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1.
Heliyon ; 9(8): e19166, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37654449

RESUMO

In recent years the use of hybrid drying methods has been noticed because of the improvement of the dried products quality. The effect of infrared (IR) power (0, 400, 600, and 800 W) in combination with convective hot air (60 °C, 3 m/s) on the quality properties of black raspberry pulp during foam mat drying was investigated in this study. According to the findings, increasing the IR power, (IR-CHA) had no effect on the moisture content, moisture ratio, or drying rate of the product; however, the effective moisture diffusion coefficient (Deff) was significantly increased. The effect of IR power on the physicochemical properties of black raspberry powder revealed that combining infrared with convective hot air (IR-CHA) improved the powder's flowability and total polyphenol content while decreasing its moisture content (p < 0.05). Furthermore, FESEM images revealed that the increase in IR power resulted in particles with smooth surfaces.

2.
J Health Popul Nutr ; 42(1): 71, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491318

RESUMO

BACKGROUND: The benefits and harms of vitamin D supplementation in the treatment of COVID-19 have not yet been fully documented. In this study, we aimed to evaluate the effects of high-dose vitamin D supplementation on liver function tests in COVID-19. METHOD: This double-blinded randomized clinical trial was conducted on 140 hospitalized patients aged > 30 years. Patients were randomly allocated to receive either intervention group (n = 70 receiving 50,000 IU of vitamin D capsules orally as a single dose and then 10,000 IU syrup daily from the second day of admission for 30 days) and the control group (n = 70 receiving 1000 IU vitamin D syrup orally per day). Liver function tests (LFT), including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), and Lactate Dehydrogenase (LDH) were evaluated at baseline and at the end of the intervention. Decision tree analysis was performed to identify the predictors for change in liver enzymes. RESULTS: Among COVID-19 patients, a significant decrease was observed in serum level of ALP between intervention and placebo groups (p = 0.04). In addition, decision tree analysis revealed that GGT, temperature, serum magnesium level at baseline and gender were the most important predictors of ALT changes in COVID-19 patients. CONCLUSION: High-dose vitamin D supplementation improved ALP markers among COVID-19 patients. More randomized controlled trials with longer follow-up times will be required.


Assuntos
COVID-19 , Vitamina D , Humanos , Testes de Função Hepática , Fosfatase Alcalina , gama-Glutamiltransferase , Método Duplo-Cego , Suplementos Nutricionais , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Food Sci Nutr ; 10(4): 1103-1112, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35432953

RESUMO

In spite of grapeseed oil high contents of linoleic acid, its oxidative stability is relatively low, and mixing with more stable oils such as sesame oil can be a good way to improve the oxidative stability of this oil. The aim of this study was to increase the oil oxidative stability by producing an optimum formulation due to the combination of grapeseed and sesame oil. For this purpose, some of the qualitative properties of the optimum formulation were investigated during frying process. For finding the best formulation, the quantities of 0%, 25%, 50%, 75%, and 100% of sesame oil were blended with 100, 75%, 50%, 25%, and 0% of grapeseed oil. The results show that the highest percentage of fatty acid in various samples (sesame oil, grapeseed oil, and mixed formulations) is related to the linoleic acid, followed by oleic, palmitic, and stearic acid. In conclusion the addition of sesame oil to grapeseed oil increased the number of phenolic compounds, antioxidant strength, and oxidative stability of the mixed oil samples. Considering the price of the product and the importance of the nutritional quality and stability of the oil, combining 75% sesame oil and 25% grapeseed oil has the best nutritional quality and lower cost than pure sesame oil formula. After frying process, comparison of sesame and grapeseed oil different factors with national Iranian standard limits showed that the parameters of acid number and peroxide value were more than Iran's national standard, but the content of polar compounds was within the permissible content. Finally, the mixture of sesame and grapeseed oil is not suitable for long-term heating and frying.

4.
Int J Biol Macromol ; 165(Pt A): 776-786, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33010269

RESUMO

In the current study, sunflower by-product pectin (SFBP) was obtained using ultrasound-assisted extraction (UAE) technique. The UAE variables were successfully optimized, and the optimal condition (irradiation time 30 min, temperature 33 °C and ultrasound power 400 W) yielded 11.15%. Under this condition, SFBP was rich in low-esterified galacturonic acid content (72.94%), and had long side branches of galactan, arabinogalactan, and arabinan, with an average molecular weight of 175.353 kDa. The structural properties were characterized using FTIR, NMR, XRD spectroscopies. The thermal analysis by DSC and TGA suggested suitable thermal stability for SFBP. The solubility, water and oil holding capacities, emulsifying capacity, emulsifying stability (vs various conditions), foam capacity, foam stability, DPPH and ABTS inhibitions, and reducing power assay were measured to evaluate the potential of SFBP to be considered as a food ingredient.


