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The potential of utilizing black soldier fly larvae (BSFL) protein in food applications requires comprehensive understanding of their techno-functionalities under various processing conditions. This study aimed to investigate the gelling behaviour of BSFL proteins through characterising their aggregation and rheological properties at different temperatures (55–95 °C). The results of turbidity, particle size distribution, polydispersity and molecular weight distribution showed that BSFL protein aggregation was enhanced at higher temperatures. The reduction of zeta potentials and total sulfhydryl groups implied that heat induced conformational changes had taken place through electrostatic interactions and disulfide bonds formation. The changes in secondary structures composition demonstrated that the formation of β-sheet structures plays important role in BSFL protein aggregation. The gelation kinetics and mechanism of BSFL protein might be explained from their thermo-rheological behaviour, which includes partial unfolding, rapid aggregates formation, initial gel formation, gel network sustainment and gel reinforcement steps at different stages of the heating cycle. The variation in viscoelastic properties suggested that heating at higher temperatures aided the formation of BSFL gels with higher strength and elasticity. The power law parameters showed that the stability of heat-induced BSFL gels were greatly enhanced after heating at higher temperatures. Overall, the temperature dependence of BSFL protein aggregation and gelling properties are clearly demonstrated in present study. These results are useful for the selection of appropriate heating conditions to attain specific BSFL protein gel texture. [ABSTRACT FROM AUTHOR]

Shrimp is one of the most preferred seafood for consumption. The high water content and nutrients place shrimp in the category of perishable fast spoiling foods. In order to avoid deterioration of their quality, it is necessary to freeze and store them at low temperatures. Fluctuations in temperature can cause thawing and refreezing with recrystallization. In frozen products, the amount and size of ice crystals play a major role in the quality of these products. Despite the wide application of freezing, various histological, physicochemical, microbiological, enzymes and pH changes occur with varying degrees of manifestation. The objective of the review was to discuss the effect of freezing on the quality of shrimp used for human consumption. [ABSTRACT FROM AUTHOR]

Physicochemical and sensory changes of fish were investigated during marination of rainbow trout. Equilibration in the acidity of A (2% acid, 8% salt), B (4%, 8%), C (2%, 12%), and D (4%, 12%) groups took place at the 24, 24, 30, and 30th hours, respectively; in salt, it occurred at 36, 42, 42, and 36th hours, respectively. With ripening, a* value decreased, and b* value and hardness increased. Salt concentration affected acid taste; acid affected salt taste. This study revealed the effects of the ratio of acid and salt used in rainbow trout marinade on ripening and the resulting changes in sensory properties. [ABSTRACT FROM AUTHOR]

Polymer electrolyte membrane fuel cells (PEMFCs) are the core technology of the steadily growing hydrogen (H2) economy as they can convert chemical energy, in the form of H2, to electrical energy. If the H2 is derived from (green) hydrocarbons, via steam reforming and the water‐gas‐shift reaction, then it would contain small amounts of carbon monoxide (CO, 0.5–2 %), among other gases. CO poisons the platinum‐based anode catalyst in the PEMFC, and the current recommendation is to decrease its concentration to below 0.01 % (or 100 ppm) in the H2‐rich PEMFC feed. The preferential oxidation of CO (CO‐PrOx) is a promising strategy for decreasing the CO concentration, and base metal oxide catalysts have shown great potential in this regard. However, such catalysts tend to undergo physicochemical changes that cause undesirable catalytic activity and selectivity changes. This review discusses the different base metal oxide catalysts that have been evaluated in CO‐PrOx, while paying special attention to the various in situ and operando techniques that have been used to monitor the physicochemical changes of base metal oxides during operation. We conclude the review by highlighting the recent and possible future attempts of circumventing the undesired physicochemical changes of base metal oxides during CO‐PrOx. [ABSTRACT FROM AUTHOR]

Testudinoidea represents an evolutionarily unique taxon comprising both turtles and tortoises. Turtles and tortoises are closely associated groups that inhabit contrasting habitats associated with unique physio-ecological challenges, which enable distinct adaptive evolutionary strategies. To compare the pattern and strength of Darwinian selection and physicochemical evolution in both turtle and tortoise mitogenomes, we used divergence and selection analyses. We analysed codon models and changes in structural and biochemical properties in mitochondrial protein coding genes (PCGs) of oxidative phosphorylation (OXPHOS) respiratory system. We detected strong evidence of positive selection in turtles whereas weak selection pressure were observed in tortoises. In turtles, highest gene and site-wise positive selection was detected in Platysternidae family. Among turtles, NAD2, NAD4 genes of OXPHOS Complex I, and COB gene of Complex III showed more positively selected sites, indicating convergent evolution. Across Testudinoidea, we observed pervasive selection in NAD3 and lineages specific selection in NAD2. This study revealed specific mitogenome sites responsible for physiochemical changes influencing positive selection in turtles and tortoises. Hence, our study provides insight into the selection pressure shaping distinct evolutionary pathways in two closely related reptiles which are often overlooked. [ABSTRACT FROM AUTHOR]

