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关键词： Sigumjang (fermented barley bran)   Marinated meat   Umami taste   Pork loin  

摘要： Sigumjang is a traditional Korean fermented barley bran consumed in the Gyungsang-do area. In this study, pork loin was marinated with sigumjang, and its physicochemical and textural properties were investigated. Sigumjang-marinated pork loin (SMPL) displayed an attractive yellowish-brown overall color. SMPL's pH marginally increased during storage and finally equilibrated to the pH of sigumjang, 5.5, on day 14. The amino-type nitrogen content of SMPL increased linearly during the marination period. Due to the lower extractability and higher pH compared to the control, the volume of myofibrillar fragments in SMPL decreased during the marination period. SMPL showed an increase in free amino acids related to umami (Asp and Glu) and sweet (Ser, Thr, Ala and Gly) tastes compared to the control. These may indicate improvement of sensory qualities of SMPL. The results also provide valuable information for the use of sigumjang in the development of novel meat products.

关键词： Struvite   Human urine   Nutrient recovery   Struvite precipitation   Phosphate   NPK  

摘要： Since human urine alone contributes to 90% of phosphorous (P) and 50-70% of nitrogen (N) load to municipal wastewater, retrieval of nutrients in the form of struvite (magnesium ammonium phosphate) from urine has gained much attention as it can act as an excellent slow-release fertilizer for plant growth. The present study aimed to comprehend the effect of urine storage on its physicochemical characteristics for the recovery of ammonium and phosphate in the form of struvite by adding magnesium chloride as an external source of magnesium (Mg). Various influencing factors such as pH, conductivity, salinity, total dissolved solids, and ion concentrations of phosphate, ammonium, calcium, nitrate, sodium and potassium were monitored over a period of 25 days to delineate its role on struvite recovery. The highest yield of 619.3 +/- 54.41 mg L-1 of struvite was obtained on day 24. It was found that phosphate and ammonium recovery reached up to 90% with the storage of 25 days. Excessive addition of Mg increased both struvite yield and phosphate recovery (by 20%) but affects struvite purity undesirably due to the formation of struvite analogs. Statistical analysis with Spearman's coefficients revealed that total dissolved solids exhibited a strong positive correlation for struvite yield.

关键词： Hull-less barley starch   Microwave   Gelatinization   Viscosity  

摘要： Waxy and non-waxy hull-less barley kernels and their isolated starches were irradiated under different microwave conditions (power 640, 720, and 800 W, time 60, 120 and 180 s). Changes in physicochemical properties were studied to investigate the effects of microwave irradiation (MWI) on in-kernel starches and isolated starches. For in-kernel starch, microwave reduced the ratio of 1047/1022 cm(-1) wavelengths, gelatinization enthalpy (Delta H-g) and relative crystallinity (RC), indicating that microwave of starch within the cells disrupted the crystalline regions. For isolated starch, microwave decreased the ratio of 1047/1022 cm(-1) wavelengths but increased Delta H-g of isolated starch, indicating that microwaving resulted in disruption of amorphous structure and an increase in the amount of remaining double helix structure. Moreover, viscosities of in-kernel starches decreased as microwave power and time increased, but this was not observed in isolated starches. Microwave treatment induced an enhancement of gelatinization temperature for non-waxy starches (NWS) but decreased in waxy starches (WS). Microwave had a greater effect for swelling power and solubility on in-kernel MWI-WS than MWI-WS, whereas the reverse results were found between in-kernel MWI-NWS and MWI-NWS. The results indicated that amylose plays a profound role in the properties of isolated and in-kernel starches during microwaving.

关键词： Protein adsorption   Nanomaterials   Toxicity   Indium-tin oxide   Physicochemical properties  

