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关键词： Chinese yam flour   Crystallinity   Growth stage   Rheological characteristics   Thermal property  

摘要： Chinese yam has been widely used in food products. The growth stage significantly influences the qualities of Chinese yam. In this work, the physicochemical properties and microstructure of Chinese yam flours from expansion stage (ES-FF) and dormant stage (DS-FF) were investigated. The amylose content of DS-FF was lower than ES-FF, while the fat content of DS-FF was higher. The size and shape of Chinese yam flour granules at two growth stages remained consistently. ES-FF and DS-FF presented A- and C-type crystalline structure, respectively. DS-FF had a lower crystallinity and a higher short-range order than ES-FF. Dormant stage induced the formation of more amylose-lipid complex and ordered structure in granule. The values of T-o, T-p, T-c and enthalpy indicated that DS-FF had a higher thermal stability and a more compact structure than ES-FF. Moreover, Chinese yam flour showed a good elasticity and stickness with a high viscosity.

关键词： Energy utilization  

摘要： In this research, Ginkgo biloba L. seeds (GBS) were freeze-dried, infrared-dried, hot-air dried, and pulsed-vacuum dried. A detailed analysis of their drying kinetics (drying curve, drying rate curve, effective moisture diffusivity, mathematical modeling), shrinkage and energy efficiency (specific moisture extraction, specific energy consumption), and physicochemical properties (soluble solids, total sugar, reducing sugar, ascorbic acid, phenolics, and tannins) were performed. Results showed drying methods had various effects on different indexes and were confirmed by principal component analysis. The drying process occurred in the falling-rate period. The effective moisture diffusivity values amongst various drying methods ranged from 3.5 x 10(-8) to 7.6 x 10(-8) m(2)/s, which were within the normally expected range for food materials. The exponential model best fitted the experimental results for drying with coefficient of determination (R-2 ) > .981 and root mean square error, sum of square error, and reduced chi-square closer to zero than the parabolic and inverse-logarithmic (Log3p1) models. The freeze-dried GBS had the highest nutritional (statistically the same with the fresh GBS) and lower shrinkage;nevertheless, it had the lowest moisture extraction rate and the highest energy consumption. Hot-air dried GBS had the highest shrinkage and lowest nutritional retention. Infrared-dried GBS was superior with the highest non-tannic phenolic, proanthocyanidins content, effective moisture diffusivity, drying rates, and energy efficiency. The current findings indicate that infrared drying is a promising drying technology for GBS and has the potential to be applied on a commercial scale. Practical application Ginkgo seeds (GBS) are utilized as functional food across Asia. In China, ginkgo trees' extensive cultivation has surpassed market requirements, as GBS production could reach 60,000 tons per year. Therefore, there is an urgent need to find new opportunities to ta

关键词： Protein   Lecithin   Interaction mechanism   Salting-out effect  

摘要： In this study, the effect of phospholipids on the physicochemical properties of myofibrillar proteins (MP) solution was investigated at different NaCl concentration (0.3-0.7 mol/L). The results indicated the phospholipids addition increased the average particle size (i.e., from 1277-651 to 1546-1087 nm at 0.3-0.7 mol/L NaCl) and turbidity (i.e., from 0.323-0.139 to 0.729-0.551 at 0.3-0.7 mol/L NaCl) due to the enhanced hydrophobic interaction, and decreased the modulus of MP solution due to the reduction of disulfide bonds between MP. At 0.3-0.5 mol/L NaCl concentration, the formation of MP-phospholipids (MP-P) complexes resulted in the decreased protein solubility (i.e., 50.93%-75.67% and 41.28%-74.60% for MP and MP-P, respectively) and the increased viscosity of MP solution. However, at NaCl concentration close to 0.7 mol/L, the rheological properties of MP-P complexes did not change significantly like that of MP groups. This indicated the phospholipids addition could inhibit the salting-out effect of MP due to enhanced hydrogen bond between MP and water. Moreover, the phospholipids addition enhanced the emulsifying activity and emulsifying stability of MP solution at a high NaCl concentration (0.7 mol/L).