Background: Quinoa was suggested to substitute in noodles with positive effects of cardiovascular disease, metabolic, and gastrointestinal systems. However, quinoa fresh noodles (QFN) were hard to preserve but constrain industrial production. The deteriorative changes in the quality and relative parameters of QFN at 25 ± 1°C are lacking and needed to investigate. Findings: In this study, QFN was sampled every 12 h at 25 ± 1°C, and found that the total plate count exceeded safety limit (5 log10 CFU/g) in 24 h. Bacillus, Staphylococcus, Aspergillus, and Filobasidium were the dominant spoilage microorganisms, where Bacillus was significantly increased and accounted over 90% of bacteria after spoilage. The volatile compounds changed significantly, where aldehydes decreased from 58.25% to 30.09%, while easters and alcohols increased from 2.29% to 14.84%, and 7.78% to 20.28% separately. With increasing of storage time, the water content and water activity decreased. Besides, strongly bound water decreased from 12.51% to 7.63%, weakly bound water and free water increased. The color of QFN turned to dark and red, where a value increased from 2.11 to 3.82, while L value decreased from 75.20 to 64.56. pH of QFN also decreased during storage. The quality index of QFN was qualified with decreased texture properties (hardness, springiness, and chewiness) and significantly increased cooking loss rate (8.65%–12.74%) and cooked broken rate (0%–26.67%). Conclusions: The storage time of QFN was 24 h at 25 ± 1°C. The textural changes and certain indexes changed significantly after spoilage. And relative indexes of QFN qualities presented significant correlation with microorganisms. Significance and Novelty: Bacillus in QFN may contribute significant changes in spoilage. The correlation analysis figured out the possible reasons for qualities changes of QFN. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) has become one of the most commonly used polymers in medical devices given its biocompatible, biodegradable and bioabsorbable properties. In addition, due to PLA's thermoplastic behaviour, these medical devices are now obtained using 3D printing technologies. Once obtained, the 3D-printed PLA devices undergo different sterilisation procedures, which are essential to prevent infections. This work was an in-depth study of the physicochemical changes caused by novel and conventional sterilisation techniques on 3D-printed PLA and their impact on the biological response in terms of toxicity. The 3D-printed PLA physicochemical (XPS, FTIR, DSC, XRD) and mechanical properties as well as the hydrophilic degree were evaluated after sterilisation using saturated steam (SS), low temperature steam with formaldehyde (LTSF), gamma irradiation (GR), hydrogen peroxide gas plasma (HPGP) and CO2 under critical conditions (SCCO). The biological response was tested in vitro (fibroblasts NCTC-929) and in vivo (embryos and larvae wild-type zebrafish Danio rerio). The results indicated that after GR sterilisation, PLA preserved the O:C ratio and the semi-crystalline structure. Significant changes in the polymer surface were found after HPGP, LTSF and SS sterilisations, with a decrease in the O:C ratio. Moreover, the FTIR, DSC and XRD analysis revealed PLA crystallisation after SS sterilisation, with a 52.9% increase in the crystallinity index. This structural change was also reflected in the mechanical properties and wettability. An increase in crystallinity was also observed after SCCO and LTSF sterilisations, although to a lesser extent. Despite these changes, the biological evaluation revealed that none of the techniques were shown to promote the release of toxic compounds or PLA modifications with toxicity effects. GR sterilisation was concluded as the least reactive technique with good perspectives in the biological response, not only at the level of toxicity but at all levels, since the 3D-printed PLA remained almost unaltered. [ABSTRACT FROM AUTHOR]

Aims: To investigate characterization of the bacterial community composition and functionality and their impact on substrate biodegradation as well as mushroom yield. Methods and Results: Bacterial diversity, composition and functionality were accessed by DNA‐derived analysis for a sugarcane straw‐based substrate composted for either 5, 10 or 15 days. In addition, carbon and nitrogen losses, carbohydrate conversion and mushroom yields were measured for the different treatments. Changes were observed in the bacterial community diversity and composition after the process started, but not during the composting process itself. Following phase I, Acinetobacter sequences were recovered in high numbers, and selected genes associated with nitrogen metabolism and lignocellulose deconstruction were mapped. Substrate physicochemical composition showed elevated carbon and nitrogen losses after 10 and 15 days of phase I with reductions in mushroom yield. Conclusions: Acinetobacter species appear to play an important role in substrate degradation processes, and a 5‐day phase I period showed a significant higher mushroom yield compared to composting for either 10 or 15 days. Significance and Impact of the Study: This study confers a better understanding of the bacterial community manipulation during the substrate preparation and their influence in substrate selectivity for the Pleurotus ostreatus cultivation. [ABSTRACT FROM AUTHOR]

To comprehend the decline in post-production of pre-cooked flour products, this study examined the impact of curdlan on structural properties and aggregation behavior of pre-cooked wheat gluten (PCWG) during freeze-thaw (FT) cycling. The results revealed that as the number of FT cycles increased, the gel fracture strength and distance of PCWG decreased, while the extractable protein increased. The extent of PCWG deterioration increased with more FT cycles. However, the addition of curdlan mitigated these changes, with a notable effect seen at 0.5% (w/w) addition. Microstructural analysis indicated curdlan's role in enhancing PCWG homogeneity. Secondary structure analysis demonstrated a transition in PCWG's secondary structure from β-sheets to random coils and β-turns as the FT cycle increased. Notably, 0.5% curdlan significantly inhibited this transition. The chemical interaction results suggested that curdlan's impact on changing PCWG's structure was linked to shifts in free sulfhydryl groups, disulfide bonds, and hydrophobic interactions. As the FT cycle increased, the free sulfhydryl content in PCWG rose, while the disulfide bond content decreased. Hydrogen bonding decreased, and hydrophobic interactions increased. These trends were effectively countered by low doses of curdlan (especially 0.5%). However, excess curdlan (0.9%) exacerbated the disruption of PCWG's protein network structure during FT cycling, potentially through steric hindrance effects or hydrogen bonding. In conclusion, this study provides theoretical support for enhancing the quality of PCWG and employing curdlan in frozen flour products. [Display omitted] • The degradation of WG gel properties increased with successive freeze-thaw cycles. • Hydrophobic interactions were strengthened through freeze-thaw cycles. • Phase transitions in the thaw phase rearranged the WG structure. • Excess curdlan could affect gluten aggregation behavior through hydrogen bonding. [ABSTRACT FROM AUTHOR]

