The nutritional quality of some oat varieties cultivated in Norway

The chemical composition, yield values, and protein quality were measured in 12 oat varieties cultivated in Norway. The protein quality was based on amino acid composition and true protein digestibility, biological value, net protein utilization, and utilizable protein obtained in N-balance experiments with rats. The protein concentration in dry matter varied from 10.25% to 15.69% while fat varied from 5.70% to 10.41%. The variation in readily soluble carbohydrates, crude fiber, ash, and tannin was relatively low. Dry matter yield per hectar varied from 1675 to 6222 kg. The yield of protein, fat, and essential amino acids was also highest in the variety with the highest yield. True protein digestibility was above 90% in all varieties while the biological value was in the range of 74.5%–79.6%. In contrast to most other cereal grains, protein quality was not affected by protein concentration. This resulted in utilizable protein above 10% for several of the oat varieties.     

Nutritive quality and energy yield of high oil,opaque-2 and waxy maize hybrids compared to normal maize hybrids

Grain yield, chemical composition, protein quality and digestible energy were measured for 18 maize varieties (opaque-2, high oil, waxy hybrids, normal hybrids) cultivated in Yugoslavia. Protein quality assessment was based on amino acid composition, and true protein digestibility, biological value, net protein utilization and utilizable protein as determined in nitrogen balance experiments with rats. The protein concentration in dry matter varied from 8.63–18.81% while the fat concentration varied from 4.45–16.13%. There were only minor differences in ash and crude fibre, while starch and sugar varied inversely to fat and protein concentration. Lysine levels were approximately 30% higher for the opaque-2 varieties compared with normal maize, while leucine levels were about 30% lower. Yields were extremely high for all varieties with the highest value being 10.3 tonnes/ha. Due to the high yields, protein production/ha was high in range of 822–977 kg. This resulted in high yields of amino acids/ha. Protein utilization was very high in the opaque-2 varieties, which had the highest lysine contents. The biological values were close to 80 in these varieties, whereas they were only 60–65 in the normal maize varieties.     

Chemical,nutritional and technological characteristics of buck wheat and non-prolamine buckwheat flours in comparison of wheat flour

Chemical, nutritional, and technological characteristics of buckwheat and non-prolamine buckwheat flours in comparison to wheat for celiac patients use have been studied. The results suggested the following conclusions: the 56.5% extraction value for flour obtention is considered good; the buckwheat flour presents methionine and cystine as first limiting amino acids followed by threonine as the second limiting amino acid; the buckwheat flour presents higher content of lysine amino acids than the wheat flour; the buckwheat flour is superior to the wheat flour regarding iron, copper, and magnesium minerals; the buckwheat flour does not present haemagglutinin activity and the tannin content is negligible. Rheological assays indicate that the buckwheat flour does not contain gluten.     

Digestibility of protein and amino acids in selected foods as determined by a rat balance method

Values (%) for true digestibility of crude protein and individual amino acids in 20 selected foods were determined by the rat balance (fecal) method. The products were fed as the sole source of protein in diets containing 8% crude protein (N × 6.25). Lowest true protein digestibility values (79–84) were obtained for pinto beans, kidney beans and lentils; intermediate values (89–92) were obtained for chick peas, beef stew, skim milk (over heated), rolled oats, whole wheat cereal, and pea protein concentrate; and highest values (94–100) were obtained for sausage, macaroni-cheese, rice-wheat gluten cereal, skim milk, tuna, soy isolate, peanut butter, chicken frankfurters, beef salami, casein and casein + methionine. In animal foods, peanut butter and soy isolate, the differences between true digestibility of crude protein and most individual amino acids were less than 5%. However, the values for true digestibility of methionine and cystine were up to 44% lower than those of crude protein in pinto beans, kidney beans, lentils, chick peas and pea concentrate. In these legumes, digestibility of crude protein was not a good predictor of digestibility of the limiting amino acids.     

