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关键词： Arenga pinnata starch   chitosan   digestion   heat-moisture treatment   physicochemical properties  

摘要： In vitro digestibility and physicochemical properties of chitosan (CS)-modified Arenga pinnata starch (APS) after heat-moisture treatment (HMT) were evaluated. HMT would limit the enzymatic hydrolysis of APS and the digestion rate of HMT-APS-CS was further reduced with the decrease of CS molecular weight. CS and HMT inhibited the solubility (SOL) and swelling power (SP) of APS, and the inhibition effect was more obvious with the decrease in CS molecular weight. Changes in the pasting properties of the CS-modified APS indicated that the initial structure of the APS granules was destroyed with the formation of a denser structure. The increase of the relative crystallinity and the aggregation of the APS granules were related to starch cross-linking confirmed by Fourier transform infrared. The interactions between CS and APS granules after HMT greatly altered granular morphology and internal structure of APS. Therefore, the improvements of SDS and RS of HMT-APS-CS were mainly related to CS covering the surface of the APS granules, granule aggregation and HMT-induced changes in the internal structure of the starch granule.

关键词： UV-B   1-MCP   Fresh-Cut   Peach   Browning  

摘要： Fresh-cut peaches are prone to quality deterioration, including browning, which is detrimental to their shelf life and marketability. Physiochemical changes in the fruit treated with the combination of a hormetic dose of UV-B irradiation (1.46 kJ m(-2)) and 1 mu l L-1 1-MCP fumigation were assessed. The combined treatment effectively maintained the fruit quality as indicated by the inhibited weight loss and browning, which was associated with the enhancement of total phenolic content by UV-B, and restraint activities of polyphenol oxidase and peroxidase by 1-MCP. Meanwhile, a stable membrane was suggested based on the facts of the reduced membrane peroxidation and improved unsaturated fatty acid proportion. Moreover, the retarded energy deficit was coupled with moderated respiratory metabolism. In summary, the combination of UV-B and 1-MCP treatments compromised phenolic metabolism, enhanced membrane stability, and moderated respiratory metabolism, and hence can be used to extend the shelf life of fresh-cut peaches.

关键词： Littoral zones   Species   Abundance   Habitats   Disturbances  

摘要： The intertidal zone is unique in terms of its ecological conditions and faunal assemblages. Molluscs form a key link in the food chain and have a high socioeconomic value for coastal fisheries. Intertidal habitats of Karnataka are modified by anthropogenic disturbances which threaten the animals living there including molluscs. The present study is designed to know the diversity of molluscs of Karnataka coast, India and to understand the factors influencing variations in molluscan diversity. Thirteen intertidal habitats of coastal Karnataka were selected for the study of which six sites were visited on monthly basis from February 2017 to January 2018. Molluscan shells were collected from these sites using quadrates of 0.25m(2) from fixed intervals. The other sites were visited once during the study and molluscs were collected using quadrates and by handpicking. Molluscs were brought to the laboratory, preserved in 70% alcohol, and identified using the standard identification keys. Abiotic parameters such as air temperature, water temperature, wave frequency were noted in the field. Environmental variable such as precipitation was studied. Physico-chemical parameters of water (salinity, electrical conductivity, pH of water) were analysed using standard methods. A total of 36 species of molluscs were recorded from the intertidal habitats of coastal Karnataka. It includes 21 species of gastropods and 15 species of bivalves. Bullia melanoides, Saccostrea cucullata and Echinolittorina leucostica were found throughout the study. Abranda myeformis, Mactra luzonica, Sunetta sp, Turricula tornata fulminata were the rare shells found on the beaches of coastal Karnataka. The abundance of molluscs was observed post-monsoon in all the sites. Species richness of molluscs was more in post-monsoon in all the intertidal areas except beaches of Kaup and Kota-Padukere. Shannon-Weiner index and Simpsons index were more in post-monsoon in the beaches of Someshwar, Panambur, Sasihithlu,

