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关键词： Gelatin   CMC   SEM   WVP   Mechanical properties   Potassium salts of iso-α   -acids br  

摘要： Edible films based on gelatin/carboxymethyl cellulose (GEL/CMC) blends (100/0, 75/25, 50/50, 25/75, and 0/ 100) incorporated with increasing concentrations (0, 15, 30, 60 mg/100g) of potassium salts of iso-alpha-acids (KIAA) were prepared and characterized. Mixing of GEL with CMC at 50/50 and 25/75 ratios yielded films with phase-separated microparticles. Incorporation of KIAA into the CMC100 carrier resulted in rough and opaque films. The films became more amorphous with the increasing concentration of CMC. Consequently, the higher polysaccharide content was accompanied by lower tensile strength (TS) and elastic modulus (EM). All films with the high concentration of KIAA (60 mg/100g) displayed reduced TS and EM. The control GEL-rich films exhibited significantly lower water vapor permeability (WVP) than the films with the mediumand high-levels of CMC. The KIAA-protein interactions were most likely responsible for the slight decrease in the WVP value of the GEL100 film. In general, an increase in the KIAA concentration resulted in darker yellow-green films with reduced UV/Vis transparency. As expected, the KIAA content in the films decreased over time. Probably due to the high pH, the CMC-rich films exhibited the best ability to stabilize KIAA. The CMC100 films exhibited over 10-fold weaker antiradical potential than the GEL100 films. The highest concentration of KIAA (60 mg/100g) was not an effective dose to cause a significant improvement in the antioxidant potential of all films. The antioxidant activity of the films decreased during storage.

关键词： Primorskii krai   gold-ilmenite placers   titanium   gold   high-tech metals   pyrohydrometallurgy   ammonium sulfate   thiourea-thiocyanate solutions  

摘要： Foundations of technology for multicomponent recovery of useful components from titanium-bearing placers of the Ariadnenskoe deposit by pyrohydrometallurgical methods were investigated. Ammonium sulfate and thiourea-thiocyanate leaching solutions were successfully used to isolate titanium dioxide, gold, and a wide range of associated high-tech metals from the concentrate material. The experience gained in deep processing of gold-ilmenite mineral raw materials will help to more reasonably outline the ways to develop the Far East complex deposits in compliance with the principles of rational nature management and environmental protection.

关键词： Potato starch   Extraction methods   Functional properties   Pasting properties  

摘要： The potato starch extracted by physical, chemical, and enzymatic methods were analyzed for physicochemical, morphological, functional, and pasting properties. In the physical extraction methods, T-1 (water at 30 degrees C) was found better in starch yield, water absorption capacity (WAC), and whiteness. In the chemical extraction methods, starch from T-5 (NaOH-0.25%) had higher WAC, and lower ash content. The starch from T-7 (SDS-ME-2%) had higher amylose, starch purity, and lower amylopectin, moisture, fat content. The starch from T-11 (NaOCl-5.25%) had higher starch whiteness value. In the enzymatic extraction methods, starch from T-13 (cellulase-0.15%) had higher starch yield. Further, the physical (T-1), chemical (T-5, T-7 and T-11) and enzymatic (T-13) methods were used in combination and had shown the better physicochemical and morphological characteristics of starch. The starch from combined method (T-14) had significantly higher yield (12.4%), WAC (259%), swelling power (40.3%), solubility (23.6%), purity (87.3%), and whiteness (95.2%). The starch from combined method also had significantly lower phosphorus (81.7%), protein (0.30%), fat (0.29%), ash (0.26%), crude fiber (0.15%) content, and syneresis (18.8%). The starch from combined method had resulted in the better starch granule structure, pasting properties than most of the other treatments. So, the physical, chemical, and enzymatic treatments in combination can be used for extraction of high-quality starch from potato.

关键词： Brazilian semi-arid   Green manure   Sandy soil   Soil fertility   Leguminous plant species   Tropical ecosystem  

