冷榨油茶籽毛油脱胶与脱色工艺研究

Study on the process of degumming and decoloring of cold-pressed crude oil-tea Camellia seed oil

目的研究柠檬酸、磷酸对冷榨油茶籽毛油酸法脱胶效果,活性白土和活性白土与活性炭复合吸附剂对冷榨油茶籽毛油脱色脱胶的效果。方法从酸种类、酸添加量、加水量、温度、时间、搅拌转速方面考察了冷榨油茶籽毛油酸法脱胶效果;从吸附剂种类、吸附剂添加量、温度、时间、搅拌转速方面考察了冷榨油茶籽毛油吸附脱色脱胶效果;此外分别从2个工艺考察了上述参数变化对冷榨油茶籽毛油的酸价、过氧化值的变化情况。结果酸法脱胶柠檬酸添加量为油重的0.5%,温度为90℃,时间为30 min,加水量为油重的3%,搅拌转速为60 r/min时,油茶籽毛油脱胶率为49.39%;吸附脱色脱胶活性白土添加量为油重的2%,温度45℃,时间10 min,搅拌转速100 r/min时,油茶籽油脱胶率为51.39%,脱色率为95.74%, 2种工艺对油茶籽油酸价均无显著影响,酸法脱胶由于高温操作使得过氧化值升高,吸附脱色脱胶能够降低过氧化值。结论添加少量活性白土吸附脱色的同时能够达到与酸法脱胶相当的脱胶效果,同时能够改善油茶籽毛油的色泽、透明度和过氧化值,且工艺无需使用酸和水,故油茶籽毛油精炼工艺中可以考虑省去酸法脱胶工序。

Objective To study the effect of citric acid and phosphoric acid on the degumming effect of cold pressed crude oil-tea camellia seed oil, and the effect of activated clay, composite adsorbent(activated clay and activated carbon) on the decolorization and degumming of cold pressed crude oil-tea camellia seed oil. Methods The effect of cold-pressed crude oil-tea camellia seed oil on degumming by acid method was investigated from the aspects of acid type, acid addition, water addition, temperature, time and stirring speed;the effect of cold-pressed crude oil-tea camellia seed oil on adsorption, decolorization and degumming by adsorption method was investigated from the adsorbent type, adsorbent addition amount, temperature, time and stirring speed;in addition, the changes in the acid value and peroxide value of cold-pressed crude oil-tea camellia seed oil on the changes of the above parameters were also investigated. Results The degumming rate of crude oil-tea camellia seed oil with acid method was 49.39%, when citric acid added 0.5% of oil weight, temperature was 90 ℃, time was 30 min, water added was 3% of oil weight, and the stirring speed was 60 r/min. The adsorption method was 51.39% and decolorization rate was 95.74%, when activated clay added was 2% of the oil weight, the temperature was 45 ℃, the time was 10 min, and the stirring speed was 100 r/min. Both processes had no effect on the acid value. Significantly, the peroxide value of acid degumming increased due to high temperature operation, and the adsorption method could reduce the peroxide value. Conclusion Adding a small amount of activated clay for decolorization can achieve the degumming effect equivalent to acid degumming. At the same time, it can improve the color, transparency and peroxide value of crude oil-tea camellia seed oil, and the process does not need to use acid and water, so the acid degumming process is not necessary in the refining process of crude oil-tea camellia seed oil.