Oral textural perception is a complex process that involves tooth fragmentation and salivary lubrication. To reveal the associated in-mouth mechanisms, three stages of testing were conducted in this study, including the initial cooked rice stage (0%), the deformation stage (50%), and the swallowing stage (100%). The total chewing time of high/low heating rate rice (HHRR/LHRR) was 25.46 ± 6.22 s and 22.11 ± 5.02 s, respectively. However, no significant difference in the chewing frequency. The salivary flow rate in LHRR (28.18 mg/s) was higher than in HHRR (22.57 mg/s). At the 0% stage, LHRR had a higher moisture content and expansion rate. At the 50% stage, rice boluses exhibited a significant difference in texture properties measured by instrumental analysis. At the 100% stage, two rice boluses reached similar hardness and chewiness, with smaller particles for swallowing. These results indicated that the deformation stage (50%) played a critical role in differentiating the textural perception. The initial properties of cooked rice influenced chewing manner and salivary secretion, contributing to differences in the reduction of particle size, water migration, and the inner microstructure evolution of corresponding rice boluses. These differences will feed back as different texture perceptions during oral processing. [ABSTRACT FROM AUTHOR]

Changes in the physicochemical properties of wheat gluten (WG) during cooking are mainly dependent on its intramolecular and intermolecular interactions when subjected to high-temperature treatment. In this study, the effects and mechanisms of cooking on the aggregation behavior of WG were investigated. Results showed that an increase in cooking time led to an initial increase and subsequent decrease in WG viscoelasticity, with optimal viscoelastic properties observed at 5 min. As cooking proceeded, covalent cross-linking of WG deepened and the contribution of hydrogen bonds to maintaining WG structure weakened, while the contribution of hydrophobic interactions strengthened. Cooking increased the proportion of gauche-gauche-gauche in the disulfide (SS) bridge conformation and decreased the homogeneity of the WG network. The unfolding of gluten molecules caused by hydrogen bonds breaking and intermolecular cross-linking through hydrophobic interactions and SS formation jointly contributing to the rheological properties of WG. Notably, glutenin (Glu) exhibited more similar physicochemical changes to WG during cooking than gliadin (Gli). Glu was more sensitive to cooking than Gli and formed dense, continuous aggregates prior to Gli. Cross-links formed by Glu occupied the majority of three-dimensional network of WG, while Gli was involved only in the form of branched chains. This may explain why Glu dominates the physicochemical changes of WG during cooking. This study contributes to a deeper understanding of the thermal denaturation mechanism of WG and provides new insights into the processing of flour-based foods. [Display omitted] • Cooking had a dual effect on the viscoelasticity of wheat gluten. • Gliadin underwent different physicochemical changes than glutenin during cooking. • Glutenin was more sensitive to cooking than gliadin. • Gliadin limited the physicochemical changes of glutenin during cooking. [ABSTRACT FROM AUTHOR]

Graphene-based materials are subject to photochemical process when releasing into the environment. In this study, three kinds of graphene-based materials, graphene oxide (GO), soot and graphene (G), were selected to investigate their photoinduced changes of properties and the corresponding reasons. GO underwent reduction-dominant disproportionation, resulting in less oxygen-containing function groups (OFGs) and higher percentage of carbon-centered persistent free radicals (PFRs). Different kinds of soot particles all experienced self-oxidation, expressed as more OFGs, defects and carbon-centered PFRs adjacent to oxygen atom. Oxidative potential (OP) tested by DTT activity showed a decrease in GO but an increase in soot, agreeing with their changes of physicochemical properties. G remained almost unchanged in terms of both physicochemical properties and OP. Photoactivity measured by the productivity of photogenerated electron-hole pair and reactive oxygen species was responsible for above changes and correlated with the inner carbonaceous core. Carbonaceous core can behave as a photocatalyst to initiate photocatalytic reaction, and its oxidation degree (O/C ratio and OFGs content) determines the photoactivity. The relationship among the physicochemical properties, OP, photoactivity and inner microstructure found in this paper will help for better understanding of the environmental behavior and health effects of graphene-based materials. [Display omitted] • Visible light irradiation induces reduction on GO but oxidation on soot. • O/C ratio and OFGs of carbonaceous core are key factors influencing photoactivity. • Photoactivity is responsible for the physicochemical properties and OP changes. [ABSTRACT FROM AUTHOR]

Low-fat meat products always have harder texture, lower juiciness, and worse flavor. Due to their higher water-holding, water absorption, and organic molecule absorption, chia seeds (CHIA) have been applied in powders, nutrition bars, breads, and cookies. Hence, the objectives of this study were to: (1) analyze the nutritional compositions in CHIA; and (2) look for the possible application of CHIA on restructured ham-like products. CHIA has high amounts of α-linolenic acid, crude polysaccharides, and also contains essential amino acids, minerals, and polyphenols. Regarding processing properties of CHIA, a combination of CHIA and carrageenan (CA) increased (p < 0.05) production yield of restructured ham-like products. A scanning electron microscope observation indicated that CHIA and CA addition can assist an emulsification in this ham-like product. Addition of 0.5% CA and 1.0% CHIA in this ham-like product showed the similar overall acceptance as products with added fat. Following storage at 4°C, higher (p < 0.05) purge and centrifugation losses, as well as hardness of this ham-like product can be improved by adding CHIA and CA. CHIA addition also resulted in lower (p < 0.05) lipid and protein oxidation, especially a 1.0% addition. In summary, due to both nutritional addition and improvements on physicochemical and sensorial properties of restructured ham-like products, CHIA seeds have great potential on the development of healthy and good-quality meat products. [ABSTRACT FROM AUTHOR]

