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ISBN: (纸本)9787122400642

关键词： Acanthophyllum laxiusculum   Saponin   Foam stability   Antioxidation   phenolic compounds  

摘要： Aqueous Extract of Acanthophyllum laxiusculum root (AE) exhibited remarkable foaming profile, emulsification properties and antifungal activity due to the presence of high concentration of total saponins. Total phenolic compounds, another main component, accounted for the AE antioxidant activity. Spray drying of AE, as a thermal process, did not affect the foaming indices of A. laxiusculum Spray-dried Extract (SE) and is a recommended alternate for convenient application in food industry. Addition of SE to the malt extract at accepted levels of total saponin daily intake (below 50 mg/kg) showed positive attribution of malt and carbonation on the foaming quality of SE. Meanwhile, antioxidant activity of commercial malt beverage was enhanced by addition of phenolic compounds containing SE. The 20-60% antifungal inhibitory ratio of the SE developed here is within the applied range of total saponin that supports its application to inhibit the growth of Saccharomyces cerevisiae after malt beverage production. The bitter taste of SE was not sensed in malt beverage at 30 mg/kg total saponin content and suggested A. laxiusculum root extract as a natural additive in malt industry.

关键词： Balangu   Lallemantia peltata   Seed oil   Fatty acids   Cold-press   Tocopherols   Storage  

摘要： The present research studied the oil content of Lallemantia peltata (Balangu) extracted by cold pressing method. Before extraction, the moisture contents of the seeds were adjusted to 0, 2.5, 5, 7.5 and 10 % to evaluate its effect on the oil yield and its quality. Moreover, the physicochemical characteristics were measured during storage for up to 90 days. The optimum moisture content which gave the highest oil yield (33.5 %) was 7.5 %. Increasing of seed moisture content increased acid value, peroxide value and total tocopherols, whereas decreased total chlorophyll and camtenoid as well as oxidative stability. During storage, a significant increase (p < 0.05) was observed in the acid and peroxide values and gamma-tocopherol content, while the alpha-tocopheml, delta-tocopherol, chlorophyll and carotenoid contents decreased. However, fatty acids and phytosterol composition did not significantly change by increasing moisture content and storage. Taken together, this study shows that the moisture content has a crucial influence on the oil yield and the quality of Balangu oil. Also, Balangu oil is rich in n-3 and n-6 acids and its nutritional profile is excellent and would be a good source of edible vegetable oil.

关键词： Hydrostatic pressure   oat starch/beta-glucan mixture   microstructure   physicochemical properties  

摘要： Oats do not contain gluten protein, and oat dough structure is formed mainly through the hydrogen bonding of starch and beta-glucan. As a non-thermal processing technology, high hydrostatic pressure (HHP) is mainly used to modify starch and protein in food processing. This study investigated the effects of HHP treatment on the morphological, structural, thermal, pasting and in vitro digestion properties of oat starch/beta-glucan mixtures. Results showed that beta-glucan interconnects with amylose through hydrogen bonding and has a protective effect on the crystalline region of oat starch. Effect of HHP treatment on the crystal structure of mixture system goes through crystal structure perfection stage, crystallisation disintegration and gelatinisation stage. After 300-400 MPa treatment, the changes in particle surface were not obvious, the phase transition temperature, the Delta H-gel and the PT of mixtures increased, while the particle size, viscosity and BD values decreased. After 500-600 MPa treatment, mixtures were completely gelatinised, most of the particles swelled and deformed, the particle size increased significantly. The principal component analysis results show that the complexes were distributed in the same region with similar properties after the 300-400 MPa and 500-600 MPa treatments, respectively.

