DETERMINATION OF BENZO(a)PYRENE IN VEGETABLE OILS BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Analysis of 40 oil samples showed that 38 of them were contaminated with benzo(a)pyrene (BaP). Thirty of the 38 BaP‐contaminated edible oil samples did not have any label of a brand name. BaP content for the 38 contaminated edible oil samples were in the range of 1.22–74.89 ppb. Sixteen of the contaminated oil samples had BaP content of more than 10 ppb, which is the maximum tolerable limit for the Turkish Food Codex Regulation. BaP contents of samples for each type of oil were significantly different (P < 0.05) from each other.     

TELEME PRODUCTION BY PURIFIED FICIN

Fig tree latex (ficin) was stepwise purified by ion exchange chromatography on carboxymethyl (CM)-cellulose and gel filtration chromatography on Sephadex G-100, and then utilized in the production of teleme. Following ion exchange chromatography, the milk clotting to proteolytic activity ratio (MCA/PA) increased from 1.97 to 3.1 and following gel filtration, to 7.4. The purified fraction gave better chemical and sensory properties than teleme made by fig tree latex. The protein content of teleme made by fig tree latex and the purified fraction were 3.90 and 6.50%, respectively. Syneresis in teleme decreased from 95% to 85% upon purification of the proteolytic enzymes. Exclusion of proteolytic activity appears to be essential to improve the quality of teleme.     

Nitrite Effects on Formation of Volatile Oxidation Products from Triolein

Oxidation of triolein resulted in the formation of 5 major aldehydes (heptanal, octanal, nonanal, 2-decenal and 2-undecenal). Pre-treatment of the triolein with a twofold molar excess of N₂O₃ did not qualitatively affect the compounds formed but reduced the amount formed by 63 to 74%. Treatment with tenfold excess of N₂O₃ resulted in formation of several unknown compounds. However, the ratio of N₂O₃ to olefinic groups in lipids in cured meats was less than 1:750. These data indicate that nitrite reduced the formation of aldehydes from lipid oxidation and contributed to anti-oxidant activity. However, the amount of nitrite added to meats is probably insufficient for this to be a major anti-oxidant mechanism.     

IDENTIFICATION OF MILK FROM GOAT, EWE AND COW IN THEIR MIXTURES BY POLYACRYLAMIDE GEL ELECTROPHORESIS

A rapid identification of milk from goat, ewe and cow was done in the raw milk mixtures by polyacrylamide gel electrophoresis method. Two kinds of milk were mixed in the following proportions: 75:25%, 50:50%, 25:75% (V/V). Raw goat milk was adulterated with increasing proportions of cow milk or ewe milk, and ewe milk was adulterated with cow milk. Ewe milk in goat milk was detected by the electrophoretic resolution of the casein fraction whereas cow milk in goat and in ewe milk was identified by the presence of two fast-moving whey proteins.