This work focuses on the effects of different concentrations of Ca 2+ ions 0, 0.10, 0.15, 0.25, and 0.35% w/w and the steeping time in corn starch-water system with and without heating, as well as the influence of the Ca 2+ concentrations on the pasting profile, regarding the physicochemical changes that take place along the thermal process. The first and second derivatives of the pasting profiles were calculated to identify the main changes originated in the heating and cooling regions. The inclusion of Ca 2+ ions has a strong effect at the end of the pasting profile; below the gelatinization temperature starch grains exhibit a semi-crystalline structure and were still integer, at the peak viscosity, the samples were amorphous as a result of the gelatinization, at the final viscosity the structure was complete amorphous observed in the X-ray patterns. Micrographs of the starch-water system with Ca 2+ show that the morphology changed rapidly and depends on the Ca 2+ concentrations. IR spectroscopy shows that Ca 2+ ions did not form any new chemical bonds, yet only the van der Waals interaction occurred. We demonstrate for the first time the effect of calcium ions on the elastic and plastic regions of the custard and hydrogels. [ABSTRACT FROM AUTHOR]

The wide spectrum of biological properties of sulphur has resulted in its use in pharmaceutical industry, especially in the Indian Traditional Medicines, Ayurveda and Siddha. Native sulphur from rocks, volcanic deposits, hot springs, fossil mineral resources and salt domes has been traditionally used. In the pharmaceutical industry, sulphur is processed to remove elemental and molecular impurities. This purification is performed in Ayurveda through a simple process sodhana mentioned in Rasasastra, which would lead to interesting physicochemical transformations. This paper describes an attempt to evaluate the physical and chemical properties occurring in sulphur due to the sodhana process as well as removal of toxic impurities from native sulphur during this process. The changes to colour, appearance, odour, density, melting point, concentration and structure of sulphur were assessed using physicochemical methods, scanning electron microscopy, inductively coupled plasma mass spectrometry and X-ray powder diffraction. The role of medium for incorporation of organic content was analysed by Fourier transform infrared spectroscopy. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effect of storage temperature and time on nutrients, bioactive compounds, and antioxidant activities of walnut male inflorescences. The results showed that the moisture, saccharides, fat, protein, amino acids, ascorbic acid, phenolic and flavonoid compound contents, and antioxidant activities of walnut male inflorescences were markedly influenced by storage temperature, and different degrees of decrease in these parameters were observed during the entire storage period. Moreover, higher storage temperature had a more significant effect on the nutrients, bioactive compounds, and antioxidant activities of walnut male flowers, and the loss rate of these components at 25°C was higher than that determined at 4°C. However, the results also presented that the ash and mineral contents did not appear to be influenced significantly by the storage temperature, and slightly significant changes were observed in crude fiber throughout storage, which indicated that the influence of storage on the individual mineral and crude fiber content was minimal. Based on the findings in this study, in order to maximize nutrients concentration, walnut male inflorescences should be kept at 4°C for <6 days and be consumed as fresh as possible. [ABSTRACT FROM AUTHOR]

Connective tissue (CT) proteins in jumbo squid ( Dosidicus gigas) play an important role because they are the responsible for the union between various cells; hence, there is a close relationship between their functions and muscle firmness during ice storage. In this study, the thermal resistance and solubility of the CT extracted from the fins, mantle and arms of jumbo squid during ice storage (20 days) was evaluated. The CT was fractionated based on solubility [NaCl-soluble (SSCT) and insoluble (ICT)]. The solubility of the CT was affected during ice storage. An increase in the thermal resistance of the SSCT after 10 days with a subsequent decrease was found in the mantle. Furthermore, the ICT was thermally more resistant than the SSCT in all the anatomical regions. Finally, the electrophoretic profile revealed that structural changes occurred, causing changes in its solubility, due to an increase in the thermal resistance. Practical Applications Jumbo squid ( Dosidicus gigas) is an important seafood resource in Mexico, which is commercialized primarily iced and fresh-frozen. Its muscle connective tissue (CT) has different physicochemical characteristics that differ from other seafood products; it is thermally more resistant and might be responsible for the textural changes during ice storage. Moreover, specific studies about the behavior of CT proteins in such organism may result in improved post-catch management of jumbo squid muscle, focused on the processing of the species in the food industry or anywhere that CT proteins are used as raw material. The main objective of this research is to investigate solubility changes and thermal resistance of CT proteins of iced jumbo squid mantle. [ABSTRACT FROM AUTHOR]

