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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.

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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: 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…

2803

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: 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: 6 June 2016

F.A. Faiz, J.S.K. Ngo and K.B. Bujang

This study aims to improve the natural dyeing recipe with better light fastness using ascorbic acid (vitamin C) with pulverised plant dyes.

Abstract

Purpose

This study aims to improve the natural dyeing recipe with better light fastness using ascorbic acid (vitamin C) with pulverised plant dyes.

Design/methodology/approach

Silk fabrics pre-mordanted with alum (aluminium ammonium sulphate) were dyed using six types of plant dyes available in Sarawak, Malaysia, namely, Engkerabai leaves (Psychotria viridiflora), Ketapang leaves (Terminalia catappa), mangrove bark (Ceriops tagal), Sepang wood (Caesalpinia sappan), mangosteen husk (Garcinia mangostana) and onion skin (Allium cepa). Then, the dyed samples were immersed in vitamin C. The dyed and vitamin C-treated silk samples were exposed to direct sunlight for 40 h to test whether vitamin C had any effect on the light fastness of the dyed samples.

Findings

It was found that the fabric samples using vitamin C for after-treatment, particularly Engkerabai, Ketapang, mangrove and mangosteen, exhibited better light fastness. The colours of the four samples changed and looked darker when compared to the non-treated fabric samples. However, it was observed that vitamin C had a reverse effect on Sepang wood and onion skin. The acidic aqueous solution of vitamin C discharged the dyed samples instead.

Originality/value

In conclusion, depending on the plant types, vitamin C can be used to improve the light fastness of natural dyes or as a reducing agent for natural dyes.

Article
Publication date: 17 July 2009

A. Uckiah, D. Goburdhun and A. Ruggoo

This paper aims to determine the effects of processing pineapple fruits into different products and storage of the processed products on the ascorbic acid content.

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Abstract

Purpose

This paper aims to determine the effects of processing pineapple fruits into different products and storage of the processed products on the ascorbic acid content.

Design/methodology/approach

Pineapples (variety “Queen Victoria”) were processed into juice, jam and sorbet. Vitamin C was analysed by the 2‐6 dichloroindophenol titrimetric method and tests were performed during preparation and storage of the products. The pineapple juice was stored for nine days at 8°C, whilst the jam and sorbet were kept for two months at 22‐25°C and −18°C respectively.

Findings

Fresh peeled pineapple fruit contains an average ascorbic acid content of 24.8 mg/100 g of fruit. During the juice making process, peeling led to the highest percentage loss of vitamin C (41.8 per cent) followed by exhausting (23.7 per cent). Processing of pineapples into jam was revealed to be most destructive towards ascorbic acid (a loss of 46.8 per cent) as compared to juice making (38.5 per cent) and sorbet preparation (15.5 per cent). Storage of the three processed products in the specific conditions led to a significant decrease (p<0.05) in vitamin C content, and the highest rate of degradation was in pineapple juice (0.6 mg loss per day).

Originality/value

This paper deals with the retention of vitamin C potency in pineapple products, which is important both to consumers concerned with maintaining good health, and to pineapple processors, who are interested in quality assurance, nutrient labelling and product storage.

Details

Nutrition & Food Science, vol. 39 no. 4
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 14 September 2010

Antoine G. Farhat and Talar M. Fossian

Lebanese meals rich in vitamin C are taken for granted to contain this vitamin without consideration of its losses during the cooking and storing processes. This paper…

Abstract

Purpose

Lebanese meals rich in vitamin C are taken for granted to contain this vitamin without consideration of its losses during the cooking and storing processes. This paper aims to examine the impact of different cooking pots, refrigeration and conventional reheating or via microwaving (MWR) on vitamin C depletion.

