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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]

Study’s Excerpt • The physicochemical and microbiological properties of leachate from municipal solid waste (MSW) in Ikhueniro, Edo State, Nigeria was investigated. • Results revealed significant correlations between bacterial counts and the degradation of organic matter. • There is a need for improved waste management strategies in the area. Full Abstract Municipal solid waste (MSW) management in Nigeria faces significant challenges due to rapid urbanization and poor waste management practices. Leachate, the liquid generated from MSW, poses a major pollution threat to natural resources, including surface and groundwater, and adversely affects human health and hygiene. This study investigated the dynamics in physicochemical and microbiological properties of simulated leachate from dump site soil in Ikhueniro, Edo State, Nigeria using standard Microbiological testing techniques. Samples were collected from a non-sanitary open dumpsite in Ikhueniro, Edo State, Nigeria, and leachate was obtained by filtering 150 g of waste-impacted soil mixed with sterile distilled water (1000 mL). Over 28 days, microbial detection enumeration and physicochemical characterization were conducted on the filtrate leachate sample maintained in a rotary shaker at 28 °C and 150 rpm. Results indicated high densities of microbial contamination with total heterotrophic bacteria (1.5±0.5 to 6.9±1.0 × 104 CFUmL-1) and coliform (2.7±0.8 to 7.8±1.0 × 103 CFUmL-1) counts. These included potential pathogens like Klebsiella spp., Salmonella spp., Bacillus spp., Pseudomonas spp., and Yersinia spp. Physicochemical analyses revealed significant (p

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]

ABSTRACT: The changes occurring in soybean (SBO), sesame seed (SSO), almond (AO) and avocado (APO) oils during repeated frying cycles of potato chips were monitored. Potato chips were fried up to 5 cycles and the free fatty acid (FFA), peroxide value (PV), iodine value (IV), moisture, colour, smoke point and antioxidant properties of the oils at different frying cycles were assessed. SBO exceeded FFA limits after two cycles, while SSO and AO exceeded limits after four cycles. Moisture content of SBO, SSO and AO for first and second frying cycles was within acceptable limits. APO consistently exceeded FFA and moisture limits while PV of all oils remained within the permissible limit throughout the cycles. SBO and APO showed significant decreases in L* and b* values. Sesame seed oil displayed the highest reductions in phenolic content, flavonoid content, and antioxidant capacity, followed by avocado oil while almond oil exhibited the highest decline in total antioxidant, indicating a potential loss of antioxidant properties. These findings emphasize the detrimental impact of frying cycles on the physicochemical and antioxidant properties of these oils, raising concerns about their potential health benefits.

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]

It has been demonstrated that polyphenols have the potential to extend the shelf life of fish products. Thus, the effects of phenolic extracts from grape seed (GSE), lotus seedpod (LSPC), and lotus root (LRPE) were investigated in this study, focusing on the physicochemical changes and bacterial community of refrigerated channel catfish fillets during storage at 4 °C, using ascorbic acid (AA) as reference. As a result, GSE, LSPC, LRPE and AA inhibit the reproduction of microbials in catfish fillets during storage. According to the microbial community analysis, the addition of polyphenols significantly reduced the relative abundance of Proteobacterial in the early stage and changed the distribution of the microbial community in the later stage of storage. After 11 days of storage, the increase in total volatile base nitrogen (TVB-N) in fish was significantly reduced by 25.85%, 25.70%, 22.41%, and 39.31% in the GSE, LSPC, LRPE, and AA groups, respectively, compared to the control group (CK). Moreover, the lipid oxidation of samples was suppressed, in which thiobarbituric acid-reactive substances (TBARS) decreased by 28.77% in the GSE group, compared with the CK. The centrifugal loss, LF-NMR, and MRI results proved that GSE significantly delayed the loss of water and the increase in immobilized water flowability in catfish fillets. The polyphenol-treated samples also showed less decrease in shear force and muscle fiber damage in histology, compared to the CK. Therefore, the dietary polyphenols including GSE, LSPC, and LRPE could be developed as natural antioxidants to protect the quality and to extend the shelf life of freshwater fish. [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]