Extensive studies have been conducted on the environmental degradation of multiwall carbon nanotubes (MWCNTs), but primarily focused on the extent and rate of MWCNTs mineralization. Few studies have explored possible structural changes that may occur to MWCNTs during natural or engineered processes. We systematically examined MWCNTs in oxidative coupling reactions in the presence of a common contaminant tetrabromobisphenol A (TBBPA). MWCNTs was modified by the radicals of TBBPA resulting from peroxidase-mediated coupling reaction. Interactions between TBBPA radicals and MWCNTs were definitely confirmed by analyzing the characteristic mass spectrometry response of bromine in TBBPA and the structures of MWCNTs. After reaction with TBBPA radicals for 60 min, the content of bromine contained in MWCNTs was 6.84(±0.12)%, a quantity equivalent to a 501.65(±2.19) mg loading of TBBPA per gram MWCNTs. Modified MWCNTs had better stability and smaller sizes than that of MWCNTs and TBBPA-adsorbed MWCNTs. Assessment using zebrafish embryos revealed that the modified MWCNTs passed through the chorion and entered the embryo inducing acute toxicity, while the MWCNTs/TBBPA-adsorbed MWCNTs was trapped by chorion. These findings indicated that MWCNTs was modified in peroxidase-mediated coupling reactions, and suggested that such modifications may have an influence on the ecological risks of MWCNTs. [ABSTRACT FROM AUTHOR]

We investigated the alterations on bioactive compounds after treatments with ozonated water during the storage of organically and conventionally cultivated mangoes, cv. Palmer. Mangoes were stored in a cold chamber (14 ± 2 °C) for 15 d and evaluated after the harvest and sanitization treatments (chlorine and ozonated water—10 and 20 min) at 7 and 15 d. To simulate the market, after 7 d, mangoes were removed from cold storage and kept at room temperature (27 ± 2 °C) to be analyzed following 4 (7 + 4) and 8 (7 + 8) d at room temperature. The conventionally mango showed higher firmness, regardless of the sanitization system used. Ozonated water did not alter the levels of β-carotene, ascorbic acid, dehydroascorbic acid and phenol in organically or conventionally cultivated mangoes during storage, but when the mangoes, cv. Palmer were transferred to room temperature, the β-carotene level increased. Organically cultivated mangoes showed higher levels of antioxidant activity. Ozonated water can be used as an alternative to chlorine sanitizer without causing damage to mango, cv. Palmer fruit or inducing a decrease in the various compounds and the treatment using ozonated water was efficient for maintaining fruit without microorganisms, preventing the reduction of quality and avoiding the generation of organic waste. [ABSTRACT FROM AUTHOR]

The effects of gamma irradiation on a lignocellulosic biosorbent-coir pith were studied in view of its utilization for separation of metal ions of nuclear importance. The biosorbent was irradiated up to a dosage of 3.6 MGy using a Co source. Physicochemical changes induced by γ irradiation in coir pith, were investigated using fourier transform infrared spectroscopy, thermogravimetric and differential thermal analysis. Irradiation in air had negligible effect on the chemical structure of coir pith. However, irradiation in aqueous medium partially altered the chemical linkages in coir pith; which reflected in marginal decrease in its sorption capacity for strontium. [ABSTRACT FROM AUTHOR]

This study investigates the effects of lime-saturated water and water–CO 2 cyclic recuring on strength recovery of thermally damaged high-performance concretes (HPC). The HPC samples were subjected to elevated temperatures up to 1000 °C in 200 °C increments and underwent recuring. Phase assemblage and distribution, microstructure evolution, and pore structure of the HPC samples were identified. According to the results, recovered compressive strength of the HPC samples with low silica content can surpass their original strength after 600 and 800 °C exposure and recuring. In contrast, HPC with high silica content is unfavorable for strength recovery at temperatures above 800 °C because the low-calcium phases formed have low reactivity. After 1000 °C exposure, only water–CO 2 cyclic recuring coalesces the disintegrated microstructure and recovers the compressive strength. Strength recovery primarily depends on healing the microcracks and large pores rather than the coarsened cement paste. [ABSTRACT FROM AUTHOR]

Oxidation is an important factor for denaturing of whey protein isolate (WPI) during food processing. We studied the effects of chemical oxidation on physicochemical and structural changes along with in vitro digestibility of WPI in this work. Evaluation of physicochemical changes showed that carbonyl level and dityrosine content increased, whereas total and free thiol group levels decreased for oxidized WPI samples. For the structural changes, protein aggregation was measured by surface hydrophobicity, turbidity, and particle diameter, which was increased for oxidized WPI samples. The increase of the secondary structure β-sheets and antiparallel β-sheet also supported the aggregation of oxidized WPI. A direct quantitative relationship between physicochemical and structural changes and protein digestibility indicated that oxidation-related damage restricts the susceptibility of WPI to proteases. In conclusion, WPI had high susceptibility to oxidative stress, and both physicochemical and structural changes caused by severe oxidative stress could decrease the rate of in vitro digestibility of WPI. [ABSTRACT FROM AUTHOR]

Nutraceutical quality of fruits can be influenced by the stage of ripening. The present project objective was to evaluate physicochemical changes of mango cv. Keitt that included total soluble solids (TSS), titratable acidity (TA), firmness and color, concentration of total phenolics (TPC), ascorbic acid (AA), antioxidant capacity (ORAC value), carotenoids, and total dietary fiber (TDF) at 6 postharvest ripening-stages (RS1–6). Results indicated a decrease in firmness from 62 to 0.69 N, while TSS increased from 9 to 17% and TA decreased. Mango TPC increased by 54% at RS2 and at RS3 returned to the original levels. It was found that AA increased by 133% at RS2 and at RS6 showed the lowest value. A correlation between TPC and ORAC value ( R 2 = 0.88) was found. Regarding carotenoids content, there were no significant differences from RS1 to RS4, but at RS6 carotenoids increased 49% in contrast with RS1. Furthermore, TDF increased at RS2 and remained with slightly differences from RS2 to RS5. At RS6, TDF diminished 13% as compared to RS1. Results permitted the visualization of optimum ripening-stages (RS2 and RS6) that contained the highest concentration of specific bio-active compounds in order to produce high-quality products and improve health-benefits. [ABSTRACT FROM AUTHOR]