摘要： Purpose Soil physico-chemical properties, biomass production, and root density are considered key factors indicating soil health in an agroecosystem. The soil physico-chemical changes and plant growth (e.g., shoot biomass production and root density) in a 6-year cultivation of plant species used as green manure in a sandy soil from Tropical ecosystem, North-eastern Brazil, were investigated between July and December 2019. Material and methods We characterized soil physical and chemical properties, shoot biomass production, and root density under ten plant species used as green manure: Brachiaria decumbens Stapf. cv. Basilisk, Canavalia ensiformis (L.) DC, Crotalaria juncea L., Crotalaria ochroleuca G. Don, Crotalaria spectabilis Roth, Lablab purpureus (L.) Sweet, Mucuna pruriens (L.) DC, Neonotonia wightii (Wight & Arn.) J.A. Lackey, Pennisetum glaucum L., and Stilozobium aterrimum Piper and Tracy. Results and discussion The highest values of soil pH, exchangeable cations, CEC, and soil available water capacity were found on the plots where Poaceae plants were cultivated, whereas for H++Al3+, C.E.C., soil available water, and soil available water capacity were found on the plots where Fabaceae plants were cultivated. On the plots where C. ensiformis and N. wightii were cultivated, we found the highest shoot dry biomass and root density, respectively. The results highlight the importance to consider plant species from both Poaceae and Fabaceae family used as green manure as soil conditioner (by promoting soil fertility, nutrient cycling, and hydraulic properties into plant root zone), and thus creating a positive plant-soil feedback. Conclusions Our findings suggest that (1) a consecutive green manure practice without any input of fertilizers after 6 years changed positively both soil physical and chemical properties, and improve plant growth (e.g., shoot dry biomass and root density) in tropical savanna climate conditions;and (2) by altering soil fertility, both Poa

关键词： Asinine milk   Nutritional value   Fermentation   Storage stability  

摘要： This study aimed to evaluate the nutritional value and physicochemical characteristics of fresh donkey milk and fermented donkey milk. Furthermore, the impact of the refrigerated storage (4 degrees C, 21 days) on the characteristics of the fermented milk was evaluated. The fermented milk had higher acidity (lower pH values and higher titratable acidity) and presented lower lactose, mineral (calcium, phosphorous, magnesium, sodium, and zinc), and amino acid (mainly essential amino acids) contents than milk. Otherwise, it had a better fatty acid profile (lower saturated fatty acid content, and higher monounsaturated and polyunsaturated fatty acid contents). The fermented milk storage resulted in decreases in the lactose content, improvements in the amino acid profile, and maintenance of the mineral content. However, negative impacts were observed on the fatty acid profile. It can be concluded that both donkey milk and fermented milk donkey present important nutritional value, and the fermented milk could be refrigerated stored up to 21 days.

关键词： High intensity ultrasound   Transglutaminase   Whey protein soluble aggregates   Rheological property   Gelation property  

摘要： A solution (10%, w/v) of whey protein soluble aggregates (WPISA) was pretreated with high-intensity ultrasound (HUS, 20 kHz) for different durations (10-40 min) before incubation with transglutaminase (TGase) to investigate the effect of HUS on the structural, physicochemical, rheological, and gelation properties of TGase crosslinked WPISA. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) results showed that HUS increased the amounts of high-molecular-weight polymers/aggregates in WPISA after incubation with TGase. HUS significantly increased (P < 0.05) the degree of TGase-mediated cross-linking in WPISA, as demonstrated by a reduction in free amino group contents. HUS significantly increased (P 0.05) the particle size, intrinsic fluorescence intensity, and surface hydrophobicity of TGase cross-linked WPISA, but had no significant impact (P 0.05) on the zeta-potential or total free sulfhydryl group content of TGase cross-linked WPISA. The apparent viscosity and the consistency index of TGase cross-linked WPISA were significantly increased by HUS (P < 0.05), which indicated that HUS facilitated the formation of more high-molecular-weight polymers. HUS significantly increased (P < 0.05) the water holding capacity and gel strength of glucono-delta-lactone (GDL)-induced TGase cross-linked WPISA gels. The results indicated that HUS could be an efficient tool for modifying WPISA to improve its degree of TGase-mediated cross-linking, which would lead to improved rheological and gelation properties.

关键词： fir honey   pine honey   thyme honey   botanical origin   Raman spectroscopy   discrimination  

摘要： BACKGROUND The authenticity of honey is of high importance since it affects its commercial value. The discrimination of the origin of honey is of prime importance to reinforce consumer trust. In this study, four chemometric models were developed based on the physicochemical parameters according to European and Greek legislation and one using Raman spectroscopy to discriminate Greek honey samples from three commercial monofloral botanical sources. RESULTS The results of physicochemical (glucose, fructose, electrical activity) parameters chemometric models showed that the percentage of correct recognition fluctuated from 92.2% to 93.8% with cross-validation 90.6-92.2%, and the placement of test set was 79.0-84.3% successful. The addition of maltose content in the previous discrimination models did not significantly improve the discrimination. The corresponding percentages of the Raman chemometric model were 95.3%, 90.6%, and 84.3%. CONCLUSION The five chemometric models developed presented similar and very satisfactory results. Given that the recording of Raman spectra is simple, fast, a minimal amount of sample is needed for the analysis, no solvent (environmentally friendly) is used, and no specialized personnel are required, we conclude that the chemometric model based on Raman spectroscopy is an efficient tool to discriminate the botanical origin of fir, pine, and thyme honey varieties. (c) 2020 Society of Chemical Industry