This study was conducted to investigate the visual appearance and physicochemical changes of postharvest jujube fruits (Ziziphus jujuba Mill. cv. Shucuizao) stored under 0 ℃ for 15 days. The fruits were dipped in 0 (control), 50, 100, 200 and 400 μM melatonin solutions after harvest. The results showed that treatment with a suitable melatonin concentration improved the rate of crisp fine fruits, delayed weight loss and firmness decline, and suppressed changes in total soluble solids (TSS) and titratable acidity (TA) contents of jujube fruits compared with the control. In addition, jujube fruits soaked with melatonin showed improved antioxidant capacity through increased ascorbic acid (AsA) content, enhanced superoxide dismutase (SOD) activity, and decreased malonaldehyde (MDA) content. As a result, 50 μM melatonin showed the greatest improvement of visual appearance and quality maintenance, and could be used as an effective treatment to preserve postharvest jujube fruit. [ABSTRACT FROM AUTHOR]

This paper focuses on the effect of malondialdehyde-induced oxidative modification (MiOM) on the gel properties of duck myofibrillar proteins (DMPs). DMPs were first prepared and treated with oxidative modification at different concentrations of malondialdehyde (0, 0.5, 2.5, 5.0, and 10.0 mmol/L). The physicochemical changes (carbonyl content and free thiol content) and gel properties (gel whiteness, gel strength, water holding capacity, rheological properties, and microstructural properties) were then investigated. The results showed that the content of protein carbonyl content increased with increasing MDA oxidation (p < 0.05), while the free thiol content decreased significantly (p < 0.05). Meanwhile, there was a significant decrease in gel whiteness; the gel strength and water-holding capacity of protein gels increased significantly under a low oxidation concentration of MDA (0–5 mmol/L); however, the gel strength decreased under a high oxidation concentration (10 mmol/L) compared with other groups (0.5–5 mmol/L). The storage modulus and loss modulus of oxidized DMPs also increased with increasing concentrations at a low concentration of MDA (0–5 mmol/L); moreover, microstructural analysis confirmed that the gels oxidized at low concentrations (0.5–5 mmol/L) were more compact and homogeneous in terms of pore size compared to the high concentration or blank group. In conclusion, moderate oxidation of malondialdehyde was beneficial to improve the gel properties of duck; however, excessive oxidation was detrimental to the formation of dense structured gels. [ABSTRACT FROM AUTHOR]

This paper focuses on the changes of physicochemical properties and gel-forming ability of duck myofibrillar proteins (DMPs) induced using hydroxyl radical oxidizing systems. DMPs were firstly extracted and then oxidized at various H2O2 concentrations (0, 4, 8, and 12 mmol/L) using Fenton reagent (Fe3+-Vc-H2O2) to generate hydroxyl radicals, and the effects of hydroxyl radical oxidation on the physicochemical changes and heat-induced gel-forming capacity of DMPs were analyzed. We observed obvious increases in the carbonyl content (p < 0.05) and surface hydrophobicity of DMPs with increasing of H2O2 concentrations (0–12 mmol/L). In contrast, the free thiol content (p < 0.05) and water retention ability of DMPs decreased with increasing H2O2 concentrations (0–12 mmol/L). These physicochemical changes suggested that high concentrations of hydroxyl radicals significantly altered the biochemical structure of DMPs, which was not conducive to the formation of a gel mesh structure. Furthermore, the gel properties were reduced based on the significant decrease in the water holding capacity (p < 0.05) and increased transformation of immobilized water of the heat-induced gel to free water (p < 0.05). With the increase of H2O2 concentrations, secondary structure of proteins analysis results indicated α-helix content decreased significantly (p < 0.05), however, random coil content increased (p < 0.05). And more cross-linked myosin heavy chains were detected at higher H2O2 concentrations groups through immunoblot analysis (p < 0.05). Therefore, as H2O2 concentrations increased, the gel mesh structure became loose and porous, and the storage modulus and loss modulus values also decreased during heating. These results demonstrated that excessive oxidation led to explicit cross-linking of DMPs, which negatively affected the gel-forming ability of DMPs. Hence, when processing duck meat products, the oxidation level of meat gel products should be controlled, or suitable antioxidants should be added.