This study aimed to characterize goji berry (Lycium barbarum L.) fruit across different stages of maturity and ripening in terms of color, firmness, phytochemicals, and metabolic behavior. According to the producer's indication, the goji berry fruit was divided into six classes: early immature (green) to fully ripe (full red). Several maturity indexes were monitored for all classes, including dimension, weight, color (hue angle), firmness, soluble solid content (SSC), pH, and titratable acidity (TA). Fruit dimensions on the plant increased from class 1–6 starting from 8.08 mm in length, 3.95 mm in width, and 0.07 g of weight, to 16.26 mm, 13.15 mm, and 1.29 g, respectively. Soluble solids increased from 2.68% to 23.5%; the highest value observed even after storage. Goji berries showed a rise in respiration rate and ethylene production in the early stages of development. Goji berry stored for 8 d at 25 °C showed significant changes in color, soluble solids, TA, respiration, and ethylene production. Soluble solids from class 5 stabilized around the maximum value of 23% after eight days of storage at room temperature. Their high nutritional value was confirmed by the content of vitamin C, which is comparable to that of citrus fruit. It reached the maximum value of 0.52 g/kg at full ripening, whereas the phenolic content decreased during ripening to values of 2.15 g/kg. The latest contributed considerably to the high antioxidant content of the berries. Results obtained in this study contribute to better understand the postharvest behavior of goji fruits enabling a clearer definition of quality attributes during ripening and, in turn, improving postharvest handling and distribution of goji berries as fresh fruit. • Goji berries are classified into six developmental stages. • Goji berry fruit showed climacteric behavior in the early stages of development. • Vitamin C content increased over ripening, while phenolic content decreased. • We recommend harvesting at stage 5 and not earlier than stage 4. • This information is crucial for postharvest handling and consumption of goji fruit. [ABSTRACT FROM AUTHOR]

The term 'gelatinization' of starch generally describes an irreversible structural change observable on all product design scales ranging from micro to macro level. These structural transformations of starch during thermal impact and in following production steps are highly dependent on several different aspects, which are, however, not sufficiently specified. In order to achieve a better understanding of these heat-induced changes it is necessary to cluster the influencing aspects into the following two categories, raw material properties and process parameters. The development of physical analytical methods with their corresponding gelatinization aspects, in relation to their process parameters, is illustrated in this review. Based on the current knowledge it becomes apparent that no analytical system is present which would allow the investigation of starch gelatinization and the resulting structural changes on different length scales in food products. Therefore, the application of a specified non-invasive online analyzing system to follow the starch gelatinization within a complex food matrix is recommended. [ABSTRACT FROM AUTHOR]

Abstract: Impact of zinc sulphate (ZnSO4) and zinc chloride (ZnCl2) on heat-induced aggregation of natural actomyosin (NAM) extracted from yellow stripe trevally (Selaroides leptolepis) was investigated. In the presence of ZnSO4 or ZnCl2, the transition temperature (T max) of myosin shifted from 47.83±0.30°C to 46.05±0.36 and 46.49±0.49°C, with the coincidental decreases in ΔH from 1.07±0.03J/g to 0.63±0.02 and 0.67±0.04J/g, respectively (P <0.05). Additionally, Ca2+–ATPase activity of NAM decreased with increasing the concentrations of ZnSO4 or ZnCl2 during heating up to 40°C. During heating from 20 to 75°C, higher turbidity, surface hydrophobicity and disulphide bond formation were obtained in NAM added with ZnSO4 or ZnCl2 at temperatures ranging from 40 to 75°C, compared with the control. Nevertheless, a higher aggregation was found in NAM added with ZnSO4, compared with ZnCl2. Zeta potential (ζ) analysis suggested that the surface of NAM added with ZnSO4 became less negatively charged, compared with that of ZnCl2 counterpart. Transmission electron microscopy showed that the structure of NAM was highly interconnected, finer and denser when zinc salts, especially ZnSO4 were incorporated. Therefore, ZnSO4 could be used to induce aggregation of fish muscle proteins, thereby improving gelling property of fish mince or surimi. [Copyright &y& Elsevier]

Mexican Panela cheeses manufactured with pasteurized cow's milk at a pilot plant scale were analyzed in order to determine the relationship between physicochemical and textural changes during 15-day storage. Changes in hardness, cohesiveness, springiness and chewiness were measured by texture profile analysis (TPA). Moisture, pH (superior and inferior rind and center) and total protein were evaluated with official methods. Proteolytic indexes (acid soluble nitrogen (ASN), non-protein nitrogen and 70% ethanol soluble nitrogen (EtOH-SN)) were obtained by selective precipitation and quantified by Kjeldahl method. Organic acids (lactic (LA), propionic (PA) and butyric acid (BA)) quantitation was done by high performance liquid chromatography. Analysis of variance (ANOVA) showed significant differences for all the physicochemical parameters evaluated, but only cohesiveness and springiness showed significant differences in texture parameters. By principal component analysis (PCA) two groups were separated, one from day 1 to 7 and one from day 9 to 15. [ABSTRACT FROM AUTHOR]