关键词： pea protein   physicochemical properties   emulsification   high-pressure homogenization  

摘要： BACKGROUND There is an increasing trend in the food industry to utilize plant-based proteins. Pea protein (PP) is one such protein that is a promising alternative emulsifier. However, there is a significant functionality gap between laboratory and commercially produced PP that limits its usage. The physicochemical and emulsification properties of five commercial PP powders were characterized to better understand the functionality gap. RESULTS Four of the five commercial powders displayed low solubility, high surface hydrophobicity, and an abundance of large insoluble aggregates. High-pressure homogenization was able to break up the aggregates, reduce surface hydrophobicity, and increase solubility. There was a significant correlation between the homogenized solubility and the emulsification properties of the commercial PPs. There was not a significant correlation between the emulsification properties and the other physicochemical properties (unhomogenized solubility, zeta potential, surface hydrophobicity, and interfacial tension). CONCLUSIONS The conformational changes caused by the commercial isolation process may disrupt the correlations between the physicochemical and emulsification properties of PP. Solubility is a key physicochemical property to enable good emulsification properties for PP. Homogenization is an effective step to improve the solubility of commercial PP and therefore promote its functional properties before industrial usage. (c) 2021 Society of Chemical Industry.

关键词： dough   gluten   interactions   rheological   starch   structural property  

摘要： This study mainly explored that the influence of wheat starch source on the rheology behaviours and structural properties of gluten-starch dough, and then the model doughs were prepared by the AK58 wheat gluten and three types of starches from strong (ZM366S), medium (AK58S) and weak gluten wheat (ZM103S) during mixing were studied. The damaged starch content of wheat starch was positively correlated with the wheat gluten strength, while the granule size was negatively. The G', G" and the extension resistance of ZM366S dough were higher than those of other doughs, which implied the source of starch also had a significant influence on the rheological properties. CLSM also observed that ZM366S was more closely bound to the gluten protein network. The glutenin macropolymer (GMP) content of ZM366S model dough was the highest, while the SH content was the lowest. Decreases in elasticity, extension and GMP, and small increase in SH content were displayed during dough mixing. Molecular forces were varied with different wheat starch and mixing time. The covalent bond was the main force between ZM103S and gluten, whereas the hydrogen and covalent bonds were the main force between ZM366S or AK58S and gluten. The interactions between ZM366 starch and gluten were stronger than others starch.

关键词： Ananas comosus   Enzymatic hydrolysis   Agro-industrial waste   Viscosity   Particle size  

摘要： The pineapple (Ananas comosus) is an important tropical fruit in the world market. Its pulp has significant nutritional value while the peel and the core, in spite of being high in dietary fibre and nutrients, are generally considered to be agro-industrial waste. The aim of this research was to evaluate the effect that the integrated enzymatic and shear homogenization processes have on the physicochemical stability of pineapple base suspensions (pulp, core, and peel extract). Initially, an enzymatic hydrolysis process was evaluated with a completely randomized factorial design. Independent variables: incubation time (t(inc)) (1-4 h) and [enzyme] (0-200 ppm). Dependent variables: viscosity (mu) and particle sizes (D-[3;2] and D-[4;3]). The results showed a reduction of (mu) (70.7%), D-[3;2] (54.2%), and D-[4;3] (61.8%) for the optimized treatment (t(inc) = 3.2 h and [enzyme] = 200 ppm) compared to the control (t = 0, without enzyme). The effect of the integrated enzymatic treatment with a serial homogenization process was subsequently evaluated. Independent variables: high-speed homogenization time (t(1)) (15-20 min), recirculation time in high pressure homogenizer (t(2)) (3-7 min), and arabic gum (AG) (0.6-1.0%). Dependent variables: total suspension solids (TSS), zeta potential (zeta), mu, spectral stability index (R), D-[3;2], and D-[4;3]. The application of the integrated processes of enzymatic treatment and serial homogenization was more effective to be able to obtain a stable pineapple-based suspension. The experimental optimization of multiple responses defined t(1) = 16.4 min, t(2) = 7 min, AG = 0.98%, and TSs = 15.7 +/- 0.5%, zeta = - 23.1 +/- 0.4 mV, mu = 221 +/- 11 cP, D-[3;2] = 56.8 +/- 2 mu m and D-[4;3] = 120.6 +/- 4 mu m and R = 0.58 +/- 0.02 were obtained.

