Improving olive oil yield and quality parameters by using olivex

ABSTRACT IMPROVING OLIVE OIL YIELD AND QUALITY PARAMETERS BY USING OLIVEX KESEN, TAŞDEMİR SONGÜL M. Sc. in Food Engineering Supervisors: Assist. Prof. Dr. Esra İbanoğlu Assist. Prof. Dr. Sibel Fadıloğlu December 2000, 68 pages The aim of this study was to improve the olive oil yield of Nizip Yağlık olive variety by using olivex enzyme and to control the quality parameters of the oil such as free fatty acid content, lipid peroxidation value, UV spectrophotometer absorbance value, kreiss test and color. The optimum conditions (temperature, pH, enzyme concentration and treatment time) for the maximum activity of the enzyme were estimated. The optimum conditions were found as 35 °C, pH:5.5, the enzyme concentration of 0.06%, and the enzyme treatment time of 60 minutes. The oil yield and quality parameters were improved at optimum conditions for maximum activity of enzyme. The oil yield was found as 84%, the free fatty acids value was observed as 1%, the peroxide index was obtained as 8.2, UV spectrophotometer extinction coefficients (K232, K270) were found as 1.081 at 232 nm and 0.108 at 270 nm. Measurements of the color of oil showed that the yellowness of oil was dominant with Olivex enzyme treatment which was measured by lovibond tintometer The effect of pressing time was determined with enzyme and without enzyme at optimum conditions. The yield value increased about 1% when the pressing period was increased to 10 minute. The oil samples obtained at optimum conditions were stored for seven week at room temperature. The quality parameters were analysed during this period. The results of enzyme treated samples were observed to be better compared with the untreated samples. Key Words: Olive oil, enzyme, extraction, olive oil quality 111