Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China.
International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu, China.
J Food Sci. 2020 Oct;85(10):3150-3159. doi: 10.1111/1750-3841.15411. Epub 2020 Sep 7.
This study investigated the effects of preheat treatments on the composition, rheological properties, and the physical stability of soybean oil bodies and examined the stability of coffee containing those oil bodies. Three preheat treatment methods were compared, including heating (at 65, 75, and 85 °C for 30 min) of raw soymilk, high-pressure steam heating (at 110, 120, and 130 °C for 10 s, ultra high temperature [UHT] treated) of dry soybeans, and milling of soaked soybeans in boiling water. Three UHT samples showed the highest oil body yields (13.59 to 13.87%) and protein yield (2.47 to 3.03%), while oil content in extracts was the lowest (30.97 to 46.25%). Soymilk heated at 65 or 75 °C for 30 min showed high oil body extraction yields (13.38 and 11.46%) and the highest oil extraction yields (6.38 to 8.38%) among all the samples. Three UHT samples had a higher average particle size and higher apparent viscosity compared with those of all the other samples. The results from sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and particle size distribution suggested heat treatment at 65 to 85 °C just lead to the partially denaturation and unfolding of storage protein instead of severe aggregation, while UHT (samples 5, 6, and 7) could lead to large amount soluble aggregates within oleosins and storage proteins via disulfide bonds. The diluted emulsion with 12% fat content remained stable during a 15-day storage period at 4 °C. The coffee stability of the diluted oil body emulsion indicated high oleosins and low storage protein content in the oil body was a benefit for the coffee stability. PRACTICAL APPLICATION: Soybean oil bodies are natural sources of pre-emulsified oil derived from soybean and can be dispersed in an aqueous medium to form a stable emulsion system. This study provides the foundation for the preparation and application of soybean oil bodies with differing emulsion stabilities and extraction yields in the food industry.
本研究考察了预热处理对大豆油体的组成、流变特性和物理稳定性的影响，并研究了含有这些油体的咖啡的稳定性。比较了三种预热处理方法，包括生豆浆加热（65、75 和 85°C 加热 30 分钟）、干豆高压蒸汽加热（110、120 和 130°C 加热 10 秒，超高温 [UHT] 处理）和浸泡大豆在沸水中研磨。三种 UHT 样品的油体得率（13.59 至 13.87%）和蛋白质得率（2.47 至 3.03%）最高，而提取物中的油含量最低（30.97 至 46.25%）。在 65 或 75°C 加热 30 分钟的豆浆显示出较高的油体提取产率（13.38 和 11.46%）和最高的油提取产率（6.38 至 8.38%）。三种 UHT 样品的平均粒径较高，表观粘度较高，与所有其他样品相比。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）和粒径分布的结果表明，65 至 85°C 的热处理只是导致储存蛋白部分变性和展开，而不是严重聚集，而 UHT（样品 5、6 和 7）可能会导致大量的可溶聚集体在油体和储存蛋白内形成通过二硫键。在 4°C 下储存 15 天期间，脂肪含量为 12%的稀释乳液保持稳定。稀释油体乳液的咖啡稳定性表明油体中的高油体和低储存蛋白含量有利于咖啡的稳定性。实际应用：大豆油体是天然来源的预乳化油，源自大豆，可分散在水介质中形成稳定的乳液体系。本研究为在食品工业中制备和应用具有不同乳液稳定性和提取产率的大豆油体提供了基础。
