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关键词： Tannins  

摘要： Tortilla chips made with mixtures of white sorghum and corn were compared with two commercial products made from corn to determine their physicochemical, sensory characteristics, and acceptance. A higher content of white sorghum generated products with dark-red tones, but which were equally fracturable and exhibited the same hardness, when compared to commercial tortilla chips. The total phenolic content ranged from 50 to 75 mg(GAE)/100g, and the condensed tannins content was higher as the white sorghum content in products increased (559-1,100 mu g(CE)/g), but there was no difference in the antioxidant activity (900-1,250 mu M-AEAA/g) among the products. Two groups of consumers who were identified rated commercial products best for overall liking, although Group 1 (n = 102 subjects) rated products made entirely with sorghum as second best, and Group 2 (n = 116 subjects) considered that treatment as the worst. The white sorghum content in products did not affect taste and aroma, but affected its appearance and acceptance for some consumers. Practical applications Tortilla chips are snacks that are widely consumed around the world. Developing foods with health potential to consumers are a current trend in the market. Sorghum grains contain compounds that could provide health benefits, although its tannins content could impart negative visual or astringent effects to products made from them. Tortilla chips made entirely with white sorghum contain a higher amount of condensed tannins than products made with corn, these modifies the appearance of chips affecting the liking of consumers. Despite this, a segment of consumers considered that those products were almost as good as commercial corn made tortilla chips.

关键词： Physicochemical properties  

摘要： Amaranth is an underutilized pseudocereal highly valued for nutritional composition. In this study, the effects of processing (soaking, boiling, and autoclaving) on the physicochemical properties on flour fromAmaranthus cruentuswere determined by conducting various analyses for effective ingredient applications across various food products. The amaranth flour was defatted with n-hexane in order to improve protein availability since fat forms lipid complexes with macro and micronutrients. Results showed that processing varied with regard to the impact it had on the properties of the flour. Boiling and autoclaving reduced the ash and protein content;however, the decrease in the protein content (14.23%-15.05%) was deemed insignificant. Moreover, processing treatments resulted in an increase in properties such as water absorption capacity, and in vitro digestibility (67.12%-69.71%) which is beneficial in baked products. Practical applications The physicochemical properties of the flour from amaranth seeds were impacted by processing with some of these changes being positive such as for the in vitro protein digestibility. The amaranth flour can be used to fortify other flours in order to obtain a desired product as well as to complement other food to increase the biological/nutrient value of processed food products.

关键词： Hippophae rhamnoidesL   inulin   maltodextrin   spray drying   freeze drying   vacuum drying   flavonols   HMF  

摘要： Sea buckthorn (Hippophae rhamnoidesL.) juice with inulin, maltodextrin, and inulin:maltodextrin (1:2 and 2:1) were spray-, freeze- and vacuum-dried at 50, 70 and 90 degrees C. The study aimed to assess the impact of drying methods and carrier agents on physical properties (moisture content, water activity, true and bulk density, porosity, color parameters, browning index), chemical components (hydroxymethylfurfural and phenolic compounds) and antioxidant capacity of sea buckthorn juice powders. Storage of powders was carried out for six months. Inulin caused stronger water retention in powders than maltodextrin. Vacuum drying provided powders with the highest bulk density. Maltodextrin did not promote browning and HMF formation as strongly as inulin. More phenolic compounds were found in powders with maltodextrin. Storage increased the antioxidant capacity of powders. The results obtained will be useful in optimizing the powders production on an industrial scale, designing attractive food ingredients.

关键词： Pseudocereal   Solubility   Emulsifying properties   High-intensity ultrasound  

摘要： The present study investigated the effects of high-intensity ultrasound (HIUS) on the physicochemical and functional properties of amaranth protein isolates (API). Aqueous dispersions of API (10%) were continuously treated for 15 or 30 min with ultrasound equipment (100 W, 30 kHz) at 30, 60, and 90% amplitudes. The electrophoresis technique demonstrated no changes in the molar masses of the proteins. However, HIUS significantly increased the surface free sulfhydryl groups (SH) and changed the surface hydrophobicity, indicating a breakdown of internal links that maintained the native API structure. Ultrasound reduced the size of the particles in the aqueous dispersions of API, suggesting the dissociation of aggregates from API. The results showed that the solubility in most HIUS-treated API was significantly (p < 0.05) higher than that of the native proteins at pH 7. The energy density of 50 J/cm(3) provided the best-combined properties of emulsion formation and stability. These results suggest that HIUS is a useful technology to improve the functional properties of amaranth proteins.

