甾醇氧化劣变导致食物营养成分损失甚至有害物质的产生，目前国内外研究主要关注自动氧化，但更重要的光诱导氧化及其烯化、聚合等变迁未见报道。本项目拟以豆甾醇、豆烷醇、豆甾醇油酸酯等代表性甾醇为研究对象，整合时间分辨光谱、色谱-质谱联用、量子化学等研究手段，建立甾醇劣变产物指纹分析方法，构建豆奶（大豆油）典型食品和相应的油/水（纯油）模拟甾醇光氧化劣变体系；探索甾醇光诱导氧化发生的作用位点、反应历程及其动力学；探明光诱发后甾醇进一步氧化、烯化、聚合或裂解等变迁主要历程和标志产物，揭示光照、光敏物质、甾醇结构、食物组分、金属离子和氧气等因素及其互作对甾醇光氧化变迁主要历程的影响规律，阐明典型食品体系甾醇光氧化诱导发生及其变迁的劣变机理；从包装方式、加工方式、抗氧化剂等方面提出典型食品体系甾醇光氧化诱发及其变迁的关键控制点和阻控措施。项目的实施将为甾醇的健康安全食用和稳定贮藏加工奠定科学基础。

Phytosterols are vulnerable to oxidizing into phytosterol degradation products, thereby causing the loss of food nutrition and the generation of hazardous and noxious substances, However, most of the present studies from domestic and foreign country mainly focus on phytosterol thermal oxidation, whereas few studies are reported on photooxidation deterioration in olefination, polymerization and other pathways.. This study aims to analyze the composition of phytosterols (stigmasterol, stigmastanoland stigmasterol oleate, selected as representative phytosterols) and thepathways and kinetics of deterioration induced by light, by using method combined with time-resolved spectrum, chromatographic-mass spectrometric, food chemistry, metabonomics and chemometrics. On the basis of existing research, the multiple analog deterioration system of typical (milk beverage, corn oil) and model (oil/water, oil) food will be established.And the phytosterols and their deterioration products in these food systems will be further detected by holographic fingerprint method, then the main deterioration pathways and mark products of deterioration products will be summarized using information and space-time characterization from the fingerprint. The regulation and mechanisms of degradative phytosterols will be studied under the influence of different factors, such as lighting, heating, various of phytosterol structures, food ingredient, antioxidant, photosensitive material, metal ions, and oxygen; the keypoints of control and regulatory pathway of phytosterols photoprotection in typical food system will be discussed based on modulation of packaging, processing methods, antioxidants and ingredients. This study lays a scientific foundation for healthy diet and stable storage of phytosterols.