Search results

1 – 10 of over 4000
Article
Publication date: 21 March 2008

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.

1802

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

Keywords

Article
Publication date: 1 August 1997

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…

547

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

Keywords

Article
Publication date: 1 February 1982

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

Article
Publication date: 1 April 1973

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

Article
Publication date: 1 March 1979

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

Article
Publication date: 6 September 2013

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…

2741

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

Article
Publication date: 14 June 2022

Soraiya Ebrahimpour-Koujan, Amir Ali Sohrabpour, Saeid Safari, Nima Baziar, Shima Hadavi, Laleh Payahoo and Samaneh Shabani

Coronavirus disease-2019 (COVID-19) is becoming a crucial health problem worldwide. Continued and high-speed mutations of this virus result in the appearance of new…

Abstract

Purpose

Coronavirus disease-2019 (COVID-19) is becoming a crucial health problem worldwide. Continued and high-speed mutations of this virus result in the appearance of new manifestations, making the control of this disease difficult. It has been shown that well-nourished patients have strong immune systems who mostly have short-term hospitalization compared to others. The purpose of this study is to review the major nutrients involved in the immune system reinforcement and to explain nutritional aspects during the recovery of COVID-19.

Design/methodology/approach

In this review paper, the mechanistic role of nutrients in boosting the immune system and the nutritional aspects during the recovery of COVID-19 patients were discussed. Papers indexed in scientific databases were searched using antioxidants, COVID-19, inflammation, immune system, macronutrient, micronutrient and probiotic as keywords from 2000 to 2022.

Findings

Because of the adverse effects of drugs like thrombosis, pulmonary embolism and hypercholesterolemia, a balanced diet with enough concentrations of energy and macronutrients could increase the patient's durability. The inflammatory cytokines in a vicious cycle delay patients’ rehabilitation. The main mechanistic roles of micronutrients are attributed to the downregulation of virus replication and are involved in energy homeostasis. Dysbiosis is defined as another disturbance among COVID-19 patients, and supplementation with beneficial strains of probiotics helps to exert anti-inflammatory effects in this regard. Being on a well-planned diet with anti-inflammatory properties could reverse cytokine storms as the major feature of COVID-19. Future studies are needed to determine the safe and effective dose of dietary factors to control the COVID-19 patients.

Originality/value

Being on a well-planned diet with anti-inflammatory properties could reverse cytokine storms as the major feature of COVID-19. Future studies are needed to determine the safe and effective dose of dietary factors to control the COVID-19 patients.

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

Article
Publication date: 28 February 2022

Vijay Ganji, Tahra ElObeid, Zumin Shi, Hiba Bawadi, Abdelhamid Kerkadi, Noor Moussa, Hoda Ali and Alshaimaa Sobeih

Prevalence of vitamin D insufficiency among young Qatari women is ∼85%. The purpose of the study was to develop a food frequency questionnaire (FFQ) and to assess the…

Abstract

Purpose

Prevalence of vitamin D insufficiency among young Qatari women is ∼85%. The purpose of the study was to develop a food frequency questionnaire (FFQ) and to assess the degree of agreement between food vitamin D intakes derived from FFQ and 24-h food recall (24HFR) in young Qatari women.

Design/methodology/approach

A vitamin D-centric, 40-item FFQ was developed based on foods consumed in Qatar. In total, 36 Qatari women provided food intakes using FFQ and 24HFR. Vitamin D contents of foods reported in FFQ and 24HFR were computed. Spearman rank correlation was used to evaluate the relation between vitamin D intakes of FFQ and 24HFR. Bland–Altman (BA) plot and quartile comparisons were performed to determine the degree of agreement between food intakes of FFQ and 24HFR.

Findings

Median intakes of vitamin D from FFQ were significantly higher compared to the vitamin D content from 24HFR (213 IU vs 126 IU; p < 0.008). Vitamin D intakes were lower with 24HFR when compared with the intakes of FFQ. There was no significant relationship between food vitamin D intake from FFQ and 24HFR (Spearman rho = 0.16; p < 0.35). In cross classification, ∼64% were assigned to the same or adjacent quartiles. As per BA plot, more than 95% food intakes were within the limits of agreement (LOA) (BA index, 2.8%).

Originality/value

There was a moderate agreement between vitamin D intakes and FFQ and 24HFR. 24HFR should be used with caution in assessing the habitual food vitamin D intake because of limited sources of the vitamer in Qatari cuisine. The FFQ is suitable for estimating the food vitamin D intake in young Qatari women.

Details

British Food Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 23 March 2022

Muneeb Ahmad Malik, Yasmeena Jan, Afrozul Haq, Jasmeet Kaur and Bibhu Prasad Panda

The purpose of this study was to optimize the parameters for enhancing the vitamin D2 formation in three edible mushroom varieties, namely, shiitake mushroom (Lentinula

Abstract

Purpose

The purpose of this study was to optimize the parameters for enhancing the vitamin D2 formation in three edible mushroom varieties, namely, shiitake mushroom (Lentinula edodes), white button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus) using ultraviolet (UV) irradiation.

Design/methodology/approach

Freshly harvested mushrooms were irradiated with UV-B and UV-C lamps. Further, mushrooms were treated with UV-B at a distance ranging between 10 and 50 cm from the UV light source, for 15–150 min, to maximize the conversion of ergosterol to vitamin D2. Analysis of vitamin D2 content in mushrooms before and after UV exposure was done by high pressure liquid chromatography (HPLC).

Findings

HPLC results showed a significant (p < 0.001) increase in vitamin D2 levels of shiitake (17.3 ± 0.35 µg/g), button (24.9 ± 0.71 µg/g) and oyster (19.1 ± 0.35 µg/g) mushrooms, irradiated with UV-B at a distance of 20–30 cm for 120 min. Further, stability studies revealed that vitamin D2 levels in UV-B-irradiated mushrooms gradually increased for 48 and 72 h of storage at room and refrigeration temperatures, respectively. During cooking operations, 62%–93% of vitamin D2 was retained in UV-B-irradiated mushrooms.

Originality/value

This study describes the most effective parameters such as ideal wavelength, mushrooms size, duration of exposure and distance from UV sources for maximum vitamin D2 formation in edible mushrooms using UV irradiation. Further, assessment of vitamin D2 stability in UV exposed mushrooms during storage period and cooking operations has been carried out. In addition, this study also provides a comparison of the vitamin D2 levels of the three widely cultivated and consumed mushroom varieties treated simultaneously under similar UV exposure conditions.

Details

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

Keywords

1 – 10 of over 4000