Mexico produces 30 790.7 t per year of soursop fruits (FG), Nayarit contributes 75.4 %. The FG are perishable, it is proposed to develop edible coatings (RC). The objective was to evaluate CR based on starch (2 %) of FG (2 % w/v) in FG stored at 15 ± 2 °C and 22 ± 2 °C. Weight loss PP (%), firmness F (N), titratable acidity AT (%), total soluble solids TSS (°Brix) and color (L*C*H) were evaluated. Treatment design: FG without CR at 22 ± 2 °C for 8 d (T1), FG with CR at 22 ± 2 °C for 10 d (T2) and FG without CR (T3) and FG with CR at 15 ± 2 °C for 4 d and subsequently transferred to 22 ± 2 °C for 8 d (T4), RH 90%. The PP was 10.3 (T1) and 6.1(T2), F of 45.9 (T1) and 26.2 (T2), at the end of storage AT of 0.94 (T1) and 0.56 (T2) and SST of 15.8 (T1) and 15.5 (T2). At T3 and T4, PP was 10.5 and 10.4, respectively, F was 9.6 (T3, 8 d) and 19 (T4, 10 d), AT was 0.26 (T3) and 0.27 (T4), SST was 12.2 (T3) and 11.4 (T4) at the end of storage. The fruits of T4 presented a green color with low luminosity (L: 43.9 C: 15.5 H: 105) at the end of storage. The fruits of T2 presented less loss of weight and firmness, high concentration of TSS at 4 d of storage. The coating does not affect the fruits stored in both storage conditions. [ABSTRACT FROM AUTHOR]

Rapid diversification is a way of responding to environmental change for freshwater organisms. This work examined the physicochemical changes and abundance of freshwater snails in Anambra River (Nigeria) during the rainy season. Field studies were conducted fortnightly from June to August 2019 at three stations of the river namely: Otuocha (station I), Otunsugbe (station II), and Ukwubili (station III) about 8.35 kilometers apart from each other. A scoop net of 2 cm mesh size and handpicking was used to sample freshwater snails randomly and water samples were taken to the laboratory for physicochemical analysis. A total of 896 freshwater snails belonging to 6 species (Afropomus balanoidea, Pomacea maculata, Lymnea stagnalis, Lanistes ovum, Pila wernei, and Saulea vitrea) were collected. Pomacea maculata was the most dominant species with a relative abundance of 45.87 %, while Saulea vitrea was the least dominant species with a relative abundance of 2.34 %. There was a significant negative correlation between dissolved oxygen and Pomacea maculate (r = –0.877, p = 0.002) and a positive correlation between dissolved oxygen and Stagnalis lymnea (r = 0.840, p = 0.005). The diversity of species was highest at Otuocha (1.171) followed by Ukwubili (1.133) and Otunsugbe (0.856) with average mean temperatures of (23.1 ±0.1) °C, (27.30 ±0.00) °C, and (26.80 ±0.03) °C respectively. The distribution of freshwater snails was influenced by the physicochemical variability of Anambra River during the rainy season. Therefore, further studies for a longer time and different seasons to examine the impact of physicochemical changes on the snail distribution are encouraged. [ABSTRACT FROM AUTHOR]

