QUANTITATIVE ANALYSIS OF OIL LOSS DURING THE EDIBLE OIL REFINERY PROCESS

Abstract

Unilever Ceylon Limited is one of major manufacturing companies in Sri Lanka and its major products are detergents, foods and personal products. The total annual production is approximately 81000 tons o f which 70 % is from detergents, 22 % from foods and 8 % from personal products. Edible oil refining is one of the major processes in food production. The activity in the refinery, which is entirely batch based, includes neutralization, deodorization, intereterification and bleaching. In order to maintain the efficiency and to minimize the oil loss during the refinery process, regular monitoring was important. Therefore free fatty acid content in original oil blend, total fatty matter in the soap stock and neutral oil in soap stock were monitored for different batches o f Astra oil blends during December to 31st o f January. Free fatty acid content in the oil blend and Total fatty matter in the soap stock was determined using Unilever Method of Analysis and the neutral oil content in the soap stock was determined using A.O.C.S. Official method (G 5-40). According to the results mean value o f the TFM (%) is 4.99 ± 1.33 and the standard deviation is 2.31 ±1.02. The distribution of TFM (%) is positively skewed. Kurtosis of the distribution shows that the peakness o f the distribution is higher than the normal and equal number o f observations lie below and above the mean. The TFM (%) of the soap stock varied irregularly during the two months and a strong quadratic relationship between the TFM (%) and the FFA (%). The (%) neutral oil content is 0.32±0.13 and the standard deviation of the distribution is 0.20 ± 0.09. The distribution is positively skewed. Kurtosis shows that the distribution is flatter than the normal. Most o f the (%) neutral oil values exist below and around the mean value. The results of (%) neutral oil content has been fluctuated irregularly during the two months of analysis but at a very low level.