摘要： The Organisation for Economic Co-operation and Development has listed thirteen engineered nanomaterials (ENM) in order to investigate their toxicity on human health. Silicon dioxide (SiO2) and titanium dioxide (TiO2) are included on that list and we added indium fin oxide (ITO) nanoparticles (NPs) to our study, which is not listed on OECD suggested ENM to be investigated, however ITO NPs has a high potential of industrial production. We evaluate the physicochemical properties of SiO2 NPs (10 - 20 nm), TiO2 nanofibers (NFs;3 length) and ITO NPs ( < 50 nm) and the impact of protein-corona formation on cell internalization. Then, we evaluated the toxicity of uncoated ENM on human lung epithelial cells exposed to 10 and 50 mu g/cm(2) for 24 h. TiO2 NFs showed the highest capability to adsorb proteins onto the particle surface followed by SiO2 NPs and ITO NPs after acellular incubation with fetal bovine serum. The protein adsorption had no impact on Alizarin Red S conjugation, intrinsic properties for reactive oxygen (ROS) formation or cell uptake for all types of ENM. Moreover, TiO2 NFs induced highest cell alterations in human lung epithelial cells exposed to 10 and 50 mu g/cm(2) while ITO NPs induced moderated cytotoxicity and SiO2 NPs caused even lower cytotoxicity under the same conditions. DNA, proteins and lipids were mainly affected by TiO2 NFs followed by SiO2 NPs with toxic effects in protein and lipids while limited variations were detected after exposure to ITO NPs on spectra analyzed by Fourier Transform Infrared Spectroscopy.

关键词： Surface nanotopography   Self-assembly   Mesoporous zirconia coating   Calcium doped-zirconia   Cell growth  

摘要： In this work, the effects of surface chemistry and nano-topography of un-doped and Ca-doped zirconia coatings were investigated. The study aimed at providing new insight on how to improve the interfacial properties and biocompatibility of metallic and ceramic biomedical implants for hard tissue applications through the surface modification treatments. To this end, pure and Ca-doped zirconia mesoporous coatings were prepared by wet synthesis and structure self-assembly. The physicochemical properties of mesoporous surfaces were investigated by TEM and XRD. In addition, contact angle and XPS unveiled the wettability and surface chemistry of zirconia surfaces. Our findings highlight the role of Ca in increasing stability of the mesoporous structure at high calcination temperature, applied to remove the templating agent. In vitro assays focused on the proliferation of Saos-2 human osteoblastic cells on the meso-structured zirconia coatings, which resulted to be enhanced on Ca-doped surfaces.

关键词： Hardness  

摘要： Puffed rice is an expanded breakfast cereal obtained by high temperature short time heat treatment of salt-treated parboiled rice. This intense heat results in deformation and phase transition within the grain and delivers an expanded porous structure. Such transformations essentially govern the final puffed rice quality and its physicochemical attributes. They commence during pretreatment and proceeds till puffing. These properties of rice such as expansion, hardness, degree of gelatinization, glass transition temperature, crystallinity, color, nutrient content, porosity, and microstructure are altered during the processing of puffed rice from pretreated parboiled rice. This review attempts to address such materialistic changes in the rice matrix during puffed rice production that would help a researcher to understand the associated changes in physicochemical and nutritional characteristics. Practical applications Studying the changes in the material properties associated with processing conditions is a useful approach to understand final quality of puffed rice. The review is a detailed study of parameters like expansion, hardness, degree of gelatinization, glass transition temperature, crystallinity, color, nutrient content, porosity, and microstructure that influence the final product characteristics of puffed rice and help a manufacturer to produce an acceptable product by exercising strict control on them. Insight on changes brought about by alteration in these characteristics are thus of paramount importance. This is because it can help individuals to produce puffed rice of optimized quality, correct product defects, and cause alterations in the end-product. Researchers working on possible future applications can have a thorough background knowhow. Thus, the work would bear extreme commercial and scientific importance.

关键词： Crystallinity of starch   Digestibility of starch   Heat moisture treatment   Modified potato starch  

摘要： Potato starch was subjected to heat moisture treatment (HMT) in which the temperature and moisture content were varied. Two different levels of moisture content (30 and 35%) and temperature (100 and 120 degrees C) were selected. The crystallinity of the starches decreased after HMT, as confirmed by both X-ray diffraction (XRD) and Fourier Transform Infra-Red (FT-IR) analysis, and the XRD pattern of native starch changed from B-type to A+B type after HMT. Swelling, solubility, clarity and freeze-thaw stability of the HMT starches were less than native starch and were found to be dependent on both temperature and moisture content. Pasting viscosities of the modified starches were significantly lower than native starch and were found to be more for the starches treated at 120 degrees C than the starches at 100 degrees C. The pasting temperature increased after modification. The firmness of the modified starch pastes increased whereas the consistency decreased. The formation of resistant starch increased after HMT.

