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关键词： Pistacia veracv Kerman   Amino acid composition   Fatty acid profile   Minerals   Denaturation protein   Protein structure  

摘要： Pistachio flour obtained from oil industry was nutritionally characterized for use as food ingredient in functional foods. Proximal composition, jointly with mineral content, amino acids and fatty acid profile were studied. In addition, different components present in this food ingredient have been analyzed by attenuated total reflectance Fourier transform infrared spectroscopy and thermal properties of proteins were evaluated by differential scanning calorimetry. This flour presented high mineral content such as potassium, phosphorus, magnesium and calcium. Moreover, high amount of unsaturated fatty acids, mainly oleic and linoleic were found. Secondary structure of proteins mainly was formed by parallel beta-sheet and alpha-helix. In the by-product, pistachio protein is in a native state and is able to be denatured at temperatures higher than 100 degrees C. Therefore, food processing of this ingredient can affect the structure of components.

关键词： Cod proteins   Preheat treatment   Physicochemical properties   Oil-in-water emulsion   Interfacial properties  

摘要： Interests in cod proteins (CPs) in food industry are growing due to their high nutritional attributes and the largest fishing amount worldwide. However, CPs are usually consumed as low value-added products, and limited attention has been paid to their emulsifying properties. In this study, the effects of preheat treatment at different temperatures (70-100 degrees C) and time (5-60 min) on the physicochemical and interfacial properties of CPs were investigated. Results revealed that increasing the preheating temperature and time led to smaller particle size, lower contents of sulfhydryl sites, and higher surface hydrophobicity of CPs. Preheat treatment further significantly increased the ratios of CPs-absorption at the oil-water interface of emulsions that presented smaller droplet size and lower interfacial tension due to promoted surface active properties of CPs. Non-reducing SDS-PAGE showed that CPs at the interface were mainly composed of tropomyosin, actin, as well as disulfide bonds cross-linked moieties, which formed a highly viscoelastic film. The interfacial physical barrier hampered the coalescence of adjacent droplets, as verified by lower creaming index, which demonstrated the enhanced stability of preheated CPs-coated emulsions. The findings expand the application potential of CPs as promising emulsifiers by a straightforward preheat treatment.

关键词： Y zeolite   cracking   rare-earth elements   SiO2   Al2O3   ratio   catalyst   ZSM-5  

摘要： This paper describes the investigation of the individual effects of the introduced quantities of rare-earth elements (REE) and of SiO2/Al2O3 ratio on the physicochemical characteristics (textural properties and acidity) of Y zeolite, as well as on the catalytic activity of petrochemical cracking catalysts based on the zeolites prepared, during the conversion of hydrotreated vacuum gas oil (HTVGO). The amounts of REE oxides and the zeolite SiO2/Al2O3 ratio were quantified independently. An increase in REE oxide content in zeolite reduces its acidity. With an increase in SiO2/Al2O3 ratio at constant REE oxide content, the concentration of acid sites decreases, while the specific surface area and pore volume change only insignificantly. A growth in the REE2O3 content leads to a decline in the olefin yield from HTVGO cracking. Catalytic tests of the prepared catalysts demonstrated that an increase in SiO2/Al2O3 ratio enhances the C-2-C-4 olefin yield from HTVGO cracking as a result of the smaller contribution of hydrogen transfer reactions.

关键词： anthocyanin   labile co‐   products   mango peels   pectin   polyphenols   sequential extraction  

摘要： Three-stage sequential extraction of anthocyanins, polyphenols, and pectin has the potential to enhance the product's functional properties and the economic value of mango (Mangifera indica L.) peels beyond the two-stage processes (anthocyanin-pectin and polyphenol-pectin). A three-stage process was developed by incorporating a polyphenol extraction stage in a sequential process where anthocyanins and pectin were co-extracts. Anthocyanins were extracted first (80% ethanol (EC)/2% acetic acid/25 degrees C/1 h), generating a residue from which polyphenols were extracted (65-85% EC/20-80 min/70 degrees C), based on a full factorial statistical experiment. Pectin was subsequently extracted from the second-stage residues (0.25% ammonium oxalate / oxalic acid / 85 degrees C / 1 h). The economic benefits (net present value (NPV), payback period (PBP), product minimum selling price (PMSP) of the three-stage sequential process (anthocyanin, polyphenol, and pectin) and the two-stage processes (anthocyanin-pectin and polyphenol-pectin) were evaluated over a plant life of 25 years. Polyphenols and pectin from the three-stage process had >65% higher antioxidant capacity and up to 10.4% higher purity, respectively, when compared with those from the two-stage processes. There is also more economic gain from the three-stage process (NPV -$4 31 285, PBP -3 years, PMSP < $10/kg) than the anthocyanin-pectin process (NPV -$3 76 917, PBP -3.22 years, PMSP < $10/kg) and the polyphenol-pectin process (NPV -$235 599, PBP -4.29 years, PMSP < $30/kg). Thus, three-stage sequential extraction is an economic process, which enables the recovery of three value-added food ingredients with improved functional properties from mango peels.(c) 2020 Society of Chemical Industry and John Wiley & Sons, Ltd

关键词： Turanose   Physicochemical property   Functional sweetener   Digestibility   Simulated intestinal fluid  

摘要： Among the structural isomers of sucrose, turanose has been considered as one of good candidates as novel sweetener due to its mild taste, low calorie, and anti-cariogenicity. Here, various physicochemical properties of turanose, such as solubility, temperature and pH stabilities, viscosity, non-enzymatic browning reaction, and dynamic vapor sorption, were investigated by comparing them to those of other commercial sugars. Turanose did not significantly hydrolyze through the simulated digestion tract overall but in the artificial small intestinal environment specifically, turanose degraded by only 18% when sucrose was hydrolyzed by 36% after 4 h. In addition, physicochemical properties of turanose confirmed that it had a potential to replace sucrose due to similar or better product qualities as a food ingredient than other types of sugars with similar chemical structure. Thus, our study suggests that turanose can be applied as a functional sweetener or bulking agent in food processing.

