This research reports on the studied effect of the intensity of ultrasound (24 kHz) on the quality characteristics of olive oil, sesame oil, sunflower seed oil, and tallow olein. These characteristics (free acidity, peroxide value, conjugated dienes concentration, viscosity, iodine value, turbidity, color values, and melting behavior) were determined in oil samples before and after ultrasonic treatment. Changes in the oxidation parameters showed that the highintensity ultrasound treatment accelerated the deterioration of oils. In most cases, extra-virgin sesame oil was most resistant to deterioration from sonicating treatments. The decreases in β-carotene content and Hunter values revealed that ultrasound might have good potential for bleaching oils at an appropriate intensity and frequency. The differential scanning calorimeter thermograms, viscosity, and turbidity results indicated that ultrasound probably accelerates the polymerization of the oils. The present study has confirmed that some changes in the physicochemical parameters or structures of oil components had occurred. These changes depended on the sources and initial conditions of the oils as well as the intensity of the applied ultrasound.

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The study of anthocyanin and phenolic acids has always received much attention due to their extensive range of colors and potential benefi cial health effects. In this study extraction of anthocyanins from barberry, eggplant peel and red cabbage was investigated by using different organic solvents. Soluble solid content, antioxidant capacity, total monomeric anthocyanins and total phenolic content were determined and then degradation kinetics of anthocyanin in different solution during freezing process was assayed. In order to examine the effect of different acids on the degree of extraction of anthocyanin and total phenol, varied concentration of hydrochloric, citric and acetic acids were dissolved in a mixture of water and ethanol to prepare acidifi ed aqueous solution. Results indicated that citric acid solution is one of the best solvents for phenolic and anthocyanin extraction which showed the best scavenging activity of DPPH radical. Results from degradation kinetics of total monomeric anthocyanins revealed that stability of anthocyanins in the solution depended on temperature and other ingredients which are present in the medium. Moreover, the present data confi rmed that barberry and red cabbage acidifi ed extracts could be one of the more stable natural food colorants based on anthocyanins.

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Twenty seven Iranian olive oil samples were collected from different provinces to evaluate fatty acids and sterol compositions. The samples were collected from different geographical locations that varied in altitude, temperature, humidity and rain fall. The sample collected from the northern part of Iran by the Caspian Sea had higher oleic acid [G 2 sample (75.98%)] and lower linoleic acid [Go 5 sample (6.5%)] and palmitic acid [G 2 sample (10.78%)] concentrations than samples from the southern part of the country such as F 1 whose contents of C16:0, C18:1 and C18:2 were 15.27, 62.73 and 16.09%, respectively, in the southern part, the climate is dry and the temperature variation is wider and the elevation is 1,488 m. The results indicated that oleic acid was the predominant fatty acid with 62.7% for F 1 sample in the warmer climate at the south of Iran to 76.0% for G 2 sample in the cooler climate in the north of Iran. According to the results, the highest content of b-sitosterol was 87% related to samples G 9 and Z 3 from the north of Iran and the lowest content was 69.95% related to sample F 1-24 from the south of Iran. Clustering techniques such as principal component analysis and hierarchical cluster analysis were carried out on olive composition data to show similarities and discrimination between samples as a function of the cultivation zone. The two methods applied clearly showed the effect of growing regions on the distribution of the olive oil samples in the high dimensional space created by fatty acid and sterol compositions.

Deep fat frying is a method of food preparation which has been popular for quite a number of years. During deep frying, the quality of oil and the finished product decreases as the result of heat treatment of the oil exposed to air at high temperature. Application of heat by microwave as an alternative to the conventional method of frying has become popular in recent years. In this research, the effects of microwave frying on the changes in the quality indices of used oil have been investigated. To achieve this, potato slices were fried in both frying and sunflower oils by application of medium power microwave (550 W) for 20 min, three times a day, for five consecutive days, and oils were sampled for analysis. The results obtained from the chemical tests demonstrated that used frying oil had lower polar compounds, a higher induction period, and more saturated fatty acids than sunflower oil. The interesting point observed was that peroxides formed as the result of oxidation chain reactions were not broken down and were built up due to the lower temperature and shorter period of frying. Therefore microwave frying might be considered as a suitable alternative to the conventional frying due to less degradation of the oil and consequently a lower production of artifacts.

For evaluation of the authenticity of Iranian olive oil, samples from many Iranian olive oil producers especially north of Iran in the production year 2007 were collected. The fatty acid and triacylglycerol compositions were measured. The most recent calculation methods including DECN the difference between the actual and theoretical ECN42 (equivalent carbon number), triglyceride content and R of olive oils according to IOOC methods were applied. On the basis of our results, we were able to classify the olive oils into the extra virgin, virgin olive and olive oil categories. The important fatty acids are oleic, palmitic and linoleic acids and their main triacylglycerols are OOO, POO, OOL, PLO, SOS plus POP, and OLL, respectively. On the basis of the triacylglycerol results, experimental ECN48, ECN46, ECN50, ECN44 and ECN42 were obtained. By using the fatty acids results and a computer program, the theoretical ECN42 and ECN44 were calculated. Then R values, being the ratio of r ECN42/r ECN44 for authenticity of all olive oils and DECN for determining categories of olive oils, were defined. The results of olive oil samples were in the accepted limits of Codex and IOOC. Finally we suggest that the R and DECN can be used in identification of adulteration of olive oils and also they are useful from the point of view of authenticity and classification.

This study aims to extract oil from fresh sour cherry kernel (Cerasus vulgaris Miller) using the cold press method. The oil content and moisture were obtained as 31.89% and 4%, respectively. The organoleptic assessment of the oil was acceptable and the free fatty acid value was obtained as 1.36 (mg KOH/g oil). In addition, peroxide value and anisidine index of sour cherry kernel oil were obtained as 0.99 meqO2/kg oil and 0.15, respectively. The predominant fatty acids were linoleic acid (42.34%), oleic acid (35.45%), α-eleostearic acid (9.34%), and palmitic acid (6.54%), respectively. The kernel oil contained nine major triacylglycerols consisting of OLL (20.44%), OOL (16.99%), LLL (8.20%), LLEl (7.28%), PLO (7.24%), OElO (5.03%), OOO (4.70%), ElLO (4.54%), PLL (4.35%), and POO (3%), respectively. The most abundant sterol compounds were β-sitosterol (83.55%), ∆5-avenasterol (6.8%), sitostanol (4.8%), campesterol (3.5%), and stigmasterol (0.53%), respectively. Also, antioxidant activity, total phenol content (TPC), total anthocyanin content (TAC), total flavonoid content (TFC), total tannin content (TTC), and total tocopherol content were obtained as 73.22%, 33.44 mg GA/g dry matter, 177.84 mg/L, 46.37 mg/g dry matter, and 1.21 mg GA/g dry matter, 832.5 mg/kg oil, respectively. The amount of amygdalin in the oil sample was not detectable.