Department of Food Physics and Meat Science, University of Hohenheim , Garbenstrasse 21/25, 70599 Stuttgart, Germany.
Chair of Food Chemistry and Molecular Sensory Science, Technical University of Munich , Lise-Meitner-Strasse 34, 85354 Freising, Germany.
J Agric Food Chem. 2017 May 24;65(20):4153-4160. doi: 10.1021/acs.jafc.7b00441. Epub 2017 May 10.
The interfacial and emulsion-forming properties of sugar beet extract (Beta vulgaris L.) were examined and compared to a Quillaja extract that is widely used within the food industry. We investigated the influence of extract concentration on surface activity at oil-water and air-water interfaces and on the formation of oil-in-water emulsions (10% w/w, pH 7). Sugar beet extract reduced the interfacial tension up to 38% at the oil-water interface, and the surface tension up to 33% at the air-water surface. The generated emulsions were negatively charged (ζ ≈ -46 mV) and had the smallest particle sizes (d) of ∼1.3 μm at a low emulsifier-to-oil ratio of 0.75:10. Applying lower or higher extract concentrations increased the mean particle sizes. The smallest emulsions were formed at an optimum homogenization pressure of 69 MPa. Higher homogenization pressures led to increased particle sizes. Overall, sugar beet extract showed high surface activity. Furthermore, the formation of small emulsion droplets was successful; however, the droplets were bigger compared to those from the Quillaja extract. These results indicate sugar beet as an effective natural emulsifier that may be utilized for a variety of food and beverage applications.
我们研究了甜菜提取物（Beta vulgaris L.）在油水和气水界面上的界面和乳化性能，并与在食品工业中广泛使用的奎那亚提取物进行了比较。我们研究了提取物浓度对油-水和空气-水界面上表面活性以及水包油乳液形成（10％w/w，pH 7）的影响。甜菜提取物将油水界面处的界面张力降低了 38％，将空气-水表面处的表面张力降低了 33％。生成的乳液带负电荷（ζ≈-46 mV），在乳化剂与油的比例为 0.75:10 时，粒径最小（d）约为 1.3μm。应用较低或较高的提取物浓度会增加平均粒径。在 69 MPa 的最佳均质压力下形成最小的乳液。更高的均质压力会导致粒径增加。总体而言，甜菜提取物具有很高的表面活性。此外，成功形成了小的乳液液滴；但是，与来自奎那亚提取物的液滴相比，这些液滴更大。这些结果表明，甜菜是一种有效的天然乳化剂，可用于各种食品和饮料应用。
