The effect of boiling and baking on total phenolic substance amount, phenolic composition and antioxidant capacities of Osmanoğlu and Sariaşlama chestnuts grown in Bursa province

Chestnut contains vitamins, minerals, amino acids and phenolic compounds with antioxidant properties.The nutritional value of chestnut may vary depending chestnuts type, environmental conditions in which it is grown.Processing technologies can also cause changes in nutritional value.The chemical properties of chestnut are also very variable when we look at the literature data. It has been determined by studies that phenolic components vary according to environmental and growth conditions and protein content of chestnut is changed according to the type of soil. This study was carried out to investigate the effect of heat treatment on some physical and chemical properties, total phenolic substance amounts and compositions and antioxidant capacities of Osmanoglu and Sarıaşma chestnuts grown in Bursa province. Total amount of phenolic sustance Folin-Ciocalteu method, antioxidant capacity by DPPH. radical scavenging activity, phenolic compound compositions were determined using the HPLC method. Some of the physical and biochemical properties of raw chestnuts fruit were investigated and as a result humidity % 48.78 - 56.57, ash 1.11-1.27 g 100 g-1, water activity 0.705-0.844, pH 7.03-7.29, color L⃰ 60.52; a⃰ 0.13; b⃰ 12.39 was found to be.The total amount of phenolic substance was 129.17±6.23 in raw chestnut, 180.97±18.25 in boiled chestnut and 149.86±7.95 mmol GAE kg-1 in oven chestnut. The antioxidant capacity determined by DPPH method was found as 0.42±0.01 in raw chestnut, 0.31±0.03 in boiled chestnut and 0.40±0.01 μmol ascorbic acid equivalent g-1 in fried chestnut. According to the DPPH method, the firing process caused a significant decrease in the antioxidant capacity, but the firing process did not cause any change. The total amount of phenol was found to increase significantly with boiling and firing.