33F-6 |
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C. ALASALVAR1, M. A. Farsi1, and F. Shahidi2. (1) Food Research Center, Univ. of Lincoln, Dept. of Biological Sciences, Brayford Pool, Lincoln, LN6 7TS, United Kingdom, (2) Dept. of Biochemistry, Memorial Univ. of Newfoundland, 300 Prince Philip Dr., Saint John's, NF A1B 3X9, Canada Cherry laurel (Laurocerasus officinalis Roem.) is a popular fruit in the Black Sea region of Turkey. The fruits and seeds of cherry laurel are well-known as herbal medicine in Turkey and have been used for many years for the treatment of stomach ulcers, digestive complaints, bronchitis, eczema, haemorrhoids and diuretic, among others. Pekmez (concentrated juice by heating), which is made from sugar rich fruits such as cherry laurel, is a traditional Turkish product. Little is known about nutraceutical components of cherry laurel and that of indigenous cherry laurel pekmez. The objective of this research was to compare the antioxidant activity, the contents of anthocyanins, phenolics and carotenoids of two native fresh cherry laurel varieties and pekmez. Two fresh cherry laurel varieties (namely kiraz and findik) and pekmez were procured from the Giresun province of Turkey. An improved method of oxygen radical absorbance capacity (ORAC) assay was used to measure the antioxidant activity, using a spectrofluophotometer. Total anthocyanins were determined by a pH-differential method, using spectrophotometic means. Total phenolics and phenolic acids were determined colorimetrically using Folin-Ciocalteu reagent and by HPLC, respectively. Total carotenoids were measured colorimetrically, using a spectrophotometer. A linear correlation existed between ORAC and total phenolics (R2=0.99). The mean total content of phenolics and anthocyanins in kiraz, findik and pekmez were 454, 651 and 1444 mg/100 g of fresh weight expressed as ferulic acid equivalents and 123.8, 174.3 and 9.3 mg of cyanidin 3-glucoside equivalents/100 g of fresh weight, respectively. The corresponding carotenoid contents in the samples were 254, 261.3 and 114 mg/100 g of fresh weight, respectively. A significant amount of anthocyanins and carotenoids was lost during heat processing of pekmez. Eight phenolic acids were identified and quantified, among which p-hydroxybenzoic, caffeic and vanillic acids were predominant in a decreasing order. These results suggest that cherry laurel and its product pekmez serve as good sources of natural antioxidants.
Session 33F, Nutraceuticals & Functional Foods: Antioxidants and phytochemical analysis
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