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1.
Heliyon ; 10(14): e34672, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39130449

RESUMO

The influence of pre-treatments and different dehydrating temperatures on the drying dynamics, energy consumption, and quality attribute of yam chips was studied. Dehydration was executed employing a convectional oven dryer under four temperatures (50, 60, 70, and 80 °C) and 2.0 m/s air velocity. Yam chips were subjected to pre-treatment conditions of blanching (for 1, 2, 3, 4, and 5 min), citric acid (1 and 5 %), and ascorbic acid (1 and 5 %) solutions whereas, untreated yam chips samples served as the control. Dehydrated yam chips were further assessed for textural and colour properties. The drying rate was found to be faster at a higher temperature of 80 °C compared to lower temperatures of 50, 60, and 70 °C. The asymptotic model was established to be the suitable descriptive model for predicting moisture profile in the pre-treated yam chips based on highest R2 values (0.995-0.999), lowest χ2 values (4.422-18.498), and the root mean square error (RMSE) values (2.103-4.30). Pre-treatment and drying temperature had a significant (p < 0.05) impact on the hardness and colour of dehydrated yam chips. Blanching at 4 min yielded yam chips with most preferred texture (hardness: 81.3 N) and lightness (L*) in colour values (71.07 %) after drying compared to other pre-treated samples. The effective moisture diffusivity values of the pre-treated samples were in the range of 5.17294 × 10-9m2/s to 1.10143 × 10-8m2/s for 5 % citric acid samples at 50 °C and all pre-treated samples at 80 °C respectively. The general findings of the study indicated a least energy usage of 43.68 kWh as a cost-effective method of drying. Also, 4 min blanching, 5 % citric acid, and 1 % ascorbic acid at 80 °C were found to be the optimum conditions for pre-treating yam chips based on lower energy level consumption rates and improved sensory properties thus attributing to the quality of the dried yam chips.

2.
Food Sci Nutr ; 11(12): 7605-7617, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38107117

RESUMO

Diabetes mellitus is one of the chronic metabolic diseases whose control remains a challenge. Its increased incidence was mainly attributed to increased environmental contamination. Therefore, this study aims to investigate the effect of feeding clover microgreen (CM) on a diabetes model with or without aflatoxin exposure. Rats were distributed into 8 groups. G1 was a control group. G2 was fed CM. G3 was administered aflatoxin orally. G4 was fed clover and administered aflatoxin. G5 was diabetic rats. G6 was diabetic rats fed CM. G7 was diabetic rats administered aflatoxin. G8 was diabetic rats administered aflatoxin and fed CM. Phytochemical analysis of the CM showed that gardenin was the most common compound. The administration of aflatoxin aggravated diabetes. The groups fed CM showed a decreased glucose concentration compared to the unfed groups. Liver and kidney function parameters were improved by CM. The histopathological alteration of the pancreas, liver, and kidneys was relieved in CM-fed groups. The area % of insulin in islets of Langerhans was increased in CM-fed groups. Feeding CM also enhanced the oxidative stress biomarkers. In conclusion, CM improved all evaluated parameters in diabetic rats either exposed to aflatoxin or not compared to the control.

3.
Ultrason Sonochem ; 98: 106468, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37327688

RESUMO

Black rice is a functional food due to its higher protein, fiber, iron, antioxidant compounds, and other health benefits than traditional rice. The ultrasonic (US) pretreatments (10, 20, and 50 min) followed by hot-air drying (50, 60, and 70 °C) were applied to study the drying kinetics, mathematical modeling, thermodynamics, microstructure, bioactive profile, volatile compounds and to lock the nutritional composition of selenium-enriched germinated black rice (SeGBR). Ultrasonic-treated samples exhibited a 20.5% reduced drying time than control ones. The Hii model accurately describes the drying kinetics of SeGBR with the highest R2 (>0.997 to 1.00) among the fifteen studied models. The activation energy values in US-SeGBR varied from 3.97 to 13.90 kJ/mol, while the specific energy consumption ranged from 6.45 to 12.32 kWh/kg, which was lower than untreated. The obtained thermodynamic attributes of dried black rice revealed that the process was endothermic and non-spontaneous. Gallic acid, kaempferol, and cyanidin 3-glucoside were present in high concentrations in phenolics, flavonoids, and anthocyanins, respectively. The HS-SPME-GC-MS investigation detected and quantified 55 volatile compounds. The US-treated SeGBR had more volatile compounds, which may stimulate the release of more flavorful substances. The scanning electronic micrograph shows that the US-treated samples absorbed high water through several micro-cavities. Selenium concentration was significantly higher in US-treated samples at 50 °C than in control samples. In conclusion, ultrasound-assisted hot-air drying accelerated drying and improved SeGBR quality, which is crucial for the food industry and global promotion of this healthiest rice variety.


