Pycarelle Sarah C, Bosmans Geertrui M, Pareyt Bram, Brijs Kristof, Delcour Jan A
Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium.
Puratos NV, Industrialaan 25, 1702 Groot-Bijgaarden, Belgium.
Foods. 2021 Jan 6;10(1):107. doi: 10.3390/foods10010107.
The main sponge cake ingredients are flour, sucrose, eggs and leavening agents. Exogenous lipids (e.g., monoacylglycerols) are often used to increase air-liquid interface stability in the batter. There is a consumer trend to avoid foods containing such additives. We here reasoned that egg yolk may be an alternative source of surface-active lipids and set out to study the role of egg yolk lipids during sponge cake making. This was done by relocating or removing them prior to batter preparation using ethanol treatments and examining how this affects cake (batter) properties and structure setting during baking. Most egg yolk lipids occur within spherical low-density lipoproteins (LDLs) which were disintegrated by the ethanol treatments. Results showed that egg yolk lipids impact air-liquid interface stability and less so cake structure setting. To prepare high-quality sponge cakes by multistage mixing preferably intact LDLs or, alternatively, their components are needed to incorporate sufficient air during mixing and to stabilize it after mixing. It was also shown that the batter contains intact LDLs in the continuous phase and disintegrated LDLs at air-liquid interfaces. Sponge cake contains intact LDLs in the cake matrix, disintegrated LDLs at air-crumb interfaces and disintegrated LDLs incorporated into the protein network.
海绵蛋糕的主要原料是面粉、蔗糖、鸡蛋和膨松剂。外源性脂质（如单酰甘油）常用于提高面糊中气液界面的稳定性。消费者有避免食用含有此类添加剂食品的趋势。我们由此推断蛋黄可能是表面活性脂质的替代来源，并着手研究蛋黄脂质在海绵蛋糕制作过程中的作用。这是通过在制备面糊前用乙醇处理来重新定位或去除蛋黄脂质，并研究其如何影响烘焙过程中蛋糕（面糊）的性质和结构形成来实现的。大多数蛋黄脂质存在于球形低密度脂蛋白（LDL）中，乙醇处理会使其分解。结果表明，蛋黄脂质影响气液界面稳定性，对蛋糕结构形成的影响较小。要通过多阶段搅拌制备高质量的海绵蛋糕，最好使用完整的低密度脂蛋白，或者其成分，以便在搅拌过程中融入足够的空气并在搅拌后使其稳定。研究还表明，面糊在连续相中含有完整的低密度脂蛋白，在气液界面含有分解的低密度脂蛋白。海绵蛋糕在蛋糕基质中含有完整的低密度脂蛋白，在气-面包屑界面含有分解的低密度脂蛋白，并且有分解的低密度脂蛋白融入蛋白质网络。
