Identifying key interactions to reduce astringency of novel food proteins

确定减少新型食品蛋白质涩味的关键相互作用

• 批准号: 2547521
• 金额: --
• 依托单位: King's College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2547521
• 关键词: Identifying; key; interactions; reduce; astringency

The development of new plant-based or synthetic sources of protein for human consumptionis a major aim of the BBSRC as part of the Bioscience for sustainable agriculture theme. Todate the need for high protein foods has been achieved by increased animal farming but theenvironmental impact of this is now being realised. As a consequence a recent developmenthas been the formulating of synthetic proteins and the increased use of plant derived proteinsin the creation of structured foods. Improving the consumer liking of these new foods isessential to their acceptance and growth of this new industry, in which the UK is a leadingplayer. However, the development of novel food proteins has reached a bottleneck as manyof these types of protein cause excessive oral astringency when consumed. Astringency isthe dry, puckering sensation in the mouth often associated with tannins in tea and wine. Atlow levels astringency can be a refreshing sensation which is enjoyed by the consumer but athigher levels it is inhibitory to ingestion. The mechanism of how tannins cause astringency isreasonably well understood. Phenol rings within the catechins (which are the mainpolyphenols in tea and wine) stack onto proline-rings within salivary proteins such as Prolinerichproteins and mucins by hydrophobic-hydrophobic interactions. This binding then causesa reduction in oral lubrication possibly by depleting the hydration layer around the salivaryproteins and a loss of lubrication. This loss of lubrication is perceived as dryness, eventhough liquid is still in abundance. For protein induced astringency we only have limited datafor whey protein, derived from milk, which is commonly used for muscle-building/ nutritiondrinks. Whey proteins are astringent by forming electrostatic interactions with salivaryproteins although the evidence relates only to in vitro experiments and not completelyunderstood. It is likely that electrostatic interactions are important in causing astringency asa number of chemicals can also cause the same sensation. Alum, for example, is a hydratedaluminium sulphate salt which is widely known to cause astringency and does so by affectingthe conformation of salivary proteins to affect their lubrication. As yet there are no knownreceptors for astringency and the perceived dryness is assumed to be detected by alteredtouch and proprio-receptor activation in the mouth. If we can understand the nature of theinteractions between food proteins and salivary proteins it may be possible to screen potentialnew food proteins for astringency and develop methods to modify the protein to reduce theseinteractions. This is of particular importance to Motif as they will be screening large numbersof potential proteins from their partner Gingko for development as food proteins.Thus the overall aim of this project is to identify the mechanism of oral astringency caused byfood proteins. To achieve this aim we will test the hypothesis that electrostatic interactionsare the main interface between food proteins and salivary proteins. To achieve this theobjectives for the project are:1) To vary electrostatic interactions between food proteins and salivary proteins2) Identify protein motifs that create charge interactions3) Examine the role of counter ions in disrupting astringencyTo conduct this project the student will combine physiology with protein biochemistry and usestructural biology to examine the nature of the interactions in detail.

开发供人类消费的新的植物基或合成蛋白质来源是 BBSRC 的主要目标，作为可持续农业生物科学主题的一部分。迄今为止，对高蛋白食品的需求已通过增加动物养殖来满足，但其对环境的影响现已逐渐认识到。因此，最近的发展是合成蛋白质的配制以及在结构食品的生产中增加使用植物来源的蛋白质。提高消费者对这些新食品的喜爱程度对于他们接受和发展这个新行业至关重要，而英国在该行业中处于领先地位。然而，新型食品蛋白质的开发已达到瓶颈，因为许多此类蛋白质在食用时会导致过度的口腔涩味。涩味是指口腔中干燥、起皱的感觉，通常与茶和酒中的单宁有关。低水平的涩味可以是消费者喜欢的清爽感觉，但高水平的涩味会抑制摄入。单宁引起涩味的机制已相当清楚。儿茶素（茶和酒中的主要多酚）内的苯酚环通过疏水-疏水相互作用堆积在唾液蛋白（例如富含脯氨酸蛋白和粘蛋白）内的脯氨酸环上。然后，这种结合可能通过耗尽唾液蛋白周围的水合层和润滑损失而导致口腔润滑减少。尽管液体仍然充足，但这种润滑损失被认为是干燥。对于蛋白质引起的涩味，我们只有有限的乳清蛋白数据，乳清蛋白来源于牛奶，通常用于增肌/营​​养饮料。乳清蛋白通过与唾液蛋白形成静电相互作用而具有收敛性，尽管证据仅涉及体外实验并且尚未完全理解。静电相互作用很可能在引起涩味方面很重要，因为许多化学物质也会引起同样的感觉。例如，明矾是一种水合硫酸铝盐，众所周知，它会产生涩味，并通过影响唾液蛋白质的构象来影响其润滑作用。迄今为止，还没有已知的涩味受体，并且认为干燥感是通过改变触觉和口腔中固有受体激活来检测的。如果我们能够了解食物蛋白质和唾液蛋白质之间相互作用的本质，就有可能筛选潜在的新食物蛋白质的涩味，并开发修饰蛋白质的方法以减少这些相互作用。这对 Motif 来说尤其重要，因为他们将从合作伙伴 Gingko 中筛选大量潜在蛋白质，用于开发为食品蛋白。因此，该项目的总体目标是确定食品蛋白引起口腔涩味的机制。为了实现这一目标，我们将检验静电相互作用是食物蛋白质和唾液蛋白质之间的主要界面的假设。为了实现这一目标，该项目的目标是：1）改变食物蛋白和唾液蛋白之间的静电相互作用2）识别产生电荷相互作用的蛋白质基序3）检查抗衡离子在破坏涩味中的作用为了进行这个项目，学生将结合生理学和蛋白质生物化学，并使用结构生物学来详细检查相互作用的性质。