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The purpose of the study was to determine the influence of temperature and rainfall on selected quality traits and parameters of the yield structure in the period from kernel filling to maturity. The research material comprised 30 strains and variations of winter wheat collected by the staff of the Plant Breeding and Acclimatization Institute. The following traits were marked: resistance to pre-harvest sprouting, falling number and sedimentation value, protein content, 1000-kernel weight, the number and weight of kernels in an ear as well as the number of days from heading to full maturity.The least stable trait over the annual periods proved to be the resistance to pre-harvest sprouting and the falling number. It was observed that dry and hot summers tended to shorten the period between kernel filling and maturity and also to increase falling number and sedimentation value. Also, a very high correlation was observed between the number of days without rain and resistance to pre-harvest sprouting. In the years with a high level of rain and a balanced distribution of rainfall, there were significant negative correlations between the number of kernels per ear, on the one hand, and protein content and sedimentation value on the other, and also between the sedimentation value and the kernel weight per ear. In the years with the least number of rainfalls, such correlations were not observed.

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The protein content, solubility and functional properties of a total protein concentrate prepared from the seeds of Ailanthus excelsa Roxb. were determined. The effects of pH and/or NaCl concentration on some of these functional properties were also investigated. The protein content of the seed protein concentrate was found to be 65.88%. The minimal protein solubility was observed at pH 4 and the maximum was at pH 12. Water- and oil-holding capacities of the seed protein concentrate were 2.77 g g −1 and 5.79 g g −1 , respectively. The emulsifying activity and emulsion stability, as well as foaming capacity and foam stability, were greatly affected by pH levels and salt concentrations. Lower values were observed at slightly acidic pH (pH 4.0) and high salt concentration. Total protein concentrate was highly viscous which depends on concentration and pH levels. The lowest gelation concentration of seed protein concentrate was found to be 14% and 8% when the proteins were dissolved in distilled water and 0.5 M or 1 M NaCl solution, respectively.

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Comparative study of composition and technological quality of amaranth

I. Gross chemical composition, amino acid and mineral content

Acta Alimentaria
Authors: S. Tömösközi, I. Baracskai, R. Schönlechner, E. Berghofer, and R. Läsztity

Eight groups of amaranth grain samples, belonging to the species Amaranthus cruentus and A. hypochondriacus , grown in Austria and Hungary were studied. Gross chemical composition, amino acid content and mineral composition of the whole grain were determined. The effect of heat treatment on amino acid content was also investigated. The range of concentration of main constituents of samples studied corresponded to the average data reported by other researchers. However, the relatively big difference between lowest (14.23%) and highest (17.40%) protein content suggests that genetic potential for increasing the protein content may be realized in breeding. Amino acid composition profile is generally closer to Leguminosae than to cereal grains except for sulphur containing amino acids being present in higher amount in amaranth than in legumes. The concentrations of minerals in seeds varied in a relatively wide range, and the micro-components, like Fe, Cu, Zn, were present in higher amount in amaranth seeds compared to the average values found in wheat. It was confirmed that heat treatment of amaranth grain (e.g. popping) might reduce the available lysine content. Contradictory data published in the literature may be explained by differences in initial sugar and moisture content of grain, which influence the rate of potential Maillard-reaction.

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An experiment was set up at five locations in Hungary in 2005, in a randomised block design with four replications. At each location 24 hybrids were tested from each of four maturity groups (FAO 200, FAO 300, FAO 400, FAO 500). Evaluations were made of the yield average (t/ha) and the yield components of the sample ears: ear length, number of kernel rows, thousand-kernel mass and kernel/cob ratio. This was followed by chemical analysis to determine the protein, oil and starch contents of the kernels. The chemical quality parameters were recorded for almost 100 hybrids, and the correlations of the protein, oil and starch contents with yield and yield components were analysed. It was found that in all the maturity groups the yield was closely correlated with the thousand-kernel mass (0.72). In each maturity group the highest yield averages were associated with the greatest average starch contents, except for the FAO 500 group in the Szarvas location, where the development of secondary ears contributed to the achievement of the highest yield average. A very close correlation was found between the starch content and the thousand kernel mass (0.91). The variety caused greater differences in protein content than the location. This was also true for the oil content in the FAO 200 and FAO 400 groups, but only in the FAO 400 group in the case of starch content. More starch was incorporated at wetter locations, where the protein content of the samples was lower.

