Malt Roasting: Development Of Novel Flavour Extracts Through Microwave Processing

酿造行业需要“干净的标签”调味品来开发新产品，并提高低度和非酒精啤酒的适口性。用液态二氧化碳提取的酒花香气馏分在这个市场上取得了商业上的成功。有人建议，类似的产品，基于对烘焙谷物产品中不同口味的分馏，也可以被证明同样成功。这种方法的优点包括可持续和高效的产品使用(下游添加)和通过分馏创造新风味的能力。作为商业化的先决条件，有必要最大化烘焙麦芽基质中风味化合物的总体浓度，因为这在传统产品中太低，无法实现经济有效的提取。因此，本专业将探索最大限度提高烘焙产品风味含量的创新方法，包括开发新型微波麦芽加工，通过在整个麦芽内核中进行体积加热，最大限度地提高风味发展的潜力。将应用一系列方法来确定它们在提高烘焙产品风味绝对浓度方面的有效性。例如：i)使用酶来增加风味前体的浓度。Ii)在烘焙之前，在麦芽中加入风味前体或改良剂(糖、有机酸)。3)烘烤前的碾磨，以增加热量传递的表面积。将针对每种方法研究微波加热与传统加热的影响。首席主管在谷物烘焙过程中产生热风味方面拥有丰富的专业知识[1-3]。微波工艺工程团队在微波技术的研究、开发、扩大和商业化方面拥有良好的记录，涉及不同的行业和应用。在之前的合作中，我们评估了大麦麦芽的微波/射频干燥[4]，并开发了假定的微波烘焙工艺，使我们能够收集展示具有新风味特征的烘焙产品开发的原则验证数据。微波加热提供了高度精确的温度控制，使烘焙过程能够进行微调，以最大限度地产生所需的味道，并将不需要的味道降至最低。

The brewing industry needs 'clean label' flavourings to develop novel products and improve the palatability of low and non-alcoholic beers. Hop aroma fractions extracted using liquid CO2 have achieved commercial success in this market. It is proposed that similar products, based on fractionating the diverse flavours in roasted cereal products, could prove equally successful. Advantages of this approach include sustainable and efficient product use (downstream addition) and the ability to create novel flavours by fractionation.As a pre-requisite to commercialisation it is necessary to maximise the overall concentration of flavour compounds in roasted malt substrates, since this is too low in conventional products for cost-effective extraction. This studentship will thus explore innovative ways of maximising the flavour content of roasted products, including the development of novel microwave malt processing with the potential to maximise flavour development via volumetric heating throughout the malt kernel.A series of approaches will be applied to determine their efficacy at increasing absolute concentrations of flavour in roasted products. e.g: i) the use of enzymes to increase concentrations of flavour precursors. ii) imbibing malt with flavour precursors or modifiers (sugars, organic acids) prior to roasting. iii) milling prior to roasting to increase surface area for heat transfer.The impacts of microwave versus conventional heating will be investigated for each approach.The principal supervisor has substantial expertise in thermal flavour generation during cereal roasting processes [1-3]. The microwave process engineering team have a proven track record in the research, development, scale-up and commercialisation of microwave technologies across a diverse range of sectors and applications. In prior collaborations we have evaluated microwave/ RF drying of barley malt [4] and developed putative microwave roasting processes which enabled us to gather proof-of-principle data showing the development of roasted products with novel flavour characteristics. Microwave heating offers highly accurate control of temperature profile which enables the roasting process to be fine-tuned to maximise the evolution of desirable flavours and minimise unwanted ones