一个朋友在豆油厂上班,他告诉我:豆油在加工时添加了一种有机溶剂,叫六号轻气油,利用相似相溶原理,提高大豆的出油率,最后在一定压力和温度下蒸发溶剂,问题是出来的成品油一定会有溶剂残留的,多少而已,只要符合相关标准就行,所以,他家吃油不管哪种油,只选压榨的。
Low temperature pressing
听到这些,我惊讶了,心想:你说的能是真的吗? 溶剂残留真的不能去除干净? 吃了这些年,我的身体也没发现有什么问题啊! 再说,食用油GB标准可是国家发布的,这么权威的标准肯定是安全的,你只选择压榨,是不是以点概面、以偏概全了!
GB Standard
可是又一想,不对啊,朋友有必要夸大事实吗? 如果是真的,岂不是无知害了我! 于是,经过一系列学习后,得出结论,它的成分是正己烷和环己烷,属烷烃类有机化合物,有毒(毒性根据浓度判定),新标准GB/T 1535-2017《大豆油》规定,合格的浸出一级成品大豆油不得检出溶剂残留量,二级、三级应小于20mg/kg(旧标准≤50mg/kg),一般来讲,合格的浸出大豆油须遵循溶剂残留量规定,即使油中有极微量的容剂残留 , also does not hinder human health. However, if the amount of solvent residue in the edible oil is too high, long-term exposure will damage the human nervous system and hematopoietic system.
N-hexane is lowly toxic and cyclohexane evaporation is toxic
当看到这里时,脑袋懵懵的,原来认为有GB标准放在那呢! 选择大品牌是没问题的,结果网上一查,大品牌也出现过超标问题,于是,我又仔细学习了一下,发现:
压榨工艺中,冷榨也叫低温压榨;鲜榨只能说明用的是当季的新鲜豆子,采用高温压榨;熟榨就是高温压榨;精榨采用的也是高温压榨,进行精加工,等级一级。
浸出工艺中,有机溶剂残留在标准范围内就是安全的,但是出油率比压榨高。
理论上,不论哪种工艺,营养三级大于一级;杂质去除程度一级大于三级。
However, if you dig deeper, you will find that, first, after high-temperature pressing and high-temperature gas extraction during processing, how much nutrients are retained? Second, in the process of high temperature, do trans fatty acids are produced? 第三,在加工的其它环节比如脱色工艺,采用的脱色剂,经过处理后是否还有微量残余? Fourth, the brand of soybean oil has exceeded the standard problem, will the small workshop oil meet the standard?
Therefore, soybean oil is eaten every day, not necessarily you understand it, or that sentence, from different angles to comprehensively and objectively look at the problem, multi-faceted trade-offs!