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关键词： Additive   {LiBr plus water} system   Absorption refrigeration   Phase equilibria physicochemical properties  

摘要： Due to the good performance in absorption systems, lithium bromide plus water solution is the most widely used working pair. The disadvantages of this system, including, in particular, the tendency to crystallize, makes it necessary to search for new solutions. Properly choosing additives to conventional lithium bromide aqueous solution to improve the performance of the cycle is an important part of the lithium bromide absorption refrigeration studies, including ours. This paper is a continuation of our comprehensive research in this area. Mixtures consisting of lithium bromide + lithium acetate + water, and lithium bromide + lithium lactate + water, and lithium bromide + lithium trifluoroacetate + water are thought to be promising alternatives to the conventional system. In this research, the influence of three lithium salts on solubility are presented. Based on solubility measurement, two additives are selected and vapour pressure, and physicochemical properties for {lithium bromide + lithium acetate, or lithium lactate + water} systems is presented. Measurements of vapor pressure, dynamic viscosity, and the liquid density are carried out over a wide range of temperatures and compositions. Empirical equations are used to correlate dynamic viscosity, and density data. Based on the comparison between experimental results presented here and literature data for. a conventional binary system, the effect of the additive on physicochemical and thermodynamic properties is characterized and the possibility of the potential application of such new ternary systems in absorption refrigeration technology is determined. (c) 2021 Elsevier Ltd.

关键词： Buffalo milk   High-pressure homogenisation   Microstructure   Melting  

摘要： This study aimed to determine the physicochemical, textural, and microstructural characteristics of buffalo milk ice cream produced from high-pressure homogenisation (HPH) treated ice cream mix. Ice cream mix was subjected to 0 (control), 30, 60, 90, 120, or 150 MPa. HPH increased the firmness and consistency value of mixes, whereas it decreased cohesiveness and index of viscosity values. Also, HPH improved the lightness, redness, and yellowness of the mix. The mean particle size of HPH-treated mix samples was lower than the control, except HPH-150. The hardness of ice cream samples was between 14.30 and 77.81 N, in which HPH increased hardness value with the increasing pressure. The overrun of ice cream samples ranged from 19.93 to 45.15%, and HPH decreased it. HPH significantly improved resistance to melting in the ice cream. Scanning electron microscopy images revealed that HPH reduced the size of air bubbles. HPH at 150 MPa resulted in a foamy structure in the ice cream. HPH can alter the hardness, microstructure, and melting characteristics of buffalo milk ice cream. Products with improved properties may be developed by further modifying the formulation and processing parameters.

关键词： Porphyra haitanensis   Polysaccharide   Antioxidant activity   Immunoregulatory effect  

摘要： To explore effect of the structural properties of porphyra haitanensis polysaccharide on its biological activity, degraded porphyra polysaccharides were separated and purified by Cellulose DEAE-52 and Sephadex G-100 chromatography, obtaining three purified components (P1, P2 and P3). All the three components were sulfate polysaccharides containing the repeating units of -> 3) beta-D-galactose (1 -> 4) 3,6-anhydro-alpha-L-galactose (1 ->, and -> 3) beta-D-galactose (1 -> 4) alpha-L-galactose-6-S (1 ->, and -> 3) 6-O-methyl-beta-D-galactose (1 -> 4) 3,6-anhydro-alpha-L-galactose (1 ->. The molecular weight of the three fractions was measured to be 300.3, 130.4 and 115.1 kDa, respectively. Their antioxidant activity was investigated by the determination of the free radical scavenging effect and ferric reducing power. It was found that P1, P2 and P3 possessed marked antioxidant activity. It was also found that they appreciably enhanced the proliferation, phagocytic ability and nitric oxide secretion in RAW264.7 cells. Lower molecular weight and higher sulfate content were beneficial to bioactivities of P. haitanensis polysaccharides. Overall, P2 and P3 possess superior immuno-modulatory activity to that of P1 and PHP. Thus, the current work will provide the basis for the better utilization of P. haitanensis to develop the related functional foods.

关键词： Ginseng insoluble dietary fiber   Alkaline hydrogen peroxide treatment   Physicochemical and functional properties  

摘要： The influence of alkaline hydrogen peroxide (AHP) treatment of ginseng insoluble dietary fiber (IDF) on physicochemical and functional properties was investigated in this study. The chemical treatment resulted in porous IDF with wrinkled surface and loosened inner structure. Comparing to the unmodified, modifying ginseng IDF increased the water holding capacity (WHC), water swelling capacity (WSC) and oil retention capacity (ORC) by 32.6%, 29.8% and 32.7%, respectively. The chemical modification caused diminution in isoquercetin, ellagic acid, resveratrol, epicatechin and ferulic acid contents and unfavorable decreases in antioxidant activities. AHP treatment improved nitrite-adsorption capacity, cholesterol-adsorption capacity, glucose adsorption capacity and alpha-amylase inhibitory activity. X-ray diffraction and Fourier transform infrared (FT-IR) spectroscopy analyses showed that AHP treatment led to major alterations in the structure of IDF. Thus, AHP modified ginseng IDF, as a novel ingredient could find potential applications in the development of both plant and meat based products.

