A study on tarhana production with the addition of various grape fruits

ABSTRACT M.Sc. Thesis A STUDY ON TARHANA PRODUCTION WITH THE ADDITION OF VARIOUS GRAPE FRUITS Emine ŞEMŞİMOĞLU Afyon Kocatepe University Graduate School of Natural and Applied Sciences Department of Food Engineering Supervisor: Prof. Abdullah ÇAĞLAR In this study, blueberries, blackberries and black mulberries were added to tarahana, native to Turkey traditional product, at different ratios (15% and 25%), form of tarhana dough in dry and wet forms were produced. The pH, moisture, ash, acidity, protein, phenolic compounds, viscosity, antioxidant capacity, color values, mineral content and sensory analyzes were determined in wet and dried tarhana. The phenolic contents of tarhana wite blackberries were higher than those added wite blueberries and black mulberries. It was determined that the antioxidant capacities of blueberries and black mulberries were higher than the samples wite blackberries. The addition of blueberry, blackberry or black mulberry to tarhana affected the pH of the samples. The pH of tarhana samples decreased during fermentation. The lowest pH value was found in the tarhanas added with blackberry and the highest pH value was found in the tarhana added with black mulberry. Higher moisture content was detected in the samples supplemented wite blueberry while lower moisture content was found in blackberry added samples. While the highest titration acidity was determined as 20,06% in the samples containing blackberries, the lower titration acidity (12,63%) was found in tarhanas containing black mulberry. The addition of blueberries to tarhana samples increased the phenolic content at the highest level. Blackberries and black mulberries also increased phenolic content. While tarhana samples containing the highest antioxidant capacity (22371,43), control tarhana samples had the lowest antioxidant capacity. Drying process partially reduced the antioxidant capacity of the samples. However, antioxidant capacity of tarhana samples increased as the ratio of supplementation of berry fruits increased. The highest antioxidant capacity was found in wet tarhana samples (YMYT25) containing 25% blackberries. It was found that blueberry samples had higher L * (brightness) and a * (redness) values and black mulberry samples had lower L * and a * values in color measurements. The ratio of grape fruits added to the samples significantly affected the mineral contents of tarhana samples except for manganese and zinc. Magnesium was found to be the most abundant mineral in wet tarhana (BÖYT25) containing 25% blackberry and the lowest in dried control tarhana. Potassium was the highest in dry tarhana containing 25% black mulberry (KDKT25). Macro elements were the highest in dry tarhana containing 25% black mulberry (KDKT25). Panelists gave higher consistency, smell, taste, color, aroma and general appreciation scores to tarhana samples containing blueberries. Tarhana samples containing mulberry had lower sensory evaluation scores than the rest of the samples. Drying process increased the consistency, odor, aroma and general acceptance scores of the samples, but did not have a statistically significant effect on taste and aroma scores. Based on the sensory evaluations, wet and dry control samples (KTKONT and YTKONT) and dry tarhana samples containing 15% and 25% blueberries (YMKT15, YMKT25) were the most preferred. 2019, xiii + 100 pages Keywords: Tarhana, Berry Fruits, Blueberry, Blackberry and Black Mulberry, Phenolic Compounds, Antioxidant Capacity