It has been demonstrated that polyphenols have the potential to extend the shelf life of fish products. Thus, the effects of phenolic extracts from grape seed (GSE), lotus seedpod (LSPC), and lotus root (LRPE) were investigated in this study, focusing on the physicochemical changes and bacterial community of refrigerated channel catfish fillets during storage at 4 °C, using ascorbic acid (AA) as reference. As a result, GSE, LSPC, LRPE and AA inhibit the reproduction of microbials in catfish fillets during storage. According to the microbial community analysis, the addition of polyphenols significantly reduced the relative abundance of Proteobacterial in the early stage and changed the distribution of the microbial community in the later stage of storage. After 11 days of storage, the increase in total volatile base nitrogen (TVB-N) in fish was significantly reduced by 25.85%, 25.70%, 22.41%, and 39.31% in the GSE, LSPC, LRPE, and AA groups, respectively, compared to the control group (CK). Moreover, the lipid oxidation of samples was suppressed, in which thiobarbituric acid-reactive substances (TBARS) decreased by 28.77% in the GSE group, compared with the CK. The centrifugal loss, LF-NMR, and MRI results proved that GSE significantly delayed the loss of water and the increase in immobilized water flowability in catfish fillets. The polyphenol-treated samples also showed less decrease in shear force and muscle fiber damage in histology, compared to the CK. Therefore, the dietary polyphenols including GSE, LSPC, and LRPE could be developed as natural antioxidants to protect the quality and to extend the shelf life of freshwater fish.

Vacuum impregnation (VI) has been immensely used in modifying the physicochemical properties, nutritional values and sensory attributes of fruits and vegetables. However, the metabolic consequences of the plant tissue upon impregnation have not been profoundly explored although shelf life is strongly dependent on this factor. In this study, spinach leaves were impregnated with salicylic acid (SA), γ-aminobutyric acid (GABA) and sucrose to improve its quality and storage ability by reducing the chilling injury through the improvement of proline content. The spinach leaves were stored at 4 °C for 7 days and were analyzed at 12 h interval. Upon 1 day of impregnation, the proline content in GABA, sucrose and SA impregnated leaves was increased by 240%, 153% and 103%, respectively, while in non-impregnated leaves, the proline content was decreased by 23.8%. The chlorophyll content of GABA impregnated leaves exhibited the lowest reduction (49%) followed by sucrose (55%) and SA (57%); meanwhile, non-impregnated leaves reduced 80% of chlorophyll content at the end of storage. Sensory evaluation showed that GABA, sucrose and SA impregnated leaves respectively, obtained higher score in terms of freshness, color, texture and overall appearance as compared to non-impregnated leaves. [ABSTRACT FROM AUTHOR]

This paper focuses on the effect of malondialdehyde-induced oxidative modification (MiOM) on the gel properties of duck myofibrillar proteins (DMPs). DMPs were first prepared and treated with oxidative modification at different concentrations of malondialdehyde (0, 0.5, 2.5, 5.0, and 10.0 mmol/L). The physicochemical changes (carbonyl content and free thiol content) and gel properties (gel whiteness, gel strength, water holding capacity, rheological properties, and microstructural properties) were then investigated. The results showed that the content of protein carbonyl content increased with increasing MDA oxidation (p < 0.05), while the free thiol content decreased significantly (p < 0.05). Meanwhile, there was a significant decrease in gel whiteness; the gel strength and water-holding capacity of protein gels increased significantly under a low oxidation concentration of MDA (0–5 mmol/L); however, the gel strength decreased under a high oxidation concentration (10 mmol/L) compared with other groups (0.5–5 mmol/L). The storage modulus and loss modulus of oxidized DMPs also increased with increasing concentrations at a low concentration of MDA (0–5 mmol/L); moreover, microstructural analysis confirmed that the gels oxidized at low concentrations (0.5–5 mmol/L) were more compact and homogeneous in terms of pore size compared to the high concentration or blank group. In conclusion, moderate oxidation of malondialdehyde was beneficial to improve the gel properties of duck; however, excessive oxidation was detrimental to the formation of dense structured gels.

