Evaluation of a hybrid microwave process to replace malt kilning: feasibility and impacts on malt quality

麦芽窑是一种传统的热风干燥过程，是能源密集型的，占麦芽酿造过程中一次能源使用量的78%左右，仅在英国，这一部门每年就会产生30万吨二氧化碳。该行业需要找到节能的替代方案，以减少其碳足迹。该项目将把世界上最大的麦芽公司Boortmalt与专门从事麦芽和酿造科学（Cook）和微波工艺工程（Dodds）的学术合作伙伴聚集在一起。Boortmalt是世界上最大的麦芽公司，在全球拥有27家麦芽工厂，可持续性和创新是其战略支柱。这些合作伙伴已经在一个布尔马特资助的项目上进行合作，利用微波/热风混合干燥技术开发新型烤麦芽和休闲食品。这种流化床技术正在利用诺丁汉微波过程工程团队的专业知识进行商业化开发。它在干燥过程中提供了对单个颗粒温度梯度的独特控制水平。目前的项目针对的是酶的生存不重要的应用，目的是生产新的产品，而不是匹配现有的规格。博士研究生将评估将该技术应用于淡麦芽生产的可行性，淡麦芽在全球酿酒中用作基础麦芽，全球年产量为2400万吨。这是一个要求更高的应用，因为空气和微波干燥的组合必须调整，以便在连续操作中实现实际的吞吐量，同时确保关键的酿造酶（如淀粉酶，-葡聚糖酶）不会热变性。此外，其他关键规格，如颜色和味道，必须与传统的烧制产品密切匹配。该项目将评估这种方法的环境影响、技术和经济可行性，密切合作，并将拟议的技术与目前的技术水平进行比较。

Malt kilning is a traditional hot-air drying process that is energy intensive, accounting for around 78% of primary energy usage in the malting process, a sector which is responsible for 300,000 t of CO2 annually in the UK alone. The sector needs to find energy efficient alternatives to this process, to reduce its carbon footprint. This project will bring together Boortmalt, the world's largest malting company, with academic partners specialising in malting and brewing science (Cook) and microwave process engineering (Dodds). Boortmalt is the largest malting company in the world with 27 malting plants across the globe and sustainability and innovation are two of its strategic pillars. The partners are already collaborating on a Boortmalt funded project to develop novel roasted malts and snack foods using hybrid microwave/ hot-air drying technology. This fluidised bed technology is being developed commercially with the expertise of the Microwave Process Engineering Team at Nottingham. It offers unique levels of control over temperature gradients within individual particles during drying. The present project targets applications where the survival of enzymes is of no importance and the aim is to produce novel products rather than to match existing specifications. The PhD studentship will evaluate the feasibility of applying the technology to the production of pale malts, which are used as base malts in brewing worldwide, with a global annual production of 24 million tonnes. This is a much more demanding application because the combination of air and microwave drying must be tuned in order to achieve a realistic throughput in continuous operation, whilst ensuring that key brewing enzymes (e.g. amylases, -glucanases) are not thermally denatured. Furthermore, other key specifications such as colour and flavour must be closely matched to conventional kilned products. The project will evaluate both the environmental impact, technical and economic feasibility of this approach working closely and benchmarking the proposed technology against the current state of the art.