## 3 Results and Discussion
### Effect of Different Types on the Contents of B Vitamin and Phenolic Acids in Beers  
Vitamin B is an essential nutrient for basic metabolic activities in the human body and an important index for evaluating the nutritional value of beer. Different forms of vitamin B deficiency can lead to specific health problems [29; 45]. For example, vitamin B1 deficiency can lead to beriberi, whereas vitamin B2 and vitamin B6 deficiency are mainly manifested as skin inflammation and gastrointestinal discomfort. Vitamins B1, B2, B3 (nicotinic acid), B5, and B6 (pyridoxine) were detected in the different types of beers (Figure 3A). The content of B vitamins in draft beer is higher than that in ripe beer because heat treatment can lead to the loss of B vitamins during food processing [46]. In lager, the content of vitamin B3 was the highest, ranging from 170 to 251 \(\mu\)g/L, followed by B6, B5, B2, and B1. Excluding vitamin B2, the content of vitamin B in pure ripe beer was higher than that in classic ripe beer, with this same theory applying to draft beers. The content of vitamin B3 in pure draft beer B was the highest (250.10 \(\mu\)g/L). In ale, the content of vitamin B6 was the highest, followed by vitamins B3, B2, B5, and B1. In ale draft beer, the content of vitamin B6 was the highest (453.45 \(\mu\)g/L). Excluding B5, the content of B vitamins in ale was higher than that in lager. Vitamins B6 and B3 are the main vitamins found in beer [29], with the content of vitamin B1 being the lowest among all types of beer [47].  
Figure 2: The content of \(\beta\)-glucan in the examined beers. The concentrations of \(\beta\)-glucan in the different types of beer. CRB—classic ripe beer; CDB—classic draft beer; PRB—pure ripe beer; PDB—pure draft beer; ARB—ale ripe beer; ADB—ale draft beer. The different lowercase letters (a–d) are used to indicate significant differences in the different groups of data; i.e., the same letters indicate that there is no significant difference be-tween the two groups of data, and different letters indicate that there is a significant difference between them (\(p<0.05\)).  
Phenolic acid is one of the main phenolic compounds widely distributed in the diet and is characterized by strong antioxidant activity, anti-inflammation properties, and ease of intestinal absorption. This antioxidant activity is mainly influenced by the polyphenols present in beer [48]. The contents of ferulic acid, catechin, gallic acid, vanmillic acid, and protocatechuic acid in the different types of beer are detailed in Figure 3B. Depending on the detection results for phenolic acids, there was a significant difference in ferulic acid between draft beer and ripe beer. The content of phenolic acids in the draft beer was higher than than the values in ripe beer. The content of ferulic acid in the draft beer was higher than that in ripe beer, and phenolic acids are readily decomposed by heat, resulting in a decrease in their content [49]. Among the five phenolic acids, the ferulic acid content was the highest, followed by catechin, vanmillic acid, and gallic acid, and the protocatechuic acid content was very low. In lager, the contents of ferulic acid and vanmillic acid in classic draft beer were higher than those in pure draft beer, and the contents of other phenolic acids are lower than in pure draft beer, which is primarily the result of differences between malt and hops [50]. The ferulic acid content of ale draft beer (ADB) (3.73 mg/L) was the highest, which was 7.33% higher than that of ADB (3.46 mg/L), and the content of catechin ranked second. The above results are consistent with those of previous studies [51].