Novel air filled emulsions as the basis for fully functional low fat foods

有必要大量减少膳食脂肪的摄入量。这里的目的是通过使用天然存在的新型表面活性剂，开发出一种低脂替代品来代替一系列传统的高脂肪食物，从而帮助实现这一目标。新的候选结构将显著降低脂质含量（预计至少降低50%）并减少膳食热量摄入。然而，该技术也应该允许携带一种不可检测的形式，否则令人不快但有益的生物活性肽或脂质。许多调味料和酱料都是高脂食品，在日常饮食中被广泛使用，如沙拉酱、蛋黄酱等。因此，它们会严重增加脂肪的摄入。这些食物增加了不同部位的脂肪摄入量；蛋黄酱可以作为高脂肪食物的调味品，也可以作为其他低脂肪沙拉的佐料。因此，选择蛋黄酱作为模型来说明所提出的食品设计和通用生产方法的应用。它打算用空气细胞代替模型系统中至少50%的脂滴。然而，为了使消费者的感觉不会受到结构变化的不利影响，通过控制空气细胞的大小和功能来保持蛋黄酱的流变性，因此满脂版本和减脂版本的口感是相同的。真菌疏水蛋白已被确定为具有稳定乳剂的巨大潜力。它们的两亲性已被证明可以稳定油乳液（非食品）和非常高的气液体积泡沫；这种稳定剂已被证明比其他常见乳化剂更稳定。增强的稳定性提供了形成具有非常高曲率角的货架稳定空气或脂质囊泡的潜力，因此可以产生小尺寸分布（1-5um），以准确地模拟蛋黄酱或敷料乳剂。疏水酶的自组装潜力提供了巨大的潜力，而不仅仅是乳液稳定。据报道，疏水性稳定的界面为小分子量溶质在界面上的运动提供了一个尺寸排斥屏障。这里，小分子指的是大于200da的分子，为生物分子分配提供了巨大的潜力。事实上，这种潜力可以通过设计具有生物功能的新型食品的能力来实现；也就是说，疏水酶稳定的空气/油水性乳液可以被设计成在每个不同的相中携带生物分子有效载荷，或者防止分子在不需要的相中分配。两类生物分子将被检查和他们的分配行为研究和开发。首先，包含一种无法检测的形式，否则极其难吃，但具有强烈生物活性的苦味肽是有吸引力的。这些短链肽已被证明具有多种有益健康的特性，包括抗高血压活性3。由于它们的苦味，它们的裸形不能用于食物中。有趣的是，苦味是它们极端疏水性的结果；因此，如果分割成稳定的脂质（即流变稳定，通过口腔存活而不破裂），并远离脂质/水界面，这些分子可能会被常规使用而不被检测到。由于苦味肽是~350 Da，它们应该适合疏水蛋白分配和界面上的竞争性吸附，应该将苦味锁定为一种不可感知的形式。其次，新的候选结构的脂质相可能来源于必需脂肪酸Omega 3和Omega 6。生物活性分子很容易氧化，通常携带强烈的有害味道，将这些化合物锁定在一种难以察觉的形式中，应该有助于消费者接受。1.生物工程学报，2005,16,434。中国生物医学工程学报，2005,88,334。J临床2003 77 326

There is a need for a substantial reduction in the amount of dietary fat. The aim here is to help achieve this by developing a reduced fat replacement for a range of traditionally high fat foods by employing naturally occurring but novel surfactants. The new candidate structures will have a significantly reduced lipid content (50% at least is envisaged) and reduce the dietary calorific intake. However, the technology should also allow for an undetectable form of, otherwise unpalatable but beneficial, bioactive peptides or lipids to be carried. Many dressings, and sauces are high lipid foods and used widely in the diet e.g. salad dressing, mayonnaise etc. As such they can contribute heavily to the fat intake. These foods have the effect of increasing the fat intake in quite disparate areas; mayonnaise as a condiment on high fat foods, or as a dressing on other wise low fat salads. Hence, mayonnaise has been chosen as a model to illustrate the application of the proposed method of food design and generic production. It is intended to replace at least 50% of the lipid droplets in the model system with air cells. However, so that consumer perception is not adversely affected by a change of the structure, the rheology of the mayonnaise will be maintained by manipulating the size and functionality of the air cells so the mouth-feel of the full and reduced fat versions are identical. Hydrophobin emulsions Fungal hydrophobins have been identified as having massive potential for the stabilisation of emulsions1. Their amphipathic nature has been shown to stabilise oil emulsions (non food) and very high gas/liquid volume foams; this stabilisation has been shown to be more stable than with other common emulsifiers2. The enhanced stability offers the potential to form shelf stable air or lipid vesicle with very high angles of curvature so that small size distributions (1-5um) may be produced to accurately mimic mayonnaise or dressing emulsions. The self assembly potential of the hydrophobins offers a huge potential beyond just emulsion stabilisation. Hydrophobin stabilised interfaces are reported to provide a size exclusion barrier to the movement of small molecular weight solutes across the interface. Here, small refers to molecules of a size greater than 200 Da and offers an immense potential for bio-molecular partitioning. Indeed, such a potential might be realised as an ability to design bio-functional novel foods; i.e. hydrophobin stabilised air/oil aqueous emulsion may be engineered to carry bio-molecule payloads in each of the distinct phases or prevent the undesirable partitioning of molecules to unwanted phases.Two classes of biomolecules will be examined and their partitioning behaviour studied and exploited. Primarily, the opportunity to include an undetectable form of otherwise extremely unpalatable but strongly bio-active bitter peptides is attractive. These short chain peptides have been shown to have a variety of beneficial health properties including anti-hypertensive activity3. In their naked form they can't be used in foods due to their associated bitterness. Interestingly though, bitterness is a consequence of their extreme hydrophobicity; and so if partitioned into a stabilised lipid (i.e. rheologically stable to survive through the mouth without rupture) and held away from the lipid/aqueous interface these molecules might be administered routinely without detection. As bitter peptides are ~350 Da they should be amenable to hydrophobin partitioning and competitive adsorption at interfaces should lock the bitterness to an unperceivable form. Secondly, the lipid phase of the new candidate structures might be derived from essential fatty acids, Omega 3 & 6. The bioactive molecules are readily oxidised and commonly carry strong unfavourable flavours and locking these compound in an unperceivable form should help consumer acceptance. 1.Curr Op Biotechnol 2005 16 434 2.Biophys J 2005 88 3434 3.Am J Clin 2003 77 326