关键词： Bone mineral density   Bone microstructure   Bone mineral content   Single X-ray system   Calcium depletion   Trabecular and cortical bone  

摘要： This study evaluates the effect of three calcium levels in the diet (normal, moderate, and severe calcium depletion) on bone metabolism of male Wistar rats during their growth period. Bone mineral density (BMD) and femur length were determined in vivo during the growth stage using a single X-ray transmission system. The apparent calcium absorption was calculated in the rat adolescent and adulthood stages. At the end of the experiment, calcium concentrations in serum and urine were analyzed. The bones were evaluated postmortem to corroborate in vivo analyses. Microstructural properties of cortical and trabecular tissues of femurs bones were assessed using scanning electron microscopy. Bone mineral contents (Mg, Ca, P, and K) were quantified by inductively coupled plasma. Severe calcium depletion in the diets in the development stage affects the bone quality parameters such as bone mineral density and mineral content. Moreover, it was found thinner cortical and trabecular bone areas. Additionally, it was found that severe calcium depletion increased the apparent absorption of calcium as a defense mechanism, but with the decrease of the BMD peak, and the thickness of cortical bone as well as trabecular bone porosity. The severe calcium depletion increased the efficiency of apparent absorption calcium as a defense mechanism, but, even so, decreases the BMD peak as well as the thickness of cortical bone and trabecular bone porosity.

关键词： Ascorbic acid  

摘要： Minimally processed carrots (MPC) was coated with ascorbic acid-added carboxymethyl cellulose/candelilla wax emulsion, then placed in plastic boxes with perforated polyethylene wrap, and stored at 5 degrees C. It was found that the horizontal cross-section of samples absorbed larger amounts of emulsion than the lateral surface. The individual wax globules of the coating deposited in the interior of the damaged (by peeling) cortical cells were visualized using scanning electron microscopy. The coating improved water vapor resistance of MPC, temporarily increased the respiratory rate, decreased the activity of polyphenol oxidase, and prevented the formation of "white blush." The acidity, total phenolic content, and texture of the MPC were not affected by the coating treatment. In summary, the edible coating (along with packaging) can serve as a promising approach for maintaining the fresh-like characteristics of minimally processed carrots through 21 days of cold storage. Practical applications The treatment of minimally processed carrots with the carboxymethyl cellulose/ candelilla wax/ascorbic acid emulsion results in increased moisture retention. Consequently, the coated carrots exhibit reduced weight loss, unchanged hardness, and no "white blush." As expected, the coating inhibited the activity of polyphenol oxidase, most likely due to the MPC surface acidification. In summary, the edible coating (along with packaging) can serve as a promising approach for maintaining the fresh-like characteristics of minimally processed carrots through 21 days of cold storage. However, the noticeable disadvantage of the coated carrots is the waxy circular deposit around the pericycle and endodermis cells.

关键词： Organogels   Palm olein   Sorbitan monostearate   Soya lecithin   Glyceryl monostearate  

摘要： The objective of this study is to investigate the effects of three different organogelators, sorbitan monostearate (SMS), soya lecithin (SL) and glyceryl monostearate (GMS) prepared at different concentrations (12%, 15% and 18%, w/w) on the structural, thermal and mechanical properties of palm olein (PO)-based organogels. Polarized light microscopy analysis revealed needle-like crystals in SMS-PO, rod-shaped tubules in SL-PO and rosette-like aggregates in GMS-PO organogels. Intermolecular hydrogen bonding and van der Waals forces were the main drivers for the self-aggregation of these organogelators in PO, as observed in Fourier transform infrared (FTIR) spectroscopy. X-ray diffraction (XRD) results indicated beta'-type polymorphic structure in SL-PO and GMS-PO. As the concentration of organogelators increased, there was a corresponding increase in the firmness, gel-sol transition (T-gs) and melting temperatures of the organogels. SMS-PO with amorphous structure had the lowest firmness, thus produced weaker gel with lower thermal stability. The oil binding capacity (OBC) of both SL-PO and GMS-PO were over 90%, significantly higher than that of SMS-PO organogels. These findings indicate that crystallization is the key determinant factor to the final properties of the organogel networks. This is influenced by the molecular structure and the concentration of the organogelators used.