关键词： Physicochemical properties  

摘要： This study was aimed to optimize mixtures of ashwagandha powder and giloy powder along with wheat flour for the production of sponge cake. Ashwagandha powder and giloy powder were applied 2 to 5% and 5 to 8%, and yogurt was used as fat-replacer 50%. Optimization of the formulation was based on the sensory evaluation obtained through 9-point Hedonic scale. The results revealed that sponge cake incorporated with 2% ashwagandha powder and 5% giloy powder, i.e. ashwagandha giloy fortified sponge cake (AGF(SC-I)) was most appreciated by the tasting panel members with overall acceptability. Protein (%), fat (%), carbohydrates (%), energy (%), TPC (mg GAE/100 mg), TFC (mg QE/100 mg), and IC50 (mg/ml) value decreased during the storage period of 5 days, i.e. from 15.25 +/- 0.03 to 13.15 +/- 0.10;12.44 +/- 0.04 to 12.2 +/- 0.16;33.62 +/- 0.31 to 31.99 +/- 0.008;307.44 +/- 1.03 to 290.36 +/- 0.96;14.82 +/- 0.13 to 7.694 +/- 0.10;5.111 +/- 0.36 to 3.823 +/- 0.08;and 13.82 +/- 0.10 to 8.807 +/- 0.08 respectively. Novelty Statement Wheat flour sponge cake was prepared with the incorporation of ashwagandha and giloy as AGsFSC. Yogurt was used in place of butter in order to prepare low-fat AGFSC. Shelf-life analysis was performed to study the stability of AGFSC for 5 days.

关键词： Drying  

摘要： The dried black carp was studied based on moisture content, color, aerobic plate count (APC), total volatile basic nitrogen (TVB-N), peroxide value (POV), thiobarbituric acid reactive substance (TBARS), fatty acids, free amino acids, and nucleotides to explore the physicochemical properties changes. After drying for 12 hr, moisture content dropped to 42.53% and color changed obviously. L* value decreased and a* and b* values increased. APC and TVB-N results indicated fillets had high food safety. POV and TBA both were on the rise in fillets, reaching the maximum values of 0.08 mg/100 g and 2.33 mg MDA/kg, respectively. Monounsaturated fatty acids and polyunsaturated fatty acids were oxidized and decomposed, which led to the increase of saturated fatty acids absolute content. From the results of equivalent umami concentration, fillets reached the maximum value of 9.04 g MSG/100 g. The longer the drying time, the worse the taste quality in products. Practical applications In order to investigate the quality changes of black carp during drying, physical properties, lipid oxidation, and nonvolatile flavor substances were analyzed. From this article, it can be found that during the process of drying, the black carp was in a safe state. The results of this article provided theoretical and technical support for black carp.

关键词： Capsaicin   Interfacial tension   Carbohydrates   Modified starch   Emulsion stability  

摘要： The objective of this study was to evaluate the individual and combined use of gum Arabic (GA), OSA-modified corn starch (EMCAP), and stearic acid-modified malt (MALT) as emulsifiers of Capsicum oleoresin emulsions. Emulsions were investigated regarding their morphological and physicochemical properties and capsaicin retention. The synergism between GA: MALT and EMCAP: MALT was able to reduce the interfacial tension values (< 8.7 mN/m) and enabled the formation of kinetically stable emulsions (Turbiscan stability index < 4.4). Steric forces and increased viscosity also contributed to the stability of these emulsions. Also, MALT promoted an increase in droplet size due to the presence of whole starch granules. The impact of different formulations on the color parameters resulted in Chroma values ranging from 31.4 +/- 0.7 to 61.2 +/- 0 and hue angle between 42.1 degrees +/- 0 to 60.4 degrees +/- 0.1, characterized by orange and red tones. Our study found that the interaction of MALT with gum Arabic and EMCAP promoted an increase capsaicin retention and viscosity of Capsicum's oleoresin emulsion, showing the potential of these carbohydrates for further use as encapsulant materials in spray drying microencapsulation.

