Riboflavin Content Research Articles

Sugar beet responses to iron nutrition and stress

Abstract Sugar beets were grown at four concentrations of added Fe (0.00, 0.02, 0.2 and 2.0 mg L‐1) in nutrient solutions. The pH increased similarly in solutions at the two higher Fe concentrations and decreased moderately and negligibly respectively at the lowest added Fe and no Fe concentrations. Chlorosis was pronounced in plants of the latter two treatments and was accompanied by marked reductions in the chlorophyll content of apical leaves, in the size of young expanded leaves, and in the fresh and dry mass of roots and shoots. The decreases in these parameters were greater for plants at no Fe than at 0.02 mg Fe L‐1 The riboflavin content in the nutrient solutions increased only negligibly with maximum iron, increased slightly with 0.2 mg Fe L‐1, and increased substantially with 0.02 mg Fe L‐1 and no Fe, but was lower in the latter. The cumulative amounts of riboflavin excreted and the times of maximum excretion varied within replicates of solutions containing both low Fe and no Fe. The maximum ribo...

Amino acid composition protein quality and water-soluble vitamin content of germinated cowpeas (Vigna unguiculata).

Amino acid composition, protein digestibility, calculated protein efficiency ratio (C-PER and DC-PER), chemical scores and water-soluble vitamin content of cowpea seeds germinated at 25 degrees C or 30 degrees C for 24 h were determined. Also, the effect of processing steps (heated-air drying, decortication and cooking) on these parameters were examined. Germination had little effect on amino acid profile of cowpeas. In vitro protein digestibility was not improved significantly by germination nor by decortication but was improved by cooking. C-PER and DC-PER ranged from 1.95 to 2.21 and from 1.63 to 1.82, respectively. DC-PER compared well with reported rat PER of cowpea products and seemed more sensitive than C-PER. Based on whole egg values, chemical scores ranged from 37.7 to 45.8% (mean +/- SD; 42.2 +/- 2.4%). Germination increased the contents of niacin, thiamin and riboflavin significantly. Decortication resulted in up to 30% loss in niacin while thiamin content was reduced 41% by cooking.

Riboflavin Requirement of Turkey Poults Fed a Corn-Soybean Meal Diet from 1 to 21 Days of Age

Two battery experiments involving a total of 816 Nicholas Large White turkey poults were conducted to determine the riboflavin requirement from 1 to 21 days of age. In Experiment 1,480 poults were assigned to six dietary treatments: 0, .6, 1.1, 1.7, 3.1, and 4.4 mg supplemental riboflavin/kg basal diet. The corn-soybean meal basal diet was formulated to contain 28.5% crude protein. The vitamin premix was formulated to be devoid of riboflavin. The analyzed riboflavin content of the basal diet was 2.7 mg/kg feed. Ten replicates of eight birds per pen (four female and four male poults) were used per diet. In Experiment 2, 336 poults were assigned the same dietary treatments but with only seven replications. Using the broken line technique, it was determined that .79 ± .03 mg supplemental riboflavin/kg diet or 3.5 mg riboflavin/kg diet was needed to maximize growth. However, in order to prevent leg paralysis, slightly more riboflavin appeared to be needed.

EFFECT OF GAMMA RAY IRRADIATION AND FRYING ON THE THIAMINE CONTENT OF BACON

ABSTRACTThe effects of ionizing irradiation and frying on the thiamine and riboflavin content of bacon were determined. Significant destruction of thiamine but not riboflavin occurred during both the irradiation and frying. The destruction of thiamine was found to be directly related to the dose of ionizing radiation or the degree of cooking. Frying before irradiation, reduction of water content by lyophilization, and irradiation at ‐ 40°C rather than 2°C produced significantly greater retention of thiamine. Frying the bacon following irradiation produced radiation dose‐related, nonadditive, increased destruction of thiamine. The protective effect of frying before irradiation was not directly linked with the reduction of moisture by frying.

Industrial processing of palm juice and riboflavin loss

The effect of processing or season, or exposure to atmospheric temperature on riboflavin content of industrially bottled palm juice was studied. Losses occurred in riboflavin content throughout the processing stages but loss was more pronounced after the filtration stage. The pasteurized palm juice contained about 60% of the initial riboflavin while the riboflavin content of fermenting palm juice increased significantly (P < 0·01) with time of exposure. Losses occurred in pasteurized ‘non-fermenting’ samples similarly exposed. On the other hand, losses were not observed in pasteurized samples stored in the dark for 6 weeks. Sun-inactivation may explain the significantly lower riboflavin content of samples processed in the dry compared to those processed in the rainy season. Findings from the study suggest that the nutritional value of processed palm juice may be raised if fermentation is allowed to proceed for 10 h before processing commences. Also, synthetic riboflavin may be incorporated at the pasteurization stage in non-fermenting juice.