关键词： calcium carbonate   nanoparticles   Portland cement   silicates   TEM  

摘要： The addition of calcium carbonate nanoparticles (nano-CaCO3) accelerates the hydration of Portland cement improving its mechanical properties. Conversely, nano-CaCO(3)addition leads to reduction in the water required during initial PC hydration. Therefore, the use of a correct water-to-powder ratio is fundamental for manipulating this hydraulic cement. This study evaluated the effect of nano-CaCO(3)addition and different water-to-powder ratios on the physicochemical properties of white Portland cement (WPC). WPC was associated to different concentrations of nano-CaCO3, and the following experimental groups were created: G1a (no nano-CaCO3);G2a (0.5% nano-CaCO3), G3a (1% nano-CaCO3), G4a (2% nano-CaCO3), and G5a (5% nano-CaCO3). The setting-time (ST), compressive strength (CS), dimensional change (DC), solubility (S), and pH were assessed (24 hr and 30 days). Next, WPC + 5% nano-CaCO(3)was manipulated varying the water-to-powder ratio: G1b (WPC/0.33 ml);G2b (WPC/nano-CaCO3/0.33 ml);G3b (WPC/0.29 ml);G4b (WPC/nano-CaCO3/0.29 ml);G5b (WPC/0.26 ml);and G6b (WPC/nano-CaCO3/0.26 ml). The tests were repeated. The data analysis (2-way ANOVA and Tukey test,alpha= 5%) demonstrated that ST was shorter for samples containing nano-CaCO3(p < .05). Reduction in CS was observed for all groups at 30 days, except G5a, G2b, and G6b (p < .05). DC and S had no statistical difference among groups (p > .05) independently of nano-CaCO(3)water-to-powder ratio. After 30 days, there was significant reduction in pH for G3a and G6b (p < .05). The different concentrations of nano-CaCO(3)and water-to-powder ratios affected the physicochemical properties of WPC, especially the setting-time and compressive strength.

关键词： Mussel proteins   SDS-PAGE   Rheology   Gels   Thermal drip   Texture  

摘要： The aim of the study was to determine selected characteristics of surimi-like material (SLM) made from the muscle tissues of Sinanodonta woodiana (Lea, 1834) freshwater mussels. The research material consisted of unwashed mussel muscle homogenate as the control sample-C, mussel muscle tissue twice washed with water (SLM-W) and sample washed with NaCl at a concentration of 0.169 mol/L as well as water (SLM-S). A raw control sample and surimi like-materials were analysed using the SDS-PAGE technique. They were also tested using the DMTA method (dynamic mechanical thermal analysis) while heating the samples up to 80 degrees C and cooling to 20 degrees C. The thermal drip and texture of gels after heating (75 degrees C, 30 min) were also determined. The washing procedure had a significant impact on the protein composition of the SLMs. A significantly (p < 0.05) higher percentage of proteins with molecular weights of 270-273 kDa and 105-110 kDa (corresponding to specific filamin isoforms), as well as 42-43 kDa (corresponding to actin), were found in the SLMs compared to sample C. Ccorrelation analysis confirmed a strong positive relationship between the percentage share of the above proteins and the values of the elasticity modulus (r >= 0.84) and firmness (r >= 0.88) of SLM gels. The SLM-S sample was characterised by the lowest significant (p < 0.05) thermal drip values. During heating, the rheological traits of all samples changed at two stages: from 20 to 50 degrees C and over 50 degrees C. The highest dynamics of variation in the elasticity modulus (G ') value were noticed at temperatures exceeding 50 degrees C in all samples. The G ' values in the SLM samples were significantly greater than the values in sample C. The analysis revealed a strong correlation (r >= 0.81) between the determinants of the texture of the SLM samples and their rheological parameters. Sample SLM-W was the one with the highest firmness and elasticity values. The analysis showed that the textu

