As the raising and wide acceptance of concept of moderate refining of edible vegetable oil,indexes for acid value,color,etc.in the vegetable oil national standard starts to be loosened,leading to the content change of other components except for triglyceride in the vegetable,especially phospholipid,solvent,peroxide,moisture,volatile matter,etc,which have an effect on smoke point.Although the mathematical relationship between smoke point and free fatty acid has been studied aiming at free fatty acid belonging to quality index to be loosened,influence of change of other components caused by loosening of acid value on smoke points havenl gained comprehensive consideration.Therefore,in this study,rapeseed oils with different contents of free fatty acid,phospholipid,peroxide,residual solvent,moisture and volatile matter were collected and compounded to generate vegetable oil samples with different components.After measuring smoke point and contents of various indexes,use principal component regression method to gain regression equation between various element and smoke point:Ln (smoke point) =5.006-0.029 × Ln (acid value)-0.041 × Ln (peroxide value)-0.003 × Ln (residual solvent content)-0.039 × Ln (phosphorus content)-0.044 × Ln (moisture and volatile matter) (R2 =0.926).The impact of various factors was the moisture and volatile matter,peroxide value,phosphorus content,acid value and solvent residue in an order from big to small.%随着食用植物油适度精炼理念的提出和被广泛认可,植物油国标中对酸值、色泽等指标开始放宽,而这种放宽会导致植物油中其他的非甘油三酯组分的含量,尤其是对烟点有影响的磷脂、溶剂、过氧化物、水分及挥发物等组分发生变化,进而影响植物油的烟点.尽管针对游离脂肪酸这一将放宽的质量指标,其与烟点间数学关系已有研究,但酸值的放宽引起的其他组分的变化对烟点的影响并未能综合考量.因此,通过实验室模拟的方法,采集不同游离脂肪酸、磷脂、过氧化物、溶剂残留、水分及挥发物的菜籽油,进行复配,获得组分不同的植物油样品,测定烟点及各指标含量,利用主成分回归的方法得到各因素与烟点间的回归方程:ln烟点=5.006-0.029×ln酸值-0.041×ln过氧化值-0.003×ln溶残-0.039×ln含磷量-0.044×ln水分及挥发物,R2 =0.926,结果表明,各因素的影响程度大小由大到小分别为水分及挥发物、过氧化值、含磷量、酸值、溶残.
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