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1.
Molecules ; 27(8)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35458795

RESUMO

Peaches are grown in many Egyptian orchards for local and global fresh market sales. The interior fruit tissue breakdown (IFTB), often resulting in decayed peaches, is a severe problem during marketing. Therefore, to minimize FTB of peaches, in this study, gum arabic (GA) and polyvinylpyrrolidone (PVP) were mixed with different concentrations of salicylic acid (SA) (0, 1, and 2 mM) and were applied as edible coating to extend the shelf life of peach fruits. Mature peaches were selected and harvested when peaches reached total soluble solid content (SSC: 8.5%) and fruit firmness of about 47 N. Fruits were coated and stored at room temperature (26 ± 1 °C and air humidity 51 ± 1%) for 10 days during two seasons: 2020 and 2021. Fruit coated with GA/PVP-SA 2 mM showed a significant (p < 0.05) inhibition in degrading enzyme activities (CWDEs), such as lipoxygenase (LOX), cellulase (CEL), and pectinase (PT), compared to uncoated and coated fruits during the shelf-life period. Hence, cell wall compartments were maintained. Consequently, there was a reduction in browning symptoms in fruits by inhibiting polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) activities. Thus, the fruit skin browning index showed almost no symptoms. The lipid peroxidation process and ionic permeability declined as well. The result suggests that, by applying GA/PVP-SA 2 mM as an edible coating, fruit tissue breakdown can be minimized, and the shelf life of peach can be extended up to 10 days without symptoms of tissue breakdown.


Assuntos
Prunus persica , Frutas/metabolismo , Goma Arábica , Povidona , Ácido Salicílico/metabolismo
2.
Indian J Thorac Cardiovasc Surg ; 40(2): 142-150, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38389769

RESUMO

Background: Aortic stenosis (AS) is a well-known cause of mortality. We aimed to assess the prognostic value of high-sensitive troponin T (hs-TnT) in symptomatic patients with severe AS and preserved left ventricular ejection fraction (LVEF) after surgical aortic valve replacement (AVR). Patients and methods: The study recruited patients with severe symptomatic AS fulfilling the inclusion criteria in the period between April 2020 and February 2022. Comprehensive echocardiography was done. The following parameters were assessed: AS severity, LV mass index (LVMI), left atrium volume index (LAVI), and LVEF. E/e' and LVEF were calculated using the biplane method of Simpsons. Global longitudinal strain (GLS) was assessed by speckle tracking echocardiography. Peripheral blood samples were collected for hs-TnT measurement. All patients underwent surgical AVR. The patients were followed for the following 6 months for major adverse cardiovascular events (MACE). MACE was defined as cardiac death, re-admission for congestive heart failure (CHF) and fatal arrhythmia. Results: One hundred and eight patients (mean age = 58.7 ± 7.68 years) with severe AS were recruited. Seventeen patients presented with MACE including 8 cardiac deaths. We divided the patients into two groups based on the normal hs-TnT values. The Kaplan-Meier curve revealed a statistically significant difference in MACE rate among troponin groups (log-rank test = 5.06, p = 0.025). There was significant difference between both groups regarding GLS with smaller GLS in negative hs-TnT group. In multivariate analysis, GLS and hs-TnT were significantly associated with MACE (p = 0.022 and < 0.01 respectively). The cutoff value of hs-TnT of 238.25 had a sensitivity of 70% and a specificity of 81% for predicting future MACE. There was a significant correlation between GLS and troponin (p < 0.001). Conclusions: hs-TnT is associated with bad short-term prognosis after AVR. hs-TnT and GLS could be significant predictors for future MACE in patients with severe symptomatic AS and preserved LVEF who underwent AVR. Elevated hs-TnT and impaired GLS could set an indication of early intervention in asymptomatic severe AS.

