in different systems and provide the first steps towards data driven tailoring of electrode surfaces to gain optimal performance in a given applicatio

关键词： Musa balbisiana   Wild banana   Pulp   Powder   Spray   Oven   Freeze drying   Nutritional   Physicochemical  

摘要： Purpose The study was aimed to compare the effect of three drying techniques viz., spray, freeze and hot air oven (HAO) drying on yield, nutritional parameters, minerals and physicochemical and morphological characterization of wild banana pulp (Musa balbisiana Colla). Design/methodology/approach Contents of carbohydrate was estimated by Anthrone reagent, protein by Kjeldahl, fat by Soxhlet, dietary fiber and ash by Association of Official Analytical Chemists (AOAC), minerals by Atomic Absorption Spectrophotometry, gross calorific value by Bomb calorimeter, moisture by moisture analyzer, water activity by water activity meter, morphological characterization by Scanning Electron Microscopy (SEM), statistical level of significance at p < 0.05 by ANOVA, predictive modeling by simple and multiple linear regression. Findings Freeze and HAO drying were standardized with matured (stage 2) and spray drying with ripe bananas (stage 6). Freeze drying showed highest yield (76.69 +/- 0.15%), minerals viz., K (1175.67 +/- 1.41), Fe (2.27 +/- 0.09), Mg (120.33 +/- 0.47), Mn (4.40 +/- 0.28) mg/100 g, protein (7.53 +/- 0.14%), lesser moisture (7.95 +/- 0.01%), water activity (0.17 +/- 0.02a(w)), hygroscopicity (6.37 +/- 1.09%), well dispersed particles by SEM. HAO drying exhibited highest dietary fiber (18.95 +/- 0.24%), gross calorific value 357.17 kcal/100 gm, higher solubility (47.22 +/- 0.86%). Spray drying showed highest carbohydrate (85.29 +/- 0.01%), lowest yield (28.26 +/- 0.32%), required 30.5% adjuncts. Research limitations/implications Effect of three drying techniques and use of adjuncts were not uniform for ripe and matured bananas. Practical implications Commercial utilization of seeded wild banana. Social implications Value addition of wild banana in Assam, India Originality/value Freeze drying of mature wild banana pulp (M. balbisiana) was found as best technique utilizing lesser energy.

关键词： Apricot   Wheat flour   Cookies   beta-carotene   Antioxidants  

摘要： PurposeThe demand for functional foods has been increasing tremendously throughout the globe and keeping in view the health beneficial properties of apricot fruit. The purpose of this study is to develop wheat flour based cookies enriched with apricot pulp powder in order to improve nutraceutical properties of cookies and dilution of gluten at the same ***/methodology/approachCookies were prepared from wheat flour blended with apricot pulp powder at 0, 10, 15, 20 and 25% level and evaluated for proximate, functional, rheological, nutraceutical and sensory *** content of apricot powder-incorporated cookies (3.23%) was significantly (p < 0.05) higher at 25% level than control (1.64%). The water absorption and oil absorption capacities decreased significantly (p < 0.05) upon increasing level of apricot pulp powder. The ss -carotene content, antioxidant activity and total phenolic content increased significantly (p < 0.05) upon incorporation of apricot pulp powder. The thickness of cookies increased, however, diameter and spread ratio decreased with increase in the levels of apricot pulp powder. Lightness (L*) value decreased, while redness (a*) and yellowness (b*) increased when incorporated with apricot pulp powder. Cookies having 25% apricot pulp powder showed maximum hardness and overall ***/valueTo the best of our knowledge, the scientific literature on incorporation of apricot pulp powder in bakery products is scanty. As such the present research has a tremendous scope for the food industries to produce functional bakery products with antioxidant properties and diluted the gluten content at the same time.

关键词： Honey quality   Honeybees   Apis mellifera   Beekeeping   Honey  

摘要： Purpose The purpose of this study is to assess the quality of honey from different agro-climatic zones of Himachal Pradesh in terms of physicochemical characteristics and mineral status. Design/methodology/approach Three honey-producing locations were selected within each agro-climatic zone, honey sampled from four separate apiaries within each location and analyzed for physicochemical characteristics and mineral status using standard methodologies. The data were analyzed using one-way analysis of variance with one-way classification, after appropriate transformation through online OP-STAT software and MS Excel. The correlation coefficient (r) was also calculated. Principal component analysis was done using XL-STAT software. Findings The honey of Zone 4 had highest fructose (36.62%), F:G ratio (1.55), acidity (46.07 meq/kg), vitamin C (25.04 mg/100 g) and diastase (19.22 DN), whereas the pollen density (76,666.67 pollen grains per 10 g), pH (5.94), sucrose (6.94%), hydroxy methyl furfuraldehyde (70.20 mg/kg), amino acid (103.83 mg/100 g), phenols (77.39 mg/100 g), Ca (81.04 mg/kg) and K (354.17 mg/kg) were highest for Zone 2. Highest electrical conductivity (0.24 mS/cm), moisture (16.50 %), glucose (34.20%) and P content (62.93 mg/kg) were recorded for Zone 1. Correlation studies indicated a significant positive correlation between pH and EC;EC and moisture;colour and pollen density. Examining the graphical distribution of the honey samples, a natural separation between honeys of four different agro-climatic zones was obtained. Originality/value The impact of geographical/agro-climatic variations in physicochemical characteristics of honey has not been worked out under the present scenario in Himachal Pradesh.

关键词： Polysaccharides  

摘要： Ganoderma lucidum polysaccharides (GLP) possess remarkable bioactivity and have been studied widely. However, the application of new technologies in the polysaccharide extraction has not been investigated. Herein, a novel continuous phase transition extraction (CPTE) technology was applied for the extraction of polysaccharides from Ganoderma lucidum. The extraction kinetics, physicochemical properties and immunomodulatory activity of GLP were evaluated. The kinetics results showed that the extraction process could be fitted to a two-site kinetic model due to the high R-2 values in the range of 0.9939-0.9999. Polysaccharides extracted by different technologies showed that GLP yield by CPTE could be significantly improved, which was 3.34 times and 2.68 times that of hot water and ultrasonic-assisted extraction, respectively. Molecular weight distribution analysis indicated that high molecular mass polysaccharide proportion by CPTE was the highest among the three extraction methods, which was 2.03 times and 3.41 times as much as that of the hot water and ultrasonic-assisted extraction. Morphology analysis showed that CPTE treatment caused disruption of most of the cells and effective release of intracellular components, implying that CPTE was beneficial to extract polysaccharides. Furthermore, the immunomodulatory assays demonstrated that GLP significantly enhanced the proliferation and production of NO, TNF-alpha and IL-6 in macrophages. Therefore, CPTE was more effective for extracting polysaccharides from Ganoderma lucidum than the common extraction.