Processing of maize germ oil cake into edible food grade meal and evaluation of its protein quality

The commercial oil cake produced during expeller pressing of maize germ, was extracted with n-hexane and 80 percent ethanol followed by seiving to remove undesirable materials. In defatted maize germ oil cake (DMGOC): protein, starch, fat, crude fiber (CF) and ash were respectively 24.69, 36.55, 5.68, 7.56 and 3.90 percent and they decrease after processing except ash, which increased slightly. It contains better quality protein having only 3 percent zein and 47 percent albumin. Its amino acids like lysine and tryptophan and biological value (BV) were higher than that of whole maize grain, and was comparable with that of the amino acid requirement of preschool children and casein diets both. Its digestible energy (DE) was lower compared with whole maize grain as well as the casein diets. After processing albumin, globulin and zein decreased whereas glutelin and the residual fraction increased. Not much differences were observed in chemical composition and different amino acids, in vitro protein digestibility (IVPD), true digestibility (TD), BV and DE improved after processing.     

Content and quality of protein in proso millet (Panicum miliaceum L.) varieties

Proso millet belongs to the oldest cereals that human is using. Eight varieties of proso millet were cultivated in Ceske Budejovice from 1998 to 2000 and Cerveny Dvur from 1999 to 2000. The crude protein content was determined according to Kjehladl method and amino acid content was determined chromatographically after acid and oxidative acid hydrolysis. Although the protein content of proso (11.6% of dry matter) was similar to wheat, the grain of proso was significant richer in essential amino acids (leucine, isoleucine, methionine) then wheat. Hence, the protein quality of proso (Essential Amino Acid Index) was higher (51%) compared to wheat. The proso grain contained about 3.3 g kg(-1) of the limiting amino acid-lysine. Significant differences in protein and its quality were found among the evaluated proso varieties. The varieties Toldanskoe and Lipetskoe were the most different from the others in protein and amino acid content and Amino Acid Score of individual acids. They had the lowest content and quality of protein. The seed coat of these varieties was red. The amino acid and protein content was significantly influenced by weather during the year. Dry conditions caused an increase of protein but its quality was decreased.     

Content and Quality of Protein in Proso Millet (Panicum miliaceum L.) Varieties

Proso millet belongs to the oldest cereals that human is using. Eight varieties of proso millet were cultivated in Ceske Budejovice from1998 to 2000 and Cerveny Dvur from 1999 to 2000. The crude protein content was determined according to Kjehladl method and amino acid content was determined chromatographically after acid and oxidative acid hydrolysis. Although the protein content of proso (11.6% of dry matter) was similar to wheat, the grain of proso was significant richer in essential amino acids (leucine, isoleucine, methionine) then wheat. Hence, the protein quality of proso (Essential Amino Acid Index) was higher (51%) compared to wheat. The proso grain contained about 3.3 g kg⁻¹ of the limiting amino acid-lysine. Significant differences in protein and its quality were found among the evaluated proso varieties. The varieties Toldanskoe and Lipetskoe were the most different from the others in protein and amino acid content and Amino Acid Score of individual acids. They had the lowest content and quality of protein. The seed coat of these varieties was red. The amino acid and protein content was significantly influenced by weather during the year. Dry conditions caused an increase of protein but its quality was decreased.     

The nutritive value of amaranth grain (Amaranthus caudatus)

The nutritional value of three pale seeded and one dark seeded variety ofAmaranthus caudatus was studied by chemical analyses and in balance experiments with growing rats. Effects of processing: popping, toasting and flaking were also examined. The pale seeds contained about 14% protein, 10% fat, 2.5% ash, 64% starch and 8% of dietary fibre. The black seeds had a much higher content of fibre (16%). The concentration of essential amino acids were high. Lysine ranged from 5.2–6.0 g/16 g N in the grains, and the limiting amino acids were leucine followed by valine or threonine. The grains contained small amounts of tannin (0.3%) and heat-labile protease inhibitor activity, at levels typical of common cereal grains. Digestibility of protein in the pale seeds was high (87%) and quite unaffected by processing. Protein digestibility of the black seeds was lower, and the digestibility was further reduced by toasting. The biological value of the protein was similar in all products, and very high. The content of minerals varied among varieties and was also affected by processing. Phytate: zinc molar ratios were high in most products, and rats fed the amaranth samples with the lowest zinc contents were in negative zinc balance. In general, femur zinc concentrations were rather low. However, amaranth is an unconventional crop which deserves further attention.     

