AROMATIC PROFILE ANALYSIS OF COMMERCIAL KOMBUCHA FLAVORED WITH GINGER

Kombucha is an ancient beverage traditionally produced from an infusion of Camellia sinensis leaves, commonly black or green tea, sweetened with sucrose or another carbon source, and acidified by inoculating a symbiotic culture of bacteria and yeasts (SCOBY). During the fermentation stage, the microorganisms present in the SCOBY convert the substrates added to the tea into different chemical compounds and secondary products, such as organic acids, terpenes, esters, among others. Many of these compounds are responsible for the aromatic profile and the characteristic flavor of the beverage. Based on this premise, the present study aimed to characterize the profile of volatile compounds (VCs) in commercial kombucha flavored with ginger. The VCs were extracted by solid-phase microextraction (SPME) using an 85 µm CAR-PDMS fiber for 30 minutes, followed by desorption in the GC-MS injector (Shimadzu Q2010 Ultra) at 250 °C. The separation of VCs was performed on an HP-5MS column using helium as carrier gas, and 2-octanol as the internal standard. Compound identification was carried out by comparison with the NIST 2005, NIST 2008, NIST 2021, and WILEY 2008 libraries. To ensure accurate compound identification, the Kovats Retention Index (IRKovats) was calculated from a standard mixture of n-alkanes, considering the agreement between experimental and reference values. A total of 40 volatile compounds were identified, distributed among different chemical groups: terpenes (50%), alcohols (15%), esters (15%), ketones (7.5%), aromatic hydrocarbons (5%), aldehydes (2.5%), carboxylic acids (2.5%), and ethers (2.5%). The terpene class was predominant (20 VCs). The major components, based on the relative peak area percentage above 1%, were: citronellol (≈6.57%), which imparts a floral odor with citrus and rose notes; geraniol (≈6.20%), also contributing to floral and citrus aromas; linalool (≈2.58%), associated with the fruity aroma of the beverage; ethyl octanoate (≈1.49%), responsible for the fruity and alcoholic aromatic profile; and eucalyptol (≈1.13%), which contributes to the herbal and refreshing aroma characteristic of this fermented beverage flavored with ginger. The predominance of terpenes highlights the strong influence of plant-based ingredients on the beverage’s aroma, and the presence of oxygenated monoterpenes (such as citronellol, geraniol, and linalool), together with ethyl octanoate and eucalyptol, indicates the interaction between the bioactive and fermentative compounds of ginger in shaping the aromatic profile.