Assuntos
Helianthus/química , Pectinas , Ondas Ultrassônicas , Pectinas/química , Pectinas/isolamento & purificação
5.
Int J Biol Macromol ; 137: 253-260, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260777

RESUMO

Pectic compounds are responsible for turbidity in many juices. The elimination of these compounds, such as using pectinase can improve the appearance and storage stability of the products. In this study, the covalent immobilization of pectinase from Aspergillus aculeatus was studied on alginate-montmorillonite beads. The prepared beads were characterized by FT-IR and SEM. The immobilization procedure did not affect the optimal temperature (40 °C) of pectinase for achieving the maximum activity but the optimal pH changed was reduced from 5.5 to 5.0. A significant decrease in Michaelis constant (Km) value was observed after immobilization, indicating the affinity of enzyme to the substrate has been enhanced after immobilization, although the thermal stabilities of both forms of enzymes were comparable. After 6 cycles reusing of immobilized enzyme, its initial activity was remained about 53%. Finally, the immobilized pectinase was applied for the clarification of pineapple juice, showing that the immobilized enzyme is promising for use in the fruit juice industry.


Assuntos
Alginatos/química , Bentonita/química , Enzimas Imobilizadas , Microesferas , Poligalacturonase/química , Reagentes de Ligações Cruzadas , Ativação Enzimática , Estabilidade Enzimática , Sucos de Frutas e Vegetais/análise , Concentração de Íons de Hidrogênio , Cinética , Análise Espectral , Termodinâmica , Viscosidade
6.
Colloids Surf B Biointerfaces ; 178: 421-429, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30908998

RESUMO

In this research, bioactive peptides produced from flaxseed protein by alcalase, pancreatin, trypsin and pepsin, were encapsulated by spray drying. After analysis of amino acid composition and antioxidant properties of hydrolysates, the effect of spray-drying encapsulation via different maltodextrin (MD) to hydrolysate ratios (1:1, 2:1 and 3:1 w/w) on the production yield, physicochemical properties, functional activities, chemical structure, and morphology of final powder particles were evaluated. Among the hydrolysates, peptides produced with alcalase had the highest hydrolysis degree (38.2%), hydrophobic amino acids (255 mg/g) and antioxidants (126 mg/g). Among spray-dried samples, the powders obtained by 3:1 w/w ratio (MD: peptide) showed the highest radical scavenging activity for DPPH- (68.93%), ABTS+ (85.62%), hydroxyl (94.97%), nitric oxide (64.03%), reducing power (95.49%), total antioxidant activity (96.68%), and iron (95.31%) and copper (95.49%) chelating activity. Evaluation of chemical structure (FTIR) indicated that hydrolysates were coated and dispersed within maltodextrin matrix. SEM images showed the effect of different carrier ratios on the production of irregular and shrunk particles with different sizes and matrix-type structures.


Assuntos
Linho/enzimologia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Antioxidantes/química , Compostos de Bifenilo/química , Óxido Nítrico/química , Picratos/química
7.
Ultrasonics ; 96: 104-122, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30827686

RESUMO

The objective of this study was to intensify combined intermittent microwave - low temperature (40 °C) hot air drying with ultrasound. The process variables were ultrasound time (40 kHz for 0, 10, 20 and 30 min), microwave power (360, 600 and 900 W), and microwave pulse ratio (1, 2, 3 and 4). Results showed that the highest reduction in moisture content was observed in the samples pretreated with ultrasound for 10 min and then dried at 900 W microwave with the pulse ratio of 4. As ultrasound time, microwave power and pulse ratio increased, significant increases were noticed in Deff by 4.89, 16.44 and 20.7%, respectively. Moreover, shrinkage was lower in the samples pretreated with lower ultrasound time and microwave pulse ratio. Besides, bulk density reduced when the microwave power was increased due to lower volume reduction. In addition, the highest increase in rehydration (32.23%) was observed in the samples dried using the high-power intermittent microwave. Finally, the highest significant reduction in specific energy consumption as a result of increased microwave power was 23.32%. In general, results of this study demonstrated that the ultrasound-intensified combined intermittent microwave - low temperature hot air drying may be a suitable alternative for industrial applications.


Assuntos
Dessecação/métodos , Micro-Ondas , Solanum tuberosum , Manipulação de Alimentos/métodos , Temperatura Alta , Ultrassom
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