SBIR Phase I: Production and Separation of Galacto-Oligosaccharides from Lactose for Prebiotic Food Applications

这个小企业创新研究（SBIR）第一阶段项目将开发一种新的固定化酶工艺，从乳清乳糖生产用于益生菌食品应用的低聚半乳糖（GOS）。提出的GOS生产工艺包括两个固定化酶反应器和通过纳滤和吸附色谱法分离产物。将使用具有不同GOS形成特征的两种不同α-半乳糖苷酶来优化乳糖的GOS生产和产率。来自第二反应器的产物流将被送至纳滤（NF）分离单元，其中GOS、乳糖、半乳糖和葡萄糖可被分离以产生具有较高GOS组成的产物。进一步开发活性炭吸附和离子交换液相色谱法的工艺，以进一步纯化GOS。该项目的商业应用将在新兴的益生菌和营养食品市场，供动物和人类使用。据估计，这个市场每年超过20亿美元。目前，GOS在食品中的使用受到高生产成本的限制。这些成本主要归因于高酶成本和低寡糖产率（小于30%w/w）。预计该技术将通过提高反应器生产率和酶寿命来降低至少50%的生产成本。此外，使用廉价乳清前体产品（当前价格范围：$0.12-$0.40每磅）到增值GOS产品（当前价格：$4-$5每磅）的能力将对乳制品工业非常有益。

This Small Business Innovation Research (SBIR) Phase I project will develop a novel immobilized enzyme process to produce galactooligosaccharides (GOS) from whey lactose for probiotic food applications. The proposed GOS production process involves two immobilized enzyme reactors and product separation by nanofiltration and adsorption chromatography. Two different alpha-galactosidase enzymes with different GOS formation characteristics will be used to optimize GOS production and yield from lactose. The product stream from the second reactor will be sent to a nanofiltration (NF) separation unit, where GOS, lactose, galactose, and glucose could be separated to yield a product with a higher GOS composition. The process for adsorption with activated carbon and ion exchange liquid chromatography will be developed to further purify GOS. The commercial application of this project will be in the emerging probiotic and neutraceutical food market for use by both animals and humans. This market is estimated to be in excess of 2 billion dollars per year. The present use of GOS in foods is limited by the high production costs. These costs are attributed mainly to the high enzyme cost and low oligosaccharide yields (less than 30% w/w). The proposed technology is expected to reduce production costs by at least 50% due by improving reactor productivity and enzyme life. Further, the ability to use cheap whey precursor products (current price range : $ 0.12 - $ 0.40 per lb) to value added GOS product (curent price : $ 4 - $ 5 per lb) will be of great benefit to the diary industry.