# Characterization of Beer Produced with the Addition of Brown Macrolgae _Fucus virsoides_
## 3 Results and Discussion  
The results of this research are presented in Tables 1 and 2. Table 1 shows the basic physical-chemical indicators determined in the produced beers. When looking at the basic parameter, such as the specific gravity, it can be noted that wort with the addition of algae had a somewhat higher extract content, 1.02935 mg/L, in comparison to the control sample, which had 1.02495 mg/L. This indicates that alga addition contributed to extract values, due to its content of carbohydrates. This was reflected on the original extract which reached 14.3 \({}^{\circ}\)P in wort with alga addition, as opposed to 12.8 \({}^{\circ}\)P in the control sample. Such high extract content, however, resulted in beer with low alcohol content, \(<\)4% \(v/v\) for both beers. This could be explained by the high levels of unfermentable extract that is unavailable to yeast to conduct fermentation. The pH values are showing statistical difference between samples, meaning that the addition of algae significantly affected the pH value of beer, reducing the acidity by almost 5%. This is a significant change in pH and would affect the sensory properties. Such significant change could be related to a higher alcohol content in beer with the addition of algae (3.80% \(v/v\)) in comparison to the control sample which contained 3.55% \(v/v\). Bitterness did not undergo any changes with the addition of algae, but it was the same for both beers, 42 IBU, meaning that algae do not contribute to bitterness. Color was slightly affected with the addition of algae, and was a bit higher in beer with the addition of _F. virsoides_. This is expected since _F. virsoides_ is a brown alga. Since there are not many data about this topic, it is hard to compare the obtained results with published materials. There are some research studies in which microalgae such as _Arthospira platensis_ (spirulina) or _Tetraselmis chui_ were added into the brew [27; 28], but macroalgae have not yet been described as a potential brewing adjunct, even though they possess health- beneficiary ingredients such as fucoidian and carrageenan [29]. The results of wort in the original extract, in the research conducted by [PERSON] and [PERSON] [27], are in accordance with the data collected in this research. The pH value was higher in their research and did not show a decline with the addition of the microalga spirulina. Also, alcohol content was higher than in this research, above 4.5 % \(v/v\) for all samples. The lower alcohol content was probably a result of the high content of DRC(r) malt. To avoid astringent and bitter aromas and taste, native to dark ales, and to bring about the alga aromas, DRC(r) malt was used. Small amounts of hops (bitter and aromatic) were used too. This combination aimed to reduce the influence of raw materials such as malt and hops to beer brewed with algae. The high content of DRC(r) malt also contributed to the beer color, reducing the influence of alga addition. Heavier notes of dark ale matched the heavy notes of algae during boiling. The lower polyphenol content in beer with the addition of algae could be caused by the presence of carrageenan in alga biomass. Specifically, carrageenan is used as a fining agent during boiling. Fining agents are usually added to the wort approximately 10 min before the end of the boil. They tend to speed up the aggregation and sedimentation of the protein-protein and protein-polyphenol complexes during cooling [30]. Carrageenan