Design/methodology/approach

Two samples of three meals rich in vitamin C (AB: Aadas Bhamoud made of lentils and Swiss chard; CS: cauliflower stew; ML: Meloukhieh made of Jew's mallow) were analyzed in triplicates when they were raw, cooked in double based stainless steel (DBSS) or pressure cookers (PCs), refrigerated at 4 C for 48 h, and when reheated in an open pot or in a microwave reaching 70 C. The titration with 2,6‐dichlorophenolindophenol method was used for vitamin C analysis.

Findings

Relative vitamin C losses throughout the processing stages were 37.64, 65.43 and 79.00 percent for ML, CS and AB, respectively. DBSS tended to deplete vitamin C less than PC. AB lost 34.4 and 49.2 percent vitamin C with DBSS and PC, respectively; CS lost 52.3 and 57.5 percent with DBSS and PC, respectively; and ML lost 16.3 and 27.4 percent with DBSS and PC, respectively. Vitamin C loss at refrigeration was significant for both cooking pots used for the meals AB and ML but not for CS. Reheating resulted in further significant losses across meals and reheating methods.

Practical implications

The study highlights the importance of avoiding unnecessary cooking practices to minimize vitamin C depletion and more accurately estimating its daily intake.

Originality/value

The study presents for the first time the quantification of vitamin C losses in Lebanese meals subjected to different processing types and stages.

Details

Nutrition & Food Science, vol. 40 no. 5
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 3 August 2021

Khaled M.M. Koriem and Mahmoud S.S. Arbid

This paper aims to design to evaluate the protective effect of vitamin E to ameliorate the disturbances in testosterone pathway and sperm quality of male rats induced by…

Abstract

Purpose

This paper aims to design to evaluate the protective effect of vitamin E to ameliorate the disturbances in testosterone pathway and sperm quality of male rats induced by the glycosides vicine (V) and convicine (C) of Vicia faba.

Design/methodology/approach

Forty male albino rats were divided into five equal groups; control, paraffin oil, V (400 mg/kg) C (150 mg/kg)-treated group, vitamin E (100 mg/kg) + VC-treated group, and vitamin E (200 mg/kg) + VC-treated groups which injected intraperioneally (IP) with 0.5-ml saline, 0.5-ml paraffin oil,V (400 mg/kg) and C (150 mg/kg) of Vicia faba, vitamin E (100 mg/kg) + VC-treated groups, and Vitamin E(200 mg/kg) + VC-treated groups, respectively. Blood and testicular tissue were obtained after one month of the study. The male genital organs were calculated. Testosterone (Ts), luteinizing hormone (LH), follicle stimulating hormone (FSH), dehydroepiandrosterone sulfate (DHEA-SO4), sex hormone binding globulin (SHBG),?-glutamyl transpeptidase (?-GT), glucose-6-phosphate dehydrogenase (G6PD), 3ß-hydroxysteroid dehydrogenase (3ßHSD), lactate dehydrogenase (LDH), spermatozoa concentration, percent of mortality and abnormal sperms were evaluated.

Findings

The VC-treated group showed significant decrease (p < 0.01) in Ts, DHEA-SO4, G6PD, spermatozoa number and mortality percent, as well as, the male genital organs (testes, epidydemis, seminal vesicle, prostate and vasa deferentia) while significant increase (p < 0.01) was found in LH, FSH, SHBG, LDH, ?-GT, sperms monoclonal Ki-67, and abnormal spermatocytes levels compared with control group. Vitamin E co-injection with VC-treated group returned all these parameters to the normal values. The higher dose of vitamin E (200 mg/kg) was more effect than the lower dose (100 mg/kg).

Originality/value

Vicia faba contains V and C glycosides. The V and C glycosides in Vicia faba are hydrolyzed by intestinal microflora to aglycones divicine and isouramil, respectively. Divicine and isouramil are highly reactive compounds generating free radicals where divicine and isouramil are the main factors of favism. The V and C glycosides induced disturbances in testosterone pathway and sperm quality of male rats and vitamin E ameliorates these disturbances.