Assuntos
Oryza , Selênio , Antocianinas , Oryza/química , Cinética , Antioxidantes , Dessecação
4.
Foods ; 12(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36981162

RESUMO

Over the years, extrusion has been a multi-step thermal technique that has proven to be the most effective process to stabilize rice bran (RB). This study aimed to investigate the effects of extrusion treatment and temperature (15, 25, and 40 °C) on the storage stability, lipid oxidation, peroxidase, and peroxide values, free fatty acids, fatty acid composition, and protein variations of RB over 60 days. The study offers novel insights into the changes in RB's protein and amino acid compositions during extrusion and storage, which has not been extensively explored in prior research. After extrusion processing, peroxidase activity (POD) and lipase activity (LPS) were significantly reduced. However, peroxide value (PV), free fatty acids (FFA), and malondialdehyde content (MDA) observed a significantly increased by 0.64 mEqO2/kg, 8.3 mg/100 g, and 0.0005 µmol/L respectively. The storage stability of RB after extrusion shows that the POD, LPS, FFA, PV, and MDA were positively correlated with storage duration and temperature. The oleic acid/linoleic acid ratio in processed RB by extrusion had no significant changes during storage. The total and essential/non-essential amino acid ratios showed a downward trend of 5.26% and 8.76%, respectively. The first-order kinetics was the best-fitting model to describe the enzymatic inactivation and degradation of extruded RB during storage. The extrusion treatment did not affect the crude protein and the essential subunits of protein. Overall, the optimized extrusion procedure exhibited promising results in stabilizing the RB.

5.
Foods ; 11(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36141006

RESUMO

In an era of rapid technological development, ultrasound technology is being used in a wide range of industries. The use of ultrasound technology in fruit and vegetable processing to improve production efficiency and product quality has been an important research topic. The cleaning of whole fresh fruits and vegetables is an important part of fruit and vegetable processing. This paper discusses the development process of components of the ultrasonic equipment, the application of ultrasonic technology in fruit and vegetable cleaning, and the research advances in ultrasonic cleaning technology. Moreover, the feasibility of ultrasonication of fruits and vegetables for cleaning from the perspectives of microbial inactivation, commodity storage, and sensory analysis were discussed. Finally, the paper identified the inevitable disadvantages of cavitation noise, erosion, and tissue damage in fruit and vegetable processing and points out the future directions of ultrasonic fruit and vegetable cleaning technology.

6.
Molecules ; 27(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35745026

RESUMO

In this study, the volatile compound profiles of gurum seed oil were determined using two methods: supercritical CO2 extraction (SFE) and the screw press process (SPP). For volatile compounds extraction and identification, headspace solid-phase micro-extraction (HS-SPME) and GC-MS were used, respectively. A total number of 56 volatile compounds were revealed and identified in oil extracted by SFE, while only 40 compounds were detected in extracted oil by SPP. Acids, aldehydes, esters, ketones, furans, and other components were present in the highest ratio in oil extracted by SFE. In contrast, alcohols and alkenes were found in the highest proportion in oil extracted by SPP. In this study, it was observed that SFE showed an increase in the amounts of volatile compounds and favorably impacted the aroma of gurum seed oil. The results reveal that different extraction methods significantly impact the volatile components of gurum seed oil, and this study can help evaluate the quality of the oil extracted from gurum seeds.


Assuntos
Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos de Plantas , Sementes/química , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise
7.
Food Chem ; 373(Pt B): 131436, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34740052

RESUMO

Milk and dairy products are considered as essential sources of lipid-soluble vitamins (LSVs) for human nutrition. Due to the lower concentrations, complexity, and instability of LSVs during extraction, their quantification remains challenging. This review focus on advances in the extraction and quantification of LSVs from different dairy products. Saponification, and liquid-liquid (LLE), solid-phase (SPE), and supercritical fluid (SFE) extraction methods, as well as dispersive liquid-liquid microextraction, are the most common techniques. Liquid chromatography-mass spectrophotometry (LC-MS) has unique advantages for LSVs determination and quantification due to its high sensitivity and specificity.