Chemical composition and protein quality of lentils (Lens) consumed in Egypt

Three local cultivars of lentil (Lens) seeds (Giza 9, Family 91, and Family 195) as well as one imported Pakistani variety were studied. Moisture, protein, fat, carbohydrate, ash, fiber, thiamine, riboflavin, amino acids and some protein fractions were determined on the unpeeled and peeled seeds. The protein quality was evaluated by determining the protein efficiency ratio, net protein utilization, biological value, and true digestibility coefficient. All components were increased by peeling, except the ash, the fiber content, and the residual nitrogen content of the insoluble protein fraction. The latter was markedly decreased by peeling. Giza 9 lentil seeds were found to contain the highest protein and thiamine contents. They showed the highest protein quality and proved to be nutritionally superior to other varieties. Generally, the three local cultivars were found to be chemically and biologically superior to the imported Pakistani cultivar.     

Chemical composition, digestibility and antinutritional factors content of two wild legumes: Styphonolobium burseroides and Acacia bilimekii

The chemical composition, digestibility and toxin contents of two wild legumes: Styphnolobium burseroides and Acacia bilimekii, collected in a semi-arid zone of Mexico, were determined. Both legumes had a high fiber content. The seeds of Styphnolobium burseroides had a low protein content (14%), and the pod a high content of reducing sugars. However the seeds of Acacia bilimekii had a high protein concentration (35%). The seed proteins were low in sulphur amino acids and tryptophan in both legumes but were rich in lysine. Trypsin inhibitors and lectins were present in low concentrations; alkaloids and cyanogenic glucosides were not detected. The in vitro digestibility for monogastric animals was low but the same test with ruminal juice showed a high digestibility for both legumes. Based on their chemical composition and digestibility, these legumes could be a good alternative source in the feeding of ruminants.     

Nutritional improvement of lentils,chick pea,rice and wheat by natural fermentation

Effect of natural fermentation process (4 days) on the non-protein nitrogen, crude and true protein, amino acids content and in vitro digestibility of two kinds of legumes (lentils and chick pea) and two kinds of cereals (rice and wheat) was investigated. Non-protein nitrogen increased significantly (p<0.001) in the fermented products. Little increase has occured in the crude protein while no significant change was observed in the fermented true protein samples. It was observed that methionine and cystine which are considered the limiting amino acids in legume seeds were close to those of FAO/WHO patterns. Also, lysine content (the first limiting amino acid in cereals was higher in fermented rice than that of FAO/WHO pattern. Moreover, fermentation process improved significantly, the in vitro digestibility of both legume and cereal products.     

Nutritional evaluation of some commercial wheat varieties grown in Pakistan

The nutritive value of some commercial wheat varieties grown in Pakistan was measured chemically, including amino acid analysis, and biologically in N-balance experiments with growing rats. The protein content ranged from 13.2% in Punjab-83 to 16% in Barani-83. Lysine per 100g protein varied between 2.46 and 2.75%. The available carbohydrate ranged from 67.3 to 74.7%. Iron content was highest in Sonalika while the concentration of zinc and manganese was highest in Sarhad-82. The protein digestibility (TD), biological value (BV) and net protein utilisation (NPU) varied between 92–95%, 56–68% and 53–65% respectively. Level of wheat protein was negatively correlated with available carbohydrate (r=–0.93), lysine per unit protein (r=–0.67) and BV (r=–0.76). The lysine content (g/16gN) of commercial wheat varieties showed a positive correlation (r=+0.95) with the BV. The protein quality was lowered in varieties having higher content of protein.     

