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关键词： Soy protein isolate and hydrolysate   physicochemical properties   probiotic encapsulation   gastrointestinal environment   stability  

摘要： The objective of this study was to prepare protein isolate from defatted soybean and identify an optimal hydrolysis protocol to create improved hydrolysates and ascertain the optimum encapsulation technique for probiotics. Soy protein isolate (SPI) was prepared using an alkaline extraction procedure for solubility within a neutral, beverage-specific pH range. The soy protein hydrolysate (SPH) was prepared from aqueous extracted SPI using pepsin. The physicochemical properties of the SPH were investigated by solubility, degree of hydrolysis (DH), surface hydrophobicity, and electrophoresis. Hydrolysates from 2, 2.5, and 3 hr of hydrolysis time achieved the suitable DH between 2.5% to 5.0%. The 2.5 to 3 hr hydrolysates were also significantly more soluble than SPI at all pH levels from 85% to 95% solubility. Surface hydrophobicity of the hydrolysates ranged from 15 to 20S(0)values. Alginate (1%), resistant starch (2%), and probiotic culture (0.1%) were used as an encapsulation agent to protect probiotics. Alginate microcapsules were observed to be 1 mm in size using environmental scanning electron microscopy. The dried SPH and encapsulated probiotics with alginate in a dry powder formulation were tested for its gastrointestinal resistance and probiotic viability underin vitrosimulated digestion. Approximately 1-log decrease was observed for all experimental groups after simulated digestion (final log colony forming units [CFU]/mL range: 6.55 to 6.19) with free probiotics having the lowest log CFU/mL (6.10 +/- 0.10) value. No significant difference was observed among experimental groups for probiotic viability (P= 0.445). The findings of this research will provide an understanding of formulation for easily digestible protein and encapsulated probiotics. Practical Application The findings of this research provide an understanding of improved formulation for more suitable soy protein hydrolysate and viability of encapsulated probiotics in gastrointestinal environment. Pr

关键词： Halloysite   Thermal activation   Meta-halloysite   Kinetic reaction   Rheology   Geopolymer   Mechanical properties  

摘要： In this paper, four samples of meta-halloysite from widely available Cameroon halloysite clay calcined at 600, 650, 700 and 750 degrees C, respectively, and the resultant geopolymer binders were systematically characterized. Isothermal conduction calorimetry (ICC) was used to measure the reaction kinetics of meta-halloysite geopolymers at room temperature during 48 h. The increase in reaction rate and in heat released correlates with the thermal activation temperature. It was typically found that the increase of thermal activation temperature (from 600 to 750 degrees C) enhances the amorphous or reactive phase content from MH600 to MH750 samples. This results in an improvement of rheological behaviour and setting time of the fresh meta-halloysite based geopolymer pastes. The hardened meta-halloysite based geopolymers were amorphous, compact and dense according to Xray diffractometry (XRD) and Scanning Electron Microscopy (SEM). The compressive strength of resultant products increased with the activation temperature, up to 750 degrees C (74 MPa at 180 days). Therefore, the best temperature in view of the highest strength of meta-halloysite geopolymer cured at room temperature is 750 degrees C, although the lower increase in mechanical performance (7.3%) gained between GPMH700 and GPMH750 is limited. Thus, thermally activated halloysite clay appears to be a promising candidate for geopolymer synthesis.

关键词： bilayer emulsion   myofibrillar proteins   starch   beta-1,3/1,6-D-glucan   rheological properties   sensory analysis  

摘要： BACKGROUND: In recent years, consumer interest in low-fat foodstuffs having a clean label and potential benefits over physiological functions has shown a growing trend. beta-1,3/1,6-d-Glucans (BGs) fromSaccharomyces cerevisiaehave been recognized as excellent immune-modulating compounds. Bilayer-stabilized oil-in-water emulsion gels (BEGs) containing oil droplets covered by myofibrillar proteins-gum arabic membranes were used for entrapping BGs in the inner phase. This study investigated the effects of starch type (waxy maize starch, WMS;potato starch, PS) and concentration (0.0-50 g kg(-1)) on the physicochemical properties of BEGs composed of: 200 g kg(-1)rapeseed oil, 40 g kg(-1)myofibrillar proteins, 14 g kg(-1)gum arabic, 15 g kg(-1)BGs, 1 g kg(-1)citric acid. RESULTS: The results showed that BGs were successfully incorporated into the inner phase of BEGs and stability testing showed no separated oil and sediment layer. BEGs were characterized by droplet diameter of d(3,2)= 3.62 +/- 0.209 mu m and electrical charge of the outer membrane of -27.4 +/- 0.257 mV. Increasing starch concentration significantly (P < 0.05) affected values of the studied rheological parameters, but to a greater extent in relation to PS than WMS. Sensory analysis showed that BEGs were most desirable at WMS and PS concentrations of 40-50 and 30-40 g kg(-1), respectively. CONCLUSIONS: BEGs containing oil droplets covered by myofibrillar proteins-gum arabic membranes can be used as carriers for insoluble beta-glucans and manufactured with a wide range of rheological properties and sensory features desired by consumers. (c) 2020 Society of Chemical Industry

