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Article

Emese Jeney‐Nagymate and Peter Fodor

The purpose of this paper is to examine the stability and the parameters affecting the stability of vitamin C in beer, wine and orange juice.

Abstract

Purpose

The purpose of this paper is to examine the stability and the parameters affecting the stability of vitamin C in beer, wine and orange juice.

Design/methodology/approach

In this study, a high performance liquid chromatography method was applied for reliable determination of ascorbic acid in these beverages. Three different types of beer, a wine and orange juice sample were spiked with ascorbic acid using different concentrations and pH values. The samples were stored at 4oC, but in some cases 20oC was also used as storage temperature. The joint effect of vitamin C and E was also examined.

Findings

The results demonstrated that vitamin C was stable only in orange juice at the original pH values. Under pH=4, beer was also a good matrix for vitamin C addition, but only at low storage temperature (4oC). Vitamin E addition increased the stability of ascorbic acid (p<0.05) even at room temperature.

Practical implications

These findings could have significant implications to the beer industry. This study shows that vitamin C can be stable in beer during the shelf life of this product using appropriate pH and storage temperature.

Originality/value

The paper shows that the addition of an antioxidant vitamin is good from the point of view of the consumer's health, and it can improve the shelf life of the food because of its antioxidant activity.

Details

British Food Journal, vol. 110 no. 3
Type: Research Article
ISSN: 0007-070X

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Article

David A. Bender

Average intakes of vitamin B6 are equal to, or greater than, reference nutrient intakes and clinical deficiency disease due to inadequate dietary intake is unknown…

Abstract

Average intakes of vitamin B6 are equal to, or greater than, reference nutrient intakes and clinical deficiency disease due to inadequate dietary intake is unknown. Although there is little scientific evidence of efficacy, the vitamin is widely recommended for treatment of premenstrual syndrome at levels of 50‐100mg/day (compared with reference nutrient intakes of under 2mg/day). At higher levels of intake (over 1,000mg/day), there is clear evidence of nerve damage, and there have been reports of symptoms of nerve damage in people taking between 50‐100mg/day.

Details

Nutrition & Food Science, vol. 97 no. 4
Type: Research Article
ISSN: 0034-6659

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Article

Dilys Wells

Vitamin A Vitamin A is essential for healthy mucous membranes which line all the body's internal tracts, such as the digestive, urinary and respiratory systems. Vitamin A…

Abstract

Vitamin A Vitamin A is essential for healthy mucous membranes which line all the body's internal tracts, such as the digestive, urinary and respiratory systems. Vitamin A is required for vision in dim light and it is essential in order that the delicate linings of the eye lids and the coverings of the eye ball stay healthy. Vitamin A also appears to be needed for a healthy outer skin.

Details

Nutrition & Food Science, vol. 82 no. 2
Type: Research Article
ISSN: 0034-6659

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Article

Ivan M. Sharman

Professor H. M. Evans, when making a study of the reproductive capacity of rats at the University of California in 1922, found that animals given a diet containing all the…

Abstract

Professor H. M. Evans, when making a study of the reproductive capacity of rats at the University of California in 1922, found that animals given a diet containing all the then known vitamins failed to produce normal litters. This observation indicated that another vitamin was required for fertility and subsequently led to the recognition of vitamin E. The vitamin was known to be present in lettuce and wheat germ, since when either of these were added to the rats' feed their fertility was restored. Subsequently, in 1936, by a lengthy procedure for concentrating the vitamin, Evans was successful in isolating the pure substance from wheat germ oil. It was identified as an alcohol with the chemical formula G29H50O2 and found to be fat soluble. At the suggestion of Professor G. Calhoun, Evans introduced the name “a‐toco‐pherol” for the pure compound (from the Greek tokos = childbirth, phero = to bear, and “‐ol” indicating that the substance is an alcohol).

Details

Nutrition & Food Science, vol. 73 no. 4
Type: Research Article
ISSN: 0034-6659

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Article

Elsie M. Widdowson

Vitamin D is one of the fat‐soluble vitamins. Its function in the body is to promote the absorption of calcium from the intestine and deposition of calcium in developing…

Abstract

Vitamin D is one of the fat‐soluble vitamins. Its function in the body is to promote the absorption of calcium from the intestine and deposition of calcium in developing bone. If the young child does not have sufficient vitamin D he develops rickets. Vitamin D can be obtained in two ways, from the food, or by the action of the ultraviolet rays of the sunlight on a fatty substance, 7 dehydrocholesterol, in the deeper layers of the skin. There is at present no method for making a quantitative assessment of the amount of vitamin D obtained in this way, but it is believed to be the natural and most important means by which the body acquires its vitamin D. However, if a person does not expose his body to the sunlight, either because he (or more likely she) covers it up when she goes out, or stays indoors, or lives in northern parts of the world where there is no sunlight for many months of the year, there can be no conversion of 7 dehydrocholesterol to vitamin D. Even as far south as Scotland in the winter there is virtually no ultraviolet light. Vitamin D can be stored in the liver and body fat, so that a sunny summer may allow a store to be built up which can be drawn upon in the winter. However, whenever sunlight and particularly ultraviolet light does not reach exposed parts of the skin dietary sources of vitamin D become of major importance. The richest dietary sources of vitamin D are fatty fish such as herrings, kippers, pilchards and mackerel, but few people eat enough of these fish for them to be an important day to day provider of the vitamin. Most of our dietary vitamin D comes from margarine which is fortified with the vitamin, and eggs. Egg yolk contains about 5 micrograms of vitamin D per 100 grams, fortified margarine 8 micrograms and herrings, bloaters and kippers 25 micrograms per 100 grams.

