降低含油量是油炸食品健康发展的保证。本研究探讨了甲基纤维素（MC）和大豆分离蛋白（SPI）两种不同种类涂膜物质对油饼含油量和抑油率的影响；通过扫描电镜（SEM）和苏丹红染色后光学显微镜（OM）观察研究MC涂膜对油脂渗透和迁移的影响，并探究MC涂膜降低含油量的机理；通过色差仪和TPA研究了涂膜对油饼感官品质的影响。结果表明：与对照组相比，两种涂膜均能显著降低油饼含油量（p<0.05），MC涂膜抑油效果优于SPI，当MC浓度为1%时抑油效果最佳，抑油率为53.77%；表面油和内部油分别降低58.66%和45.43%；通过微观结构分析发现涂膜能够使得油饼表面光滑，减少孔洞，同时能显著降低其渗透深度。这表明，涂膜可以有效降低油饼含油量，使得油饼表面结构致密，抑制油脂的渗透和迁移；且研究表明MC涂膜对样品油炸后色泽及质构影响较小，为进一步生产低油高品质油饼奠定理论基础和技术指导。

Reducing oil content is a guarantee of the healthy development of fried food. This study investigated the effects of two different types of coating materials, methylcellulose (MC) and soybean protein isolate (SPI), on the oil content and inhibition of oil absorption in Chinese deep-fried dough cake (CFDC). Scanning electron microscopy (SEM) and optical microscopy (OM) with Sudan red staining were used to examine the effects of different MC coating on oil penetration elucidate the underlying mechanism of reducing oil content by MC coating. The influence of coating on the sensory quality of CFDC was studied by colorimeter and TPA. The results showed that compared with the control, the two coatings could significantly reduce the oil content of CFDC (p<0.05), with MC performing better in inhibition of oil absorption than SPI. When the MC concentration was 1%, the inhibition of oil absorption was the greatest, with the inhibition rate being 53.77%, and the contents of the surface oil and internal oil decreasing by 58.66% and 45.43%, respectively. Microstructural analysis showed that edible coating could make the surface of CFDC smoother with fewer holes, and while significantly reducing oil penetration depth; All these results indicated that the coating can effectively reduce the oil content of CFDC, make the surface structure denser, and inhibit oil penetration and migration. This study also showed that MC coating had little influence on the color and texture of CFDC, which provides theoretical foundation and technical guidance for further production of CFDC with a low oil content but high quality.

国家重点研发计划项目（2016YFD0400401-5；2017YFC1600405-2）；国家自然科学基金资助项目（31771895；31471677）