关键词： superparamagnetic iron oxide nanoparticles   FTIR   DLS   SEM   XPS   oxygen uptake  

摘要： The present study focuses on the effects of the physicochemical properties of superparamagnetic PEG-modified, positively charged, and negatively charged iron oxide nanoparticles (SPIONs) on their reactivity with hydrogen peroxide. Our hypothesis was that the reactivity of SPIONs in this reaction would depend on their surface properties. The comparative study of the nanoparticles with DLS and TEM revealed the average sizes of PEG-modified, positively charged, and negatively charged SPIONs. We observed that the reactivity of negatively charged SPIONs with hydrogen peroxide was less than that of positively charged SPIONs and that of these second nanoparticles was less than that of PEG-modified SPIONs. This difference in the reactivity of these SPIONs with hydrogen peroxide was attributed to the presence of carboxyl or amine groups on their surface. However, the values of the rate constants of the reactions of PEG-modified, positively charged, and negatively charged SPIONs with hydrogen peroxide showed that the reaction of negatively charged SPIONs with hydrogen peroxide was more rapid than that of PEG-modified SPIONs and the reaction of these second SPIONs with hydrogen peroxide was more rapid than that of positively charged SPIONs. The surface study of the SPIONs using XPS showed that the high-resolution spectra of these nanoparticles changed after reaction with hydrogen peroxide, which indicates their surface modifications. These investigations can help develop more appropriate nanoparticles with controlled physicochemical properties.

关键词： thermal treatment   synthesis   kinetics   photocatalytic activity  

摘要： Precursor CaCu3Ti4O12 has been obtained using solution method in acetic acid medium, it was annealed at 100, 200, 400, 600 800, and 1100 degrees C. Sintered powders have been studied by physicochemical methods of analysis. According to X-ray powder diffraction, completely formed crystal structure CaCu3Ti4O12 exists at 1100 degrees C, the particle size of the prepared powder is 1-10 mu m. Thermal analysis with allowance for mass spectrometric analysis system of vapor phase has revealed process mechanisms. Effect of dried at 100 degrees C powder of precursor and CaCu3Ti4O12 on the photocatalytic activity of Rhodamine B decoloration has been shown. Pseudo-first and pseudo-second order kinetics for Rhodamine B adsorption on samples annealed at 100 and 1100 degrees C has been revealed.

关键词： Akebia trifoliata (Thunb.) Koidz. seeds   Dietary fiber   Ultrasonication assisted enzymatic hydrolysis   Physiochemical properties   Hypoglycemic   Hypolipidemic  

摘要： Dietary fiber extracts from Akebia trifoliata (Thunb.) Koidz. seeds were generated using alkaline extraction, enzymatic hydrolysis as well as physical pretreatments including ultrasonication, shear emulsifying and microwave. Compared with the basic alkaline hydrolysis, cellulase-assisted extraction exhibited the highest water holding capacity (7.99 g/g), cation exchange capacity (0.55 mmol/g), glucose adsorption capacity (1352.33 mu mol/g) and pancreatic lipase inhibition (37.69%). Ultrasonication pretreatment before both the preceding procedures increased the oil holding capacity (3.95 g/g) and alpha-amylase inhibition (6.81%) of the extracted fiber. Microwave pretreatment generated fiber possessing the greatest specific surface area (137.70 m(2)/kg), water swelling capacity (1.25 mL/g), adsorption capacity (4.14 mg/g, pH = 2) and sodium cholate adsorption capacity (38.68%). However, shear emulsifying gave the lowest crude yields (57.72%), glucose absorption capacity (22.09 mg/g), alpha-amylase inhibition (2.77%) and pancreatic lipase inhibition (22.61%) though it contained highest levels of soluble fiber (6.40 g/100 g) and lowest crystallinity (33.6%). A fuzzy statistical evaluation indicated that ultrasonication assisted enzymatic hydrolysis was the most efficient improvement in the overall properties of the dietary fiber. These results provide valuable information for the potential use of A. trifoliata seeds as a new food ingredient and for extraction of dietary fiber from this plant.