3.
Foods ; 13(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38275715

RESUMO

Human milk lipids generally have the maximum long-chain fatty acids at the sn-2 position of the glycerol backbone. This positioning makes them more digestible than long-chain fatty acids located at the sn-1, 3 positions. These unique fatty acid distributions are not found elsewhere in nature. When lactation is insufficient, infant formula milk has been used as a substitute. However, the distribution of most fatty acids ininfant formula milk is still different from human milk. Therefore, structured lipids were produced by the redistribution of medium-chain fatty acids from commercial butterfat (CBF) and n-3 and n-6 long-chain fatty acids from skipjack tuna eyeball oil (STEO). Redistribution was carried out via transesterification facilitated by Asian seabass liver lipase (ASL-L). Under the optimum conditions including a CBF/STEO ratio (3:1), transesterification time (60 h), and ASL-L unit (250 U), the newly formed modified-STEO (M-STEO) contained 93.56% triacylglycerol (TAG), 0.31% diacylglycerol (DAG), and 0.02% monoacylglycerol (MAG). The incorporated medium-chain fatty acids accounted for 18.2% of M-STEO, whereas ASL-L could incorporate 40% of n-3 fatty acids and 25-30% palmitic acid in M-STEO. The 1H NMRA and 13CNMR results revealed that the major saturated fatty acid (palmitic acid) and unsaturated fatty acids (DHA and EPA) were distributed at the sn-2 position of the TAGs in M-STEO. Thus, M-STEO enriched with medium-chain fatty acids and n-3 fatty acids positioned at the sn-2 position of TAGs can be a potential substitute for human milk fatty acids in infant formula milk (IFM).

4.
Ultrason Sonochem ; 108: 106949, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39003930

RESUMO

Investigating the extraction of bioactive compounds represents a hopeful direction for maximizing the value of longan fruit byproducts. This study explored the influence of ultrasonic-assisted extraction (UAE) parameters-specifically ultrasonic power ratios, temperatures, and exposure times-utilizing water as a green solvent on several properties of the longan seeds extract (LSE). These properties encompassed the energy consumption of the UAE process (EC), extraction yield (EY), total phenolic contents (TPC), total flavonoid contents (TFC), and antioxidant activity (DPPH). Additionally, the study sought to optimize the conditions of UAE process and examine its thermodynamic properties. A three-level, three-factor full factorial design was utilized to assess the effects of different factors on LSE properties. Results indicated that EC, EY, TPC, TFC, and DPPH were significantly influenced by power ratios, temperatures, and exposure time. Moreover, the proposed models effectively characterized the variations in different properties during the extraction process. The optimized extraction conditions, aimed at minimizing EC while maximizing EY, TPC, TFC, and DPPH radical scavenging activity, were demonstrated as an ultrasonic power ratio of 44.4 %, a temperature of 60 °C, and an extraction time of 17.7 min. Optimization led to 563 kJ for EC, 7.85 % for EY, 47.21 mg GAE/mL for TPC, 96.8 mg QE/mL for TFC, and 50.15 % for DPPH radical scavenging activity. The results emphasized that the UAE process exhibited characteristics of endothermicity and spontaneity. The results provide valuable insights that could inform the enhancement of extraction processes, potentially benefiting industrial utilization and pharmaceutical formulations.


Assuntos
Antioxidantes , Fracionamento Químico , Pós , Sementes , Ondas Ultrassônicas , Sementes/química , Cinética , Fracionamento Químico/métodos , Antioxidantes/isolamento & purificação , Antioxidantes/química , Temperatura , Fenóis/isolamento & purificação , Fenóis/química , Flavonoides/isolamento & purificação , Flavonoides/química , Sonicação/métodos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
5.
Foods ; 12(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37628023

