Optimization of fermented kombucha from black-aged garlic using response surface design and aroma-active compounds identification

Abstract

Kombucha beverage from black-aged garlic was optimized using response surface methodology. The design was developed based on a Box-Behnken design, with black-aged garlic (BAG) (10-20g), sucrose concentration (10–20% w/v) and ratio of SCOBY: BAG (0.5-1.0). The optimal composition consisted of 10.9-15.0g of BAG, 19.3-19.9% w/v and 0.7-1.0 SCOBY ratio, which provided a high level of total phenolic and total flavonoid contents (89.43 mg GAE 100 g-1 and 48.80 mg RE 100 g-1, respectively. Furthermore, GC-O-MS analysis revealed the presence of nine aroma-active compounds, including organosulfur compounds (diallyl trisulfide, allyl methyl trisulfide), alcohols (α-terpineol, amyl alcohols, laevo-borneol, furanoid), an octacosane, a butyric acid, and a phenolic molecule, which were found to be the most abundant. This study demonstrated the development of a functional beverage derived from black-aged garlic, which was achieved through investigating the kombucha process.

Keywords

• Fermented kombucha
• Anti-oxidation
• Black garlic
• Volatile compounds
• Response surface methodology