Impact of elderberry enrichment on beers: Effects of addition stage, pasteurization, filtration, production scale, and ageing on anthocyanin content, bioactivity, and sensory properties

In this study, innovative beers were developed by incorporating elderberries as a source of bioactive compounds in two styles: Blonde Ale and Catharina Sour. The impact of elderberry addition at different brewing stages, filtration, pasteurization, production scale, and ageing on anthocyanin content (cyanidin-3-O-sambubioside-5-O-glucoside, cyanidin-3,5-O-diglucoside, cyanidin-3-O-sambubioside, and cyanidin-3-O-glucoside), sensory properties, and bioactivity (antiproliferative effect on Caco-2 colorectal adenocarcinoma cells) was evaluated. The addition of elderberries significantly changed the beer’s colour, specific gravities, and bitterness. Elderberries increased colour intensity, especially when added at the maturation stage. Anthocyanin quantification revealed higher concentrations, above 10 mg/L of cyanidin-3-O-sambubioside-5-O-glucoside and cyanidin-3-O-sambubioside, in beers with elderberries added during maturation. Sensory analysis showed enhanced red colour, turbidity, and red fruit aroma, with a higher appreciation for beers with elderberries added during maturation. Bioactivity tests demonstrated that elderberry addition during maturation significantly increased the antiproliferative activity against human colorectal adenocarcinoma Caco-2 cells. The percentage of cell growth reduced from 68.0 ± 6.0 % to 49.2 ± 8.4 % when the cells were cultured with dilutions of beers without and with fruit addition, respectively. With the effect persisting after pasteurization. Principal Component Analysis (PCA) and Agglomerative Hierarchical Clustering (AHC) linked higher antiproliferative activity to specific anthocyanins in the present conditions. Scale-up to an industrial craft beer scale (500 L) confirmed the trends observed on the laboratory scale, with some variations in anthocyanin content. The industrial-scale beers maintained their antiproliferative activity, reinforcing the potential of elderberry-enriched beers as functional beverages.