RESUMO

Convection drying in combination with ultrasound pretreatment has emerged as a promising technology for seafood manufacturing. The primary objective of this research was to model the mass transfer process of Asian seabass (Lates calcarifer) fish skin without and with ultrasound pretreatment during convection drying at different temperatures (45, 55, and 65 °C). Additionally, the study aimed to examine the impact of ultrasound pretreatment and temperatures on the drying characteristics and specific energy consumption for drying of Asian seabass fish skin. Seven semi-theoretical models, namely Lewis, Page, modified Page, Vega-Lemus, Verma, Henderson and Pabis, and two-term models, were employed to characterize the moisture transfer process. The results of the study indicated a decrease in the moisture content as the drying time increased at different drying temperatures. Higher drying temperatures were associated with an increased drying rate. Among the mathematical models tested, the modified Page model provided a satisfactory description of the thin-layer drying characteristics of fish skin. Fick's law of diffusion was utilized to determine the effective moisture diffusivities. Comparing the drying of fish skin without (SS) and with ultrasound pretreatment (US-SS), the drying of the latter generally showed higher Deff values. The temperature dependence of the effective diffusivity coefficient was well described by the Arrhenius-type model. An increase in the drying temperature resulted in an increment of the effective moisture diffusivity. In general, the skin pretreated using ultrasound had a reduced drying time, by up to 28%. Additionally, this approach contributed to an approximate 22% reduction in the specific energy consumption, concurrently enhancing the energy efficiency. The microstructure analysis showed that fresh and dried US-SS samples had a more open structure and higher porosity, in comparison to the corresponding SS samples. These findings contribute to the knowledge on the application of ultrasound as the pretreatment of fish skin before drying and provide valuable insights for the development of potential drying techniques in the seafood industry.

6.
Foods ; 13(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38201120

RESUMO

Moisture adsorption and desorption isotherms of gelatin extracted from whitefish skin powder (FSGP) at different temperatures across a wide range of water activity were determined along with their thermodynamic properties. Nine mathematical models were utilized for fitting the experimental data and simulating the adsorption and desorption behavior. The thermodynamic properties were determined and fitted to the experimental data. The results showed that Peleg and GAB models were the best fit for FSGP. The energies involved in the adsorption and desorption process of FSGP indicated a stronger dependence on equilibrium moisture content (Xe). When Xe decreased, there was a consistent trend of increasing thermodynamic properties. Both the moisture adsorption and desorption behaviors of FSGP were, therefore, non-spontaneous processes. Linear correlations between the changes in enthalpy and entropy for adsorption and desorption were observed, indicating the presence of enthalpy-entropy compensation for FSGP. For preserving FSGP quality, it should be stored with Xw ≤ 8 (gw/gdm, d.b.) at temperatures below 53 °C and an RH of 50% to avoid it becoming rubbery. These findings are crucial for providing insight into the optimal drying and storage conditions.

7.
Gels ; 9(6)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37367158

RESUMO

Applying energy supplements in gel form may circumvent gastric discomfort and thus it is a practical alternative. The main objective of this investigation was to develop date-based sports energy gels consisting of highly nutritious ingredients such as black seed (Nigella sativa L.) extract and honey. Three date cultivars (Sukkary, Medjool, and Safawi) were used and characterized for their physical and mechanical properties. The sports energy gels were prepared with addition of xanthan gum (0.5% w/w) as the gelling agent. The newly developed date-based sports energy gels were then analysed for proximate composition, pH level, colour, viscosity, and texture profile analysis (TPA). A sensory test was also conducted with 10 panellists who analysed the appearance, texture, odour, sweetness, and overall acceptability of the gel using a hedonic scale. The results showed that different types of date cultivars affect the physical and mechanical properties of the new developed gels. The outputs of the sensory evaluation revealed that the date-based sports energy gel prepared from Medjool received the highest mean score, followed closely by those prepared from Safawi and Sukkary, indicating that, overall, all three cultivars are acceptable to consumers, but the date-based sports energy gel prepared from Medjool is the most preferred one.

8.
Materials (Basel) ; 16(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36614726

RESUMO

The transverse cracking behavior of a carbon-fiber-reinforced plastic (CFRP) cross-ply laminate is investigated using a fatigue test and an entropy-based failure criterion in this study. The results of fatigue experiments show that the crack accumulation behavior depends on the cyclic number level and frequency, in which two obvious transverse cracks are observed after 104 cyclic loads and 37 transverse cracks occur after 105 cycles. The final numbers of transverse cracks decrease from 29 to 11 when the load frequency increases from 5 Hz to 10 Hz. An entropy-based failure criterion is proposed to predict the long-term lifetime of laminates under cyclic loadings. The transverse strength of 90° ply is approximated by the Weibull distribution for a realistic simulation. Progressive damage and transverse cracking behavior in CFRP ply can be reproduced due to entropy generation and strength degradation. The effects of stress level and load frequency on the transverse cracking behavior are investigated. It is discovered that, at the edge, the stress σ22 + σ33 that is a dominant factor for matrix tensile failure mode is greater than the interior at the first cycle load, and as stress levels rise, a transverse initial crack forms sooner. However, the initial transverse crack initiation is delayed as load frequencies increase. In addition, transverse crack density increases quickly after initial crack formation and then increases slowly with the number of load cycles. The proposed method's results agree well with those of the existing experimental method qualitatively. In addition, the proposed entropy-based failure criterion can account for the effect of load frequency on transverse crack growth rate, which cannot be addressed by the well-known Paris law.