Nutritional evaluation of pigeon pea meal

Mineral, amino acid and fatty acid composition of pigeon pea meal were determined by analysis, while with chick essays, availability (true digestibility) of minerals and amino acids in the meal were estimated. Gross energy, metabolizable energy and true protein digestibility experiments were also conducted. Pigeon pea meal had a very high content of potassium, high content of potassium, high content of phosphorus, moderate content of calcium and magnesium and low content of iron, zinc, copper and manganese. Average availability of minerals was 58.09%. Amino acid content was low, especially cystine and methionine. Amino acid availability was 82.32%, lower than amino acid availability of soybean meal (>90%). Pigeon pea lipids were predominantly saturated fatty acids (69.04%) with low content of unsaturated fatty acids (30.69%) and a total absence of linolenic acid. Metabolizable energy content (N-corrected) was 11.08 MJ/kg in raw pigeon pea and 12.03 MJ/kg in toasted pigeon pea meal.     

Nutritional evaluation of spent grains from sorghum malts and maize grit

Potential use of the high protein by-product of beer production from 77% sorghum malt and 23% maize grit was investigated. Red sorghum spent grains (RSSG) and white sorghum spent grains (WSSG) contained 23.4 and 19.3% crude protein (CP), 54 and 43% dietary fiber (NDF), 1.44 and 0.78% ash, 4.5 and 3.2% hexane extract and tannin content of 7.5 and 1.0 mg/g catechin equivalent respectively. Magnesium was the most abundant mineral in both RSSG and WSSG — 185 and 140 mg/kg, respectively. Calcium, zinc, iron and copper were generally low. Both samples contained cadmium 1.12 (WSSG), 1.19 (RSSG) and lead at 1.38 mg/kg. Lysine was the limiting amino acid (chemical score 0.55) in both samples. Other essential amino acids were adequate or surplus. Stearic acid was the predominant fatty acid with varying levels of lauric, myristic, palmitic, and oleic acids in both samples. Feed intake and weight gain were highest in rats fed 26.3% WSSG (contributing 50% of the diet protein) but protein efficiency ratio (PER) and net protein retention (NPR) were highest in diets where spent grains contributed just 25% of the diet protein. True digestibility of diets decreased as dietary fiber content increased such that animals on diets containing 100% spent grain protein (above 20% NDF) lost weight.     

不同燕麦品种的蛋白质营养品质评价

为了解我国燕麦品种的蛋白质营养品质状况,收集了2008-2010年9个产地的54个燕麦品种,采用国际通用的WHO/FAO氨基酸评分模式对其蛋白质营养品质进行评价,并比较了不同产地和不同年份样本间的差异。结果表明,本试验中的燕麦蛋白质含量大多集中在16%～20%,其第一限制性氨基酸为赖氨酸,其次是苏氨酸、含硫氨基酸(蛋氨酸+胱氨酸);必需氨基酸含量占总氨基酸含量的33.14%,接近WHO/FAO推荐的理想蛋白质的必需氨基酸组成模式。不同地区所产燕麦品种的蛋白质品质存在显著差异,从氨基酸评分(AAS)、化学评分(CS)、生物价(BV)等指标可反映出吉林产燕麦的蛋白质营养品质较好,甘肃地区的仅次之,且在粗蛋白含量上更具优势。基于蛋白质营养品质通过聚类分析将所收集的样品分为4类,分类结果与其样品来源有关。     

Protein Nutritional Quality of Infant Cereals during Processing

The most common food for weaning at the age of 4–6 months is cereal since is that it is a good source of high quality protein. However, processing may affect this quality. The aim of the present study was ascertain the changes that take place during four processing stages of infant cereals (in the raw materials, after roasting, after enzymatic treatment and drum drying, and in the commercial product), the following protein nutritional parameters: crude and true protein (CP and TP, respectively), in vitro protein digestibility (IVPD), free amino acids (FAA), calculated protein efficiency ratio (C-PER) and total amino acids profile. Of the infant cereals studied two contained gluten (‘Multicereal’ and ‘Wheat’) and two were gluten-free (‘Growth’ and ‘Rice and carrot’). All the parameters studied were affected by the different processing stages, but none showed a clear trend. The CP and TP content decreased after heat treatment (roasting) with a consequent increase in FAA content due to protein hydrolysis and the release of amino acids. IVPD remained stable during the processing stages in all the infant cereals, except in ‘Wheat’, while C-PER increased significantly. Infant cereals containing gluten showed higher CP and TP contents, and also higher IVPD than gluten free cereals, in which a digestibility value higher than 75% was reached. The overall content of essential amino acids, including sulphur amino acids, was acceptable (equal to or higher than FAO/WHO recommendations), although lysine (Lys) was the limiting amino acid in all the infant cereals.     

