Cereals riboflavin

The enrichment program followed in the United States is (/) the enrichment of flour, bread, and degerminated and white rice using thiamin [59-43-8] C 2H y N O S, riboflavin [83-88-5] C2yH2QN4Na02P, niacin [59-67-6] CgH N02, and iron [7439-89-6]-, (2) the retention or restoration of thiamin, riboflavin, niacin, and iron in processed food cereals (J) the addition of vitamin D [67-97-0] to milk, fluid skimmed milk, and nonfat dry milk (4) the addition of vitamin A [68-26-8], C2qH2qO, to margarine, fluid skimmed milk, and nonfat dry milk (5) the addition of iodine [7553-56-2] to table salt and (6) the addition of fluoride [16984-48-8] to areas in which the water supply has a low fluoride content (74). 

Milk, milk products, and foods of animal origin contain high amounts of (free) riboflavin with good bioavailability. In foods of plant origin, the majority of riboflavin is protein-bound and therefore less bioavail-able. Cereal germs and bran are plant sources rich in riboflavin [1]. 

Vitamins occur naturally in many foods and raw materials. However the natural contents are often supplemented in many food products to ensure an adequate intake, for example in infant formulae, breakfast cereals and clinical nutrition products. Vitamins are usually added as nutrients and thus not covered in this chapter but may also be added as food colours (riboflavin, carotenes). The reader should refer to the following references for recent developments in... 

Riboflavin is also known as vitamin B2. It contains a complex isoalloxazine ring that humans are unable to synthesize. The complex ring is hooked onto a live-carbon sugar derivative, ribitol, closely related to the ribose that occurs in RNA. The RDA for adult males is 1.3 mg/day and for adult females 1.1 mg/day. Values decrease with increasing age but increase in pregnancy and lactation. Organ meats, milk, bread products, and fortified cereals are substantial sources of riboflavin. 

Riboflavin (vitamin B2) is found in liver, milk, meat, green vegetables, cereals and mushrooms. It is active in the form of two coenzymes, flavin mononucleotide and flavin adenine dinucleotide. As a coenzyme for proton transfer in the respiratory chain it is indispensable for energy-release from carbohydrates, lipids and proteins. Riboflavin deficiency only occurs in combination with deficiencies of other members of the vitamin B family. The symptoms of such deficiency consist of angular stomatitis, lesions of the cornea, dermatoses and normochromic normocytic anaemia. 

Potatoes are an excellent source of carbohydrates and contain significant amounts ofphosphorus, potassium, calcium, and vitamins, especially vitamin C. Potato protein content, at over 10%, is relatively close to that of wheat flour (11%) also, thanks to their lysine, methionine, cystine and cysteine contents, potatoes are a valuable supplement to cereal proteins. For instance, potatoes provide a significant source of proteins (10-15% of total requirements), a major source of vitamin C, an important source of energy, and also minerals like iron and other vitamins such as thiamin, nicotinic acid, riboflavin, and pro-vitamin A (p carotene) (Salunkhe and Kadam, 1991). 

Enriched cereals are high in iron, niacin, thiamine, and riboflavin, along with other B vitamins... 

As with the main cereals, faba beans are a relatively poor source of Ca and are low in iron and Mn. The P content is higher than in canola. Faba beans contain lower levels of biotin, choline, niacin, pantothenic acid and riboflavin, but a higher level of thiamin, than soybean meal or canola meal. 

Bread and cereals provide thiamin, riboflavin, niacin, pyridoxine, folate, pantothenic acid, and biotin. 

We are of the opinion that at least in young women such as those we have studied, riboflavin requirements of females who are undertaking aerobic exercise can be met by normal food sources of riboflavin. Rich food sources of riboflavin in the U.S. diet include milk, cheese, yogurt, fortified breakfast cereals, and to a lesser extent, enriched bread. The riboflavin content of commonly consumed foods is shown in Table I. We assume, however, that it might be difficult for exercisers to meet their riboflavin requirements if for one reason or another they were unable to consume milk or other dairy products. 

Vitamin B complex is the collective term for a number of water-soluble vitamins found particularly in dairy products, cereals and liver.Vitamin B (thiamine) is used by mouth for dietary supplement purposes and by injection in emergency treatment of Wernicke-Korsakoff syndrome. Vitamin B2 (riboflavin) is a constituent of the coenzyme FAD (flavine adenine dinucleotide) and FMN (flavine mononucleotide) and is therefore important in cellular respiration. Vitamin Be (pyridoxine) is a coenzyme for decarboxylases and transamination, and is concerned with many metabolic processes. Overdose causes peripheral neuropathy. It may be used medically for vomiting and radiation sickness and for premenstrual tension. Pyridoxine has a negative interaction with the therapeutic use of levodopa in parkinsonism by enhancing levodopa decarboxylation to dopamine in the periphery, which does not then reach the brain. The antitubercular drug isoniazid interferes with pyridoxine, and causes a deficiency leading to peripheral neuritis that may need to be corrected with dietary supplements. Vitamin B ... 

