Hasan Yalcin

Effect of γ-Irradiation on Bioactivity, Fatty Acid Compositions and Volatile Compounds of Clary Sage Seed (Salvia sclarea L.)

UNLABELLED Clary sage seeds (Salvia sclarea L.) were obtained from plants cultivated, and 2.5, 4.0, 5.5, and 7.0 kGy doses of γ-irradiation were applied to the clary sage seeds. They were then analyzed for their protein, ash, oil and dry matter contents, and fatty acid composition. Additionally, the total phenolic contents, antiradical, antioxidant activities, and volatile compounds of the clary sage seed extract were determined. There was no significant difference in protein content. However, the moisture, oil, and ash contents of the samples were affected by irradiation. While the 7 kGy dose had a positive effect on the total phenolic content and antiradical activity of the sage seed extract, all doses have negative effects on the antioxidant activity of the sage seed. The main fatty acid of the sage seed was remarkably found as α-linolenic acid. The four irradiation levels caused significant differences in fatty acid composition by affecting all fatty acids except palmitic, palmitoleic, and eicosenoic acids. The dominant volatile compounds of control sage seed were found as β-pinene (18.81%) and limonene (15.60%). Higher doses of the irradiation decreased volatile components of sage seed. Clary sage seed including high omega-3 can be irradiated with low doses (≤ 2.5 kGy) of γ-irradiation. PRACTICAL APPLICATION Clary sage is one of the most popular Salvia species in Turkey and many countries. Clary sage seed has approximately 29% oil content and this oil contains >50% of α-linolenic acid. γ-Irradiation is widely applied in the preservation of spice quality. The present study shows that the antioxidant activity of the clary sage seed is decreased by γ-irradiation. Additionally, higher doses of irradiation also decreased the volatile components of sage seed. Therefore, we suggest that clary sage seed which includes high levels of omega-3 should be irradiated with low doses (≤ 2.5 kGy) of γ-irradiation.

The Enrichment of Hen Eggs with ω-3 Fatty Acids

A study was conducted to determine the omega-3 fatty acid compositions of enriched eggs obtained from hens by feeding flaxseed and fish oil. Laying hens were fed a diet containing fish oil (FOD) (1.5%) or a mixture of flaxseed (10%) and fish oil (FFOD) (1.5%) for 15 and 30 days. Another group was fed commercial diet as a control. Eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA) were not determined in the control groups eggs. However, the EPA level was 0.87% and 0.82% in the FOD groups eggs and 0.49% and 0.55% in the FFOD groups eggs, obtained after a 15- and 30-day feeding period, respectively. Corresponding values for DPA were 0.45% and 0.50% in the FOD groups eggs and 0.41% and 0.44% in the FFOD groups eggs. Docosahexaenoic acid contents of eggs obtained from the FOD group were 4.85% and 4.92% after a 15- and 30-day feeding period, respectively, compared with 3.29% and 3.91% in the FFOD groups eggs and 1.03% in the control groups eggs. The alpha-linolenic acid content of eggs was 0.45% and 0.49% in the FOD groups eggs after a 15- and 30-day feeding period, respectively, and 0.43% in the control groups eggs, whereas it was 3.61% and 4.10%, respectively, in the FFOD groups eggs.

Comparison of adaptive neuro-fuzzy inference system and artificial neural networks for estimation of oxidation parameters of sunflower oil added with some natural byproduct extracts

BACKGROUND Apple pomace, orange peel and potato peel, which have important antioxidative compounds in their structures, are byproducts obtained from fruit or vegetable processing. Use of vegetable extracts is popular and a common technique in the preservation of vegetable oils. Utilization of apple pomace, orange peel and potato peel extracts as natural antioxidant agents in refined sunflower oil during storage in order to reduce or retard oxidation was investigated. All byproduct extracts were added at 3000 ppm to sunflower oil and different nonlinear models were constructed for the estimation of oxidation parameters. RESULTS Peroxide values of sunflower oil samples containing different natural extracts were found to be lower compared to control sample. Adaptive neuro-fuzzy inference system (ANFIS) and artificial neural networks (ANN) were used for the construction of models that could predict the oxidation parameters and were compared to multiple linear regression (MLR) for the determination of the best model with high accuracy. It was shown that the ANFIS model with high coefficient of determination (R(2) = 0.999) performed better compared to ANN (R(2) = 0.899) and MLR (R(2) = 0.636) for the prediction of oxidation parameters CONCLUSION Incorporation of different natural byproduct extracts into sunflower oil provided an important retardation in oxidation during storage. Effective predictive models were constructed for the estimation of oxidation parameters using ANFIS and ANN modeling techniques. These models can be used to predict oxidative parameter values.

Effect of gamma-irradiation on some chemical characteristics and volatile content of linseed.

The effect of irradiation (2.5, 4.0, 5.5, and 7.0 kGy) on chemical properties and volatile contents of linseed was investigated. Consistent decreases were observed in both protein and oil content of the irradiated linseed samples with increasing irradiation doses. The ash content of the irradiated linseed samples increased significantly (P<.05) with increasing irradiation doses except for 5.5 kGy. Irradiation treatment caused irregular changes in palmitic and stearic acid content. Although styrene and p-xylene content decreased as a result of irradiation, 1-hexanol content only decreased at 7.0 kGy. Benzaldehyde, p-cymene, and nonanol were not determined at irradiation doses above 4.0 kGy.

Influence of the harvesting year and fertilizer on the fatty acid composition and some physicochemical properties of linseed (Linum usitatissimum L.)

