精炼过程对大豆油回色的影响

Effect of refining process on the color reversion of soybean oil

从大豆油精炼生产工艺出发,考察γ-生育酚、磷、金属离子等影响大豆油回色的微量成分在精炼过程中的含量变化及其与辅料添加量、脱臭条件对储存期成品大豆油回色的影响。结果表明:γ-生育酚在脱臭工段损失最大,建议脱臭温度在250℃以下,而辅料和汽提蒸汽压力的微调对其影响不大;水化磷脂基本在脱胶工段可以彻底脱除,酸炼脱胶主要脱除非水化磷脂,建议将磷含量控制的关键环节设置在脱胶工段,以降低脱色工段白土吸附除磷的压力和生产成本;金属离子基本可以在正常的脱酸、脱色工段利用皂脚和脱色剂吸附脱除;γ-生育酚损失率、脱臭油的磷含量与储存期成品大豆油的回色呈正相关,而金属离子与回色无相关性;脱色剂种类配比对不同产地大豆油的回色无显著影响;而高柠檬酸添加量对储存1个月的大豆油回色有抑制作用,但随储存时间的延长,抑制作用不明显;脱臭温度、汽提蒸汽压力对美国大豆油的回色影响不大,但对巴西大豆油回色影响较明显。

From the refining process of soybean oil,the content changes of trace components affecting the color reversion of soybean oil,such asγ-tocopherol,phosphorus and metal ions during the refining process,and their influence on the colour reversion of finished soybean oil in the storage period together with the addition of auxiliary materials and deodorization conditions were investigated.The results showed thatγ-tocopherol lost the most in the deodorization process.It was recommended that the deodorization temperature should be below 250℃,and the fine-tuning of the auxiliary materials and the stripping steam pressure had little effect onγ-tocopherol;the hydrated phospholipids could basically be completely removed in the degumming process,and the acid degumming was mainly to remove non-hydrated phospholipids,it was recommended to set the key link of phosphorus content control in the degumming section to reduce the pressure and production cost of the bleaching section of the clay to adsorb and remove phosphorus;metal ions could basically be removed by adsorption of soap stock in deacidification and adsorbents in bleaching.The loss rate ofγ-tocopherol and phosphorus content in deodorized oil were positively correlated with the color reversion phenomenon of finished soybean oil during storage,while metal ions had no correlation with color reversion;the dosage of adsorbents and mixed ratio of compound adsorbents had no correlation with the color reversion of soybean oil from different regions.The high citric acid addition inhibited the color reversion of soybean oil stored for one month,but this inhibition was less pronounced as the storage period was extended.The deodorization temperature and stripping steam pressure had no significant correlation with the color reversion of American soybean oil,but it had a significant impact on the color reversion of Brazilian soybean oil.