Some physical and chemical characteristics of Taskopru and Chinese black garlics

Abstract

Black garlic, also called aged garlic, is a type of fermented garlic used as a food ingredient in Asian cuisine. It's made by fermenting whole bulbs of garlic at high temperature. The purpose of this study was to evaluate suitability of Taskopru and Chinese garlic for black garlic manufacture and determine the antioxidant properties of these products. Taskopru and Chinese garlic were harvested at 2014 in Taskopru (Kastamonu, Turkey). They were kept to produce black garlic at 60 degrees C and 70-90% relative humidity for 45 days. In this study, the color, dry matter, pH, penetration resistance, total phenolics and ferric reducing antioxidant power (FRAP) values of both raw and black garlics were recorded. The L*, a*, b*, dry matter, pH, total phenolics and FRAP values in Taskopru raw garlics were found as 70.71 +/- 2.80, -0.77 +/- 0.21, +23.77 +/- 0.55, 35.09 +/- 0.08%, 6.38 +/- 0.02, 294.73 +/- 11.61 mg GAE kg(-1) and 640.76 +/- 86.98 mu mol Fe2+ g(-1), respectively, while these values in Taskopru black garlic were found as 29.53 +/- 1.45, +1.18 +/- 0.12, +1.83 +/- 0.21, 86.52 +/- 0.52%, 4.89 +/- 0.03, 308.77 +/- 30.65 mg GAE kg(-1) and 2266.75 +/- 417.62 mu mol Fe2+ g(-1), respectively. The parameters in Chinese raw garlics were found as 70.34 +/- 1.09,-0.30 +/- 0.05, +24.06 +/- 0.13, 36.73 +/- 0.46%, 6.43 +/- 0.03, 359.81 +/- 2.85 mg kg(-1) and 678.20 +/- 77.56 mu mol Fe2+ g(-1), respectively, while these values in Chinese black garlics were found as 28.86 +/- 0.73, +1.43 +/- 0.26, +1.97 +/- 0.35, 83.67 +/- 0.76%, 4.64 +/- 0.10, 424.49 +/- 100.37 mg GAE kg(-1) and 2304.18 +/- 162.21 mu mol Fe2+ g(-1), respectively. The penetration resistance of the cloves were measured by Texture Analyzer, and the results were found as 31.29 +/- 4.42 N in Taskopru raw garlics, 22.57 +/- 11.07 N in Taskopru black garlics, 21.03 +/- 3.90 N in Chinese raw garlics and 17.46 +/- 15.04 N in Chinese black garlics. Generally, the antioxidant power and total phenolic contents of Chinese black garlic were higher than the values of Taskopru black garlic, but it wasn't statistically significant (P>0.05). There was no difference between the other parameters except dry matter and pH values of Taskopru and Chinese black garlics (P>0.05).