In Cameroon, alcoholic beverages represent one of the main consumed drinks. In northern regions, indigenous sorghum beers are very popular and widely consumed in an actively fermenting state by people. In this study, some physicochemical parameters of alcoholic sorghum beverages and correlations between them were evaluated during fermentation for 10 days. The indigenous white and red beers were produced at the laboratory scale assisted by experimental producers and some parameters (pH, total acidity, alcohol, sugars, density, total solids, temperature, and conductivity) were measured on the wort and fermented beverages. The pH decreased from 3.2 to 2.4 and 3.11 to 2.41; total acidity increased from 1.07 to 5.1 g/L and 0.5 to 4.6 g/L; alcohol was enhanced from 0 to 9.5% and 0 to 6.8% (v/v); total solids dropped from 13.6 to 5°P and 12.2 to 3.3°P, respectively, in the white and red sorghum beers. The multivariate analysis showed a good correlation between consumption of sugar, the decrease in total solids and density with the decrease in pH. Additionally, it was shown that a perfect link exists between the production of alcohol and organic acids. The hierarchical analysis showed that indigenous red beer samples fermented for one and two days and those fermented for four to 10 days were related and could be separate in two distinct groups, whereas white turbid beer samples were separated in three different groups, those fermented for one to four days, five to six days, and seven to 10 days. The results obtained could serve as a guide to better understand the fermentation process of indigenous alcoholic sorghum-based beverages. [ABSTRACT FROM AUTHOR]

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.

Vacuum impregnation (VI) has been immensely used in modifying the physicochemical properties, nutritional values and sensory attributes of fruits and vegetables. However, the metabolic consequences of the plant tissue upon impregnation have not been profoundly explored although shelf life is strongly dependent on this factor. In this study, spinach leaves were impregnated with salicylic acid (SA), γ-aminobutyric acid (GABA) and sucrose to improve its quality and storage ability by reducing the chilling injury through the improvement of proline content. The spinach leaves were stored at 4 °C for 7 days and were analyzed at 12 h interval. Upon 1 day of impregnation, the proline content in GABA, sucrose and SA impregnated leaves was increased by 240%, 153% and 103%, respectively, while in non-impregnated leaves, the proline content was decreased by 23.8%. The chlorophyll content of GABA impregnated leaves exhibited the lowest reduction (49%) followed by sucrose (55%) and SA (57%); meanwhile, non-impregnated leaves reduced 80% of chlorophyll content at the end of storage. Sensory evaluation showed that GABA, sucrose and SA impregnated leaves respectively, obtained higher score in terms of freshness, color, texture and overall appearance as compared to non-impregnated leaves.

In Cameroon, alcoholic beverages represent one of the main consumed drinks. In northern regions, indigenous sorghum beers are very popular and widely consumed in an actively fermenting state by people. In this study, some physicochemical parameters of alcoholic sorghum beverages and correlations between them were evaluated during fermentation for 10 days. The indigenous white and red beers were produced at the laboratory scale assisted by experimental producers and some parameters (pH, total acidity, alcohol, sugars, density, total solids, temperature, and conductivity) were measured on the wort and fermented beverages. The pH decreased from 3.2 to 2.4 and 3.11 to 2.41; total acidity increased from 1.07 to 5.1 g/L and 0.5 to 4.6 g/L; alcohol was enhanced from 0 to 9.5% and 0 to 6.8% (v/v); total solids dropped from 13.6 to 5°P and 12.2 to 3.3°P, respectively, in the white and red sorghum beers. The multivariate analysis showed a good correlation between consumption of sugar, the decrease in total solids and density with the decrease in pH. Additionally, it was shown that a perfect link exists between the production of alcohol and organic acids. The hierarchical analysis showed that indigenous red beer samples fermented for one and two days and those fermented for four to 10 days were related and could be separate in two distinct groups, whereas white turbid beer samples were separated in three different groups, those fermented for one to four days, five to six days, and seven to 10 days. The results obtained could serve as a guide to better understand the fermentation process of indigenous alcoholic sorghum-based beverages.

