A method for determining protein content in foodstuffs by 14 MeV neutron activation analysis for nitrogen is described. The
procedure proves to be quite precise, and potentially quite accurate, while only requiring about 7 min per sample. The effect
of interfering activities is discussed, and corrections for30P and38K are described. The protein determinations for over 40 Chinese foodstuffs are given.
Authors:M. Abdel Samei, M. Elshafie, M. Hanna, J. Csikai, and M. Juhász
The protein content of various corn-meals /rice, lupine, sorghum, pumpkin, linseed, water melon, tomato/ collected from Egypt and the USA have been determined by 14 MeV neutron activation analysis via14N/n, 2n/13N reaction. Non-conventional sources like tea and coffee residues were also investigated. The concentrations of trace elements determined by the X-ray fluorescence technique show definite differences even for a given type of seed produced in different geographical regions.
Authors:Marina Vranić, Mladen Knežević, Zsolt Seregély, Krešimir Bošnjak, Josip Leto, and Goran Perčulija
Intensive livestock feeding requires constant monitoring of diet composition to ensure a consistent level of milk or meat production. A rapid analysis of fresh grass silage samples for dry matter (DM) and crude protein (CP) content would provide basic, rapid information what would permit decision to be made regarding the need to supplement the diet. The aim of the present study was to determine dry matter (DM) and crude protein (CP) content in fresh grass silage samples by NIR spectroscopy. Crude protein content can be expressed as g per kg dry matter (g kg-1 DM) or as per cent of fresh weight (% FW). Near-infrared reflectance spectra were recorded for 103 fresh grass silage samples. Laboratory analysis of DM and CP were determined for these samples. MLR, PCR and PLS techniques were used for data modelling to determine the optimum models for predicting each of the chemical constituents. It was concluded that the PLS method was superior to the PCR and MLR methods for DM and CP prediction in fresh grass silage samples, while MLR showed a promising possibility to determine the CP content using only two spectral values measured at two “characteristic”wavelengths.
Authors:Ekambaram Sanmuga Priya, Perumal Senthamil Selvan, and Krishnamoorthy Marudhupandian
Various chromatographic techniques have been designed to estimate soy isoflavones in finished products as well from Glycine max (L.) Merrill. As an attempt to develop a simple, accurate, and validated method for routine analysis of daidzein and genistein, the major isoflavones as an established standardization technique, a high-performance thin-layer chromatographic (HPTLC) method has been developed. A comparative analysis of individual isoflavone (daidzein and genistein) contents in different varieties of G. max CO-2, CO (soy) 3, and local white was also carried out. Extraction efficiency of the targeted isoflavone from the seed matrix with organic solvents using ultrasonication technique was studied. The methanolic extract of the soybean seeds was taken for method development and validation procedures by HPTLC in which separation was achieved on silica gel 60 F254 HPTLC plates using chloroform-methanol (20:1 v/v) as the mobile phase. The individual isoflavones and protein contents were estimated in three different varieties of soybean in which CO-2 variety has shown the highest content.
Authors:B. Constantinescu, E. Ivanov, D. Plostinaru, A. Popa-Nemoiu, and G. Pascovici
The reaction14N(p, n)14O(71 s) is used, with a proton beam of 14 MeV energy and 100 nA intensity. The14O activity is detected by means of its characteristic 2.312 MeV gamma-ray (9.4%), with a NaI(T1) detector. The intensity ratio of gamma-rays to that of the incident particles for the sample, related to a similar ratio in adequate standards determines the nitrogen content in the sample. The measurement is completely automated. If we protect the embryo region during irradiation, the future germination of the analyzed seeds will be normal. Good correlation has been obtained between the results of the present method and those of the chemical Kjeldahl method.
Authors:Adnan Eser, Hajnalka Kató, Laura Kempf, and Márton Jolánkai
Water availability is one of the major physiological factors influencing plant growth and development. An assessment study has been done at the Szent István University, Gödöllő to evaluate and identify the water footprint of protein yield of field crop species. Twelve field crop species (Sugar beet Beta vulgaris, spring and winter barley Hordeum vulgare, winter wheat Triticum aestivum, maize Zea mays, sunflower Helianthus annuus, peas Pisum sativum, potato Solanum tuberosum, alfalfa Medicago sativa, oilseed rape Brassica napus, rye Secale cereale and oats Avena sativa) were involved in the study. Evapotranspiration patterns of the crops studied have been identified by the regular agroclimatology methodology and physiologically reliable protein ranges within crop yields were evaluated.
The results obtained suggest, that water footprint of cereals proved to be the lowest, however maize values were highly affected by the high variability of protein yield. Oilseed crops had considerably high protein yield with medium water efficiency. Alfalfa, potato and sugar beet water footprints were in accordance with their evapotranspiration patterns.
Protein based water footprint assessment seems to be more applicable in crop species evaluations than that of yield based methodologies.
Authors:David Tjandra Nugraha and Fransiscus Sabatino Bata
proteincontent of this bean is high (20–28%) and one of the best source for iron mineral (155 mg/100 g bean) ( Kay, 1979 ). The amount of protein in this bean does not differ too much with other high-protein beans such as soybean. Lablab bean has a very
Authors:Gustavo Guadagnucci Fontanari, José Manuel Martins, Marcelo Kobelnik, Iêda Aparecida Pastre, José Alfredo Gomes Arêas, José Paschoal Batistuti, and Fernando Luis Fertonani
extreme pH values, Na 2 SO 3 was added [ 17 ].
Obtaining of protein isolates (PIs)
Table 2 shows average values of the extraction yield and proteincontent for PIs obtained from LSF. This table shows that
Authors:Aidin Pahlavan, Mohammad Hassan Kamani, Amir Hossein Elhamirad, Zahra Sheikholeslami, Mohammad Armin, and Hanieh Amani
affect 1,000-grain weight value, Zeleny value, proteincontent, wet and dry gluten, gluten index as well as the elasticity and hardness of dough. However, no marked change was observed in the residue value and moisture content. The Zareh variety showed
Authors:Ghalib Al-Saidi, Mohammad Shafiur Rahman, Ahmed Al-Alawi, and Nejib Guizani
gelatin obtained, for all acetic acid concentrations used.
The protein contents of PG and BG were 89.0 and 86.7 g/100 g sample, while proteincontent for shaari fish varied from 64.7 to 89.0 g/100 g sample depending on the conditions of extraction