关键词： amylose-lipid complexes   crystallinity   differential scanning calorimetry   pasting  

摘要： The physicochemical and nutritional properties of heat-moisture treated (HMT) maize starch and maize meal with stearic acid (SA) are studied. The addition of SA followed by HMT produces nongelling starch and maize meal porridge with reduced pasting viscosity. Heat-moisture treatment significantly (P <= 0.05) decreases the starch hydrolysis, increases resistant starch, and lowers estimated glycaemic index of both maize meal and maize starch with SA. These changes are due to a more organized crystalline structure between starch polymers and well as the formation of amylose-lipid complexes as shown by differential scanning calorimeter and X-ray diffraction. There seems to be a synergistic effect between HMT and stearic addition as HMT promotes more starch polymer interaction compared to amylose-lipid formation for stearic acid addition. These results suggest that HMT combined with SA can be used to manufacture starch-based functional ingredients and foods with reduced glycaemic index.

关键词： Die design   Milk protein concentrate   Protein-protein interactions   Surface hydrophobicity   Rheological properties  

摘要： Extrusion processing has been used to modify the functional properties of proteins. The protein-protein interactions, surface hydrophobicity, and rheological properties of milk protein concentrate extruded using dies of different geometries (circular, annular and slit) were quantified. With the same extrusion treatment history prior to the die, extrudates generated using dies with higher wall shear (slit 1.4 x 10(4) s(-1) > annular 1.1 x 10(4) s(-1) > circular 2.9 x 10(3) s(-1)) showed greater protein extractability, higher index of surface hydrophobicity, and enhanced water solubility index indicating significant breakdown of protein aggregates. Higher viscoelastic moduli (G' and G '') and apparent viscosity were observed for slit die extrudate dispersions. However, low flow behavior indices (0.04-0.23(-)) and a high viscous activation energy (43 kJ/mol) of slit die extrudate dispersions implied their shear and temperature sensitivity, respectively. Thus, extrudate functionality can be optimized by selection of the appropriate die design.

关键词： Lactic acid bacteria   Probiotics   Ready to eat   Functional foods   Shelf life  

摘要： The consumption of probiotic foods has increased in recent years due to consumer concerns related to healthy diets. In this study, strawberries were used as an alternative product to deliver probiotics and the study aimed to investigate the effect of Lactobacillus rhamnosus on microbial and physicochemical quality of strawberries during refrigerated storage. For this purpose, probiotic Lactobacillus rhamnosus and inulin were added to gelatin-based coatings and applied to fresh strawberries. Probiotic survivability, microbial and physicochemical quality parameters of strawberries were monitored during 16 d of refrigerated storage. According to the results, gelatin-probiotic coatings and gelatin-probiotic-inulin coatings increased the shelf-life of strawberries compared to the control. These coatings significantly decreased the weight loss in strawberries and did not change the quality parameters (pH, titratable acidity, and total soluble solids) during storage. Gelatin-probiotic coatings slowed down fungal growth and total aerobic mesophilic counts in strawberries. While the initial count of Lb. rhamnosus was 11 log CFU g(-1), it was found as 8.9 log CFU g(-1) and 7 log CFU g(-1) on the 10th and last day of the storage, respectively. These results revealed that probiotic incorporated gelatin films can be an alternative way to deliver probiotics and improve the shelf-life of perishable fruits.

关键词： aluminate solutions   hydroxo forms   phase diagrams  

摘要： This bibliographical review represents the published data on the composition and structure of aluminate ions in solutions with varied Al(III) and NaOH concentrations. The results of investigations of the partial and integral properties of aluminate solutions regarded as a ternary NaOH-NaAl(OH)(4)-H2O system are given. The phase diagrams of the ternary Na2O-Al2O3-H2O system for temperatures of 30, 95, 110, 130, 150, and 180 degrees C are presented, and the compositions of the solid phases existing in equilibrium with the corresponding saturated aluminate solutions are specified.

关键词： Chitosan   Edible films   Crab-uca  

摘要： The fish industry generates waste that negatively impacts the environment. Providing solutions that minimise this impact has become an interesting challenge in the last decades. Crab residues contain chitin in their chemical composition, which upon deacetylation affords chitosan, a polymer with potential applications in films and/or edible coatings. The present work aimed at the production and characterisation of chitosan films from crab-uca (Ucides cordatus) residues. The employed methodology led to the production of chitosan with a deacetylation degree of 92%. Several films were formulated using three concentrations of chitosan (1.5%, 2.0%, and 2.5%) and glycerol (0.30%, 0.45%, and 0.60%). In general, the edible films composed of chitosan from crab-uca and glycerol presented good optical and mechanical properties, as well as satisfactory WVP (Water Vapor Permeability) and solubility values. Chitosan filmogenic solutions at different concentrations showed antimicrobial activity against all the standard bacterial strains studied. The film with 1.5% chitosan and 0.6% glycerol has better properties for food application. The produced films have great potential for the development of future biodegradable packaging materials.