Publications by authors named "Dilek Heperkan"

Weissella confusa is a commonly found species in boza, a highly viscous beverage obtained from fermented cereals. Exopolysaccharide (EPS) produced by Weissella confusa C19 was characterized and the role of different cereals on its rheological characteristics were studied. Thus, the effect of the type of cereals on textural characteristics of boza for standard boza production and the fate of W.

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The aim of this study was to investigate the potential use of FTIR spectroscopy as a rapid screening method to detect fumonisin produced by Aspergillus niger. A. niger spore suspensions isolated from raisins were inoculated in Petri dishes prepared with sultana raisin or black raisin extracts containing agar and malt extract agar (MEA).

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The objective of this study was to develop a predictive model for the inactivation of Salmonella spp. in ground beef jerky as a function of temperature (T), pH, potassium sorbate (PS), and final water activity (aw). Following a central composite design, ground beef was combined with PS (0 to 0.

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Shalgam juice, hardaliye, boza, ayran (yoghurt drink) and kefir are the most known traditional Turkish fermented non-alcoholic beverages. The first three are obtained from vegetables, fruits and cereals, and the last two ones are made of milk. Shalgam juice, hardaliye and ayran are produced by lactic acid fermentation.

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Fermentation is one of the oldest methods for preserving of olives applied worldwide for thousands of years. However, olive processing is a speculative area where whether olives are fermented products or pickled products produced by organic acids and salt. Although lactobacilli and yeasts play a major role in the process, literature survey indicates that lactobacilli are less relevant at least in some types of natural green olives during fermentation.

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Ochratoxin A (OTA) contamination in dried figs was investigated using high performance liquid chromatography (HPLC) with fluorescence detection after extraction with methanol and orthophosphoric acid and clean up by an immunoaffinity column. The limit of detection for OTA was 0.12 microg kg(-1).

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Level of mold contamination and mycoflora were determined for 144 mixed feed and feed ingredients, including corn, sunflower cake, soja cake, meat and bone meal, and fish meal. Four samples were found to be free of mold. Among the feed samples examined, the mold count has been found to be low (10 to 10 colonies/g) for fish meal, high (10 to 10 colonies/g) for meat-bone meal and sunflower cake, and extremely high (more than 10 colonies/g) for soja cake, corn and mixed feed.

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