Assuntos
Extração em Fase Sólida , Vitaminas , Animais , Cromatografia Líquida , Humanos , Lipídeos , Leite/química , Vitaminas/análise
8.
Ultrason Sonochem ; 68: 105226, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32599166

RESUMO

The influence of ultrasonic frequency (20 kHz) and glucose pretreatments either alone or in combination on the drying of sweet potato slices (3 mm) using a hot-air dryer at 60 °C was tested to study the kinetics modeling, phytochemicals, antioxidant activities, and functional and textural changes of the final dried product. The results indicated that total phenolic content and total flavonoid content were significantly higher in glucose-pretreated samples while antioxidant activities were higher in ultrasound- and glucose-pretreated samples. For vitamin C, much degradation occurred in the glucose-pretreated samples when compared with the other pretreated samples apart from the control. Enzymatic browning made a minor contribution to the ultrasound/glucose-pretreated samples, while no significant differences were noted in the glucose-pretreated samples. A modified Henderson and Pabis (MHP) model, followed by the two-term and Hii models, fitted best among the 15 selected mathematical models. Fourier Transform Infrared Spectroscopy (FTIR) analysis revealed the presence of glucose, phenols, and flavonols in all samples. Microstructural analysis confirmed the hardness (N) in the final glucose-pretreated samples due to glucose layers and less cell damage.


Assuntos
Glucose/química , Ipomoea batatas/química , Modelos Teóricos , Compostos Fitoquímicos/análise , Ondas Ultrassônicas , Dessecação
10.
Food Funct ; 11(1): 1146-1154, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31830159

RESUMO

In this study, separation of peptides with Angiotensin I converting enzyme (ACE)-inhibitory capacity obtained from ultrasonically pretreated defatted corn germ protein (DCGP) by using a new continuous system of enzymatic hydrolysis coupled with membrane separation (EHC-MS) was investigated. Ultrasonic pretreatment was applied to enhance the enzymatic hydrolysis rate of DCGP, as proved in our previous study. The EHC-MS system was operated in two modes which included the batch system and continuous system with continuous water and substrate feeding and was compared with the EH-offline-MS system. The selection of the membrane was based on the hydrolysate fraction which had the highest activity for inhibition of ACE. The results showed that the 1-3 kDa fraction of DCGP hydrolysates had the lowest IC50 value (0.124 mg mL-1) for inhibition of ACE. The degree of conversion (%) of DCGP and output of peptides per unit of the enzyme were significantly (P < 0.05) increased by 55.3% and 55% in the EHC-MS batch process and 79% and 473% in the EHC-MS continuous operation compared to the EH-offline-MS system. The EHC-MS using continuous water and substrate feeding operation was noted to be the best in terms of a high degree of DCG protein conversion (75.68 ± 1.34) and the output of peptides per unit of the enzyme (78.65 ± 1.13). The results revealed that the EHC-MS method with constant water and substrate feeding could show a better application in peptide production in the food industry.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Peptídeos/isolamento & purificação , Proteínas de Plantas/isolamento & purificação , Hidrolisados de Proteína/química , Zea mays/química , Fracionamento Químico , Hidrólise , Membranas , Ondas Ultrassônicas
11.
J Food Sci Technol ; 56(11): 4867-4878, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31741511

RESUMO

The detrimental health implications of chemical preservatives in fruits have necessitated exploitation of safe and natural alternatives such as edible gums. This work studied shelf-life extension in grape (Pinot noir) under cold storage by xanthan gum (XAN) coatings enriched with ascorbic acid (XANAS) and citric acid (XANCI). Standard scientific methods were used to examine some sensory (color, texture-resilience and hardness), enzyme, anthocyanine and antioxidant activities. Also, the reaction rate mechanism was examined through modeling of selected shelf-life indicators; color change, weight loss, and antioxidants. The results revealed that, Xanthan gum and its acid modified coatings significantly (p < 0.05) suppressed polyphenol oxidase, ascorbic acid oxidase, polymethyl etherase acitivies and maintained the structural integrity of the grape during the 21 days storage period. Weight loss (%) in the grape samples was 13.66 < 13.98 < 14.16 < 15.64 in the order XANAS < XANCI < XAN < CONTROL whilst ferric reducing antioxidant power (FRAP) activity was 150.23 > 143.18 > 136.49 > 104.5 mg/100 g AEAC corresponding to XAN > XANAS > XANCI > CONTROL. Significantly (p < 0.05) higher phytochemical contents were observed in the gum coatings compared to the control. Through statistical parameters such as the coefficient of determination (R 2), root mean square error (RMSE) and reduced Chi square (χ2), the second-order polynomial model predicted precisely the decomposition of color, weight loss and FRAP of grape. Color deterioration was attributed to changes in b* parameter as a result of phenolics and phytochemical decompositions resulting from enzymatic activities. Conclusively, acid modified xanthan gum coatings could preserve phytochemicals, color, antioxidant and textural properties of grape in cold temperature storage.