Sarı 85 (Linum usitatissimum L.) linseed variety was used in this study. Linseed was cultivated at 2008 (LS-08) and 2009 (LS-09) without fertilizer. In addition, at 2009 diammonium phosphate [(NH4)2HPO4] and ammonium nitrate (NH4NO3) were applied (LSF-09). The linseeds were analyzed for protein, ash and oil contents and fatty acid compositions. There were differences among harvesting years for oil, protein and ash contents of the seeds. The greater oil and protein contents were obtained during LS-08 compared with LS-09. There were no significant difference in protein and ash content between LS-09 and LSF-09 while a significant difference was observed in oil content. Seed protein, oil and ash contents were significantly affected by the harvesting year, but only oil content was affected by the fertilizer treatment. There are significant differences in palmitic, stearic, oleic, α-linolenic and arachidic acid between LS-08 and LS-09. While palmitic, stearic, oleic acid decreased, α-linolenic and arachidic acid increased during 2009 harvesting year. LSF-09 has the highest amount of α-linolenic acid. The fertilizing treatment seems to have an increasing effect on the amount of α-linolenic acid, while it has a decreasing effect on the oleic acid content.

Prediction of the antimicrobial activity of walnut (Juglans regia L.) kernel aqueous extracts using artificial neural network and multiple linear regression

The mathematical model was established to determine the diameter of inhibition zone of the walnut extract on the twelve bacterial species. Type of extraction, concentration, and pathogens were taken as input variables. Two models were used with the aim of designing this system. One of them was developed with artificial neural networks (ANN), and the other was formed with multiple linear regression (MLR). Four common training algorithms were used. Levenberg-Marquardt (LM), Bayesian regulation (BR), scaled conjugate gradient (SCG) and resilient back propagation (RP) were investigated, and the algorithms were compared. Root mean squared error and correlation coefficient were evaluated as performance criteria. When these criteria were analyzed, ANN showed high prediction performance, while MLR showed low prediction performance. As a result, it is seen that when the different input values are provided to the system developed with ANN, the most accurate inhibition zone (IZ) estimates were obtained. The results of this study could offer new perspectives, particularly in the field of microbiology, because these could be applied to other type of extraction, concentrations, and pathogens, without resorting to experiments.

Bioactive Compounds of Fruits and Vegetables

Fruits and vegetables are colourful, flavourful and nutritious components of our diets. Bioactive compounds such as polyphenols, carotenoids, vitamins, phytoestrogens, glucosinolates and anthocyanins present in fruits and vegetables are receiving increased attention because of their potential health benefits. Diets rich in fruits and vegetables may help to delay the ageing processes and reduce the risk of certain types of cancer, cardiovascular diseases and other chronic diseases. The combination of vitamins, minerals, phenolic antioxidants and fibre seems to be responsible for these effects. Nowadays, some authors recommend consumption of fruits and vegetables with high bioactivity, because only such fruits and vegetables are effective in prevention and treatment of various diseases.

The effect of harvest time on the bioactive properties and volatile components of lavender (Lavandula officinalis)

This study was designed to determine the effect of harvest time on the bioactive properties and volatile components of flowers, leaves and stems of Lavandula officinalis. The bioactive properties were examined in terms of total phenolic content, antiradical activity and antioxidant capacity by the Folin-Ciocalteu, 1.1-diphenyl-2-picrylhydrazyl scavenging and phosphomolybdenum methods, respectively. Volatile components were detected with gas chromatography-mass spectrometry. Water and methanol were used for extraction solvent and three different parts of the day (morning, midday and evening) were selected for harvest time. Water extracts had higher total phenolic contents (337.2-771.5 mg gallic acid equivalents (GAE)/g dry extract) than methanolic extracts (170.3-320.8 mg GAE/g dry extract), and in general, midday values were less than morning and evening rates and had a significant difference depending on harvest time. A similar feature was observed in respect to antioxidant properties. The inhibition rat...

Effects of pre-drying on the quality of frying oil and potato slices

The effects of pre-drying on the quality of frying oil and potato slices were investigated. Potato slices were air-dried at 60 °C for 15, 30, 45, 60, 90, 120 min before frying. The pre-dried potato slices were deep-fried in sunflower oil at 180 °C for 5, 10, 13 min and sampled. For the oil sampling, the frying procedure was repeated five times using dried potato slices without oil replenishment. Oil samples were removed at the end of successive frying operations (13 min-1st, 39 min-3rd, 65 min-5th) and analysed. The moisture content, colour and oil intake of the potato slices and the colour, peroxide value, free fatty acid, fatty acid composition and viscosity of the oil samples were evaluated. Pre-drying treatment had a significant effect on the physicochemical properties of potato slices and frying oil. Pre-drying decreased the oil absorption. The oil content for the 5 min frying was found as 4.46% and 2.93%, respectively, for the control and 120 min pre dried samples. Free fatty acid levels and viscosi...

Supplemental Fish Oil and its Impact on n− 3 Fatty Acids in Eggs

Abstract Fish oil is a rich source of n− 3 fatty acids, especially eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids. Using fish oil in the diet of hens results in the transfer of these n− 3 fatty acids into the developing egg yolk reducing the proportion of n− 6 fatty acid, as well as the n− 6/ n− 3 ratio. These omega 3–enriched eggs when consumed by humans provide health benefits such as improved cardiovascular and cognitive functions. However, the amount of fish oil that can be added to the hen’s diet is limited because too high of a concentration can lead to a fishy taste or odor in the egg. The effect of hen’s consumption of fish oil–based diets on the n− 3 fatty acid composition, cholesterol content, oxidative stability, and sensory characteristics of enriched eggs as well as the production parameters of hens will be discussed. Human health benefits with regard to consumption of omega 3–enriched eggs derived from hens fed fish oil will also be reviewed.