Comparison of the Physicochemical Properties and Antioxidant Activity of Decaffeinated Coffee Capsules

In this study, 10 types of domestically and internationally available decaffeinated coffee capsules were compared and analyzed to evaluate the differences in the quality and activity of each product.The samples were extracted as 40 mL espressos using a capsule coffee machine under the same conditions, and the physicochemical properties, including color, total dissolved solids, and pH, were measured.Additionally, antioxidant activities were assessed by evaluating the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging abilities, and the total phenol and flavonoid contents were determined.The analysis revealed that the DPPH radical scavenging ability ranged from 49.880.62% to 60.621.50%,and the ABTS radical scavenging ability ranged from 63.541.97% to 89.481.12%,showing significant variation among the samples.Caffeine content varied from 0.09 mg/mL to 0.18 mg/mL, indicating considerable differences in product quality despite the same decaffeinated labeling.Moreover, a strong positive correlation between the flavonoid and total phenol content was observed (r=0.95), while a negative correlation was found between DPPH radical scavenging activity and pH (r=-0.87).These findings suggest that differences in the quality and activity of decaffeinated coffee capsules exist between products, which could significantly influence consumer choice.