Pink discolouration is a problem faced in the squid processing industry, and some treatments have been implemented to tackle such a problem. The study aimed to elucidate the impact of NaCl in combination with oxidising agents on the quality changes of squid during frozen storage. The effects of treatment of pink squid using 3% ( w/ v) NaCl solution containing oxidising agents (0.05-0.5% ( w/ v) HO or 0-10 ppm NaOCl) on colour and chemical and physical changes of squid during frozen storage were investigated. The lowest decreases in a*, b* values, ∆ E* and ∆ C* of squid were obtained with the treatment using 3% NaCl solution containing 0.5% HO. Nevertheless, NaOCl (0-10 ppm) had no impact on a* and b* values. During frozen storage at −18 °C for 10 weeks, fresh squid, pink squid samples without and with treatments with 3% NaCl solution containing 0.5% HO had no changes in a* and b* values during frozen storage. Nevertheless, thiobarbituric acid reactive substances value, disulphide bond content, thaw drip and shear force were more pronounced in treated pink squid, compared with pink squid without treatment (control) and fresh squid, respectively, during the extended storage ( p < 0.05). Higher denaturation and aggregation of muscle proteins during frozen storage were observed in treated pink squid than that without treatment and fresh squid, respectively. Therefore, pink squid treated with oxidising agent was prone to protein aggregation and denaturation during the extended frozen storage, though it could lower the pink colour. Therefore, fresh squid without treatment using oxidising agent is recommended for production of frozen squid with negligible loss in quality during extended storage. [ABSTRACT FROM AUTHOR]

Abstract: Changes in natural actomyosin (NAM) from Pacific white shrimp (Litopenaeus vannamei) treated with sodium bicarbonate (NaHCO3) at different concentrations (0–1M) in the absence or the presence of 2.5% NaCl were studied. Turbidity of NAM solutions decreased with coincidental increase in solubility as the concentration of NaHCO3 increased. Surface hydrophobicity (SoANS) and total sulfhydryl content of NAM also increased when NaHCO3 concentration increased. Greater decreases in Ca2+- and Mg2+-ATPase activity were found in all NAM as NaHCO3 concentration increased, suggesting the denaturation of myosin head and the dissociation of actomyosin complex. The zeta potential (ζ) analysis suggested that the surface of NAM became more negatively charged (−12.12 to −26.98) as NaHCO3 concentration increased. Those changes were more intense in the presence of 2.5% NaCl. Transmission electron microscopy showed that the structure of actomyosin was more dissociated and lost the filamental structure when NaHCO3 at higher levels was used. [Copyright &y& Elsevier]

Abstract: The effect of wet and dry saltings on the physicochemical changes of tilapia (Oreochromis niloticus) muscle was investigated. Dry salting resulted in the higher rate of salt uptake into tilapia muscle facilitating the faster decrease in A w (p <0.05). The pH of both dry and wet salted fish muscles tended to decrease throughout the salting time and the lower pH was found in dry salted fish (p <0.05). The increase in the protein content in the salting medium was found during wet salted tilapia production (p <0.05). The TCA-soluble peptide content tended to decrease with increasing the salting time in both salting methods (p <0.05), suggesting a leaching effect of the salting medium or the exudative loss occurred in salted tilapia. Wet salting caused the greater formation of metmyoglobin in tilapia muscle when compared to dry salting at all time points (p <0.05) and the content of metmyoglobin increased as salting time increased in both salting methods (p <0.05). A lowered metmyoglobin with a lowered redness index of dry salted tilapia muscle was found, indicating the continuous oxidation of metmyoglobin to other hypervalent derivatives and hence the discolouration of salted tilapia. Lipid hydrolysis and oxidation of tilapia meat occurred with varying degrees in both salting methods and these changes depended on salting time. Dry salting resulted in a higher oxidation of tilapia muscle lipid as indicated by the higher PV and TBARS throughout the salting period when compared with that of wet salting (p <0.05). In conclusion, the physicochemical changes of tilapia muscle during salting are governed by the salting method and the salting time applied. [Copyright &y& Elsevier]

Abstract: Physicochemical changes, such as peel and flesh colours, total anthocyanin content, browning index, firmness, total soluble solid (TSS), titratable acidity (TA), sugar acid ratio (TSS/TA), antioxidant capacity, total phenolic content and ascorbic acid content, in fresh-cut Taaptimjan wax apple fruit stored at 4±2°C and 12±2°C for 7days were investigated. The skin of fresh-cut fruit stored at 4±2°C showed higher a ∗ value, chroma and total anthocyanin content and lower hue angle than those stored at 12±2°C. Lightness (L ∗ value) and whiteness index of the fresh-cut fruit flesh stored at 12±2°C showed significantly lower than those stored at 4±2°C which related to an significant increase in browning index. Firmness, total soluble solid, titratable acidity and sugar acid ratio did not significant changes during storage. Antioxidant capacity and total phenolic content increased throughout storage. Ascorbic acid content of the fresh-cut fruit stored at 4±2°C remained constant throughout storage whilst ascorbic content at 12±2°C decreased and was lower than that at 4±2°C. At 4±2°C antioxidant capacity and ascorbic acid content were higher than that stored at 12±2°C whilst there was no significant difference in total phenolic content. In conclusion, the reduction of whiteness index and the increase in browning index of fresh-cut wax apple flesh were the key factors affecting its quality and storage at 4±2°C could reduce the change in the flesh colour and maintained the peel colour and nutritional values of fresh-cut wax apple fruit during storage. [Copyright &y& Elsevier]