B2 Riboflavin Milk, enriched breads and cereals, liver, lean meat, eggs, leafy green vegetables Male 1.4-1.7 mg Female 1.2-1.3 mg Preg 1.6 mg Lact 1.8 mg... 

Riboflavin-5 -phosphate sodium salt is much more soluble in water than the unesterified riboflavin and is not so intensely bitter. It is one of the physiologically active forms of vitamin B2. It is more unstable to light than riboflavin. Both forms can be used as coloring and an enriching food additive to cereal, dressing, and cheese. 

Riboflavin (vitamin B ) (i) Ravin mononucleotide (li) Flavin adenine dinucleolide Hydrogen Hydrogen (i) Riboflavin Cereals Cornsteep liquor Cottonseed flour... 

At present, over 3000 tons of riboflavin are industrially produced each year. About 70% of this material is used as feed additive in the form of free-flowing, spray-dried granules or microgranules. The remaining 30% are required for the fortification of foods like breakfast cereals, pastas, sauces, processed cheese, fruit drinks, vitamin-enriched milk products, baby formulas, and clinical infusions. 

Riboflavin (vitamin B2) is determined in a cereal sample by measuring its fluorescence intensity in 5% acetic acid solution. A calibration curve was prepared by measuring the fluorescence inteiisities of a series of standards of increasing concentrations. The following data were obtained. Use the method of least squares to obtain the best straight line for the calibration curve and to calculate flie concentration of riboflavin in the sample solution. The sample fluorescence intensity was 15.4. 

Riboflavin has a wide distribution in foods, and small amounts are present as coenzymes in most plant and animal tissues. Eggs, lean meats, milk, broccoli, and enriched breads and cereals are especially good sources. A portion of our niacin requirement can be met by synthesis from tryptophan. Meat (especially red meat), liver, legumes, milk, eggs, alfalfa, cereal grains, yeast, and fish are good sources of niacin and tryptophan. 

Zandomeneghi M, Carbonaro L, Calucci L, Pinzino C, Galleschi L, Ghiringhelli S. 2003, Direct fluorometric determination of fluorescent substances in powders the case of riboflavin in cereal flours. Journal of Agricultural and Food Chemistry 51, 2888-2895. 

Sources. Riboflavin is found in a variety of foods, including dairy products, meat, vegetables, and cereals. Therefore, riboflavin deficiency is uncommon in Western countries. Riboflavin is easily destroyed by exposure to light. Up to 50% of the riboflavin in milk contained in a clear glass bottle can be destroyed after 2h of exposure to bright sunlight. 

Riboflavin is commonly determined fluorimetri-cally, for instance in milk, by its strong native fluorescence at pH 7, which arises from the extended conjugation and rigidity of the nonribose portion of the molecule. Another fluorimetric method involves conversion of riboflavin into its fluorescent derivative lumiflavin using ultraviolet (UV) irradiation. Mixtures of thiamin and riboflavin in foods such as cereal products have been resolved using LC with fluorimetric detection. 

Microwave extraction provided an efficient online method for the liberation of flavins from complex food matrices. Because of the acidic medium used and the microwave power, the conversion of flavins from one form into another occurred after liberation from the sample matrix and 100% conversion of FAD to FMN after extraction was observed. Some conversion of FMN into riboflavin was also observed (about 15.2%). This was taken into account when analyzing samples where the FMN content was determined by increasing the figure reported by 15%. For those products in which FMN was not detected no assumptions could be made. The method was compared with the AOAC fluorimetric method commonly applied for milk and cereal samples, with recoveries of 94-106% for spiked riboflavin. 

Riboflavin and other flavinoids are found in dairy produce and meat and to a lesser extent in cereals. The RDA is 1.6-2.0 mg. Flavins are stable to heat and acid but destroyed by exposure to light. UV irradiation of riboflavin in acid or neutral solution gives rise to the fluorescent compound lumichrome, whereas in alkaline solutions irradiation produces lumiflavin. Flavins are required in the body as their coenzymes flavin mononucleotide and flavin adenine dinucleotide, which are involved in redox reactions involving one- and two-electron transfers and linked to many energy-dependent processes in the body. 

Thiamine was analyzed by HPLC in rice, cereals, meat, and other byproducts. In these systems, thiamine could be determined simultaneously with riboflavin and niacin. 

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