关键词： Authentication   Fat   Fatty acid   Greek PDO cheese   Moisture   NaCl   pH  

摘要： Greek protected designation of origin (PDO) cheeses are well-known for their quality and nutritive value. One hundred and twelve samples from 21 Greek PDO cheeses, a non-PDO and a potential PDO were analyzed for fatty acid (FA) profile and several physicochemical parameters including moisture, fat on dry matter (FDM), protein content, pH and salt content. Analyzed hard and semi-hard cheeses were Sfela, Kefalograviera, Kasseri, Ladotyri Mytilinis, Formaella Arachovas Parnassou, Graviera Agrafon, Graviera Kritis, Metsovone, Graviera Naxou, Mastelo, Batzos and San Michali. Soft, spread and whey cheeses included Kopanisti, Xynomyzithra Kritis, White cheese, Kalathaki Limnou, Manouri, Feta, Xygalo Siteias, Galotyri, Katiki Domokou, Pichtogalo Chanion and Anevato. The profile of 37 FAs combined with physiochemical properties was utilized to discriminate cheeses by label (cheese identity), cheese type (hard, semi-hard, soft, spread and whey) and milk type (cow, goat, sheep and combinations). The study found that Sfela had the highest salinity, Manouri the highest FDM and San Michali the highest content of proteins. Regarding FAs, the dominant ones in almost all cheeses were C-14:0, C-16:0, C(18:0)andcis-9C(18:1). For classification concerning cheese identity, the most significant parameters were moisture, fat, C18:2n-6c, pH and salt. The most significant discriminants by cheese type were pH, moisture, FDM, salt and C(16:0)while C-10:0, C-11:0, C-14:1, C18:2n-6c, C-20:0, C(20:3n-6)and saturated FAs were more influential to separate by milk type. Results depict the FA profile of Greek PDO cheeses and show that in combination with physicochemical characteristics can be used as authenticity markers.

关键词： Reversed-phase liquid chromatography   Quantitative structure-retention   relationships   Solvation parameter model   Acid dissociation constant   Formation constant   Soil-water sorption constant   Surrogate chromatographic models  

摘要： The physicochemical properties of small molecules that can be determined by retention measurements in reversed-phase liquid chromatography include solvent-based properties inferred from equilibrium processes occurring predominantly in the mobile phase and sorption properties for materials which can be used as stationary phases inferred from solute-stationary phase interactions. In addition, physicochemical properties can be estimated from correlation models based on surrogate chromatographic systems with a similar capability for intermolecular interactions to the chemical or biological system. Examples of properties determined by direct methods include molecular descriptors (solvation parameter model), acid dissociation constants, formation constants, and surface properties of solids determined by inverse liquid chromatography. Examples of properties estimated by indirect methods include hydrophobicity, lipophilicity, n-octanol-water partition constant, soil-water sorption constant, non-specific toxicity to fish and microorganisms, and permeation coefficients for the blood-brain and skin-water barriers. Since all approaches depend on an accurate measurement of chromatographic retention parameters typical operational and mechanistic problems are discussed from the perspective of data quality. Fundamentally the accuracy of direct methods is limited by stationary phase heterogeneity and indirect methods by the limited number of suitable surrogate chromatographic models. (c) 2020 Elsevier B.V. All rights reserved.

关键词： microencapsulation   spray drying   ascorbic acid loading content  

摘要： BACKGROUND There is increased interest in the food, pharmaceutical and cosmetic industries in using ascorbic acid as an important component in the human diet for health support and disease prevention. However, its use as an ingredient is limited by its high instability and sensitivity to environmental conditions. Microencapsulation technology has been proposed to increase the stability of ascorbic acid. The aim this work was to evaluate the effect of ascorbic acid loading rate on the physicochemical properties of encapsulated ascorbic acid. Loading contents of ascorbic acid of 6%, 9%, 18%, 36%, 54% and 72% were trialled using spray drying in conjunction with starch-based encapsulating agents. RESULTS The results showed that the loading content has a significant effect on ascorbic acid retention, yield, moisture content, water activity, colour change, particle size and distribution of microcapsules. Morphology of microcapsules also was assessed using environmental scanning electron microscopy, showing that the microcapsules had good structure and integrity for a loading content of 18% and even as high as 54%. At levels beyond this, capsules showed a lack of coherence and integrity of the outer shell. CONCLUSIONS The results indicated that ascorbic acid microparticles at various loading rates have a substantial impact on physical and chemical properties of microcapsules. Loading content can be selected to ensure colour uniformity and minimal effects on colour during food fortification processes. (c) 2020 Society of Chemical Industry