乳脂肪含量与脂肪球结构对乳茶体系涩感感知的影响研究

Effects of Milk Fat Content and Fat Globule Structure on Perception of Astringency in Milk Tea System

摘要:

乳茶饮料是广受消费者喜爱的一种饮品，茶汤中丰富的茶多酚导致的涩感是影响乳茶饮料感官质量的关键因素之一。已有研究显示乳组分如乳蛋白等能够降低涩感，乳脂肪由乳脂肪球组成，作为牛乳中的一种重要组成成分，其含量和结构对乳茶体系涩感的影响尚不明确。为探究牛乳脂肪含量及脂肪球结构对乳茶体系中涩感的影响，首先通过描述型感官评价探究乳脂肪及其含量对乳茶体系涩感是否有影响。然后，研究通过调控加热强度和均质压力，构建了3种脂肪含量一致但结构特征不同的乳脂滴：乳脂滴C、乳脂滴T和乳脂滴H，并通过测定粒径、ζ-电势、微观结构、乳脂肪球膜蛋白含量和组成、乳脂肪球膜磷脂含量表征乳脂肪球特性，再将不同乳脂滴添加至模拟乳茶体系，进行涩感强度的感官评价，并通过荧光光谱分析量化涩感差异。结果表明，当乳脂肪质量浓度达到4g/(100mL）以上时，乳脂肪的添加可显著降低乳茶中的涩感水平。此外，改变乳脂肪球的粒径及膜结构也对乳茶体系的涩感有显著影响。与其他两种乳脂滴相比，乳脂滴H中的脂肪球粒径最小（0.49μm），每克脂质的蛋白质量最高（12.60mg），而涩感最弱。乳脂滴T粒径最大（4.20μm），每克脂质的蛋白质量最低(4.12mg)，涩感较强。因此，乳脂肪含量、粒径和膜结构会影响乳茶体系的涩感强度，更小的乳脂肪球尺寸和更多的乳脂肪球膜界面蛋白对乳茶体系的涩感强度降低作用更大。研究探究了乳脂肪对乳茶体系涩感感知的影响，为口感更顺滑的绿色、健康乳茶饮料的开发奠定了理论基础。

Abstract:

Milk tea beverage is a drink widely loved by consumers. The astringency caused by the rich tea polyphenols in the tea soup is one of the key factors affecting the sensory quality of milk tea beverage. Existing research has shown that milk components, such as milk proteins, can reduce astringency. Milk fat, an important component in cow’s milk, is composed of milk fat globules. However, the effect of its content and structure on astringency in milk tea systems remained unclear. It was aimed to investigate the impact of milk fat content and fat globule structure on astringency in milk tea systems. Firstly, it used descriptive sensory evaluation to explore whether milk fat and fat content affected the astringency of milk tea system. Next, three types of milk fat droplets with the same fat content but different structural characteristics were constructed by adjusting the heating intensity and homogenization pressure: milk fat droplet C, milk fat droplet T and milk fat droplet H, and the particle size, ζ-potential, microscopic structure, milk fat globule membrane protein content and composition, and milk fat globule membrane phospholipid content were measured, which characterized the characteristics of milk fat globules. Then different milk fat droplets were added to the simulated milk tea system to conduct sensory evaluation of astringency intensity, and quantify astringency through fluorescence spectroscopy analysis. The results showed that when the milk fat content reached above 4g/(100mL), the addition of milk fat can significantly reduce the astringency level in milk tea. In addition, changing the particle size and membrane structure of milk fat globules also had a significant impact on the astringency of the milk tea system. Compared with the other two milk fat droplets, the fat globule size in milk fat droplet H was the smallest (0.49μm), the protein content per gram fat globule membrane was the highest (12.60mg), and the astringency was the weakest. Milk fat droplet T had the largest particle size (4.20μm), the lowest protein content per gram fat globule membrane (4.12mg), and a strong astringency. Therefore, milk fat content, particle size and membrane structure would affect the astringency intensity of milk tea system. Smaller milk fat globule size and more milk fat globule membrane interface proteins had the greatest effect on reducing the astringency intensity of milk tea system. It was confirmed the impact of milk fat on the perception of astringency in the milk tea system, laying a theoretical foundation for the development of green and healthy milk tea drinks with a smoother taste.