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关键词： baked   imbibition   oat   viscosity   water absorption capacity  

摘要： Background and objectives Oat (Avena sativaL.) consumption has increased mainly due to the health benefits as this cereal is an excellent source of prebiotics and high-nutritional compounds. In this work, an imbibition treatment was applied to improve the physicochemical properties of baked oat (Avena sativaL.) grains. Findings Studied samples included flour from the grains imbibed, dried and baked at 120 degrees C for 30 min (IT120), flour from grains without imbibition and baked at 120 degrees C for 30 min (T120) and flour from raw grains (R). The protein and crude fiber content did not change with the treatments, but the lipids content decreased. The water absorption capacity (WAC) increased 1.14- and 2.6-folds for T120 and IT120, respectively, when compared to R. The rheological analysis demonstrated an important effect of the concentration and the imbibition processes as the viscosity values increased sixfold in IT120 at 30% solids content. Conclusions The imbibition and baking treatment of whole oat grains resulted in structural rearrangements changing the physicochemical properties which could be useful when using these flours as an ingredient. Significance and novelty The structural modification promoted by the imbibition and baking treatment could increase the potential applications of oat flour.

关键词： Physicochemical properties  

摘要： This study aimed to produce burgers using fructooligosaccharides (FOS) as a substitute for animal fat. Four treatments (T1-control;T2-with 50% fat reduction;T3-with 50% fat reduction + 5% FOS;T4-with 50% fat reduction + 10% FOS) were produced. For the proximate composition, T4 had the lowest moisture. For lipids, the fat reduced treatments (T2, T3, and T4) differed of T1. For lipid oxidation, T3 and T4 had highest (p < .05) values than T1. For the cooking characteristics, T4 had the highest yield and the lowest cooking loss. Before cooking, the redness of T3 differed from the other treatments. After cooking, the burgers of T4 had lower lightness than those of T1. Although flavor acceptance and overall liking reduced with the FOS, the scores remained within the acceptance region. Therefore, FOS is an alternative for the fat replacement in burgers. Practical applications Beef burgers are widely consumed by practicality. However, these products have high fat content. Thus, the reduction of this constituent is a challenge for meat industry because it is responsible for functional and palatability characteristics. Therefore, this study aimed to develop low-fat beef burgers containing fructooligosaccharides and to evaluate the effects on physicochemical characteristics, cooking quality, and sensory evaluation. Moreover, the present study used the Principal Component Analysis and the penalty analysis for better visualization and interpretation of sensory attributes.

关键词： sturgeon fillet   low temperature vacuum heating   physicochemical characteristics   protein oxidation   lipid oxidation  

摘要： BACKGROUND Sturgeon is popular for its nutritious value and its taste. However, sturgeon fillets are traditionally heated in 100 degrees C boiling water, resulting in unfavorable taste and with a negative effect on the quality. This study considered the effect of combinations of vacuum and low-temperature treatments (LTVH groups) on sturgeon fillets compared with the traditional heat treatment (TC groups). RESULTS The results show that the LTVH groups had lower cooking-loss rates. All LTVH fillets were changed to a white color, and appeared 'done', as did the TC fillets. The LTVH and TC methods gave rise to significant differences in texture: the springiness of the LTVH groups decreased with heating time, and decreased rapidly in the TC groups (P < 0.05);hardness and chewiness increased with time and temperature in the LTVH groups, but decreased in the TC groups. More compact and denser gaps were observed in LTVH70 groups and TC groups. Less protein and lipid oxidation was evident in LTVH groups, including more myofibril protein solubility;there was less protein aggregation, fewer thiobarbituric acid reactive substance, and Schiff base. CONCLUSION Vacuum and low-temperature treated sturgeon fillets can be served as a good alternative. This treatment caused slight tissue damage and less proteolysis and lipid oxidation, which is beneficial for the quality of aquatic products.