关键词： supported catalysts   platinum   alumina   partial oxidation of hydrocarbons  

摘要： Platinum catalysts supported onto bayerite alumina were synthesized and studied. Alumina of the theta-Al(2)O(3)type, which was prepared from metallic aluminum by an aluminate method, was used as a support, and platinum(IV) nitrate and hydrogen hexachloroplatinate(IV) precursors containing Pt(4+)ions were used for supporting an active component. The catalysts were studied by physicochemical methods such as X-ray phase analysis, X-ray photoelectron spectroscopy, transmission electron microscopy, and ultraviolet-visible diffuse reflection spectroscopy. It was found that platinum occurred in a finely dispersed state in both of the catalysts, and it was uniformly distributed over the support surface. The particle sizes were 2.8 and 0.9 nm in the samples synthesized from platinum(IV) nitrate and hydrogen hexachloroplatinate(IV), respectively. The most uniform surface distribution, high dispersity, and a narrow particle-size distribution were obtained with the use of hydrogen hexachloroplatinate(IV). The catalysts were tested in the partial oxidation of natural gas. The catalyst synthesized using platinum(IV) nitrate afforded an almost thermodynamically equilibrium distribution of the reaction products of partial oxidation at a temperature of 700-800 degrees C.

关键词： Sewer-dosed Fe-Salt   Anaerobic digester   Digestate dewaterability   Physicochemical and morphological properties   Fractal   Rheology  

摘要： Dosing of iron (Fe)-salts in sewers to control odour and corrosion problems have proven to be effective on phosphate and sulfide removal in downstream treatment units. However, the interaction of Fe with sludge may impact the sludge properties during wastewater treatment and sludge digestion. Herein, we investigated the downstream impacts of sewer-dosed Fe-salt on key digestate properties including digestate dewaterability. For this, Fe-salt was dosed to a sewer reactor and resultant iron-rich waste activated sludge (Fe-WAS) was digested in an anaerobic digester (AD) in the experimental line of inte-grated laboratory system running in parallel to a control system. Iron containing and non-iron containing digestates were sourced from the respective AD reactors of experimental and control lines. Results showed improved dewaterability in iron containing digestate than non-iron containing digestate, which was attributed to the variations in key digestate properties. Compared to non-iron containing digestate, iron containing digestate exhibited the decreased contents of bound water, soluble extracellular poly-meric substances (S-EPS), protein, polysaccharide, and monovalent-to-divalent (M+/D++) cations ratio. Likewise, we observed the increased mean particle size (D(v)50) for iron containing digestate than the non-iron containing digestate, but fractal dimension (D-f) values were comparable. Besides, iron containing digestate exhibited a reduced degree of thixotropy, relative sludge network strength, viscosity, yield stress, flow stress, and storage/loss/complex (G/G ''/G*) moduli but increased creep compliance and shear strain (%) than non-iron containing digestate. The combined synergistic effects of such favorable changes amongst the key properties of iron containing digestate, might have been responsible for improving it's dewaterability. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Rice   Extrusion   Proanthocyanidins   Starch digestion  

摘要： To characterize the impact of grape seed proanthocyanidins (GSPAs) on the physicochemical properties and in vitro digestibility of extruded rice, the XRD, RVA, DSC, FT-IR, micro-CT, as well as the in vitro digestion model was applied. Compared with normal rice, the extruded rice with different proportions of GSPAs (0-1.5%) increased the color depth, enhanced the porosity, and changed the semi-crystalline structure of extruded rice from an A-type to a mixture of A- and V-types. The viscosity and thermal properties of extruded rice with GSPAs were also changed noticeably. Additionally, a significantly lower equilibrium hydrolysis and k constant were observed in extruded rice with GSPAs (p < 0.05). Those results indicated that extruded rice with GSPAs could be an attractive approach to produce rice starchy food with low digestibility.