Effect of Gamma Irradiation on the B Vitamins of Pork Chops and Chicken Breasts

A study was made of the effect of low-dose gamma irradiation on the content of thiamine (B1), riboflavin (B2), niacin, pyridoxine (B6) and cobalamin (B12) in pork chops, and thiamine, riboflavin and niacin in chicken breasts. Gamma irradiation from a caesium-137 source was used to irradiate the samples in a range of 0.49 to 6.65 kGy from -20 to +20 degrees C. Over the range of dose and temperature studied it was possible to derive a mathematical expression for predicting the losses. A calculation was made of the effect of the loss of thiamine, riboflavin and niacin due to irradiation on the overall loss of these vitamins in the American diet. The losses of riboflavin and niacin were of the order of a fraction of a per cent. Pork is an important source of thiamine, but the calculated loss at 1.0 kGy of this vitamin in cooked pork was only 1.5 per cent. There were initial increases with radiation doses up to 2-4 kGy in the measured concentrations of riboflavin and niacin in both pork and chicken. The increases were highly significant, and are of concern both to the study of radiation effects and the chemical method of the determination of these two vitamins.

Effect of soaking and germination temperatures on selected nutrients and antinutrients of mungbean

Effects of different temperatures, during soaking and germination on selected nutrients and antinutrients of mungbean, were studied. Comparison of the coefficients of variability revealed striking differences in their values as a result of soaking and germination. Soaking at 55°C resulted in larger decreases in the phytate and trypsin inhibitor activity than at 27°C whereas protein was little affected. Biosynthesis of protein, ascorbic acid and riboflavin was generally greater, and biodegradation of phytate and trypsin inhibitor higher, during germination at ambient conditions (20–35°C) than at low temperature (20°C) while thiamine and amino acid contents were less affected. Maximum contents of ascorbic acid ( 47·0 mg 100 g ), riboflavin (3·54 μg/g) and thiamine (4·37 μg/g) were detected during germination for 48–72 h irrespective of temperature. A slight increasing trend in the protein content (18·4–23·5%) but decreasing trends in the phytate ( 105–216 mg 100 g ) and trypsin inhibitor (497–2460 TIU/g) values, were observed during germination regardless of the temperatures tested.

The B vitamin content of hospital meals and potential low intake by elderly inpatients

The content of thiamin, riboflavin, vitamin B6 (pyridoxamine, pyridoxal, pyridoxine), niacin and total folate were determined in the meal choices comprising a typical day's menu in a teaching hospital. Thiamine, riboflavine, and B6 were measured by HPLC analysis, folate by microbiological assay, and niacin content was calculated from food tables.The results were compared with UK Recommended Daily Amounts (RDA) whenever possible (thiamine, riboflavine and niacin). Vitamin B6 and folate results were compared with the US Recommended Daily Dietary Amount (RDDA) as no British recommendation was available.Elderly inpatients selected meals which, even if completely consumed, provided half the current recommendation for vitamin B6 and one‐third of the recommendation for folate. More than half the meal selections provided less than recommended amounts of riboflavine, and in a quarter of cases less than the recommended amount of thiamine.

Riboflavin Requirement of Broiler Chicks Fed a Corn-Soybean Diet

Two 21-day battery experiments were conducted with day-old broiler chicks fed a corn-soybean meal diet to re-evaluate the riboflavin requirement for optimum performance. In each experiment a total of 384 birds was assigned to six dietary treatments and given 0, 0.9, 2.0, 2.8, 3.6, or 4.4 mg of supplemental riboflavin/kg of feed. The corn-soybean meal diet was formulated to contain 22% CP and 3,200 kcal of ME/kg of feed. The analyzed riboflavin content of the unsupplemented diet was 2.6 mg/kg. A severe leg paralysis (inability to walk and to move one or both legs) was first observed between 10 to 12 days of age in birds receiving no supplemental riboflavin. Besides leg paralysis, high mortality and poor growth were the main signs of riboflavin deficiency observed. A minimum requirement for growth of 3.6 mg of riboflavin/kg of feed was determined using the broken-line technique. However, in order to prevent signs of leg paralysis, the minimum requirement of 4.6 mg riboflavin/kg of feed was suggested. Based on the maximum feed intake (834 g) observed for birds to reach maximum body weight (593 g) at 21 days of age, a minimum intake of approximately 6.5 μg riboflavin/g body weight was needed for maximum performance.