12.
Food Funct ; 10(9): 6020-6029, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31482904

RESUMO

In this work, a defatted corn germ protein (DCGP) was pretreated with single frequency ultrasound at 20 kHz (SFU) and multi-frequency ultrasounds (20, 28, 35 and 40 kHz) (MFU). The microstructures, morphology, amino acid content, degree of hydrolysis, protein hydrolysate concentration and angiotensin-converting enzyme (ACE) inhibitory activity of the DCGP hydrolysate were analyzed. The results showed that both SFU and MFU pretreatments increased the ACE inhibitory activity of the DCGP hydrolysate more than that observed for the traditional method. Also, the SFU pretreatment showed the highest ACE inhibitory activity of 54% in comparison with that of the DCGP hydrolysates obtained via the traditional and MFU pretreatment methods. The results of ultraviolet-visible (UV-Vis) spectroscopy, fluorescence spectroscopy, surface hydrophobicity studies, Fourier-transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) and scanning electron microscopy (SEM) confirmed the extent of the changes that occurred in the microstructures and morphology of DCGP pretreated with SFU and MFU. The results also indicated that the hydrophobic amino acid concentration was comparably higher in DCGP pretreated with SFU and MFU than that in the DCG protein isolated via the traditional method.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Proteínas de Plantas/química , Zea mays/química , Hidrólise , Hidrolisados de Proteína/química , Ultrassom , Zea mays/efeitos da radiação
13.
J Food Biochem ; 43(8): e12948, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31368548

RESUMO

To improve the utility of walnut meal protein, influences of ultrasonication on the kinetic and thermodynamic constraints of enzyme (trypsin) hydrolysis were assessed using a multi-frequency counter current S-type ultrasound machine. Results revealed that both the ultrasonication treatment and control hydrolysis obeyed the first-order kinetics within the study constraints. After 90 min hydrolysis time, the uppermost percentage conversion rate (57.5%) of substrate to product and the percentage increase (25.42%) in hydrolyzed protein concentration were obtained at 323 K and 10% substrate concentration, respectively. The Michaelis constant (KM ) in ultrasonic enzymolysis declined by 58.66% over the control. The reaction rate coefficient (k) for the proteolysis improved by 84.75%, 52.43%, 48.25%, and 37.79% at 219, 303, 313, and 323 K, correspondingly. Generally, the bond energy (Ea ), enthalpy change (ΔH), entropy change (ΔS), and Gibbs free energy (ΔG) were reduced by the ultrasound pretreatment with 36.61%, 28.05%, 18.22%, and 5.24%, respectively. PRACTICAL APPLICATIONS: Walnut meal protein has a well-balanced amino acid profile and its economic utilization could be increased practicably as a food ingredient via production of hydrolysates/peptides for the production of improved food ingredients instead of being cast off as animal feed. This study demonstrated a positive bearing of ultrasonication-assisted alkaline pretreatment on proteolytic reaction characteristics and its energy efficiency for walnut meal protein, which makes this technique applicable to the enhancement of plant proteins for inclusion in food products, especially tree nut and oil seed waste products from the oil industry.


Assuntos
Manipulação de Alimentos/métodos , Juglans/química , Proteínas de Plantas/química , Tripsina/química , Álcalis/química , Aminoácidos/química , Biocatálise , Entropia , Manipulação de Alimentos/instrumentação , Cinética , Nozes/química , Proteólise , Termodinâmica , Ultrassom
14.
Food Sci Biotechnol ; 28(1): 75-85, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30815297