Details

Nutrition & Food Science , vol. 52 no. 1
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 1 February 1988

Caroline Austin

Why is the Indian fruit‐eating bat like a human being? asks Caroline Austin. Because they are both incapable of synthesising vitamin C! The disability is the result of…

Abstract

Why is the Indian fruit‐eating bat like a human being? asks Caroline Austin. Because they are both incapable of synthesising vitamin C! The disability is the result of some long‐past mutation in evolution which has resulted in the loss of activity of an enzyme which catalyses the final step in the biosynthesis of vitamin C. Clearly, vitamin C must be supplied in the diet to compensate for this loss, but how much should we take? In recent years there has been a great deal of controversy on this topic

Details

Nutrition & Food Science, vol. 88 no. 2
Type: Research Article
ISSN: 0034-6659

Article
Publication date: 14 September 2015

Nitin Mehta, B . D. Sharma, R. R. Kumar, Pavan Kumar, Om Prakash Malav and Akhilesh Kumar Verma

The purpose of this study is to develop a chicken product that could supply calcium, vitamin E and vitamin C together with high sensory acceptability. The present study…

Abstract

Purpose

The purpose of this study is to develop a chicken product that could supply calcium, vitamin E and vitamin C together with high sensory acceptability. The present study was envisaged to develop low-fat chicken patties fortified with calcium, vitamin E and vitamin C without any adverse effects on sensory attributes.

Design/methodology/approach

Three different levels of calcium lactate as a source of calcium viz. 1.5, 1.75 and 2.0 per cent, α-tocopherol acetate for vitamin E at 0.019, 0.023 and 0.029 per cent and ascorbic acid for vitamin C at 0.09, 0.12 and 0.15 per cent in low-fat chicken meat patties were tried and the optimum level was standardized based on physico-chemical, proximate and sensory parameters.

Findings

The calcium lactate at 1.75 per cent, α-tocopherol acetate at 0.029 per cent and ascorbic acid at 0.15 per cent were found to be optimum on the basis of proximate, physico-chemical and sensory parameters. The textural attributes of the standardized product was comparable to that of the control. The a*, b* and Chroma values for the low-fat chicken patties fortified with calcium, α-tocopherol and ascorbic acid were significantly higher (p < 0.01) than that of the control. The calcium and ascorbic acid concentration of the standardized product was significantly higher (p < 0.01) than that of the control.

Originality/value

The levels in the fortified product were found to be suitable to achieve a 20 per cent RDA of calcium and almost a complete RDA for vitamin C. The research findings demonstrated the development of a single-designer chicken product rich in calcium, vitamin C and vitamin E.

Details

Nutrition & Food Science, vol. 45 no. 5
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 1 March 1973

M. Spencer

The natural colour of green vegetables is due to a mixture of chlorophylls. Under conditions of moist heat, the chlorophyll is converted to an olive green compound…

Abstract

The natural colour of green vegetables is due to a mixture of chlorophylls. Under conditions of moist heat, the chlorophyll is converted to an olive green compound, phaeophytin, as a result of the replacement of an atom of magnesium in the centre of the chlorophyll molecule by two hydrogen atoms. The magnesium attaches itself to one of the natural acids in the vegetable. Hence the colour change is favoured by acid conditions and the addition of sodium bicarbonate can reduce it. This is not altogether desirable since raising the pH accelerates the destruction of vitamin C. However it has recently been shown that if magnesium carbonate and calcium acetate are added to green beans sufficiently to raise the pH by only 0–3 of a unit, the canning process results in twenty per cent less conversion of chlorophyll to phaeophytin than the untreated vegetable. Losses of the green colour are increased with time and temperature, and the conditions necessary to sterilize canned peas produce this colour change. For this reason it is normal in Britain to add artificial green colour to canned peas to give them an attractive appearance.

Details

Nutrition & Food Science, vol. 73 no. 3
Type: Research Article
ISSN: 0034-6659

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