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Abstract: Mechanochemical-assisted extraction (MCAE) technique was developed for the efficient extraction of rutin from Hibiscus mutabilis L. This process was carried out via mechanochemical pretreatment in AGO-2 high intensity planetary mill. Highest yield of rutin was obtained by grinding H. mutabilis with Na2CO3 (15.0wt.%) and Na2B4O7·10H2O (1.5wt.%) for 4min, extraction temperature at 25°C, total extraction time of 15min (two cycles of 10min and 5min), acidification pH 5.0 and solvent/material ratio of 25mL/g. Scanning electron microscopy, X-ray powder diffraction and diffuse-reflectance UV–Vis spectrum were applied to identify the physicochemical property changes. These changes mainly included the enhanced diffusivity and water solubility of rutin resulting from the breakage of cell walls and its transformation into a water-soluble salt form by the mechanochemical pretreatment. Compared with heat reflux and superfine grinding extraction, MCAE showed the advantages of efficiency, no organic solvent consumption and much lower extraction temperature. Industrial relevance: In this study, mechanochemical-assisted extraction of rutin from H. mutabilis was developed and the physicochemical changes in this process were supervised. Owing to its great potential to transform the target compounds into water-soluble forms, MCAE provided a good alternative for efficient aqueous extraction of bioactive compounds, especially some poorly water-soluble natural products. [Copyright &y& Elsevier]

Abstract: The mechanisms of interactions in whey protein concentrate (WPC) texturized by reactive supercritical fluid extrusion and pH modifications were evaluated in terms of protein solubility in different extraction buffers, electrophoresis, free sulfhydryl (SH) groups, and apparent viscosity. The soluble protein content and free SH groups of the texturized WPC (tWPC) produced at pH 2.89 decreased by ∼20% and 16% relative to the unextruded control. It was completely soluble in the presence of urea and SDS, indicating the importance of non-covalent interactions in maintaining the structure of this product. Its dispersion (20% w/w) yielded a creamy texture with a particle size in the micron-range (mean diameter ∼5μm) and contributed ∼258 times higher viscosity compared to the unextruded control. The tWPC produced at pH 8.16 was soluble only in the presence of a reducing agent. It yielded a grainy texture with a high proportion of large particles due to an extensive aggregation via intermolecular disulfide formations. [Copyright &y& Elsevier]

The article presents a method of evaluating pyrotechnic compositions producing an acoustic effect. The aforementioned pyrotechnic compositions are used in firecrackers to simulate a cannon shot. Optimum compositions that were selected (Part I Evaluation of the applicability of mathematical models in developing pyrotechnic compositions producing an acoustic effect) for testing were evaluated for their explosive and physicochemical properties. The following methods were used to evaluate suitability: measurement of the sound intensity level, the burning rate, and sensitivity to mechanical stimuli—friction and flash fire temperature. In addition, a test concerning the change in the properties of pyrotechnic compositions during storage was also performed. [ABSTRACT FROM AUTHOR]

The objective of this work was to analyze the changes in the physicochemical and rheological characteristics of milk fortified with different calcium salts. Reconstituted milk samples using skim milk powder with different concentrations of calcium chloride and calcium lactate (0, 5 and 30 mmol kg−1) were obtained. Several physicochemical and rheometric techniques were used to analyze the effect of milk fortification. According to the results, all the applied techniques indicated that some of the added calcium migrates into the casein micelle forming colloidal calcium phosphate, and that the calcium added as lactate enters the micelles to a greater extent. A part of whey proteins would also be integrated into the micellar structure. An addition of 5 mmol kg−1 of calcium chloride and calcium lactate would be practically feasible, due to the mineral balance and the thermal stability that were not significantly affected at that concentration level. In conclusion, the results obtained with physicochemical techniques commonly used in literature are in agreement with those obtained in this study by rheometry, demonstrating that this simple and rapid technique allows inferring about the changes in mineral balance and effects on thermal stability when different salts are used for milk fortification. • Physicochemical characteristics and rheometry of calcium fortified milk. • Different calcium salts and concentrations were analyzed. • Rheometric method helps to evaluate the thermal stability. • Information that may help to improve calcium-fortified dairy formulations. [ABSTRACT FROM AUTHOR]

• Induction physicochemical changes in particles prepared by prolonged high-energy wet ball milling. • Conversion the applied oleic acid surfactant into a thin amorphous carbon layer on magnetic nanoparticles. • Mechanochemically activation Fe atoms in the NdFeB powder in the environment of ball milling. • The decomposition and transformation of OA molecules by Fe atoms with active surfaces. • Using more fatty acids rich in carbon atoms in wet ball milling, increasing permittivity, and shielding absorption efficiency. Fabrication and improvement of electromagnetic interference (EMI) shielding products have recently been the subject of intense research. In the present study, the NdFeB magnetic powder was used in prolonged high-energy wet ball milling to synthesize and enhance properties of the magnetic filler of EMI shielding composites. The physicochemical changes induced in particles prepared by the process confirmed that the applied oleic acid surfactant was simply converted into a thin amorphous carbon layer on NdFeB nanoparticles. Increasing the amount of surfactant in the ball milling procedure caused a thicker layer of the carbonaceous blend to be formed on magnetic nanoparticles. We found that the thicker layer of the amorphous carbon covering the synthesized magnetic particles increased the real and imaginary dielectric permittivity of the resulting product about 15% and 95%, respectively. This also increased the shielding absorption efficiency (SE A) about 40% and the total shielding efficiency (SE T) about 30% at some frequencies. Furthermore, more carbonaceous surfactant in composite (II) improved impedance matching, leading to a decrease in reflection loss and an increase in microwave absorption of the composite. [ABSTRACT FROM AUTHOR]