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关键词： anti-wrinkle   ascorbic acid   elasticity   emulgel   HPLC   skin   sodium ascorbyl phosphate  

摘要： Objectives Antioxidant containing cosmeceuticals are commonly prescribed products in treating wrinkles and revitalizing the skin. The aim of this study was the comparative evaluation of physicochemical stability and clinical anti-wrinkle efficacy of transdermal emulgel preparations of sodium ascorbyl phosphate (SAP) and ascorbic acid (AA) on human volunteers. Methods Emulgel preparations containing 5% of (SAP) and or (AA) were prepared. HPLC analysis was performed for stability evaluations. Clinical anti-wrinkle efficacy of the formulations was examined on human healthy volunteers in crow's feet area. Elasticity and digital images were recorded before and after treatment. Results Formulations with added antioxidants and kept in the refrigerator exhibited better stability characteristics. Two-sided blind study and placebo-controlled study showed that both actives were effective in wrinkles depth reduction and also elasticity enhancement but statistically significant difference in the efficacy of the products was not observed. Conclusion Formulations containing (AA) and or (SAP) both improved elasticity and wrinkles of the skin almost by the same extent, and it is necessary to add antioxidant stabilizing agents to both preparations to reach a desired stability.

关键词： microscopy and spectroscopy techniques   cellular architecture   nanoindentation   nanostructure   multivariate analysis   Malus domestica  

摘要： A study of the physicochemical, structural, nanomechanical properties at macro, micro and nanometric scales was carried out to determine which features have the greatest influence on the firmness of selected apple cultivars (Golden Delicious, Granny Smith, Gala and Red Delicious). Physicochemical assays, microscopy techniques, image analysis, nanoindentation and spectroscopy were used to characterize the properties of the four selected apples. The data were analyzed using principal component analysis, Pearson analysis and multiple linear regression to classify apple cultivars. These techniques were also used to identify which physicochemical, micro, and nanostructural as well as nanomechanical features were most associated with apple firmness. This allowed for the creation of a mathematical model (R-2 = 0.97) for the prediction of apple firmness from evaluated variables. It was determined that the cellular architecture, stiffness of cell walls and crystallinity index of cellulose fibers were the most important factors in explaining the variability of firmness in the studied apples. This research provides novel and valuable information for understanding the role of cellular architecture, micro and nanostructure, as well as nanomechanical properties in the firmness of the studied cultivars.

关键词： polymers   atomic oxygen   fluence   ion   rarefied plasma  

摘要： A procedure has been developed for simulating the long-term effect of atomic oxygen (AO) of the Earth's ionosphere on spacecraft polymers in a rarefied plasma flow using Kapton H polyimide as a reference material. The condition for the equivalence of the effect of AO on polymers in the ionosphere and at a test bench is the equality of the mass loss. When Kapton H is bombarded with atomic oxygen ions having energies of 30-80 eV, the mass loss due to chemical etching is two orders of magnitude higher than in the case of kinetic sputtering, and the AO fluence and the acceleration factor of tests on the bench are two orders of magnitude higher than in a 5-eV atomic oxygen beam.

关键词： hot paste viscosity   modified granular starches   potato starches  

摘要： Granular potato starch is modified using the debranching enzyme isoamylase. The modification is performed in aqueous suspension (40% w/w) at 35 degrees C by grading the volume (100, 250, and 400 mu L/50 g of starch, 200 U center dot mL(-1)) of enzyme solution added. The starch products obtained are comprehensively investigated in terms of morphological (scanning electron microscopy), structural (X-ray diffraction), thermal (differential scanning calorimetry), techno-functional (solubility, hot paste viscosity, gel strength), and molecular properties (size exclusion chromatography-multi angle laser light scattering-differential refractive index detection). The granular integrity is basically preserved after modification and a molecular degradation predominantly of the amylopectin by debranching is proved. However, a slight reduction of the weight average molar mass of the amylose fraction is found too. In addition, the intended partial molecular degradation of the starch polysaccharides, the effect of the preparation procedure including washing with ethanol and grinding impacts several starch characteristics conspicuously.

关键词： Egg white   Gelation   Braising   Tea   Illicium verum  

摘要： Tea and illicium verum are the main raw materials of marinated egg, and play an important role in the braising process. In this study, effects of tea and illicium verum braise on the physicochemical characteristics, microstructure, and molecular structure of the heat-induced egg white protein gel were investigated. Results indicated that, with an increased in tea and illicium verum concentration, all of the moisture content, T-2 and pH of tea treated boiled egg (TTBG) and illicium verum treated boiled egg (ITBG) showed a decreased trend. The water holding capacity of TTBG showed an increased first and then remained unchanged, while that of ITBG showed a rapid increased first and then decreased continually. The free sulfhydryl group and the hardness of both TTBG and ITBG showed an increased rapidly, and especially, the hardness of ITBG reached 2161.83 g at last. The surface hydrophobicity of TTBG showed an overall increased trend, while that of ITBG showed a decreased trend with a slight red-shift. Environmental scanning electron microscopy showed that TTBG gradually formed small compact aggregates, while ITBG gradually formed hypertrophy porous aggregates. Fourier transform infrared spectrometry displayed that the intramolecular beta-sheets of both TTBG and ITBG showed a decreased trend, while the intermolecular beta-sheets, alpha-helices, beta-turn and intermolecular antiparallel beta-sheets showed an increased trend. In general, both tea and illicium verum could improve the gel strength of boiled egg, but in a different way, and the effect of illicium verum braise on the strength of enhancing gel was better than that of tea.