关键词： Sorghum starch   Acid‐   ethanol treatment   Intrinsic viscosity   XRD   Chain length  

摘要： Acid alcohol hydrolysis of starch is a sustainable chemical method and versatile tool to control molecular weight. Sorghum starch was acid hydrolyzed in ethanol for durations ranging from 24 to 240 h. The native and acid ethanol treated (AET) starches were investigated for their physicochemical, thermal, structural and pasting characteristics. Native starch showed degree of polymerization of 2624 anhydrous glucose units (AGU), amylose content of 26%, swelling power and solubility of 12.2 g/g and 5%, respectively. AET starches showed significantly (p < 0.05) higher solubility (19.8-58.4%) whereas lower values for swelling power (4.3-11 g/g), were observed. The chain length profiles of debranched native and AET sorghum starches, as obtained from high-performance size-exclusion chromatography (HPSEC), indicated preferential degradation of amylose and amylopectin long chains. This led to decrease in intrinsic and pasting viscosities for AET starches. Comparison of X-ray diffractograms (XRD) of native and AET treated sorghum starches showed that there is no change in the diffraction pattern ('A' type) upon treatment however the relative crystallinity was observed to decrease upon hydrolysis. Granule structure remained intact however, with AET birefringence loss in some granules was observed, which indicated change in radial orientation of double helices and chain mobility at granule centre. The results indicated that sorghum starch can be tailored by AET and could be used in the food industry for various food formulations.

关键词： Bioaccessibility   Biscuit   Stability   Fortification   Iron   Whey protein concentrate  

摘要： Iron deficiency anemia (IDA) is one of the major health issues prevalent in India. The fortification of food with iron salts can affect their sensory, physico-chemical properties and may also generate harmful free radicals causing oxidative stress in the intestinal lumen. Whey protein concentrate was complexed with iron using techniques like centrifugation, ultrafiltration and spray drying. Biscuits were fortified with spray-dried whey protein concentrate-iron sulphate (WPC-FeSO4) complex at five different concentrations of iron i.e. 10,15,20,25 and 30 mg/100 g. Sensory acceptability of the biscuits was not significantly (p > 0.05) affected when fortified with WPC-Fe complex with upto a level of 25 mg Fe/100 g. No significant difference (p < 0.05) in the diameter, thickness, spread ratio, fat, protein, acid insoluble ash, moisture, phytate content and color was observed for the control, ferrous sulphate and WPC-Fe complex fortified (25 mg/100 g) biscuit samples. WPC-Fe complex fortified biscuits exhibited higher storage stability and a significantly (p < 0.05) higher bioaccessibility of iron under in vitro conditions as compared to FeSO4 fortified biscuit. Therefore, biscuits can be fortified with upto 25 mg iron in the form of WPC-Fe complex/100 g of biscuits without significantly altering their physicochemical properties with a higher bioaccessibility of iron.

关键词： Ultrasound assisted-vacuum tumbling   Myofibrillar proteins   Protein oxidation   Protein structure   Physicochemical properties  

摘要： The present research aimed to investigate the effects of high-intensity ultrasound (HIU, 20 kHz, 0 W, 100 W, 300 W and 500 W)-assisted vacuum tumbling (UVT) for 60 min and 120 min on the oxidation and physicochemical properties of the pork myofibrillar proteins (MPs). Compared with the vacuum tumbling (VT) groups without the HIU assistance, the carbonyl content increased, while the total sulfhydryl (SH) content was reduced with the increase of HIU power and treatment time (P < 0.05). The reactive SH content was increased significantly after treated by UVT with 300 W compared with the VT group (P < 0.05) regardless of the treatment time. Similarly, the surface hydrophobicity (S0), the intrinsic tryptophan intensity, and the solubility in the UVT group (300 W) were remarkably higher than those of the VT group (P < 0.05). In contrast, the alpha-helix content and the particle size of MPs significantly decreased when the HIU power was at 100 W and 300 W (P < 0.05). The results suggest that UVT treatment could change the structure and physicochemical properties of MPs accompanied by protein oxidation.