13TSB_N4L2FS: Development of silage inoculants to improve mineral composition of animal products

消费者对他们吃的食物越来越着迷，随之而来的是对更健康、更有营养的功能食品的需求增加。该项目将开发新的动物产品，以增加对消费者的生物可利用营养素的供应，减少对膳食补充剂的依赖。硒是人体必需的二十多种硒蛋白的组成部分，这些硒蛋白在生殖、甲状腺激素代谢、DNA合成和保护免受氧化损伤等方面发挥着关键作用。生物可利用硒的摄入量不足在生活在缺硒地区的人、素食主义者和纯素食主义者中很常见。硒缺乏也见于正在进行肾脏透析的患者、艾滋病毒携带者和老年人，因为通过透析去除了硒，腹泻和吸收不良增加了损失。硒在多种矿物质补充剂中以无机亚硒酸钠或亚硒酸钠的形式存在。然而，人体只吸收50%的硒以亚硒酸盐或亚硒酸盐的形式存在，相比之下，超过90%的硒以有机硒蛋氨酸和硒半胱氨酸的形式存在(IFMNB，2000)。人类饮食中有机硒的良好来源是来自动物产品，如乳制品和反刍动物肉类。然而，由于放牧期间土壤硒状况的性质以及青贮饲料中典型的低水平矿物质含量，成分的变异性很大。2005年的一份报告估计，典型的英国青贮饲料中的硒含量不到最佳牲畜营养所需硒的21%(FWL，2005)。因此，用无机硒形式的矿物质来补充反刍动物是很常见的。与人类一样，无机形式的生物利用度明显低于有机硒，需要更高的剂量。此外，将无机硒转化为牛奶和肌肉硒蛋白的效率很低，导致供人类食用的动物产品中的硒含量较低。因此，能够使用将硒作为有机形式加入的青贮料接种剂，自然会增加动物有效硒的供应，并使产品富含高度生物可利用的营养物质。因此，该项目将通过提高动物产品中的有机硒来开发一种新的营养输送方法。它还将开发一种新的更健康的食品，这种食品将允许更多地吸收有机硒，而不需要通过无机矿物质片剂进行饮食补充。此外，通过更强的抗氧化能力增加动物产品中的硒将延长产品的保质期，减少浪费。

Consumers have an increasing fascination with the food they eat with a subsequent increase in demand for healthier, more nutritional functional food. This project will develop novel animal products which will increase the supply of bioavailable nutrients to the consumer reducing the reliance on dietary supplements. Se is essential for humans as a constituent of more than two dozen seleno-proteins which play critical roles in reproduction, thyroid hormone metabolism, DNA synthesis and protection from oxidative damage. Inadequate intakes of bioavailable Se are common in people living in Se-deficient regions, vegetarians and vegans. Se deficiency is also seen in patients' under-going kidney dialysis, people living with HIV and the elderly due to removal of Se through dialysis, increased loss through diarrhoea and malabsorption. Se is available in multimineral supplements as inorganic sodium selenate or sodium selenite. However, the human body absorbs only 50 % of Se as either selenate or selenite compared to over 90 % of Se in the form of organic selenomethionine and selenocysteine (IFMNB, 2000). Good sources of organic Se in the human diet are from animal products such as dairy and ruminant meat. However variability in composition is large due to the nature of the Se status of the soil during grazing and also the low levels of minerals contained typically in ensiled forage. A 2005 report estimated that typical UK silage contained less than 21 % of the Se requirement for optimum livestock nutrition (FWL, 2005). It is therefore common to supplement ruminants with minerals in the form of inorganic Se. As with humans the bioavailability of the inorganic form is significantly less than organic Se requiring a higher dose. In addition the conversion of inorganic Se into milk and muscle seleno-protein is inefficient resulting in lower levels in animal products for human consumption. Therefore the ability to use a silage inoculant which incorporates Se as an organic form will naturally increase the supply of available Se to animals and enrich products with a highly bioavailable form of the nutrient. As such the project will develop a novel method of nutrient delivery by enhancing organic Se in animal products. It will also develop a novel healthier food which will allow greater absorption of organic Se without the need for dietary supplementation through inorganic mineral tablets. In addition an increase in Se in animal products through greater antioxidant capacity will improve product shelf life and reduce waste.