研究了油脂氧化酸败测定仪的操作参数温度、空气流速、样品量对油茶籽油化稳定指数(Oxidative Stability Index),温度系数,Q10的测定及货架期预测的影响。为了这个目的,试验数据建立了完全二次模型并且进行了方差分析,结果表明温度和空气流速对OSI的影响显著(P〈0.01)。此外,通过简化的线性模型检测表明在温度占主导效应的同时,与样品量相比,空气流速对油茶籽油OSI的测定也有较大的影响(P〈0.05)。此项研究获得的油茶籽油温度系数平均值为-3.02×10-2。Q10的计算平均值为2.02,表明温度每升高10℃油茶籽油的OSI减半。计算出的20℃下的OSI表现出明显不同,说明空气流量和样品量对油茶籽油货架期的预测有着很大影响。因此,在油脂氧化酸败测定过程中选择一个合适的操作参数水平会降低长期室温贮藏和加速氧化对货架期预测的影响。
Operational parameters of the Rancimat method including temperature,airflow rate and oil sample size have been evaluated to determine their effects on oxidative stability index( OSI),temperature coefficient,Q10 and shelf- prediction of camellia oil. Experimental data have been established to a complete quadratic model. ANOVA analysis was performed and indicated that the airflow rate and temperature could be significant( P〈 0. 01). In addition,a simplified linear model was assayed to also result that as the temperature dominated the effect,compared with the sample amount,air flow rate had a great effect for the determination of camellia oil OSI( P〈 0. 05) as well. The study results showed the mean value of camellia oil temperature coefficient of 3. 02 × 10- 2. A mean value of 2. 02 calculated for the Q10 number indicated that an increase of 10 ℃ approximately halved the OSI of camellia oil. The calculated OSIs for the treatments combinations at 20 ℃( OSI20) showed that there were statistically significant differences,namely,indicated that the airflow rate and oil sample size had certain effect on the shelf- prediction of camellia oil. In Rancimat method,therefore,to select the suitable operating parameters coule be a method of reducing the effect of long- term storage at room temperature and accelerate oxidation on shelf life prediction.