关键词： Microencapsulation   Oxidative Stability   Sacha inchi   Spray drying  

摘要： The aim of this work was to obtain sacha inchi oil (SIO) microcapsules from two different species, Plukenetia volubilis L. (SIVO) and Plukenetia huayllabambana L. (SIHO), using different biopolymers as wall materials and spray drying technology. The physicochemical characteristics such as encapsulation efficiency, particle size, morphology and oxidative stability were analyzed in order to select the best formulation that could potentially be used as an ingredient in the development of functional food. Bulk SIO and four formulations were tested for each oil ecotype, using different encapsulating agents: maltodextrin (MD), Arabic gum (AG), whey protein concentrate (WPC) and modified starch HI-CAP (R)-100 (H). Microcapsules made of H presented the highest oxidative stability and encapsulation efficiency compared to AG, AG:MD or AG:MD:WPC formulations.

关键词： Black pepper   Essential oil   Extraction   Antimicrobial activity   Non-isothermal decomposition kinetic  

摘要： Black pepper oils have been investigated frequently in the recent years. However, there is a significant variation in physicochemical properties and bioactivity of oils depended on extraction techniques. In this study, the systemic investigation of four various extraction methods was performed to evaluate the physicochemical characterizations, antioxidant and antibacterial activity. The investigation of H-1 NMR, FTIR and UV-Vis spectra confirmed presence of non-volatile components in oils extracted through supercritical CO2 and hexane-soaking extractions which induced their typical thermal properties. The isothermal behaviour of extracted oils related to evaporation was within range of 3.2-7.3% (w/w) at 27 degrees C. The SEM images of the black pepper confirmed different operation manners of mechanism between extractions using the solvents and heating process. The lowest MIC for both essential oils from conventional hidrodistillation and microwave-assisted hidrodistillation against two bacteria including E. coli and B. subtilis were found to be 137 mu g mL(-1). The non-isothermal decomposition kinetics were investigated on the essential oil of microwave-assisted hydrodistillation extraction. The activation energies and pre-exponent factors of nonisothermal decomposition were found to be in range of 36.5-73.7 KJ mol(-1) and 4.98 x 10(3)-1.97 x 10(8) s(-1), respectively, dependent on conversional fractions of the oil. The results revealed that chemical components, physicochemical properties and bioactivity of black pepper essential oils depended on the extraction techniques. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.

关键词： Aspergillus awamori CICC 2040   Extraction   Mango juice   Polygalacturonase   Pretreatment  

摘要： This study investigated the effect of combined NaOH and microwave pretreatment of orange peel on the efficacy of polygalactumnase, produced by Aspergillus awamori CICC 2040, in mango juice extraction. Mango juice extracted with polygalacturonase produced using pretreated orange peel (PUE) had a higher yield than CRE (mango juice extracted with polygalactumnase produced using untreated orange peel) and CME (mango juice extracted with commercial polygalactumnase). Significantly (p < 0.05) higher soluble solids, total sugar, total carotenoid and phenolic contents, and percentage transmittance were recorded for PUE compared to CRE. However, CRE had a higher reducing sugar, pH, vitamin C, and pectin. Rheological characterization using Power Law, Herschel-Bulkley, and Casson models showed that PUE had better flow characteristics than CRE. The sensory evaluation result showed that PUE was more preferred than CRE and compared favourably with CME in terms of colour, mouthfeel, and overall acceptability. This study showed that the pretreatment of orange peel enhanced the efficacy of polygalacturonase in mango juice extraction.

关键词： Cephalopod   collagen type II   histology   paramyosin   proteomic identification  

摘要： To perform improvements in food science, it is fundamental to understand the physicochemical properties of proteins since their interaction with other macromolecules plays an essential role in food systems. Collagen and paramyosin help in the maintenance of the matrix structure cells, the textural behaviour and the technical functionality of the protein concentrates;because of this, their identification and characterisation are necessary. Cephalopods species have shown differences in the distribution of its muscle fibres. The amino acid profile of jumbo squid showed a high content of glycine and hydroxyproline, while octopus showed a high content of acidic amino acids. The thermal profile of jumbo squid showed an endothermic transition at 117 degrees C, which octopus did not present. Moreover, the proteomic identification confirms the identity of paramyosin with 33% coverage to paramyosin from Dosidicus gigas and a 4% coverage to collagen type II from Sepia pharaonis on octopus and jumbo squid, respectively.