关键词： ChitosanBombyx mori   Hydroxyapatite   Composite   Nanostructure   Osteoporosis  

摘要： Composites of chitosanBombyx moriwith hydroxyapatite - (Ca-10(PO4)(6)(OH)(2)) were obtained and their interaction in aqueous solutions was studied. The composition and structure of composites obtained at various mass ratios were studied. The possibility of controlling the composition and morphology of composites by varying the ratios of the initial reagents was shown. FITR and UV spectroscopic methods were used to investigate the structure of composites. The results of XRDA studies have shown that depending on the CS/HA ratio, CS/HA crystals with sizes from 6.9 to 20.4 nm were formed in the system. Using the methods of potentiometry, conductometry and viscometric measurements the equivalent composition of the composite was determined, which is CS/HA-70:30 mass %. It was found that nanostructured composites with minimum sizes from 2 to 15 nm were obtained under the selected synthesis conditions. The obtained data are applied interest for the prevention and treatment of osteomolyosis, osteoporosis and bone replacement of living organisms.

关键词： Maple syrup   Physicochemical composition   Brix   Sugars   Phenolic compounds   Minerals   Seasonal changes   Nova Scotia  

摘要： Maple syrup is produced by concentrating the maple tree sap. The physicochemical profile of maple syrup can be varied depending on the processing method, microbial contamination, seasonal and geographical variations etc. Apart from being a better alternative to refined sugar, the minerals and phenolics in maple syrup may provide additional health benefits owing to their bioactivities. We studied the physicochemical profiles of maple syrup samples from North America and the seasonal compositional changes of the syrup from Nova Scotia (NS). Syrup pH, color, Brix were significantly differ depending on the location. Brix values ranged from 61.6 to 70.2 degrees. Thirteen different phenolics including protocatechuic acid, coniferyl alcohol, vanillin, and syringic aldehyde were identified and quantified. The total mineral content ranged from 2.6 to 4.8 g/L of syrup. Potassium was the most abundant, followed by calcium, magnesium, phosphorus, manganese, and zinc. Analyses of NS syrup during early, mid and late seasons revealed that, total phenolics and minerals increased and the syrup color became darker towards late season. Syrup pH, brix and sugars did not differ among the seasons. Interestingly, vanillin, syringic acid and syringic aldehyde were the main phenolics in early maple syrup samples while protecatechuic acid was the predominant in late season.

关键词： bioactive compounds   food processing   food waste reduction   functional food   mango kernel oil   polyphenols  

摘要： Mango (Mangifera indicaL.) is a fruit plant of family Anacardiaceae, widely grown all over the world, and is a very popular fruit in the world market. Mango fruit is the second most traded tropical fruit and fifth in terms of production globally. Large quantities of mango processing coproducts are generated (peels and seeds), which usually are discarded as waste, yet are a potential source of fat, protein, carbohydrate, and certain bioactive compounds. Mango kernel is a remarkably rich source of macronutrients and micronutrients including calcium, potassium, magnesium, phosphorus, and vitamins A, E, K, and C. Phytochemicals with a notable therapeutic potential such as tocopherols, phytosterols, carotenoids, polyphenols (gallotannins, flavonols, benzophenone derivatives, mangiferin, homomangiferin, isomangiferin, anthocyanins, kaempferol, and quercetin), and phenolic acids (4-caffeoylquinic acids, caffeic, coumaric, ellagic, gallic, and ferulic acid) are reported. The phytochemicals have high antioxidant, antimicrobial, anticancer, and, antiproliferation activities and could be used for food, cosmetic, and pharmaceutical applications. The nutritional composition of mango kernel constitutes 32.34% to 76.81% carbohydrate, 6% to 15.2% fat, 6.36% to 10.02% protein, 0.26% to 4.69% crude fiber, and 1.46% to 3.71% ash on a dry weight basis. The nutritional profile of the kernel suggests its usability as a food ingredient in the development of value-added products such as mango kernel oil, mango kernel butter, mango kernel flour, and biofilms among other diverse products. This comprehensive systematic review explores mango kernel as a potential and novel food ingredient to meet the needs of a health-conscious population. The review also provides a remedy to waste management and environmental pollution.

