Biorefining Protein from UK Grasslands - Can We Combine Novel Protein with Surplus Bread Crusts to Sustainably Feed Healthier Food to More People?

英国的草原农业覆盖了已利用农业区的72%(1260万公顷)，分别养活了970万头牛和3400万只羊1。再加上到2040年实现零碳的努力，从畜牧业和植物蛋白进口(如大豆和其他豆类)转向适合人类消费的替代岸上种植的植物蛋白，可能会为英国农民提供更长期的环境效益经济保障。英国国内存在现有农业水平上生产植物蛋白的机会。大约70%的英国商业牧草(Loillium/Festuca spp.&lt；10%粗蛋白)和三叶草(Trifolium spp.&lt；20%粗蛋白)品种已经在阿伯里斯特威斯大学培育出来。以前的研究已经证明，在压榨草和/或三叶草后，这种蛋白质很容易作为液体流提取，而剩余的纤维可以用作动物饲料，显示出与原始草的营养等价性(羊肉试验-STAR项目AU，牛肉试验-奥胡斯大学2，3)。此外，草含有可溶性果聚糖(-2，1和-2，6-果糖多糖，20%DM)，是一种有效的前生物制剂(AU；英国和欧洲专利，美国专利申请)。红三叶汁，也含有次生代谢物(植物雌激素和皮尼醇等)。具有已知的营养/功能性质。这两种多年生作物都能固碳，而三叶草还具有固氮的额外优势，从而减少了化肥投入。一种将这种富含蛋白质的材料转化为富含蛋白质的食品配料和/或产品的方法是通过联合发酵过程(例如，丹贝生产)。然而，使用的大多数本地细菌是致病的(即肺炎克雷伯氏菌)4，因此，研究与Gras状态的生物进行替代共培养，不仅具有营养价值，还具有监管和营销效益。素食和弹性饮食是一种不断增长的长期趋势，后者每年可增长9%。在这些有洞察力的消费者的未来需求中，包括对非转基因、合乎道德的植物蛋白的强烈偏好，以及由可追溯的供应链证书支持的、确保对环境和社会负责的农场到叉子制造的支持。Samworth Brothers Ltd(SBL)是英国领先的三明治供应商，其制造业务每周生产30-50吨多余的面包皮，这些面包皮的处置路线是作为动物饲料。使用英国种植的农作物中的植物蛋白来保持这种面包在人类食物链中的地位，是桑沃斯兄弟公司未来的抱负。富含蛋白质的新配料的开发对食品工业涉及许多挑战，因为产品必须具有高营养价值(氨基酸分布和消化率)、无过敏性、适当的技术特性(如溶解性、起泡性等)、可接受的味道和口感(收敛)。通过共发酵可以降解抗营养因子，发展蛋白质结构，并产生其他代谢物(维生素B12)和风味(鲜味)；因此，控制底物、生物体和过程可以帮助开发一种新的生物精炼工艺来生产高质量的植物蛋白食品(S)。本研究要检验的假设是：从饲草/三叶草中提取的富含蛋白质的果汁与剩余的面包壳可以通过混合微生物群进行生物转化，从草原中生产出安全、可持续的新型人类食品成分(图1)。本研究的目标是：1)优化提取、浓缩和纯化富含蛋白质和营养物质(果糖、植物雌激素和皮尼醇)的草本植物/三叶草果汁。2)开发一种固态乳杆菌生物精制富蛋白果汁的工艺。弗氏丙酸杆菌(GRAS)和根霉发酵，利用多余的面包皮作为支架(实验室和中试植物S

British grassland farming covers 72% (12.6 million ha) of the utilised agricultural area, supporting 9.7 and 34 million cattle and sheep respectively1. Coupled with the drive towards zero-carbon 2040, diversification away from livestock production and plant-protein imports (e.g. Soya and other pulses) to alternative on-shore grown plant-protein fit for human consumption may provide longer-term environmentally beneficial economic security for UK farmers.The opportunity for plant-protein production on an existing agricultural level exists within the UK. Approximately 70% of the UK's commercial forage grass (Loillium/Festuca spp. <10% crude protein) and clover (Trifolium spp. <20% crude protein) varieties have been bred at Aberystwyth University (AU). Previous research has demonstrated that this protein is readily extractable as a liquid stream following pressing of grass and/or clover, while the remaining fibre can be used as an animal feed showing nutritional equivalence with the original grass (lamb trials-STARS project AU, beef trials-Aarhus University2,3). Furthermore, grass contains soluble fructan (-2,1 and -2,6-fructosylpolysaccharides, 20% DM), an effective pre-biotic (AU; UK & European Patent, US patent filed). Red clover juice, also contains secondary metabolites (phytoestrogens and pinitol etc.) with known nutraceutical/functional properties. Both of these perennial crops sequester carbon, while clovers have the added advantage of nitrogen fixation, thereby reducing fertiliser inputs. A method to convert this protein-rich material into a protein-rich food ingredient and/or product is through co-fermentation processes (e.g. tempeh production). However, most of the native bacteria used are pathogenic (i.e. Klebsiella pneumoniae)4, thus the investigation of alternative co-culture with a GRAS status organism, will not only be of nutritional value, but also regulatory and marketing benefit.Vegetarian and flexitarian diets are a growing, long-term trend, with the latter achieving 9% growth per annum. Among the future needs of these discerning consumers are a strong preference for non-GM, ethically sourced plant-protein supported by traceable supply chain credentials ensuring environmental and socially responsible farm to fork manufacture. Samworth Brothers Ltd (SBL) are a leading UK sandwich provider; producing 30-50 tonnes per week of excess bread crusts from their manufacturing operations whose disposal route is as animal feed. Using plant-protein from UK grown crops to keep this bread in the human food chain is a future aspiration of Samworth Brothers. The development of new protein-rich ingredients involves many challenges to the food industry as the product must have a high nutritional value (amino acid profile and digestibility), no allergenicity, adequate technological properties (e.g. solubility, foamability etc.), acceptable flavour and mouthfeel (astringency). Through co-fermentation anti-nutritional factors can be degraded, protein structures are developed, and other metabolites (vit B12) and flavours (umami) are produced; thus, controlling the substrate, organism and process could help develop a novel biorefining process producing high quality vegetable protein-rich food product(s).The hypothesis to be tested in this studentship is: Protein-rich juice extracted from forage grass/clover and combined with surplus bread crusts can undergo bioconversion by mixed microbial consortia producing a safe, sustainable, novel human food ingredient from grasslands (fig1).The objectives of this studentship are: 1) Optimisation of extraction, concentration and purification of grass/clover juice rich in protein and nutraceuticals (fructans, phytoeostrogens and pinitol).2) Development of a biorefining process for protein-rich juice through solid-state Lactobacillus spp., Propionibacterium freundenreichii (GRAS) and Rhizopus spp fermentation, using excess bread crusts as a scaffold (laboratory and pilot plant s