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关键词： Water temperature  

摘要： The objective of the research was to study the effect of feed concentration and water temperature on physicochemical, chlorophylls, and antioxidative properties of Pandanus amaryllifolius leaf extract. The experiment was designed as 2(2) factorials with three center points. The effect of two main dependent variables, pandan solid-based feed (35, 50 and 65 g pandan leaf/100 g water) and water temperatures (25, 60 and 95 celcius), and co-factors were considered through their impact on some important properties of the extract. An increasing of solid-based feed resulted in increased total soluble solids, lightness (L*), chlorophyll a, chlorophyll b, total chlorophyll, total phenolic, and antioxidant activity (DPPH) of the pandan extract (p < .05). In addition, the water temperature affected the lightness (L*), total phenolic, and DPPH of the extract. At higher temperature of water extraction, these values increased significantly (p < .05). An excellent relationship between antioxidative properties and chlorophyll contents was also found (R-2 > .950). Novelty impact statement The extraction conditions significantly affected the properties of the aqueous pandan leaf extract. The pandan leaf extracted with high solid-based feed concentration (65/100 g water) at water temperature of 95 celcius could be used as a potential natural coloring agent exhibited promising antioxidant potential for food product applications.

关键词： Mimosa scabrella Bentham   Phenolic compounds   Mineral   Identity and quality parameters   Antibacterial activity   Antioxidant activity  

摘要： Bracatinga (Mimosa scabrella Bentham) honeydew honey is a Brazilian dark honey in increasing international appreciation. In this sense, the knowledge of its composition and potential biological properties becomes indispensable. In the present study, the physicochemical characteristics, including mineral and phenolic composition, and the scavenging, reducing, and antimicrobial proprieties of bracatinga honeydew honey (bhh) from five different geographical locations, were investigated. Bhh proved to be a potential functional food due to its high content of minerals (up to 6395 mg kg(-1)) and phenolic compounds (up to 2393 mu g 100 g(-1)) and high scavenging and reducing activities. High antimicrobial activity against four bacterial strains, with minimum inhibitory concentration values ranging from 10 to 60%, were also found. Additionally, through principal component analysis, partial discrimination of bhh was observed according to the geographical location, which favored the separation of samples from Lages, and mainly due to the presence of nectar in this honey, which was proposed for the samples from Bom Retiro.

关键词： Pyrodextrins   Viscosity   Molecular weight  

摘要： The traditional sorghum beer brewed by African communities differs from the traditional beer obtained from barley, mainly in the absence of hops and in a higher acidity level. People diagnosed with celiac disease find it as an alternative option when enjoying a good beer;however, some of the technological differences could be improved with the use of pyrodextrins obtained from the same cereal. In this work the use of pyrodextrins obtained by a treatment at 120 degrees C with acid during 360 min is proposed. A composite central design was made varying the concentration of pyrodextrins between 5 and 15 g/L and hop between 30 and 60 mg/L. The results indicate that the use of pyrodextrins up to a concentration of 10 g/L improves alpha-acid utilisation, bitterness and viscosity of the drink, achieving values similar to a typical lager beer obtained from barley. For 10 g/L pyrodextrin addition the increase in the wort and beer viscosity was 4.4% and 4.9%, respectively.

关键词： amylopectin   amylose   Oryza sativa   pasting properties   pigmented rice   starch hydrolysis  

摘要： Background and objectives Some factors related to rice processing, composition, and grain microstructure may interfere with starch digestibility. The objective of this work was to evaluate the impact of physicochemical properties and rice processing on the starch digestibility of genotypes produced in Brazil. Five traditional white rice genotypes, one black rice, and one red rice genotype were studied. The traditional white rice genotypes were evaluated as brown rice as well as in the polished rice form, while both black and red rice were evaluated in the unpolished form. Findings The digestibility ranged from 41.40% to 99.81%, being positively correlated with starch content and peak viscosity and negatively correlated with pasting temperature. The unpolished rice group exhibited lower digestibility value than the polished rice group as a result of the presence of bran. Low amylose cultivars had higher starch hydrolysis percentage. Conclusions The type of processing influenced the starch digestibility profile, in which the presence of bran and pigments in whole rice reduce starch hydrolysis percentage. The extent of gelatinization of the starch, identified through the peak viscosity and the pasting temperature of RVA, also had a direct influence on digestibility. Significance and novelty For the first time, different types and processing of Brazilian rice genotypes have been studied about the starch viscosity and digestibility profiles and related to other quality traits, what can drive consumption of a greater diversity of rice according to different market demands and energy needs.