关键词： contact guidance   freeze-cast   release   scaf-folds   tissue engineering  

摘要： In this study, retinoic acid loaded-PLGA-gelatin matrixes were prepared with both freeze-casting and freeze-drying techniques. Herein, the effect of unidirectional microstructure with tunable pores on release profile, cellular adhesion, migration, and differentiation was compared. Morphological observation determined that highly interconnected porous structure can be formed, but lamellar pore channels were observed in freeze-casting prepared constructs. The absorption ratio was increased, and the biodegradation rate was decreased as a function of the orientation of microstructure. The in-vitro release study illustrated non-Fickian release mechanism in both methods, so that erosion has predominated over diffusion. Accordingly, PLGA-gelatin scaffolds prepared with freeze-drying technique showed no adequate erosion due to the rigid structure, while freeze-casting one presented more favorable erosion. Microscopic observations of adhered P19 embryonic cells on the scaffolds showed that the freeze-casting matrixes with unidirectional pores provide a more compatible microenvironment for cell attachments and spreading. Besides, it facilitated cell migration and penetration inside the structure and may act as guidance for neuron growth. Improvement in the expression of neural genes in unidirectionally oriented pores proved the decisive role of contact guidance for nerve healing. It seems that the freeze-cast PLGA- gelatin-retinoic acid scaffolds have initial features for nerve tissue regeneration studies.

关键词： Optical materials   Crystal growth   X-ray diffraction   Nonlinear absorption   Z-scan   Optical limiting  

摘要： Herein we report the tunable optical limiting property of a metal-organic cesium tetroxalate dihydrate (CTD) complex. Temperature and pH were optimized to be 40 degrees C and 3.5 respectively to grow CTD single crystal using the solvent evaporation method. The compound formation was confirmed by its response to single crystal and powder x-ray diffraction analysis. Thermal, mechanical, dielectric, linear optical, photoconductivity and photoluminescence properties of title crystal are reported. Nonlinear coupling between delocalized pi-electrons of metal-ligand interaction and the oscillating electric field of a laser beam enhanced the nonlinear optical parameters. The third order nonlinear refractive index (n(2)), absorption coefficient (beta) and susceptibility (chi((3))) of CTD complex under continuous-wave laser excitation are found to be (3.26 +/- 0.033) x 10(-8) cm(2) W-1, (10.33 +/- 0.41) x 10(-4) cmW(-1) and (8.98 +/- 0.35) x 10(-5) esu respectively. Variation in two-photon absorption (2PA) coefficient measured under nanosecond pulsed laser excitation of different intensities confirmed the presence of sequential 2PA in CTD complex. The optical limiting threshold was investigated under different intensities were found to vary from (1.09 +/- 0.05) x 10(12) Wm(-2) to (2.49 +/- 0.05) x 10(12) Wm(-2) showing the intensity tunable optical limiting property of CTD material.

关键词： Egg yolk   Phosphorylation   Succinylation   Emulsification   Gelation  

摘要： This study aimed to verify influence of sodium tripolyphosphate and succinic anhydride on functional characteristics of egg yolk (EY). Addition of the two salts led to modification of yolk protein, and modification degree improved with increasing reaction time. Two modification methods caused a two-to three-fold enhancement in emulsion stability of EY. The hardness of yolk gels was effectively increased by 29.73% or 56.61%. The improved emulsion stability and gelling properties of the modified EY resulted from changed structures of EY protein. Physicochemical properties, such as increased solubility as well as decreased surface hydrophobicity, particle size of yolk granules, and zeta potential, contributed to the enhanced functional properties. The result of scanning electron microscopy revealed that modification was beneficial in forming fine and compact EY gel network. The gel strength and water-holding capability of the yolk gels were thus considerably increased.

关键词： Folic acid   Gastrointestinal-resistant composite   Controlled release   Alginate   Pectin  

摘要： Potential effects of folates on the treatment of several human diseases like cognitive function, neural tube defects, coronary heart disease and certain kinds of cancers have been discovered. However, the stability of folic acid against adverse conditions is a great concern. The present study investigates various alginate (A)-pectin (P) gastrointestinal-resistant hydrogel to immobilize folic acid. This involves evaluating different compositions of alginate-pectin to achieve higher encapsulation efficiency and stability during simulated gastric (SG) and simulated intestinal (SI) conditions. Coated alginate hydrogels with pectin resulted significant (p < 0.05) better protection of folic acid compared to non-coated alginate hydrogel when exposed to SG condition and when exposed to SI condition, sustained release behavior obtained with the ratio of A70-P30. The structural and physicochemical properties of blended A-P hydrogel were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffractometer, indicating the presence of folic acid into the matrix and signified no covalent reaction between components. Therefore, this adequate composition of alginate-pectin showed to be a potential carrier for folic acid stability.