关键词： Non-centrifugal cane sugar   Palm sugar   Coconut sugar   Physicochemical property   Antioxidant activity   Volatile component  

摘要： Unrefined non-centrifugal sugars in Southeast Asia emanate from various plant sources including sugarcane, palm, and coconut. To assess food and flavor characteristic differences of these unrefined sugars, seven cane, three palm, and two coconut sugars were evaluated in term of their physicochemical, antioxidant, and volatile flavor properties. Results indicated that unrefined sugars from cane had significantly higher ICUMSA color value than palm and coconut sugars, yet they possessed comparable total soluble solid levels. Cane sugars also presented superior phenolic and flavonoid contents and antioxidant activities, particularly in Thai and Japanese products. Each sugar had distinct volatile flavor composition, comprising acids, Maillard reaction products (furanone, pyrazine, furan, and pyrrole), aldehydes, alcohols, and sulfurs. All traditionally made unrefined sugars had significantly greater Maillard reaction products and less acetic acid than in industrially manufactured cane sugars. Then, propanoic acid and [R-(R*,R*)]-2,3-butanediol were solely major volatiles in palm sugars from Thailand. Additionally, mass spectrometry-based electronic-nose (e-nose) profiling detection provided specific ion masses from various volatile components as potential chemical markers in monitoring aroma characteristic of unrefined sugars and differentiated these sugars into nine statistical clusters based on their materials and origins, wherein palm sugars from Thailand and Indonesia, as well as cane sugars from Thailand and Japan, had comparable volatile profiles.

关键词： Pasteurization  

摘要： In this study, organic intermediate moisture raisin was pasteurized with microwave and conventional pasteurization methods. The thermal resistance (D and z values) of the target yeast, Zygosaccharomyces rouxii, was determined for both methods at different temperatures 60 degrees C, 70 degrees C, and 80 degrees C and at different time intervals. The effect of pasteurization methods on the quality properties of raisin samples was investigated. The D values of Z. rouxii were found as 6.50 +/- 0.49, 2.96 +/- 0.02, 1.91 +/- 0.01 min for conventional treatment and 3.46 +/- 0.31, 2.02 +/- 0.14 and 1 +/- 0.01 min for microwave treatment at 60celcius, 70celcius, and 80celcius, respectively. F-85(37) values for 5-log reduction and come-up time significantly decreased after microwave pasteurization. Brix, acidity, and color values were preserved better by microwave treatment. Hydroxymethylfurfural content of the microwave pasteurized samples was found 42% less than the samples pasteurized conventionally. Microwave pasteurization can be alternatively used for the conventional method for raisin improving quality with less heating time. Practical applications Microwave heating needs less come-up time rather than conventional pasteurization. Decreasing process time provides advantageous via the costs and energy saving so organic intermediate moisture fruits that are perishable can be safely pasteurized by a microwave method for longer shelf life in the industry. Z. rouxii, which may be found in high sugar content foods, can be inactivated to the target log that provides the fruit safe by using this method. In addition, quality properties, such as color, which is effective on the consumer preference also, protected better by the effect of volumetric heating.

关键词： Probiotics  

摘要： In the present study, physicochemical, microbial, and rheological attributes of Synbiotic set bio-yogurt samples affected by Lactobacillus acidophilus LA-5, honey, and aqueous cinnamon extract were evaluated which stored at 4 celcius for 15. Yogurt samples prepared with lower levels of flavors (honey and aqueous cinnamon extract) indicated a lower pH (<3.5) and water holding capacity (WHC), and also the higher acidity (12-14D), syneresis, and dry matter (DM) along with cold storage. Because of the acidification process, L* value was decreased whereas a* and b* values increased in all samples. During the storage, time affected pH, titrable acidity, syneresis, WHC, however, complex viscosity, probiotics' survival, dry matter, L*, a*, and b* values were found to be insignificant (p > .05). Practical applications Results of rheological evaluation expressed that raising the levels of additives facilitated the set yogurt to form weak complex viscosity, in which cinnamon had superior influence compared to honey during the fermentation process and storage. In addition, the results of microbial measurements indicated that honey and aqueous cinnamon extract did not reduce the survival of probiotic (L. acidophilus LA-5) during storage time.