Details

Nutrition & Food Science, vol. 79 no. 3
Type: Research Article
ISSN: 0034-6659

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Article

Chuli Zeng

Vegetables are rich in vitamin C, but most of them are commonly cooked before being consumed. The objective of the present study was to evaluate the effects of three…

Abstract

Purpose

Vegetables are rich in vitamin C, but most of them are commonly cooked before being consumed. The objective of the present study was to evaluate the effects of three common cooking methods (i.e. steaming, microwaving, and boiling) on the vitamin C content of broccoli, spinach, and lettuce.

Design/methodology/approach

100 g of homogeneous pieces of broccoli, spinach, and lettuce was separately processed for 5 minutes by steaming, microwaving, and boiling. A simple UV analytical method was employed to determine the vitamin C content of the vegetables.

Findings

Loss of vitamin C in broccoli, spinach, and lettuce during steaming was 14.3, 11.1, and 8.6 per cent, respectively, while the loss of vitamin C during boiling was 54.6, 50.5, and 40.4 per cent, respectively. During microwaving, loss of vitamin C in broccoli, spinach, and lettuce was 28.1, 25.5, and 21.2 per cent, respectively.

Practical implications

This study shows that any raw vegetable contains the highest content of vitamin C compared to that of cooked one. Eating raw vegetables is the best way to obtain vitamin C. Cooking methods (i.e. steaming, microwaving, and boiling) have huge impacts on the vitamin C content of vegetables. Steaming is the best cooking method for retaining the vitamin C content in vegetables.

Originality/value

This study evaluates for the first study the effects of three common cooking methods (i.e. steaming, microwaving, and boiling) on the vitamin C content of broccoli, spinach, and lettuce.

Details

Nutrition & Food Science, vol. 43 no. 5
Type: Research Article
ISSN: 0034-6659

Keywords

Abstract

Purpose

Adipose tissue accumulation by trapping vitamin D and reducing its level may cause serious side effects. The purpose of this study is to determine the effects of vitamin D supplementation on dehydroepiandrosterone (DHEA), paraoxonase 1 (PON 1), insulin, free fatty acid (FFA), apolipoprotein-AI (Apo-AI) and apolipoprotein B (Apo-B) concentration in obese and overweight participants under low-calorie diet (LCD) program.

Design/methodology/approach

Healthy overweight and obese individuals (n = 70) with vitamin D deficiency were randomly assigned into 2 groups to receive either vitamin D supplements (an oral 2,000 IU vitamin D supplement) or placebo for 8 weeks.

Findings

All the participants were given an LCD program during the intervention. Vitamin D supplementation led to a significant increase in the levels of 25(OH)D (vitamin D vs placebo groups: 36.6 ± 9.8 vs 19.9 ± 3.5 ng/mL, p < 0.001), PON 1 levels (vitamin D vs placebo groups: 80 ± 25 vs 58 ± 23.2 ng/mL, p = 0.001), DHEA concentration (vitamin D vs placebo groups: 2.3 ± 0.7 vs 1.5 ± 0.6 ng/mL, p < 0.001) and Apo-AI levels (vitamin D vs placebo groups 3.7 ± 0.5 vs 3 ± 0.5 mg/dL, p < 0.001). Besides, intake of vitamin D supplements led to a significant decrease in FFA (vitamin D vs placebo groups: 3.1 ± 0.75 vs 3.5 ± 0.5 ng/mL, p = 0.001). After adjusting the analyses based on baseline levels, age and baseline body mass index measures, significant changes were observed in the insulin levels (0.03 ± 0.06 vs −1.7 ± 0.6 µIU/ml, p = 0.04). But the authors did not find any significant difference in the concentration of Apo-B between groups (vitamin D vs placebo groups: 71.5 ± 35.5 vs 66.6 ± 28.5 mg/dL, p = 0.05).

Originality/value

Overall vitamin D supplementation for eight weeks among vitamin D-deficient obese and overweight participants had beneficial effects on serum DHEA PON 1 FFA insulin and Apo- AI while it did not affect the Apo-B concentration.

