EFFECT OF FRUIT JUICES ON TOTAL PHENOLIC CONTENT AND FLAVONOID CONTENT OF BEER

In this study, a pale ale beer had been enriched with the juices of 10 fruits in different concentrations. The first enrichment was carried out before primary fermentation. Then, before bottling, another dose of juice (in 3 different concentrations) had also been added to the previously enriched batches and the control sample too, therefore 7 different samples were produced by each fruit, besides the control sample. Total phenolic content (TPC) and flavonoid content of the samples were determined by spectrophotometric methods, and statistical analysis including one-way ANOVA was also performed. Based on our results, strawberry, cherry and sour cherry juices are the richest in the analysed components – they showed outstanding results compared to the other juices. However, these results did not cause the increase of these parameters in every case. Total phenolic content of the flavoured beers was similar or lower than the control sample’s result. On the other hand, flavonoid content of the beers enriched with cherry juice increased significantly, and the addition of strawberry and sour cherry juice was also efficient. Every flavored sample showed higher flavonoid content than the control samples, and the double enrichment with strawberry, cherry and sour cherry juice had the most significant impact. In case of phenolic compounds, the juice addition was more efficient before bottling than before primary fermentation. Besides the potential health benefits, the addition of different fruit juices may also increase the popularity of these beverages, which might result in a wider range of products and consumers.