关键词： Dry powder inhaler   Surface properties   Surface characterization technology   Pulmonary drug delivery   Stability  

摘要： Background Dry powder inhaler (DPI) formulations are highly efficient in pulmonary drug delivery because devices for their delivery are portable and aerosolization does not require a propellant. The performance of DPIs depends on various physical properties of particles for their manufacture, including aerodynamic diameter, density, particle shape, surface composition, morphology, roughness, and energy. Among these, particle surface properties are the most important factors in determining the interparticulate interactions, which affect the aerosolization efficiency, physicochemical stability, and subsequent in vivo lung deposition efficiency. Area covered For a better understanding of the correlation between surface properties and the performance of DPI, there is the need to perform surface characterization of the DPI. This review focuses on analysis of the technology used in the design of DPIs. Thus, the surface crystallinity and polymorphism, surface energy, surface roughness, and changes in solid-state properties of the particles used in DPI formulation will be determined. Expert opinion The commonly used solid-state techniques may not be appropriate for the characterization of DPIs because their detection is mainly limited to the fine changes in physicochemical surface properties such as partial amorphous contents generated on the drug particle surface. Thus, sophisticated technologies with higher detection limits and superior spatial resolutions are required for in-depth characterization. Data obtained from surface analytical techniques can lead to an in-depth understanding of inhalable dry powder at the particle surface. This can provide unique predictive insights into rationally designing inhalable particles with optimal surface properties to provide optimal aerosolization performance for a given DPI formulation.

关键词： Avocado seed   Food applications   Nutraceutical compounds   Physicochemical properties   By-products use  

摘要： Vegetal wastes are currently a source of pollution due to the excess of organic compounds in the environment. Seeds are the main by-product of the avocado industry and represent 16-22% of the total weight and it is considered a waste without applications. Despite the seed stands out for its high content of phenolic compounds, lack of knowledge regarding of the best processing state using non-invasive and short-time methods are required to take advantage of these nutraceutical compounds. This research aimed to find correlations from physicochemical analysis, color, hardness, and firmness of the whole avocado seeds with its nutraceutical properties as long as the ripeness increased, providing information for further industrial use of this waste. The results indicated that 'Hass' avocado fruit ripening positively correlates with the improvement of the physicochemical parameters involved in the fruit processing and the increase of nutraceutical compounds in the seed. The ripeness process decreased moisture (%) and hardness (N) parameters in the seeds (27.69 and 16.4%, respectively), facilitating its processing. Moreover, the ripening increased the antioxidant capacity by DPPH* around 7%, due to the concentration of phenolic compounds in the seed. Seed's phenolic compounds were positively correlated with the Hue angle at increasing ripeness, becoming a potential physicochemical indicator for the industry. The prediction of changes in nutraceutical compounds and physicochemical properties, as ripening occurred, may reduce analysis times, processes, and guidance to use avocado seeds as a by-product. These results facilitate the seed processing and open up opportunities for its use in the industry.

关键词： Physicochemical properties  

摘要： Jaban watermelon seeds are one of the most favorable nuts in Iran. The production of these popular nuts leaves a large amount of environmental pollutants. The aim of this study was to evaluate the rheological, physicochemical, and sensorial properties of ice cream by replacement of milk cream with watermelon exocarp powder (WEP) at 0%, 20%, 40%, 60%, 80%, and 100% levels. The results showed that although all samples showed the pseudo-plastic behavior rheologically, the replacement of cream with WEP significantly affected the physicochemical properties. Adding the WEP increased the textural properties and melting resistance of the samples, whereas overrun, draw temperature, and the flow behavior index decreased, significantly (p < 0.5). Hedonic evaluation showed not only that adding the WEP at 20% level does not have a significant effect on sensory properties, but also received the highest scores. Finally, regarding the high amount of fiber and minerals in WEP can lead to produce lower calorie ice cream with higher nutritional value. Novelty impact statement A new look on using Jaban watermelon environmental pollutants to produce economically and nutritionally valuable by-products. Investigation of macro- and micro compounds in watermelon exocarp powder. Producing of low calorie and high nutritional value ice cream by replacing cream with WEP.