Bread Formulation Designed for the Elderly Using Response Surface Methodology

ABSTRACTThe effects of five levels of acid whey, a Torula yeast product and low fat processed American cheese on the flavor of bread were evaluated by an experienced sensory panel. From these data, response surface contour plots were drawn, and a formula was indentified which resulted in a bread with characteristics that were liked by 50 individuals 65 years of age or older. This formula. increased the calcium, thiamin and riboflavin content by 1.2, 2.0 and 1.2 times, respectively, over that of the best‐liked commercial bread.

Riboflavin requirement of lactating swine.

Twenty-five crossbred gilts and 25 crossbred sows were used in an experiment to estimate the riboflavin requirement of lactating swine. During gestation the females were fed a 12% crude protein, corn-soybean meal diet that was marginal in riboflavin content, i.e., 2.3 mg/kg. After farrowing, litter size was equalized across lactation diets within each parity category. The basal, 14% crude-protein corn-soybean meal lactation diet was supplemented to provide five levels of dietary riboflavin: 1.25, 2.25, 3.25, 4.25 and 5.25 mg/kg. Five gilts and five sows were fed each dietary treatment. Each dam was provided her assigned diet ad libitum during the 24-d lactation; piglets were not provided supplemental feed. The erythrocyte glutathione reductase activity coefficient (EGRAC), an indicator of riboflavin status, was measured on blood samples obtained from the dams and their piglets on d 1 and d 24 postpartum. On d 1, the mean EGRAC of gilts was slightly higher than that of sows, while piglet EGRAC was similar regardless of maternal age. On d 24 gilts and their piglets had higher average EGRAC (P less than .01) than did sows and their piglets. Thus, there was a treatment x dam age interaction (P less than .05). Lactation performance criteria gave further evidence of similar treatment x age group interactions. Gilts fed the diet containing 1.25 ppm riboflavin had higher piglet mortality, consumed less feed and lost more weight (P less than .05) for each criterion than did sows fed the same diet. Despite these observations, the broken-line estimates of the riboflavin requirement, based on EGRAC, for gilts and sows were 16.3 and 16.2 mg/d, respectively. The EGRAC values for piglets closely paralleled those of their dams regardless of treatment, suggesting that there is no mechanism to protect the nursing piglets from a maternal dietary deficiency of riboflavin.

Effect of Fluorescent Light on Flavor and Riboflavin Content of Milk Held in Modified Half-Gallon Containers

A study was conducted to evaluate the ability of aluminum and oriented polypropylene film to protect milk in half-gallon polyethylene containers from light radiation and thereby stabilize it from light-induced off-flavor (LIOF) and riboflavin loss. Both films, applied to the major portion of the outer surface of the containers, protected milk from light radiation better than when applied only to the container top.

Changes in lens and erythrocyte glutathione reductase in response to exogenous flavin adenine dinucleotide and liver riboflavin content of rat on riboflavin deficient diet

The effect of exogenous flavin adenine dinucleotide (FAD) and hepatic level of riboflavin on the activity of lenticular and erythrocyte glutathione reductase (GSH-R) was studied in rats fed a diet deficient in riboflavin. By 75 days of feeding, the GSH-R activity, under basal condition (in the absence of exogenous FAD) and the activation coefficient (AC, activity of the enzyme in response to exogenous FAD to that without it) values were significantly altered in lens as well as erythrocytes of rats fed riboflavin deficient diet. Significant reduction in riboflavin content of liver was also observed in the experimental animals. These findings suggest that the AC value for the lenticular GSH-R is as equally a reliable biochemical parameter for assessing riboflavin nutriture as that of the erythrocyte enzyme.

Nutrient Composition, Protein Quality, and Sensory Properties of Thirty‐Six Cultivars of Dry Beans (Phaseolus vulgaris L.)

ABSTRACTThirty‐six cultivars representing eight types of dry beans (Phaseolus vulgaris L) were analyzed chemically for content of moisture, fat, ash, total nitrogen, iron, zinc, calcium, magnesium, potassium, phosphorus, thiamin, riboflavin, and amino acids. Protein quality was evaluated using Tetrahymena pyriformis W. Cooked beans were subjected to sensory evaluation and shear‐force measurement. Nutrient concentrations were similar to values reported by earlier investigators. Protein quality ranged from 60% (Red Kidneys) to 90% (Pintos) that of casein. Pintos Nodak and Fiesta and Hyden Navy beans were most acceptable in flavor and texture; Bonus Small White was least acceptable. Cooperation between bean breeders and nutritionists will enable early screening of segregating hybrid populations for desirable nutritional and sensory qualities.