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Increasing the protein and antioxidant content of food products is a constant challenge amongst researchers. Dried pasta products are popular amongst all groups of society. The most important factor in pasta processing is the quality of the flour. Millet (Panicum miliaceum) flour has high nutritional value, enriching it with cricket (Gryllus bimaculatus) flour is good choice to increase the quality of protein composition and antioxidant properties of products. Flour mixtures of millet and insect flours (5% and 10%) were analysed after mixing and pasta processing. Addition of wheat gluten improved both texture and nutrition value of pasta products. Total polyphenol content, antioxidant capacity, total protein content, free and total amino acid composition were studied. Quality analysis of dried pasta products were carried out according to Hungarian standards. Data was analysed with Kruskal-Wallis test, Dunn's pair-wise post hoc test was used with Bonferroni correction. The correlation was determined by Spearman's rank. Addition of cricket flour modified the pH, acid value, moisture content, and colour of the samples, these changes lasted during storage. Enrichment could increase the total phenol content significantly even at the low level of 10%. Heat treatment during pasta processing had negative effect on the antioxidant capacity except at higher cricket flour contents. Cricket flour's high protein content proportionately increased millet flour's, thus pasta products'. Dried pasta products passed all quality norms. Enrichment of millet flour with cricket flour is favourable from both nutritional and quality aspects.

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Abstract  

Determination of protein content in food materials is usually done by analyzing the nitrogen amount by wet chemical Kjeldahl method. An improved accuracy accompanied by smaller analyzing intervals can be achieved using nondestructive neutron activation. Analyses have been performed using 14 MeV neutrons to determine the content of N and P in single wheat corns. Irradiation parameters have been optimized to prevent serious radiation damage in the grains. About 200 single corns have been investigated with total net weights ranging from 30 to 70 mg. The tested arrangement allows determination of nitrogen amount in a single corn down to 0.3 mg with an accuracy of better than 4%. Mean nitrogen concentrations in the range from 9 to 19% per corn have been detected.

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The chemical composition and thermal behaviour of crab, shrimp and lobster shells were studied. The lobster cephalothorax and its main parts also constitute important sources of both polymers. Their chitin and protein content are 20 and 40 %, respectively (dry base) while in these cases the proteins are less associated to the matrix than in the carapace. The chitin level in the chitinous concentrates isolated from different sources is over 80 % in all cases but the polymer characteristics change in dependence on the raw material.

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Durum wheat landraces are still cultivated to take advantage of their excellent grain and straw quality, adaptation to abiotic stresses, and extremely wide variety of uses. The safeguarding and rehabilitation of genetic inheritance requires genetic characterization and evaluation. In this study, forty durum wheat landraces originating from Mediterranean countries were evaluated according to agro-morphological and technological properties. We show that the germplasm was highly variable. The mean yellow pigment and protein content was higher in landraces (15.58%; 7.32 ppm) than in the Moroccan cultivars used as controls (14.6%; 5.48 ppm). In addition, principal component analysis identified five groups showing variable agronomic and qualitative characteristics that might be useful in the rational design of breeding programs.

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Winter wheat (Triticum aestivum L.) yield samples taken from a consecutive series of crop years representing drought, normal and moist conditions at the Nagygombos experimental site of the Szent István University have been evaluated. The impact of N topdressing and crop year conditions on the performance of protein and wet gluten content were studied.The results suggest that ascending levels of N topdressing, and increased number of applications had a beneficial effect on the protein content, as well as on wet gluten values. Crop year had a significant effect on quality manifestation. The drier the crop year, the better the recorded quality performance. The magnitude of changes was bigger in case of gluten than in that of protein values. There were minor differences between the two varieties examined, especially in their response patterns to nitrogen supply. Dough formation depends mainly on the gliadin/ glutenin ratio, but there is less information on the agronomic and climatic impacts that may cause alterations in that.

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In a long-term experiment on continuous maize set up by Béla Győrffy in 1959, changes in biotic and abiotic environmental factors were studied over time. The long-term effects and stability of the cropping systems, the year effects and the genotype × environment interactions were analysed. The original aim of the experiment was to determine whether the NPK nutrients in farmyard manure could be replaced partially or entirely by inorganic NPK fertiliser. In the present experiment the effect of farmyard manure, mineral fertiliser and the year effect on yield and yield stability were studied for four years (2005–2008). Various levels of farmyard manure and mineral fertiliser induced significant changes in the yield, harvest index, thousand-kernel mass, grain number per ear and grain protein content.

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