Die Nahrung最新文献

Serum levels, urinary excretion and plasma clearance of urea, uric acid and creatinine were studied in adult (230 g) and growing (75 g) rats under the influence of nialamide (an IMAO) administered in daily doses of 20 mg/100 g diet during 15 or 30 days in adults and 10 mg/100 g diet during 15 days in growing rats. A pair feeding design was used in both ages. Serum levels of urea rose in adult rats fed nialamide for 30 days while urinary excretion decreased. No change in serum levels were noted in growing rats although urinary excretion showed a net increase. Serum uric acid levels were increased in adult female rats given nialamide for 30 days, while urinary excretion fell in both sexes. Growing rats showed a drop in urinary excretion of uric acid. Serum creatinine levels were unchanged in adult and growing rats after treatment with nialamide, although a marked increase was recorded in urinary excretion in both groups.

The response of adult rats to wheat flour protein fortified by addition of lysine was studied by utilizing the relative protein value (RPV) compared to non-fortified wheat flour. Lactalbumin was used as a standard protein. Fortification of wheat flour by 0.3% lysine resulted in better growth of rats when fed at 6% protein level. However, no significant difference was observed in the growth of rats fed non-fortified or fortified wheat flour at 4% or 2% protein level. The relative nutritive value (RNV) of supplemented wheat flour protein is higher than that of the non-supplemented when change in body weight or change in body water are used as response parameters. When the dietary protein is provided at maintenance or below maintenance levels, lysine is not limiting. Therefore, supplementation of wheat flour protein with lysine did not result in any better growth response. When protein is provided at levels above maintenance requirements lysine is limiting and better growth was achieved by lysine supplementation to wheat flour protein.

Cowpeas have been a major source of protein, especially in developing nations. Despite of the fact that aflatoxin contaminations have been found to be mainly common in substrates such as carbohydrates, detection of the toxins in raw cowpeas has also been reported [7]. It is therefore important and necessary to investigate fate of the aflatoxin when raw cowpeas are processed into various products. In Nigeria, cowpea seeds are usually consumed after boiling to softness and mixed with ingredients such as pepper, salt and palm-oil to form a porridge. Other processing methods involve wet milling the cowpea seeds and either steaming in aluminium cups or in leaves to form 'moinmoin', or frying in oil to form 'akara' balls. In this work therefore, the fate of the aflatoxins as a result of the processing of artificially contaminated cowpeas was investigated.

The addition of calcium ions to iron-gossypol complex in phosphate solution has been reported to effect the removal of the soluble ferrous-gossypol complex from solution. These workers then postulated that the formation of insoluble ferrous-gossypol by calcium may explain the biological synergistic effect of calcium with iron in the inactivation of gossypol. Earlier studies by Skutches et al. indicated reduced haemoglobin, haematocrit and total serum protein in pigs fed 0.06% free gossypol diet. While other attempts at gossypol detoxification using divalent ions have been, mainly, in the form of calcium hydroxide and/or ferrous sulphate, this paper describes the dose-response relationships between dietary oyster shell (a much cheaper source of calcium than Ca(OH)2) and some serum constituents and erythrocyte indices in the chicken fed gossypol-containing cottonseed cake (CSC) diets.

The basis of the requirement for nutrio-toxicological model investigations is the result of many years of international experience. They are, however, limited for pragmatic reasons to standardized one-dimensional test conditions and can only be partially compared with the variable exposure conditions of man. Therefore, we have tried to review the practical significance of factors influencing nutrio-toxic effects. It has been shown that due to physiological and genetic differences, different lifestyle, biogeochemical and nutritional factors, additional occupational exposure as well as spontaneous diseases individual sensitivity shows a great variation range in man and laboratory animals. The multiple exposure which is common practice makes it difficult to provide proven evidence. The safety factor used for the extrapolation of results obtained in animal experiments as compared with man is a suitable pragmatic safety measure, but in the case of 1:100 as to the order of magnitude it is not always in accordance with the range of response to xenobiotics in a human population. This fact raises the necessity of searching for so-called "risk-groups" in the population. Additionally, the possible acceleration of spontaneous diseases by exposure to xenobiotics has to be taken into consideration.

Bread was made from dough previously inoculated with spores of three Bacillus cereus strains at different inoculation levels. Counts of survivors and bread staling were determined in bread during storage at 25 degrees C. The total aerobic bacteria, sporeformer and B. cereus counts in seven different wheat flours were 3.0 x 10(6) to 9.1 x 10(7), 3.2 x 10(5) to 1.5 x 10(6) and 50-100 colony forming units (CFU/g). About one in a thousand bacteria were found to survive baking. On the other hand, no multiplication took place, however, until the bread had been stored for more than 3 days. Also, survival and multiplication of B. cereus spores was shown to depend on the kind of strains and type of bread. The addition of B. cereus strains to the dough gave bread with higher freshness than the control sample. This was quite noticeable in inoculated pan bread during storage. It is possible to conclude from the results that B. cereus survive the baking process particularly if original contamination is high. Also increasing the freshness of the bread does not necessarily mean better ingredient and processing conditions.

Six wheat seeds varieties taken for experiments showed some differences in crude protein content ranging from 10.4-12.8%. A procedure for protein fractionation by the successive elimination of albumins, globulins and gliadins from the wheat varieties studied was elaborated. In the obtained protein fractions endogenous amylolytic and inhibitory activities tested against bovine pancreas trypsin and alpha-amylases of mammalian and insect origin were determined. The determined biological activities differ considerable among wheat varieties studied and were mainly located in albumins and gliadins while only a small amount were detected in globulins. Extractable proteins were relatively thermostabile and powerful inhibitors of the alpha-amylases examined. As the influence of environmental conditions was the same for all wheat varieties studied the observed differences in biological activities should be rather attributed to the genetic differences.

The biological value of proteins as well as their importance for the technological quality of wheat flours have been extensively researched. Apart from the other factors, gluten content, structure and functional characteristics are responsible for the flour's technological properties. Functional properties of gluten complex and thus also rheological properties of flour are influenced by the specificity and intensity of interactions among individual protein fractions and likewise of protein interactions with other flour components. Rheological properties of flour and quality parameters of bread are changed to a greater or lesser extent, among other, by addition of free amino acids. The purpose of this work was to explore the relationship between certain essential amino acids of wheat flour and the parameters of flour rheology and bread baking quality.