关键词： Germination   Flours   Nutritional properties   Physicochemical properties   In vitro digestion characteristics  

摘要： Germination can increase the nutritional quality of flours and change their physicochemical properties. In the present study, waxy and nonwaxy proso millet, common buckwheat and pea were germinated for different duration of time (i.e. 0, 1, 2, 3 and 4 d). Subsequent changes in their nutritional, physicochemical and in vitro digestion characteristics induced by germination were assessed and compared. Overall, germination significantly decreased amylose and starch contents and increased the ?-amylase activity and contents of crude fibre, soluble sugars, free amino acids and bioactive components of the flours, revealing this physically efficient treatment for improving the nutritional richness of flours. Germination also affected the physicochemical properties and in vitro starch digestibility of these four flours, though it had different effects on their protein digestibility. These findings inform the application of germination in generating nutritionally rich flours with altered physicochemical properties.

关键词： Dry-cured ham   Lamb   Colour   Texture   ZnPP   Nitrite elimination   Salt reduction   Predictive microbiology  

摘要： There is a new trend to produce dry-cured ham from lamb in shorter times by boning the ham before salting to later obtain restructured hams that are easier to dry and slice. However, little information about the physico-chemical characteristics of Norwegian Fenalars during the process or the safety implications of their elaboration procedures is reported in the literature. The aim of this study was to characterize the colour, texture and physicochemical properties of restructured Fenalars when using Standard Salting (SS), Salt Reduced (SR) and a Non-Nitrite Salt Reduced (NNSR) treatments. Microbiological safety implications of the elaboration process when using the different salting treatments were also assessed using predictive microbiology. To do so, sixty Fenalars were elaborated using a Standard Salting (SS), a Salt reduced (SR) and a Non-Nitrite Salt Reduced (NNSR) treatments. Physicochemical characterization (instrumental colour and texture and Zinc Protoporphyrin content) was performed at the end of the process using thirty Fenalars. The rest of the Fenalars were used to characterize the product through the elaboration process (pH and aw) for the evaluation of microbiological hazards when using the different salting treatments using predictive microbiology. Results showed a significant increase in softness when reducing salt content and a decrease of redness when no nitrite was used, attributed to the formation of ZnPP content instead of nitrosylmyoglobin. In terms of risk assessment, the decrease of aw through the elaboration process reduced the growth capacity of all the microorganisms evaluated. However, microbiological safety implications in salt reduced Fenalars are important, especially when no nitrite was added, because the considerable increase of growth potential of L. monocytogenes. The increase of growth potential of proteolytic C. botulinum is very little and no relevant effect of nitrite on growth potential of S. aureus was observed. Predictive m

关键词： Ultrasonication   Non-thermal processing   Starch   Food texture   Functional property   Biological activity  

摘要： Background: Polysaccharides as biologically essential macromolecules widely exist in plants, animals, and microorganisms. In food industries, they are often used to change physicochemical and textural properties of food products. Ultrasound processing is increasingly used in the modifications of polysaccharide functionalities. Cavitation induced by ultrasound produces high shear force and temperature, leading to the degradation of polysaccharides. This method can improve physicochemical properties and biological activities of polysaccharides for food applications. Scope and Approach: Recent advances in ultrasound processing on extraction, structures, physicochemical properties, and biological activities of diverse polysaccharides are summarized. Mechanisms of action responsible for the ultrasound effects are discussed. Food applications of polysaccharides affected by ultrasound processing are also reviewed. Research gaps in ultrasound-related studies and applications of polysaccharides are identified. Key Findings and Conclusions: Ultrasound-assisted extraction increased yield and reduced extraction time of polysaccharides from different sources. Structure of polysaccharides was changed after ultrasound processing, leading to the modifications of their physicochemical and biological properties. The extents of these changes were influenced by ultrasound frequency and intensity, processing time, solvent temperature, and polysaccharide source and composition. The ultrasound processing involving polysaccharides has been applied in different areas such as fabricating food emulsions and nanoparticles. Overall, ultrasound technology has great potential to be used in food industries for improved functionalities of polysaccharides.

关键词： Bioenergy   Pelletization   Microscopic techniques   Mechanical durability  

摘要： The worldwide increase in the demand for wood pellets has led to increased interest in the use of biomass feedstock. However, the quality of pellets depends directly on the biomass feedstocks. This paper brings new insights about the influence of lignin distribution, physicochemical characteristics, and microstructure on the quality of pellets. The aim of the study was to characterize the physical, chemical, mechanical and energy properties of pellets produced from Pinus radiata (PR), Eucalyptus nitens (EN), Paulownia elongata x fortune (P), and Miscanthus x giganteus (MG), as well as to use microscopic techniques to examine how lignin distribution influences the mechanical properties. The findings show that the pellets made from PR were more suitable for bioenergy production compared to those produced with EN, P, and MG. Anatomical structure proved to be important in relation to pellet quality. The clear areas on the surface of the pellets presented relationship with the percentage of biomass lignin (which ranged from 26.4 to 34.2%). The P and PR pellets were more durable and had fewer empty spaces be-tween particles. The pellets made from EN, which was the material most difficult to compact, had abundant cracks. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： China Green Food   Apple   Physicochemical quality   Metabolomics  

摘要： The Green Food apple production has increased rapidly in China recently, due to its sustainability and high-quality compared to the conventional apple. The aim of this study was evaluating and comparing physicochemical quality as well as metabolomics of the apples grown in green certified and conventional production systems. The results of physicochemical properties indicated that Green Food apples showed significant superiorities than conventional ones at soluble solids content, firmness and titratable acidity. While, in the vitamin C content comparison, there was no significant difference. Compounds, including several phenolic compounds and fatty acids, were revealed by the untargeted metabolomics as differential markers between apples grown in the two production systems, and could serve as the potential markers for differentiating these two types of apples. Overall, these results of this study could encourage the Green Food apples consumption, promote its production, and will benefit the development of Green Food production and the cleaner agricultural production in China.