Şensu, Eda; Altuntaş, Ümit; Gültekin-Özgüven, Mine; Duran, Ayhan; Özçelik, Beraat; Yücetepe, Aysun

The original version of this article unfortunately contained error in co-author’s affiliation. The affiliation of author Ümit Altuntaş were incorrectly given as Department of Food Engineering, Faculty of Chemical and Metallurgical Engineering, Istanbul Technical University, Maslak, Istanbul TR-34469, Turkey but should have been Department of Food Engineering, Gümüşhane University, Gümüşhane, Turkey. The original article has been corrected.

Altuntaş, Ümit; Güzel, İsmail; Özçelik, Beraat

This study aimed to evaluate the biochemical composition and biological activity of propolis samples from different regions of Türkiye to characterize and classify 24 Anatolian propolis samples according to their geographical origin. Chemometric techniques, namely, principal component analysis (PCA) and a hierarchical clustering algorithm (HCA), were applied for the first time to all data, including antioxidant capacity, individual phenolic constituents, and the antimicrobial activity of propolis to reveal the possible clustering of Anatolian propolis samples according to their geographical origin. As a result, the total phenolic content (TPC) of the propolis samples varied from 16.73 to 125.83 mg gallic acid equivalent per gram (GAE/g) sample, while the number of total flavonoids varied from 57.98 to 327.38 mg quercetin equivalent per gram (QE/g) sample. The identified constituents of propolis were phenolic/aromatic acids (chlorogenic acid, caffeic acid, p-coumaric acid, ferulic acid, and trans-cinnamic acid), phenolic aldehyde (vanillin), and flavonoids (pinocembrin, kaempferol, pinobanksin, and apigenin). This study has shown that the application of the PCA chemometric method to the biochemical composition and biological activity of propolis allows for the successful clustering of Anatolian propolis samples from different regions of Türkiye, except for samples from the Black Sea region.

Özçelik, Beraat; İlyasoğlu, Huri

Cultivar and geographical characterization of olive oil have been gained importance since it is related to botanic and geographic origin. Memecik oil is one of the economically important olive oil in our country. In this study, quality parameters, fatty acid, triacylglycerol and sterol composition, α-tocopherol and total phenol content, phenolic profile and aroma profile of Memecik oils were determined. Quality parameters, fatty acid and sterol composition (except campesterol) of Memecik oils agreed with the Turkish Food Codex. Oleic acid (% 73.37-75.64), palmitic acid (% 11.45-13.84) and linoleic acid (% 7.33-8.91) were the major fatty acids found in Memecik oils. Triolein (% 63.50-68.32), palmitodiolein (% 18.25-25.82) and dioleolinolein (% 6.01-9.18) were the major triacyglycerols detected in the studied samples. The sterol composition of Memecik oils consisted of mainly b-sitosterol (% 80.76-83.00), D5-avenasterol (% 11.02-12.78) and campesterol (% 4.01-4.97). Hydroxytyrosol, tyrosol, ferulic acid, p-coumaric acid, apigenin, and luteolin in phenolic profile and hexanal, hexanol, E-2-hexenal, E-2-hexenol, Z-3-hexenol in aroma profile were detected in Memecik oils.

Ilyasoǧlu, Huri; Temel, Sara; Özçelik, Beraat

This study presents the results of a survey regarding consumer perceptions of organic foods in Turkey. The survey was conducted to determine consumer attitudes towards organic foods and the reasons for consumption or non-consumption of organic foods. A total of 383 consumers from different occupational groups living in Istanbul participated in the research. The results of the survey revealed that more than half of the survey participants had knowledge about organic foods. The majority of the participants were positive towards organic foods and purchased them as well. The results of chi-square analysis showed that the consumption of organic foods varied with respect to gender, job and education. Women and more educated participants tend to buy organic foods more than other participants. In market, fruits and vegetables, cereals and legumes, dried fruits and dairy products were organic products recognized by consumers. The main organic products purchased by consumers were fruits and vegetables. The results of the survey also indicated that the participants confidence in organic foods was at moderate level. About 37% of the participants was found to rely on organic foods and about 49% of the participants were unsure about organic foods. Organic foods were purchased because they were perceived as healthy, environmentally friendly and more nutritious than conventional foods. However, the consumption of organic foods was found to be lower. The majority of the participants stated that they consumed organic foods rarely or sometimes. Price and lack of availability of organic foods were barriers to increase the consumption of organic foods.