Dados do Trabalho

Título

ADDITION OF FEIJOA (Acca sellowiana) PULP TO GREEN TEA KOMBUCHA AND ITS EFFECT ON PHENOLIC COMPOUNDS AND ANTIOXIDANT ACTIVITY

Introdução

Kombucha is a beverage that stands out for its composition, which is rich in bioactive compounds; flavoring it with fruit pulp such as feijoa (Acca sellowiana) can enrich this composition and enhance the value of native Brazilian fruits. This study aimed to investigate the effect of adding feijoa pulp in the kombucha flavoring stage, evaluating the parameters of total phenolic compounds (TPC) and in vitro antioxidant activity of the prepared beverages.

Material e Métodos

The kombucha was prepared by infusing green tea (Camellia sinensis) at 1.25% (w/v) in boiling water for 15 minutes, followed by the addition of 5% (w/v) sucrose and 10% (v/v) of inoculum. Fermentation took place at 25ºC for 7 days until pH 2.93 ± 0.02. Afterward, flavoring was carried out, adding 10% (v/v) feijoa pulp, followed by incubation for 72 hours at 25ºC, ending with a pH of 3.03 ± 0.01. TPC analysis was carried out using the Folin-Ciocalteu method, and antioxidant activity was assessed using the ABTS+• radical inhibition assay and the FRAP (ferric reducing antioxidant power) assay.

Resultados e Discussão

The unflavored kombucha had a significantly (p<0.05) higher TPC content (214.25 ± 3.82 mg of gallic acid equivalent GAE/100mL) than the green tea infusion (180.36 ± 2.10 (GAE)/100mL). The addition of feijoa pulp resulted in a significant increase (p<0.05) of ≈19% in the TPC content (255.64 ± 6.74 mg AGE/100mL) of the kombucha. Fermenting the infusion also led to a significant (p<0.05) increase in antioxidant activity by the ABTS+• assay, from 28.46 ± 0.35 to 34.89 ± 0.78 μM Trolox/mL. However, after flavoring, no significant difference was observed for this parameter (35.13 ± 0.66 μM Trolox/mL). On the other hand, the FRAP method showed that the addition of feijoa in the flavoring resulted in a significant effect (p<0.05), increasing from 4.01 ± 0.07 μM Trolox/mL in the infusion to 4.80 ± 0.04 μM Trolox/mL in the kombucha and 4.97 ± 0.05 μM Trolox/mL after flavoring.

Conclusão

Given the above, it can be concluded that adding feijoa pulp can contribute to the bioactive composition of kombuchas and diversify the flavors of this beverage.