9.
Sci Rep ; 11(1): 6031, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33727666

RESUMO

Agaricus bisporus is an edible fungus with a limited shelf life due to high moisture loss, browning, respiration, self-dissolve, lack of physical protection, rotting, and microbial attack. Mushrooms have been coated with nisin, nano-silica, and chitosan films in order to extend the shelf life, preserve quality and oxidation activities. The results showed that treating the mushrooms with chitosan and nano-silica (CH-AN-SILICA) increased superoxide dismutase activity (SOD-6.53 U kg-1), total phenolic content (TPC-0.39 g kg-1), and malondialdehyde content (MDA-1.63 µmol kg-1). CH-AN-SILICA treatment exhibited the highest scavenging against 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals. While, CH-AN-SILICA with the addition of nisin as an antimicrobial agent preserved almost the reactive oxygen species such as hydroxyl radicals (OH-0.33 µmol g-1), superoxide anion (O2•--0.271 mmol s-1 kg-1), and hydrogen peroxide (H2O2-21.54 µmol g-1). Besides, both CH-AN-SILICA and CH-AN-SILICA/N enhanced the catalase (CAT) activity and reduced the respiration rate. The results indicated that the combination of nisin, nano-silica, and chitosan coating films was effective in providing a longer storage life with acceptable quality in mushrooms.

10.
Foods ; 10(11)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34828848

RESUMO

Air-frying is an innovative technique for food frying that uses hot air circulation to prepare healthy products. The objectives of this study were to establish simplified models to reflect the efficacy of the air frying process at varying temperatures and times on the quality attributes of falafel, and to optimize the frying conditions for producing air-fried falafel. Moisture content, color, fat content, hardness, and sensory evaluation of the fried falafel were analyzed under varied temperatures (140 °C, 170 °C, and 200 °C) and time periods (5 min, 10 min, and 15 min). Statistical analysis was then applied to obtain the best fit model that can describe the properties of fried falafel. Results indicated that moisture content, fat content, and L*-value of air-fried falafel were adversely related to the frying temperature and time, but the hardness and ΔE of fried falafel were increased as the frying temperature and time increased. Moreover, an increase followed by a decrease was shown for the appearance, aroma, crispness, taste, and overall preference scores with the increase in frying temperature and time. The regression analysis showed that the proposed models could be properly used for predicting the properties of the fried falafel. In addition, the overlaid plots resulted in the optimum frying temperature of 178.8 °C and time of 11.1 min. Interestingly, the fat content of the air-fried falafel reduced by 45% at optimal frying conditions compared with that for the deep-fat fried one at 180 °C for 7 min (control). In comparison, the air-fried falafel was lower in fat content, higher in hardness with more acceptable appearance and crispness scores than deep-fat fried falafel. Such information could be beneficial to the manufacturers of the falafel to produce an optimal and healthy product.

11.
Sci Rep ; 11(1): 7915, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846473

RESUMO

White button mushrooms are greatly high perishable and can deteriorate within a few days after harvesting due to physicomechanical damage, respiration, microbial growth of the delicate epidermal structure. For that reason, the present research work was applied to evaluate the effect of chitosan combination with nano-coating treatments on physicochemical parameters and microbial populations on button mushrooms at chilling storage. Nano coating with the addition of nisin 1% (CHSSN/M) established the minimum value for weight loss 12.18%, maintained firmness 11.55 N, and color index profile. Moreover, O2% rate of (CHSSN/M) mushrooms was the lowest at 1.78%; while the highest rate was reported for CO2 24.88% compared to the untreated samples (Control/M) on day 12. Both pH and total soluble solid concentrations increased during storage. Results reported that the (CHSS/M) mushroom significantly (P < 0.05) reduced polyphenol oxidase activity (24.31 U mg-1 Protein) compared with (Control/M) mushrooms that increased faster than the treated samples. (CHSSN/M) treatment was the most efficient in the reduction of yeast and mold, aerobic plate microorganisms (5.27-5.10 log CFU/g), respectively. The results established that nano-coating film might delay the aging degree and accompany by marked prolongation of postharvest mushroom freshness.