RESUMO

Drying and ß-carotenes retention kinetics were predicted using models in relative humidity (RH) drying condition. This was achieved by drying carrot slices using RH-convective hot-air dryer at 60, 70 and 80 °C under RH (10% 20% and 30%) conditions at 2.0 m/s air velocity. Three mathematical models describing thin layer were compared to their goodness of fit in terms of coefficient of correlation (R2), root mean square error (RMSE) and reduced Chi square ( χ 2 ). The Wang and Singh model could satisfactorily describe RH-convective drying of carrot slices with R2, RMSE and χ 2 in the ranges of 0.996-0.999, 5.4 × 10-4-9.4 × 10-4 and 0.0150-0.03353 respectively. The results reveal that a range of 3.61-8.2% retention of ß-carotene was observed for every 10% increase in RH in various drying air temperature. In summary, higher temperatures were mainly responsible for ß-carotenes degradation however this can be mitigated when drying is conducted under higher RH.

15.
Vaccine ; 37(6): 848-856, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30642731

RESUMO

BACKGROUND: Parents' attitudes and beliefs in vaccination are important to understand for shaping vaccine acceptance and demand interventions. Little research has focused on developing a validated scale to measure parents' attitudes towards vaccinations in low and middle-income countries; Ghana provided an opportunity develop a caregiver vaccination attitudes scale (CVAS) validated against childhood vaccine compliance. METHODS: We conducted a cluster survey of 373 households with children aged 12-35 months of age from Northern Region, Ghana. Caregivers responded to 22 vaccination behavior and belief survey items and provided the child's vaccination status. In exploratory factor analysis (EFA) to assess CVAS content validity, we used parallel analysis to guide the number of factors to extract and principal axis factor analysis for factor extraction. Reliability of the scale was assessed using McDonald's Omega coefficient. Criterion validity of scale and subscales was assessed against receipt of vaccinations by 12 months of age and vaccination delay, using number of days undervaccinated. RESULTS: EFA of CVAS responses resulted in removing 11 of 22 survey items due to loadings <0.30 and development of a 5-factor structure with subscales for Vaccine-Preventable Disease (VPD) Awareness, Vaccine Benefits, Past Behavior, Vaccine Efficacy and Safety, and Trust. The 5 factors accounted for 69% of the common variance and omega coefficients were >0.73 for all subscales. Validity analysis indicated that for every unit increase in the parent's scale score, the odds of the child being vaccinated decreased by 0.58 (95% confidence interval [CI]: 0.37, 0.68) and the number of days under-vaccinated increased by 86 (95%CI: 28, 143). The final 3-factor scale included Vaccine Benefits, Past Behavior, and Vaccine Efficacy and Safety. DISCUSSION: The final CVAS included three factors associated with vaccine compliance in Ghana, although several survey items suggested for use in vaccine acceptance scales were dropped. Replicating this study in several country settings will provide additional evidence to assist in refining a tool for use in routine vaccine acceptance and demand surveillance efforts.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pais/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Vacinação/psicologia , Adulto , Criança , Pré-Escolar , Comportamento Cooperativo , Análise Fatorial , Feminino , Gana , Humanos , Lactente , Masculino , Pais/educação , Reprodutibilidade dos Testes , Inquéritos e Questionários , Recusa de Vacinação/psicologia , Vacinas/administração & dosagem
16.
Food Chem ; 266: 309-316, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30381190

RESUMO

This study investigates the effects of catalytic infrared (CIR) dry-blanching (CIRDB) on the processing and quality of garlic slices. CIRDB processing parameters of CIR processing temperature, slice thickness and processing time were studied versus the processing characteristics of internal temperature, peroxidase (POD) activity and moisture reduction. Blanched garlic quality characteristics of surface color change (ΔE), allicin retention rate, vitamin C retention rate and microbial content were determined. Hot water blanching (WB) was used as a comparison. The results indicated that increasing CIR processing temperature and/or reducing the slice thickness accelerated internal temperature rise and POD inactivation and moisture reduction. To achieve 90% inactivation of POD, the CIRDB treatment resulted in moisture reductions of 15.87-40.37%, microbial reductions of 1.76-3.91-log, ΔE between 2.03 and 10.01, retention rate of allicin between 10.63 and 33.31%, and retention rate of vitamin C between 55.00 and 81.13%. CIRDB achieved the high-quality garlic products compared with WB.


Assuntos
Alho/química , Raios Infravermelhos , Ácido Ascórbico/química , Bactérias/efeitos da radiação , Cor , Culinária , Dissulfetos , Alho/metabolismo , Peroxidase/metabolismo , Ácidos Sulfínicos/química , Temperatura , Água/química
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