关键词： Starch   Gelatin   Beeswax   Bloom value   Extrusion blowing  

摘要： The effects of various Bloom values (120, 160, 200, 230, and 250) of gelatins on the properties of starch/gelatin-beeswax (S/G-BW) films fabricated by extrusion blowing were investigated. The S/230G-BW blend exhibited the highest storage modulus and complex viscosity determined by rheological analysis. The results of dynamic mechanical analysis and scanning electron microscopy images demonstrated that starch granules could be more effectively melted and fractured in the composite films with higher Bloom values. Attenuated total reflectance-Fourier transform infrared and X-ray diffraction spectra revealed that gelatin Bloom values strongly affected the migration and crystalline properties of beeswax in the film matrix, while the S/230G-BW film had more triple helical structures, as shown by the results of circular dichroism analysis. In addition, lower water solubility and higher thermal stability of the produced films was obtained from the gelatins with higher Bloom values. The highest water contact angle (87 degrees) of the outer film surface and lowest water vapor permeability (0.88 x 10(-10) g m(-l) .s(-1) .Pa-1) were obtained for the S/200G-BW sample. The S/230G-BW film had the maximum values of tensile strength, elongation at break, and Young's modulus that exceeded those of the S/120G-BW film by 90.9%, 96.8%, and 102.4%, respectively. Finally, the extremely high Bloom values enhanced the interfacial interactions between the starch and gelatin components in the films, which negatively affected their performance. Hence, the gelatins with an appropriate Bloom values could be used to produce S/G-BW films with desirable physicochemical properties.

关键词： Nanoparticles  

摘要： The therapeutic properties of clove oil are well known, however, the pungent nature, chemical instability, and low water solubility impose limitations in harnessing its potential. Nanoemulsion of clove oil (CON) was prepared to overcome the above constraints. The non-ionic surfactants Tween 20, 40, and 80 with hydrophile lipophile balance (HLB) of 16.7, 15.6, and 15, respectively, were used to stabilize CON. The creaming index of CON prepared with Tween 20, 40, and 80 was 22.75, 17.5, and 1.5%, respectively, after 8 days of storage at room temperature. Tween 20 and 40 produced particles >300 nm while Tween 80 produced similar to 150 nm. Transmission electron microscopic image of spray-dried CON (with Tween 80) showed particles in the range of 150-190 nm. The in vitro release studies showed 76 and 42% cumulative release of CON and native clove oil (NC), respectively, at pH 7.4. The cellular toxicity of CON was significantly reduced by fourfold compared to NC at a concentration of 60 mu g/ml when tested on CaCO2 cells. Similarly, hemolytic activity on red blood cells revealed less than 10% hemolysis. In addition, CON also exhibited higher in-vitro antioxidant compared to NC as shown by 1, 1-diphenylpicrylhydrazyl and 2,2 '-azino-di-[3-ethylbenzthiazoline sulfonate (6)] (ABTS) radical scavenging activity. Practical application: The study highlights the development of clove oil nanoemulsion using cost-effective, commercially important polysaccharide (maltodextrin) and surfactant for increased bioactivity. The spray-dried nanoparticle showed high retention (95%) of oil and small particle size even after 1 month of storage at room temperature. The biological studies signify the compatibility of nanoparticle for its nutraceutical applications because of its low cytotoxicity (fourfold reduction), hemolytic activity, and high anti-oxidant property. The clove oil nanoparticles can replace the clove oil/microencapsulated particles in food product development due to their high