关键词： Quinoa   Wheat   Dietary fiber   Physicochemical properties   Functional properties  

摘要： Soluble and insoluble dietary fiber (SDF and IDF) were extracted from quinoa and wheat. Results showed that all the dietary fiber (DF) samples exhibited typical infrared spectrum characteristics of polysaccharides. Compared with wheat soluble dietary fiber (WHSDF), quinoa soluble dietary fiber (QU(SDF)) displayed a compact structure, higher reducing power and digestive enzyme inhibitory activity. WHSDF showed stronger DPPH radical scavenging activity than QU(SDF). Quinoa insoluble dietary fiber (QU(IDF)) and wheat insoluble dietary fiber (WHIDF) displayed similar network structure, but the alpha-glucosidase inhibitory activity of WHIDF was higher than QU(IDF). Moreover, the bound polyphenols in QU(IDF) and WHIDF also showed better DPPH radical scavenging activity and alpha-amylase inhibitory activity. In summary, the DF of quinoa and wheat showed different structural, physico-chemical and functional properties, and in both samples bound polyphenols had significant contributions to the antioxidant and hypoglycemic capacity of IDF.

关键词： amylopectin   molecular weight   starch granules   sweet-waxy maize  

摘要： Sweet-waxy maize is a special type of maize with recessive mutations of waxy gene and a gene disturbed sugar-starch transition, and its starch is composed of nearly pure amylopectin. The starch physicochemical properties of four inbred lines and six hybrids of sweet-waxy maize are studied. The starch granules are irregular and large in hybrids and oval and small in inbred lines. The chain length, molecular weight, and crystallinity are significantly different among the samples. However, no distinct difference is observed between hybrids and inbred lines. The branching degree of hybrids (except THN2000) is significantly higher than that of inbred lines. The pasting, gelatinization, retrogradation temperatures, peak and breakdown viscosities, retrogradation enthalpy, and percentage are lower in inbred lines than in hybrids. By contrast, trough, final, and setback viscosities and gelatinization enthalpy are indistinctly different between the hybrids and inbred lines. Among the six hybrids, HTN2 is suitable to make glutinous food due to its high viscosity, whereas MTN2 may enable the production of food with minimal retrogradation. The high viscosity of JH1501 and the low retrogradation percentage of JSW15525 among the four inbred lines endow different advantages on quality breeding.

关键词： Wood   Wood drying   Microstructure   Density   Porosity   Decomposition process  

摘要： The influence of drying on the microstructure, physical and chemical properties of some tropical wood species has been investigated using thermogravimetric analysis, differential scanning calorimetric (DSC), FTIR-ATR spectroscopy, mercury intrusion porosimetry (MIP) and environmental scanning electron microscopy (ESEM) analysis. Eleven tropical species were used in this study. Results showed that the common Cameroonian wood species can be grouped into three classes: Ga (lightwood) with cross-linking fibers having high volume of macropores, density in the range 0.2-0.4 g cm(-3)and high lignin content;Gb (medium dense) with unidirectional fibers packing, density around 0.6 g cm(-3)and Gc group showing high densification of unidirectional fibers and low porosity justifying the density > 0.8 g cm(-3). Both the Gb an Gc groups have less significant lignin content. A relatively high rate of drying for Ga with respect to low drying rate for Gc was observed in direct relation with their porosity of similar to 72 Vol% and similar to 36 Vol%, respectively. LTF and WG showed similar cumulative pore volume (0.44 mL g(-1)) with different pore size distribution: 28% and 22% of macropores, 39% and 60% of mesopores and 33% and 18% micropores, respectively. Thermal analysis revealed that lightwoods have the highest amounts of residues and lower thermal stability of chemical components than dense woods. It has been found that the degradation process of hemicellulose, cellulose and lignin occurs mainly at about 200-300 degrees C, 300-350 degrees C and 350-500 degrees C, respectively. The group Ga with low drying rate, a low cycle of reproduction, a high volume of porosity together with large pore sizes appeared promising candidates for the design of ecological, environmental and sustainable management policy of wood transformation in developing countries and even worldwide.