Effect of frying oil on the properties of donut

Abstract

In this paper, we determined the key factors of frying oil and developed the most suitable oil for donuts. First, we investigated the correlations between the physical properties of frying oil and the palatability of donuts using sensory evaluation. As a result, fats with a high slip melting point (> 40°C) prevented the oily appearance of donuts during storage, while those with a solid fat content of 20% at 30deg;C imparted a favorable taste and texture to the donuts. On this basis, we developed "donut-oil" (soft palm middle fraction (sPMF) : randomly transesterified oil : emulsifier=59.6 : 40.0 : 0.4) with both a high slip melting point (46.3°C) and a solid fat content of 21.8% at 30°C. Further, we evaluated the digestibility of the "donut-oil" in both rats and humans. Fecal excretion was significantly greater in rats fed sPMF or the "donut-oil" than in those fed corn oil. In humans, fecal fat excretion was significantly higher (p<0.001) in the "donut-oil" group (2.89±0.24g/day) than in the canola oil group (1.04±0.11 g/day). These results indicated that "donut-oil" has lower digestibility than the liquid vegetable oils.