关键词： Red pepper juice   Spray drying   Efficiency   Energy consumption   Powder properties   Morphology  

摘要： The aim of this study is to investigate the influence of the encapsulating agents (maltodextrin (MD), whey protein isolate (WP), and gum arabic (GA)) and their blends (MD + WP, MD + GA, WP + GA, and MD + WP + GA) on the powder yield, drying ratio, productivity, drying rate, physicochemical, bulk, reconstitution, and morphological properties of the red pepper juice powders (RPJP) and to calculate the energy efficiency of the spray dryer. A pilot-scale spray dryer (180/80 degrees C inlet/outlet air temperature, 392 kPa atomization pressure, 1.54 m(3)/min air flow rate, and a 12.0 +/- 0.2 degrees Bx feeding concentration) was used for the drying experiments. The acceptable powder yield (52.48-94.25%) and specific energy consumption values (7.39-9.72 MJ/kg H2O) were obtained. The RPJP presented moisture content and water activity values lower than 10% and 0.367. The red pepper juice powders were found to be highly dispersible (88.34-95.18%), soluble (solubility time and index are 9.75-77.25 s and around 99%), and easly wetted (9.75-122.00 s). The average particle sizes of the RPJPs were 14.92 mu m, 19.68 mu m, 19.36 mu m, 17.58 mu m, 19.96 mu m, 19.41 mu m, and 18.72 mu m for RPJP + MD, RPJP + WP, RPJP + GA, RPJP + MD + WP, RPJP + MD + GA, RPJP + WP + GA, and RPJP + MD + WP + GA respectively. Despite the low powder yield and high water activity value, RPJP + MD exhibited superior (bulk density, flowability, cohesiveness, wettability and solubility times) or statistically similar (productivity, moisture content, browning index, porosity, dispersibility, and hygroscopicity) properties compared to other powders. [GRAPHICS] .

关键词： Konjac glucomannan   Degradation   Ozone   Microwave   Physiochemical properties  

摘要： The degradation and modification can greatly improve solubility properties of Konjac glucomannan (KGM) and enhance its capacity to interact with other polymers. Hereby, low-viscosity oxidized KGM (OKGM) was prepared by a combined method of ozone assisted with microwave. In this study, we mainly discussed the effect of ozonemicrowave treatment on the structure and properties of KGM. The experimental results indicated that ozonemicrowave treatment caused a time-dependent (30, 60, 80, 100, 120 min) degradation of KGM, and longer treatment time led to lower molecular weight (Mw) and apparent viscosity of KGM. The OKGM depolymerized by 120 min ozone-microwave showed a good water solubility index (85.08%) and low swelling power (4.29 g/g). Besides, determination of carbonyl contents showed that ozone-microwave introduced more carbonyl contents into KGM than ozonation alone. Moreover, FT-IR and XRD spectra suggested that the chemical structure and crystallized region of native KGM was altered after ozone-microwave treatments. Compared to native KGM, the thermal stability of OKGM decreased while its whiteness was enhanced. In addition, the rheological properties of OKGM differed markedly from native KGM due to the changes in Mw and molecular structure. This study provides a new pathway for efficiently producing depolymerized KGM to meet some practical production needs, and may be useful for future research and development of OKGM.

