vitamin_C-temperature.pdf - KALEEM ET AL(2016 FUUAST J BIOL...

This preview shows page 1 - 2 out of 4 pages.

KALEEM ET AL (2016), FUUAST J. BIOL., 6(1): 117-120INVESTIGATION OF THE EFFECT OF TEMPERATUTE ON VITAMIN C IN FRESH AND PACKED FRUIT JUICES AFSHAN KALEEM*, HUMAIRA NAZIR, SAMRA PERVAIZ, MEHWISH IQTEDAR, ROHEENA ABDULLAH, MAHWISH AFTAB AND SHAGUFTA NAZ Department of Biotechnology, Lahore College for Women University, Lahore, Pakistan* Corresponding author e-mail: [email protected] Abstract Vitamin C in different juice samples, including fresh and packed juices, was investigated. The melting temperature of vitamin C is above 100 °C suggesting that boiling of vegetables does not destroy vitamin C, but the vitamin becomes dissolved in the boiling water. When juices are preserved and packed much vitamin C is lost. Redox titration was utilized for determination of vitamin C in the different samples. Highest amount of vitamin C content was observed in fresh lemon, whereas fresh apple, orange, pineapple, mango, water melon, melon and tomato showed low levels. The effect of temperature was highest in fresh lemon. In packed juices the same tendency was observed, though the content of vitamin C was found to be less than in fresh juices. Introduction Fruits have a high content of fibre and vitamins, and are low in calories and fat. Fruits healthy properties are beneficial because of their content in vitamins, anti-oxidant, micro-nutrients and minerals, which is helpful in prolonging of life by protecting and rejuvenating tissues, cell and organs. It protects from aliments like hair-fall, wrinkling of skin, memory loss and age-related macular degenerating of the retina in the eyes, cancer, Alzheimer’s disease, osteoporosis amongst others. Vitamin C, also known as ascorbic acid, is a water-soluble vitamin. L-ascorbic acid is the biologically-active form of Ascorbic acid (Novakova et al.,2008). Ascorbic acid is quickly oxidized to dehydro-ascorbic acid (DHA) because of two hydroxyl groups in its structure. Several studies show a reduced risk of cardiovascular diseases is associated with a a higher intake of vitamin C from either diet or supplements (Liu, 2013). In cancer patients intravenous pharmacological doses of vitamin C are normally well tolerated. In addition vitamin C is also known to be vital for many biological processes such as in absorption of inorganic iron, inhibition of nitrosamine formation, collagen formation, reduction of plasma cholesterol level, enhancement of the immune system (Getoff, 2013). Vitamin C is available in natural and synthetic L-ascorbic acid, and is chemically identical (Gregory, 1993). Water content is 7090% in mostly fruits and vegetables, when they are separated from their nutrient source (tree, plant, or vine) they undergo respiration, which result in loss of moisture, degradation of nutrients and potential microbial spoilage. In some cases, immature harvesting of fruits and vegetables is done to decrease mechanical damage during harvesting and transportation. Moreover particular cultivar, type of soil, production system (conventional, organic, etc.), and weather conditions (humidity, temperature, daylight hours, etc.) affect

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture