Uso de Kluyveromyces lactis e Torulaspora delbrueckii com adição de café verde para produção de cervejas IPA

Abstract

The increasing demand for specialty beers with distinctive sensory characteristics and higher added value has driven research into new biotechnological strategies, including the investigation of non-conventional yeasts and ingredients rich in bioactive compounds. In this context, the present study aimed to evaluate the potential of Kluyveromyces lactis and Torulaspora delbrueckii, used in single and mixed fermentations, combined with the addition of green coffee in the production of India Pale Ale (IPA) beers. Three fermentation treatments were evaluated: B10 (K. lactis), B14 (T. delbrueckii), and co-fermentation (B10+B14). During fermentation and maturation, physicochemical parameters, microbiological, bioactive compounds, antioxidant activity, volatile organic compounds, and sensory characteristics were evaluated. Chemical characterization was performed using high-performance liquid chromatography with diode array detection (HPLC-DAD) and gas chromatography–mass spectrometry (GC-MS), while sensory evaluation included a hedonic test, Check-All-That-Apply (CATA) analysis, and a focus group. The results showed that K. lactis exhibited higher fermentative performance and achieved the highest overall consumer acceptance (6.57 points), whereas T. delbrueckii showed the highest chlorogenic acid retention and antioxidant activity determined by the ABTS assay (28.85 µmol Trolox equivalents/100 mL), demonstrating remarkable functional potential. Co-fermentation resulted in greater aromatic complexity, characterized by the predominance of esters and terpenes associated with fruity, citrus, and floral notes. Furthermore, the agreement between instrumental analyses and sensory evaluation demonstrated a direct relationship between the chemical composition and consumers' sensory perception. The results demonstrate that the use of non-conventional yeasts associated with green coffee represents a promising strategy for developing innovative IPA beers with improved sensory quality, functional potential, and added value, expanding the prospects for biotechnology applications in the brewing industry.