不同储藏条件对油菜籽制油品质的影响

EFFECTS OF DIFFERENT STORAGE CONDITIONS ON OIL QUALITY OF RAPESEEDS

研究了储藏方式(常规密闭和充氮气调)和储藏温度(20℃、25℃、30℃、35℃)等储藏条件对不同水分(6.8%、8.3%、9.8%)的油菜籽制油品质随时间变化的规律.结果表明:在120 d的储藏过程中,油菜籽制取油脂的色泽变化不显著,储藏温度和储藏方式对于含水量较低(6.8%)的油菜籽来说,影响较小,而对于高含水量(9.8%)的油菜籽来说,温度和储藏方式对油菜籽制油品质影响较大,例如含水量9.8%的油菜籽在25℃条件下储藏120 d后,密闭储藏和充氮气调的粗脂肪酸值分别为2.55、1.45 mg/g,二者相差1.10 mg/g,35℃对应差值为1.86 mg/g,而含水量8.3%的油菜籽在25℃对应差值仅为0.15 mg/g.含水量9.8%的油菜籽在35℃储藏120 d后,密闭储藏粗脂肪酸值为4.93 mg/g,超过了国际食品法典委员会标准CODEX-STAN 210—1999《指定的植物油法典标准》规定的4 mg/g,而气调储藏粗脂肪酸值3.04 mg/g仍在规定范围内.因此,高水分油菜籽储藏时要尽量创造低温环境,在低温受限的地区,充氮气调技术可减缓高温的影响,较好地保持油菜籽的制油品质.

In this research,we studied the change rule of oil quality of different moisture contents of rapeseeds with time under different storage conditions. The results showed that the rapeseed oil had no obvious change in color during storage for 120 days;the storage temperature and storage manner had little impacts on the oil quality of low-moisture-content rapeseeds（6.8%）,but had large impacts on the oil quality of high-moisture-content rapeseeds（9.8%）. For instance,the crude fatty acid values of the high-moisture-content rapeseeds were respectively 2.55 mg/g and 1.45 mg/g after airtight storage and controlled atmosphere storage with N2 for 120 days at 25 ℃,and the difference was 1.10 mg/g; the difference between crude fatty acid values under airtight storage and controlled atmosphere storage with N2 at 35 ℃ was 1.86 mg/g; the difference between crude fatty acid values of the rapeseeds（moisture content 8.3%） was 0.15 mg/g; the crude fatty acid value of rapeseeds（moisture content 9.8%）was 4.93 mg/kg after airtight storage for 120 days at 35 ℃,which was higher than the value（4 mg/g） specified by the international Codex Alimentarius Commission standards CODEX-STAN 210- 1999 Codex Standard for Named Vegetable Oils;and the crude fatty acid value of controlled atmosphere storage was 3.04 mg/g,which was in the specified range. Therefore,low temperature environment was necessary for the storage of high-moisture-content rapeseeds; and controlled atmosphere storage with N2 could inhibit the effects of high temperature and well keep the oil quality of rapeseeds in areas with low temperature limitation.