How to use the world's scarce selenium resources efficiently to increase the selenium concentration in food

The world's rare selenium resources need to be managed carefully. Selenium is extracted as a by-product of copper mining and there are no deposits that can be mined for selenium alone. Selenium has unique properties as a semi-conductor, making it of special value to industry, but it is also an essential nutrient for humans and animals and may promote plant growth and quality. Selenium deficiency is regarded as a major health problem for 0.5 to 1 billion people worldwide, while an even larger number may consume less selenium than required for optimal protection against cancer, cardiovascular diseases and severe infectious diseases including HIV disease. Efficient recycling of selenium is difficult. Selenium is added in some commercial fertilizers, but only a small proportion is taken up by plants and much of the remainder is lost for future utilization. Large biofortification programmes with selenium added to commercial fertilizers may therefore be a fortification method that is too wasteful to be applied to large areas of our planet. Direct addition of selenium compounds to food (process fortification) can be undertaken by the food industry. If selenomethionine is added directly to food, however, oxidation due to heat processing needs to be avoided. New ways to biofortify food products are needed, and it is generally observed that there is less wastage if selenium is added late in the production chain rather than early. On these bases we have proposed adding selenium-enriched, sprouted cereal grain during food processing as an efficient way to introduce this nutrient into deficient diets. Selenium is a non-renewable resource. There is now an enormous wastage of selenium associated with large-scale mining and industrial processing. We recommend that this must be changed and that much of the selenium that is extracted should be stockpiled for use as a nutrient by future generations

Selenium status in dairy cows and feed samples in Estonia

Introduction: Knowledge about selenium content in Estonian food chain is limited as no systematic selenium study is ever done in Estonia. Aim of our study was to evaluate selenium status in dairy cows and feed samples. Materials and methods: Altogether, 17 commercial dairy herds from 13 Estonian districts were studied. Blood samples from ten cows in each farm were collected. From each farm grain sample was taken. Information about feeding of selenium containing feed supplements and grain origin was asked. Selenium content in grain and glutathione peroxidase (GPx) activity in haemolysed whole blood was analysed. Results and discussion: Mean GPx activity in cows was 92-1204 ŠÌKat/l. Dividing cows into selenium-deficient (GPx¡Ü472 ŠÌkat/L) and non-deficient (GPx>472 ŠÌkat/L) group, it came evident that 66% cows were seleniumdeficient and only 34% of the cows belonged to the non-deficient group. Locally grown grain was used in 10 farms. Selenium content in local grain was below 0.02 mg/kg dw in 6 samples and 0.04-0.12 mg/kg dw in 4 samples. Selenium content in commercial grain was 0.37-0.90 mg/kg dw (n=7). Selenium containing mineral feed was used in 9 farms. Results of our study confirm the presence of selenium-deficiency in plant-animal chain in Estonia. Selenium status in Estonian food chain must be monitored to decide on the most effective way of selenium supplementation.vokMyynti MTT Tietopalvelut 31600 Jokioine