Evolution of some physicochemical and antioxidant properties of black garlic whole bulbs and peeled cloves

Black garlic was processed at three different temperatures of heat treatment (72°, 75° and 78 °C) and close to 90% of relative humidity. Two types of material source were used: whole bulbs and peeled cloves. Total soluble solids content (°Brix), pH, water activity (aw), browning intensive (L value), total polyphenol content, antioxidant capacity and total polyphenol index of the raw and heated garlic were determined. This study showed the changes occurring in the physicochemical and antioxidant properties of the garlic during the heat-treatment evolution. The soluble solids content (°Brix) in garlic increased gradually and the pH decreased in whole bulbs and peeled garlics. The polyphenol content measured by the Folin-Ciocalteu method showed a significant increase during the heat-treatment in all the cases. Also, the antioxidant capacity measured by the ABTS radical increased significantly during the heat-treatment.