Aim: The present study evaluated the structural changes resulting from the interaction between a recombinant influenza A virus M2 protein and aluminum hydroxide adjuvant to investigate the antigen for further immunological studies. Materials & methods: Membrane protein II was produced from the H1N1 subtype of human influenza A virus. The interaction between M2 protein and alum inum hydroxide adjuvant was evaluated by physicochemical techniques including scanning electron microscope, UV-Vis spectra, Fourier-transform infrared spectroscopy and circular dichroism spectroscopy. Results: Physicochemical methods showed high-level protein adsorption and accessibility to the effective parts of the protein. Conclusion: It was concluded that M2 protein secondary structural perturbations, including the α-helix-to-β-sheet transition, enhanced its mechanical properties toward adsorption. [ABSTRACT FROM AUTHOR]

Pulses (grain legumes) are increasingly of interest to the food industry as product formulators and consumers seek to exploit their fiber‐rich and protein‐rich reputation in the development of nutritionally attractive new products, particularly in the bakery, gluten‐free, snack, pasta, and noodle categories. The processing of pulses into consistent high‐quality ingredients starts with a well‐defined and controlled milling process. However, in contrast to the extensive body of knowledge on wheat flour milling, the peer‐reviewed literature on pulse flour milling is not as well defined, except for the dehulling process. This review synthesizes information on milling of leguminous commodities such as chickpea (kabuli and desi), lentil (green and red), pea, and bean (adzuki, black, cowpea, kidney, navy, pinto, and mung) from the perspective of a wheat miller to explore the extent to which pulse milling studies have addressed the objectives of wheat flour milling. These objectives are to reduce particle size (so as to facilitate ingredient miscibility), to separate components (so as to improve value and/or functionality), and to effect mechanochemical transformations (for example, to cause starch damage). Current international standards on pulse quality are examined from the perspective of their relationship to the millability of pulses (that is, grain legume properties at mill receival). The effect of pulse flour on the quality of the products they are incorporated in is examined solely from the perspective of flour quality not quantity. Finally, we identify research gaps where critical questions should be answered if pulse milling science and technology are to be established on par with their wheat flour milling counterparts. [ABSTRACT FROM AUTHOR]

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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]

"Nixtamalization" causes in corn grain physical, chemical and rheological changes that affect the quality of the dough and tortilla. The traditional corn nixtamalization, carried out mostly in open containers, presents a very poor utilization of the energy required for this process, as it can take up to 70 % more of the fuel required. The correct selection of corns for nixtamalization contributes to the quality of tortillas and fuel saving. The aim of this study was to determine the physical, chemical, and thermal changes that occur during nixtamalization of corn grain varieties with different degrees of hardness and its relation to fuel consumption and energy demand during the process. Fuel consumption and physical and chemical changes in the grain and the cooking water or "nejayote" were monitored during the alkaline cooking of five varieties of corn. In the nejayote, pH values decreased after alkaline cooking in an average of 0.2 units. Cooking time was 26.6, 31.6, 36.6, 31.6, and 38.3 min, with gas consumption of 112.6, 119.2, 125.9, 119.2, and 128.1 g for the varieties Criollo, Mont265, Mont360, Mont363 and Mont41 respectively. Grains of lower hardness, absolute density and test weight required the least amount of fuel for nixtamalization. The rheological properties of flour during nixtamalization had similar behavior except Mont265 variety whose grains are smaller. The thermal properties of flour were similar after an increase in the gelatinization temperature of the samples taken at the end of nixtamalization. It is concluded that besides determining the quality characteristics of the dough and tortillas produced, it is necessary to know the energy parameters required for the nixtamalization of the of the corn varieties. [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]

Almost the entire metallurgical grade alumina is produced from bauxite using the Bayer process. The leaching conditions in Bayer process depend on various Al-oxyhydroxide minerals/phases present in the bauxite. Among the various bauxite types, gibbsitic (trihydrate) bauxite is easiest to digest. Monohydrate (boehmitic and diasporic) bauxites need more stringent digestion conditions in terms of temperature, pressure and alkali concentration. Mechanical activation during milling, especially high energy milling, results in enhanced reactivity of solids due to physicochemical changes induced by milling. This paper is an overview of our recent research on mechanical activation of bauxite and its constituent phases, gibbsite and boehmite. This paper focuses on the leaching of mechanically activated bauxite ores. Complementary results on mechanical activation of gibbsite and boehmite phases are included for a deeper understanding of mechanical activation of bauxite. Implications of these results are highlighted in the context of the Bayer process. [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]