关键词： Eggplant   lipid oxidation   low-fat patties   protein deteriorations  

摘要： Effects of different drying methods and different addition levels of eggplant (EP) on product quality of low-fat patties (LFPs) were investigated during storage. EP was dried in an oven dryer at 60 degrees C or a freeze dryer at -50 degrees C. LFPs were prepared by replacing with 1.5% soy protein isolate (SPI). Six treatments were used in this study: (1) control (CTL), without addition of EP;(2) reference (REF), 0.1% ascorbic acid;(3) O1, 0.25% oven-dried (OD) EP;(4) O2, 0.5% ODEP;(5) F1, 0.25% freeze-dried (FD) EP;and (6) F2, 0.5% FDEP. Redness (a*) and lightness (L*) values in LFPs added with EP were lower than those of others (p < 0.05) and decreased with increasing storage time. Yellowness (b*) values of cooked patties were increased during storage time (p < 0.05), with control having the highest value. The addition of EP or ascorbic acid into LFPs lowered microbial counts than control (p < 0.05). Thiobarbituric acid reactive substances (TBARS) was increased during storage, with REF having the lowest value, and patties added with EP had lower TBARS values than control during storage. Volatile basic nitrogen (VBN, mg%) contents of all patties also increased during storage time with O2 and F2 having lower values than control. Therefore, EP might have potential as a natural antioxidant in meat products during storage.

关键词： Sous vide   Zingibain   Protease   Shelf life   Quality   Storage  

摘要： The aim of the study was to investigate quality and shelf life of beef meat cooked under sous vide conditions then extended refrigerated storage for 10 weeks. Biceps femoris (n = 6) from six to seven year old cows were treated with 2 g/L ginger powder (GP) containing zingibain or control (no injection) and were then cooked in sous vide conditions at 65 degrees C for 1 h or 8 h. Cooked samples were evaluated for physicochemical (pH, total water content, cooking loss, Warner-Bratzler shear force (WBSF), texture profile analysis (TPA), L*, a*, b* properties and thiobarbituric acid reactive substance (TBARS)), microstructure (scanning electron microscopy) and microbiological (Brochothrix thermospacta, Clostridium perfringens, Lactic acid bacteria, Listeria monocytogenes, Salmonella spp, and yeasts and moulds) quality after vacuum packing, cooking, then refrigerated storage at 4 degrees C for 0, 2, 4, 8 or 10 weeks. Physicochemical parameters were improved by GP treatment (P < 0.05) while there was no effect of storage time on WBSF, TPA or microstructure. The microbial quality of sous vide cooked meat in refrigerated storage appeared to be four weeks and oxidation shelf life of the cooked meat was found to be two weeks under refrigerated storage.

关键词： Physical Chemistry   Electrochemistry   Energy Storage   Characterization and Evaluation of Materials   Analytical Chemistry   Condensed Matter Physics  

摘要： Ti1-xFexO2-delta nanoparticles (NPs) with varying content of Fe (III) ions (x = 0.008 to 0.024 and delta =0.5x) were synthesized using sol-gel method at room temperature, and thereafter these NPs have been connected to CdS quantum dots followed by sensitization with N719 moieties for photovoltaic measurements. After the characterization, the powder form of Ti1-xFexO2-delta was mixed thoroughly with DMF solvent followed by CH3CN solvent using ultrasonicator, and then the binder-free paste was coated on transparent conductive oxide F:SnO2 (FTO) glass substrate using doctor blade technique to obtain uniform photoelectrode. After calcination, these different photoelectrodes were subsequently sensitized with either CdS QDs or N719 dye or both. Moreover, the photovoltaic performance of these prepared photoanodes was studied for the different compositions of Ti1-xFexO2-delta when it co-sensitized with CdS QDs and N719 dye. The solar device were designed through Ru-based N719 dye anchored onto Ti1-xFexO2-delta-CdS QDs photoanodes and counter electrode (Pt) as well as electrolyte (I-/I-3(-)) and tested using solar simulator under standard light condition (100 mW/cm(2)). The overall conversion efficiency of DSSCs is 3.48% for Ti0.992Fe0.008O1.996:CdS:N719 dye;which is 1.5 times more than undoped TiO2 NPs.