燕麦等五种谷物的氨基酸含量综合评价

为了解不同谷物氨基酸的综合质量,测定了燕麦、荞麦、小麦、大麦和水稻等5种谷物的蛋白质和氨基酸含量,并采用主成分分析、聚类分析法进行谷物氨基酸含量综合评价。结果表明,五种谷物中均含有16种氨基酸,总氨基酸含量平均为148.14 g·kg^-1,其中燕麦总氨基酸平均含量最高,为249.93 g·kg^-1;燕麦中支链氨基酸平均含量达到31.23 g·kg^-1,显著高于五种谷物支链氨基酸平均含量(21.84 g·kg^-1)。通过主成分分析,供试材料氨基酸的综合评分表现为燕麦>小麦>荞麦>大麦>水稻。经聚类分析,燕麦的氨基酸含量与其他谷物显著不同。综合来看,燕麦在蛋白质、赖氨酸、支链氨基酸、必需氨基酸、总氨基酸含量和氨基酸六个方面均优于其他4种谷物。     

Comparative study of the chemical composition of wild and cultivated beans (Phaseolus vulgaris)

Five wildPhaseolus vulgaris beans were compared with five cultivatedPhaseolus vulgaris beans in proximate composition, total (true) protein, amino acid composition, and toxic and antinutritional factors. The wild beans contained more protein (25.5% vs. 21.7%), ash (5.15 vs. 4.15%), crude fiber (7.08% vs. 5.04%) compared to cultivated beans while the former contained less fat (0.56 vs. 0.89%) and carbohydrates (61.64 vs. 68.05%). Sulfur amino acids were found to be limiting in both groups of bean as expected; however, the cultivated beans had a higher content of the limiting amino acids. Therefore, the cultivated beans showed a better amino acid profile than the wild beans. Toxic factors were not found in either type of bean; the determinations included saponins, alkaloids, and cyanogenic glycosides. The antinutritional factors investigated were hemagglutinins (lectins) and trypsin inhibitors. The wild beans presented a higher content of trypsin inhibitors (28 TUI per mg) and lectins (9.6) than the cultivated beans did (21 TUI per mg and 7 respectively). From the chemical point of view, domestication seems to be positive; however, the better protein nutritive quality of the cultivated beans should be further confirmed by biological assays.     

The nutritive value of some selected Tanzanian plant food sources

The chemical composition of different varieties of field beans (Vicia faba L.), cowpeas (Vigna unguiculata), groundnuts (Voandzeia subterranea), and sorghum (Sorghum vulgare) were determined. Nutrients analysed in these materials included amino acids, starch, sugar, fibre, minerals and antinutritional factors. All the materials were further tested in balance trials with rats; true protein digestibility (TD), biological value (BV), net protein utilization (NPU) and digestible energy (DE) were evaluated. Based on the chemical analyses as well as on the biological data, the nutritive value of plant materials between species as well as between varieties within species differed considerably. Therefore, more quality evaluation studies along with plant breeding programmes are needed to select the most promising varieties from the nutritional point of view.     

Nutrient composition and biological evaluation of defatted tomato (Lycopersicum esculentus) seed cake

Defatted tomato seed cake was analysed for its nutrient composition and its protein quality was evaluated in 21 day old male rats. The cake is found to be rich not only in protein (40%), minerals like phosphorus, calcium and magnesium but also in crude fiber. Lysine content of the cake protein was in the range of that found in groundnut cake protein. Sulphur containing amino acids were limiting in this protein. However, the protein quality of the cake, as judged by PER and NPU, was relatively lower compared to that of groundnut cake. Its high lysine content (5.1g%) will be of help to improve the cereal based farm animal feed quality.