An Assessment of Light-Induced Off-Flavors in Retail Milk

Samples of whole and skim milk from two local dairy plants that were packaged in 3.8-L plastic containers (nonreturnable high density polyethylene) and 1.9, .95, and .48-L fiberboard containers and displayed in the dairy cases of four local grocery stores under normal fluorescent light were analyzed for light-induced changes in flavor and riboflavin content. Milk samples were analyzed daily for flavor, odor, appearance, and riboflavin content. Sensory evaluation was by 25 untrained panelists, and riboflavin was determined by HPLC method. Milk samples were analyzed first in summer, then repeated in winter. Data indicated that under typical production and storage conditions in the area, type and size of container, fat content, and season of production had no major damaging effects on flavor, odor, appearance, or riboflavin content of retail milk.

Light-Induced Changes in Taste, Appearance, Odor, and Riboflavin Content of Cheese

Light-induced changes in taste, appearance, odor, and riboflavin content of common cheeses stored under controlled laboratory conditions and in the dairy cases of four local grocery stores were investigated. Sensory evaluation was performed by 25 untrained panelists, and the riboflavin content was determined by HPLC method. The data obtained from controlled storage indicated that light intensity, type of packaging paper, and piece thickness affected riboflavin retention and color in stored cheese. However, under the display conditions used in the four local stores, retail cheese retained its riboflavin after a display time of 14 d with no significant change in taste, appearance, or odor.

Compositional Analysis of Commercial Whey Drinks

Seven different whey-based beverages, including six commerical products from Europe and an experimental laboratory prototype, were analyzed for protein, carbohydrate, and other main components and for selected micronutrients. The labelling information available and the various tests carried out illustrated several aspects of the current whey drink technologies, including the choice of sweet, acid, or deproteinated whey; the use of variable amounts of whey, water, and fruit juice components; and inclusion of various sweetening agents. The products analyzed included clear, carbonated beverages that showed no sedimentation tendency, as well as products manufactured from unmodified whey resulting in various degrees of sedimentation upon centrifugation. The calcium and riboflavin content in some of the products was comparable to fluid milk, thus indicating that these beverages could be recommended especially for consumers with limited milk consumption habits.

Impact of Infrared Broiling on the Thiamin and Riboflavin Retention and Sensory Quality of Salmon Steaks for Foodservice Use

ABSTRACTSalmon steaks were broiled using infrared radiation and compared to convection oven baking. Total percent cooking losses of moisture and fat content were not significantly different. Samples broiled by infrared oven retained 87.2% and 92.6% of thiamin and riboflavin content, respectively. There were no significant differences for vitamin retention by both methods. Appearance and color of salmon steaks baked in the convection oven were rated significantly higher than infrared broiled samples. Tenderness and juiciness scores for infrared broiled steaks were significantly higher than those for convection oven baked steaks. There were no significant differences in panel scores for odor, flakiness, flavor and overall acceptability of steaks prepared by both methods.

Mycoflora and vitamin content of sun-dried food condiments in Nigeria.

The fungi most frequently isolated (of 20-100% incidence) from fresh okra, pepper fruits and melon seeds are Botryodiplodia theobromae, Rhizopus stolonifer, Trichoderma harzianum, Mucor mucedo and Fusarium oxysporum. The major mycoflora of the fruits which had been sun-dried for twenty days are comprised of Aspergillus spp and Penicillium spp which initially had formed the minor components (of less than 20% incidence) of the colonising population. The effect of sun-drying on the fruits was a statistically significant (P = 0.05) decrease in the riboflavin content and a generally small and non-significant decrease in the concentrations of thiamine, niacin, biotin and ascorbic acid. The effect of mouldiness during sun-drying was to further decrease the concentration of the vitamins.

Partial Purification of an Antioxidizing Component in Raw Cow Milk

ABSTRACTGel filtration was used to partially purify the antioxidizing component of a centrifuged serum of raw cow milk, and its properties were studied. The antioxidizing effect did not decrease after dialysis or heating. The finding of no change after dialysis suggested that the compound was of high molecular weight, estimated at 38,000 by gel filtration. The antioxidizing effect decreased with irradiation, accompanied by a parallel decrease in the riboflavin content. The antioxidizing component of this serum fraction may be a protein‐bound riboflavin.