关键词： Table Grapes   Raisins   Organic   Turkey  

摘要： This study was conducted to determine quality criteria of raisins served to taste of consumers in local bazaars and identify their compliance with the standards. Raisin samples randomly taken from local bazaars in Midyat town of Mardin province and Besiri town of Batman province were used as the material of the study. A total of 30 samples (15 from each town) were subjected to physicochemical analyses (100-raisin weight, number of raisins per 100 g, average raisin width, average raisin length, average number of seeds, average seed weight, raisin skin color parameters, chroma and hue angle, pH, TSSC (total soluble solid contents), maturity index, water content, ash content, specific gravity and total acidity). According to size characteristics specified in Turkish Food Codex, in terms of number of raisins per 100 g, all samples, except for M-2 (large), were classified in jumbo (very large) class. In terms of chroma values, M-13 (15.97) and B-3 (6.51) samples had the greatest color saturation and M-11 (3.64) and B-13 (0.22) samples had the opaquest colors. In terms of hue angle values, M-3 (312.59) and B-13 (112.28) samples had the darkest blue color and M-10 (54.09) and B-1 (85.92) samples had the darkest red-purple color. In terms of pH values, M-6 (4.68) samples were classified as moderately acidic foods and all the others were classified as acidic foods. Despite the lack of vertical food codex for raisins in Turkish Food Codex, compliance is required with the horizontal regulation provisions (labeling, contaminants, pesticide, additives, microbiological criteria and etc. applied to all foodstuffs). Present findings revealed that there were no standard productions in raisins sold in public bazaars. Thus, it was concluded that improper storage and marketing conditions could pose serious risks on public health. Therefore, raisin topic should urgently be issues and relevant controls should be made accordingly. A similar study was not conducted in Midyat and Besiri tow

关键词： alternative calcium   bioactive compounds   pre-treated cuttlebone powder  

摘要： This study was aimed to investigate the potential use of pre-treated cuttlebone powder (CBP) as an alternative calcium source by evaluating the physicochemical properties of CBP pre-treated with distilled water (CBP1), 1% acetic acid (CBP2), and 2% sodium hydroxide (NaOH) solutions (CBP3). Proximate analysis revealed ash as the major component of all samples. The presence of phenols, flavonoids, alkaloids, and glycosides were detected but tannins appeared to be absent in cuttlebones. Mineral analysis indicated that CBP was rich in calcium, which means the material may be considered as a potential calcium source for food products or calcium supplements. The bulk density of CBP2 was significantly lower (p < .05) than those of CBP1 and CBP3, and the water holding capacity (WHC) of CBP1 was significantly higher (p < .05) than those of CBP2 and CBP3. The high bulk density, water and oil holding capacities of CBP demonstrated its potential use as a functional food ingredient.

关键词： Hydrodynamic cavitation   Orifice plate   Sugarcane juice   Microbial reduction   Physicochemical properties  

摘要： An orifice based hydrodynamic cavitation system was developed for treating fresh sugarcane juice, non-thermally. The effect of hydrodynamic cavitation treatment parameters such as pressure (2.5, 3, and 3.5 bar), processing time (10, 20, 30, 40 min), and type of orifice plate geometry on the physicochemical attributes such as temperature rise, pH, titratable acidity (TA), total soluble solids (TSS), viscosity, change in colour and microbial load of the sugarcane juice were investigated. The maximum rise in temperature during the treatment was 22 degrees C at 3.5 bars with the 17 number of orifices. The pH decreased from 4.94 to 4.64 and TSS significantly reduced (p < 0.01) from 20 to 13 degrees Brix depending on the severity of the treatment. The reduction in viscosity was in the range of 3-48%. The maximum colour change in the juice could be observed when treated at an inlet pressure of 3.5 bar for a processing time of 40 min with a plate having 17 numbers of orifices. The maximum microbial load inactivation from 5.53 log(10) CFU/mL to 3.3 log(10) CFU/mL was observed at the highest pressure, processing time, and orifices.

关键词： Cavitation jets   okara protein   Raman spectrum analysis   structure  

摘要： The structural andphysicochemical properties of okara protein (OP) subjected to different cavitation jet (CJ) treatment times (0-15 min) were analyzed. In this study, the microstructure and apparent morphology of OP were analyzed by Raman spectrum, fluorescence spectrum, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and atomic force microscopy (AFM). Physicochemical properties, such as emulsion ability (EA), emulsion stability index (ESI), foaming characteristics (FC), foaming stability (FS), and solubility analysis of the OPs, were characterized. Raman spectrum analysis showed that CJ treatment caused increases in the ordered structure of OPs (alpha-helix, beta-sheet, and beta-turn), and the disulfide bond g-g-g and g-g-t modes, while it caused a decrease in the t-g-t mode. However, the tertiary structure of OP unfolded and mostly degraded into small subunits because of higher cavitation, shear and temperature effects. AFM observation indicated that CJ resulted in a more uniform distribution of OP. Moreover, changes in the structure of OP significantly affected its functional properties. The results showed that when CJ treatment time was 10 min, the solubility of OP was up to (28.72 +/- 1.26)%, the soluble protein content of okara was up to (10.44 +/- 0.03) g/100 g, and interface properties were better. In summary, OP has great potential for application in the food area, especially in emulsifying agent and foam system. Practical Application The cavitation jet technology improves the structure and physical and chemical properties of the protein extracted from soybean residue (okara) and provides new ideas for the further development and utilization of soybean residue protein, which may lead to the production of high-value-added functional ingredients from the processing of soybean byproducts.