关键词： Rheology   Concentrated suspensions   Design of experiments   Physico-chemical properties   Modelling  

摘要： Concentrated suspensions are fluids that exhibit complex non-Newtonian and time-dependent rheological behaviour. The literature offers many structural models that typically take into account the influence of the viscosity of the continuous phase, the volume fraction of the dispersed phase and the geometrical characteristics of suspended particles. Due to their complex formulation, energetic suspensions require also the consideration of many other physicochemical factors. Each of these factors may affect the rheology of the suspension but can also act in synergy or antagonism with the other factors leading to complex couplings. In the present paper, the effect of all physicochemical properties of the solid particles on the suspension viscosity is taken into account. The physicochemical characteristics of both solids and fluids were first determined, which were used to build a design of experiments with the viscosity of the different formulations as the response. Thanks to multilinear regression and analysis of variance of the experimental data, combined with a mechanistic approach, a model was established, correlating the viscosity of the studied suspension to the shear rate and physicochemical properties of the solid phase.

关键词： Physicochemical properties  

摘要： Stabilized selenium nanoparticles have been synthesized via the interaction of sodium selenite with ascorbic acid in aqueous solutions of sodium carboxymethyl cellulose with degree of substitution 0.97 and degree of polymerization 810. Structure and physicochemical properties of the sodium carboxymethyl cellulose solutions containing stabilized selenium nanoparticles have been studied. Formation of the metal complexes due to the donor-acceptor interactions between the carboxymethyl groups of carboxymethyl cellulose and selenium nanoparticles has been revealed by means of IR-Fourier spectroscopy. Size and shape of the selenium nanoparticles present in the structure of sodium carboxymethyl cellulose have been determined by means of atomic force microscopy, electronic absorption spectroscopy, and dynamic light scattering. It has been stated that size and shape of the selenium nanoparticles depend on the conditions of the reduction reaction and concentration of sodium selenite in the solutions of sodium carboxymethyl cellulose.

关键词： Chlorine compounds  

摘要： A novel monomer for the synthesis of polyimides, 5-methyl-1,3-phenylene-bis-4-oxyphthalic acid dianhydride was developed. The synthesis was carried out in three stages: the reaction of nucleophilic nitro substitution of 4-nitrophthalonitrile with 5-methylresorcinol (orcinol) potassium salt and subsequent hydrolysis of the nitrile groups have afforded 5-methyl-1,3-phenylene-bis-4-oxyphthalic acid, dehydration of which has given the corresponding dianhydride. A series of new thermoplastic high molecular weight polyetherimides based on 5-methyl-1,3-phenylene-bis-4-oxyphthalic acid dianhydride and several aromatic diamines of various structures were synthesized by the method of one-stage catalytic polycondensation in a benzoic acid melt. Inherent viscosity and weight-average molecular mass of the polyetherimides have been of 0.28-1.20 dL/g and (33-114) x 10(3), respectively. The polyetherimides have been soluble in chloroform, THF, DMF, DMAA, N-methylpyrrolidone, and DMSO and have revealed film-forming properties. According to the DSC and wide-angle X-ray scattering data, the polyetherimides have been found completely amorphous, the glass transition temperature being in the 185-307 degrees C range.

关键词： Hydrolysis   Glycerides removal   gamma-Oryzanol   Subcritical water   Condition effects  

摘要： A comparative study on physicochemical hydrolysis methods, including acid-catalyzed, base-catalyzed, and subcritical water hydrolysis, for glycerides removal prior to subsequent gamma-oryzanol purification from rice bran acid oil (RBAO), is presented. The effects of hydrolysis conditions on the residual levels of glycerides and gamma-oryzanol in RBAO were first investigated for each method. It can be concluded that the acid-catalyzed hydrolysis was not a suitable hydrolysis method for this application as it provided a low glycerides conversion level of ca. 30% using 2 N H2SO4 at 80-100 degrees C, despite the long reaction time (> 60 min). For the base-catalyzed hydrolysis, 100% glycerides removal was achieved at the most suitable condition, which was suggested to be at 2.5 N NaOH, 90 degrees C and 5-10 min. At this condition, a relatively high residual level of gamma-oryzanol of ca. 57-66% was obtained. For the subcritical water hydrolysis, the results suggested that gamma-oryzanol was hydrolyzed more rapidly than glycerides, and the most suitable condition for subcritical water hydrolysis was at 220 degrees C for 10 min. At this condition, high glycerides removal of > 95% was achieved while the remaining amount of gamma-oryzanol was still acceptable (50%).