Assuntos
Agaricus/química , Bactérias/metabolismo , Fenômenos Químicos , Nanopartículas/química , Ácidos/análise , Dióxido de Carbono/análise , Catecol Oxidase/metabolismo , Quitosana/química , Cor , Eletrólitos/análise , Nisina/química , Oxigênio/análise , Solubilidade
12.
Foods ; 10(11)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34828922

RESUMO

The Rutab date involves a physiological process by which the fruit turns completely ripe. The objective of this study was to research the effect of ATP-treated fruit to improve their biologically active compounds of the Rutab process of the 'Zagloul' date during shelf-life. Fruits at full color (red) were dipped in 0, 1, 1.5 mmol L-1 ATP solution for 10 min, and then stored at room temperature (27 ± 1 °C) with a relative humidity of (67 ± 4 RH%) for 12 d. We found that ATP treatment, especially at 1.5 mM, enhances the Rutab stage of date fruit, and certain biologically active compounds such as total phenols and flavonoids, in all ATP treatments compared to untreated fruits. ATP enhanced the loss of tannin compounds in fruit but had no impact on the change in fruit moisture percentage of fruit during storage. The treatments did affect the changes in total sugar content and activated the sucrose enzymes, i.e., acid invertase (AI), neutral invertase (NI), sucrose synthase-cleavage (SS-c), and sucrose synthase-synthesis (SS-s) during storage. Interestingly, immersion in 1.5 mM ATP forced the date fruit to reach the Rutab stage during storage. These results indicated that the dose of ATP (1.5 mM) is a new potential tool that pushes the fruits to regular ripening after harvest, thus reducing the losses in the fruits during the production process. A linear model could be satisfactorily used for predicting the properties of the treated date with ATP 1.5 mM at different shelf-life durations.

13.
Foods ; 8(2)2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30736332

RESUMO

Developing a bioactive brew is a novel track for revalorization of palm date byproducts. The effect of roasting temperature (160, 180 and 200 °C ) and roasting time (10, 20 and 30 min) on the hardness of the roasted date seeds, moisture content of the defatted roasted date seed powder (DRDSP), bulk density of the DRDSP, color parameters of DRDSP, quality attributes (extraction yield, pH and browning index), the chemical properties (antioxidants and total phenolic content) and the sensory attributes (color, aroma, taste and overall preference) of the brew prepared from DRDSP was studied. The physicochemical, quality, and sensory attributes were found to be significantly influenced by the roasting temperature and time. Additionally, the models proposed could satisfactorily describe the changes in the different properties during the roasting process. The optimum conditions of the roasting process obtained using the superimposed contour plot were 199.9 °C and 21.5 min. In the longer term, the results of this study would be beneficial for the manufacturers of the date seeds powder and brew.

14.
Antioxidants (Basel) ; 8(7)2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31323854

RESUMO

Full-fat roasted date seeds are considered an excellent source of antioxidants which can treat many diseases. The specific objectives were to investigate the effect of roasting temperature and time on the hardness of whole seeds, moisture content of the roasted date seeds powder, DPPH radical scavenging activity, total phenolic contents, extraction yield, pH, browning index and sensory properties of the brew prepared from the full-fat roasted date seeds and to construct descriptive models that could describe this effect. Date seeds were roasted at three temperatures (160, 180 and 200 °C) for different period of times (10, 20 and 30 min) using a natural conventional oven; then grinded and next brewed. Hardness of whole seeds, moisture content of the seeds powder, DPPH radical scavenging activity and total phenolic contents, extraction yield, pH and browning index and sensory properties of the brew were significantly affected by the roasting conditions. The statistical results indicated that the proposed model could adequately describe the measured properties. Strong correlations have been found among the properties of the brew as well. The producers of the date seeds brew can utilize these results for controlling the roasting process.

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