Details

Nutrition & Food Science , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0034-6659

Keywords

Abstract

Details

The Political Economy of Antitrust
Type: Book
ISBN: 978-0-44453-093-6

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Article

Amir-Hossein Avestaei, Mahdi Yaghchiyan, Alireza Ali-Hemmati, Mahdieh Abbasalizad Farhangi, Mehran Mesgari-Abbasi and Parviz Shahabi

Obesity is a major risk factor for chronic renal fibrosis and kidneys’ structural and inflammatory impairments. This study aims to examine the possible therapeutic effects…

Abstract

Purpose

Obesity is a major risk factor for chronic renal fibrosis and kidneys’ structural and inflammatory impairments. This study aims to examine the possible therapeutic effects of vitamin D supplementation against renal inflammatory and kidney’s structural fibrosis and degeneration.

Design/methodology/approach

Forty male Wistar rats were divided into two groups for 16 weeks: normal diet (ND) and high-fat diet (HFD); then, each group was subdivided into two groups including ND, ND + vitamin D and HFD, HFD + vitamin D. Vitamin D supplementation was done for five weeks at 500 IU/kg dosage. Renal tissue concentrations of tumor necrosis factor (TNF)-α, interleukin 6, interleukin 1 beta, monocyte chemoattractant protein (MCP)-1 and transforming growth factor-beta (TGF-β), serum values of lipids, markers of glucose homeostasis and urea, creatinine and uric acid and renal tissue histological and structural changes were determined.

Findings

HFD feeding caused remarkable histological and structural changes including higher TNF-α, MCP-1 and TGF-β concentrations in renal tissues of rats, whereas vitamin D has potent anti-inflammatory effects (P = 0.036, 0.047 and 0.02, respectively). Vitamin D administration also reduced urea and uric acid concentrations (P = 0.023 and 0.049, respectively). Moreover, vitamin D reduced glomerulomegaly, reduced lipid accumulation and limited dilated Bowman’s space in rats and improved glycemic status by increasing insulin (P = 0.04) and reducing insulin resistance (P = 0.006).

Research limitations/implications

The current study has some limitations. It was better to measure the level of inflammatory cytokines’ expression in the kidney tissues. Additionally, the measurement of baseline values of inflammatory cytokines was not possible because of the possibility of animals’ drop-out.

Practical implications

According to the study findings, vitamin D treatment in the current report showed a significant therapeutic role in reducing inflammation, improving glycemic and lipid abnormalities and structural and histological modifications in renal tissues of rats. These findings have a great value because after confirming in a human model, vitamin D can be suggested as a potential therapeutic tool in clinical practice.

Social implications

After being confirmed by other animal or human researches, the results of the current work could have great social implications by reducing the prevalence of obesity-related renal complications and highlighting the beneficial roles of vitamin D.

Originality/value

To the best of the authors’ knowledge, this is the first study to investigate the histological and inflammatory changes in the kidneys and metabolic parameters in the HFD induced rats and also clarified the therapeutic roles of vitamin D in ameliorating the inflammatory, histological, metabolic and functional changes in the kidneys of obese rats.

Details

Nutrition & Food Science, vol. 50 no. 6
Type: Research Article
ISSN: 0034-6659

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Article

Asal Neshatbini Tehrani, Hossein Farhadnejad, Amin Salehpour and Azita Hekmatdoost

This study aims to investigate the association of vitamin D intake and the risk of depression, anxiety and stress among Tehranian female adolescents.

Abstract

Purpose

This study aims to investigate the association of vitamin D intake and the risk of depression, anxiety and stress among Tehranian female adolescents.

Design/methodology/approach

This cross-sectional analysis included 263 participants. A valid and reliable food frequency questionnaire was used to determine dietary intake of vitamin D. Depression, anxiety and stress scores were characterized by Depression Anxiety Stress Score-21 questionnaire. Multivariable logistic regression was used to estimate the odds ratio (OR) for the occurrence of depression, anxiety and stress according to the tertiles of vitamin D intake.

Findings

The mean ± standard deviation age and body mass index (BMI) of participants were 16.2 ± 1.0 years and 22.2 ± 4.1 kg/m2, respectively. Mean score of depression, anxiety and stress of participants were 9.8 (low-grade depression), 8.4 (low-grade anxiety) and 14.0 (borderline for stress), respectively. In the final model, after adjustment for age, BMI, physical activity, mother/father’s education level, dietary fiber and total energy intake, the OR for depression in the highest compared to the lowest tertile of vitamin D intake was 0.53 (95% confidence interval [CI], 0.24–0.98) (p for trend: 0.040). Moreover, based on the fully adjusted model, participants in the highest tertile of vitamin D intake had lower odds of stress (OR: 0.49; 95% CI: 0.23–0.93), in comparison to those in the lowest one (p for trend: 0.021).

Originality/value

To the best of the authors’ knowledge, this is the first study to assess the association of vitamin D intake and risk of psychological disorders, including depression, stress and anxiety in Middle East and North Africa region’s female adolescents.

Details

Nutrition & Food Science , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0034-6659

Keywords

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