Analysis of improved nutritional composition of bee pollen (Brassica campestris L.) after different fermentation treatments

Summary Microbial fermentation as an excellent food processing technology has been used for improving the flavour and nutritional feature of food material. In this study, we compared the differences in the nutrient profile of bee pollen (rape bee pollen , Brassica campestris L., BP) fermented with different species of microbes, such as lactic acid bacteria (LAB), yeast, and the two mixed. Based on the nutritional components and multivariate statistical analysis, yeast fermentation has more advantage for BP than fermentation with LAB or mixed microbes. The yeast‐fermented BP has an 83.5% reduction in fructose and 87.4% reduction in glucose, while phenolic compounds, oligopeptides and fatty acids were increased by 9.3%, 68.8% and 18.2%, respectively, compared with the BP without fermentation. The contents of riboflavin, nicotinic acid, nicotinamide and free amino acids in the pollen fermented by yeast were 2.4, 39.6, 4.6 and 4.8 times higher than those in raw BP, respectively. Additionally, in the fermentation process, wall‐breaking pollen showed more advantages in the transformation of nutrients, free amino acid increased by 11% at least, more low molecular weight peptides produced and nicotinic acid and nicotinamide increased by 7% at least, compared with fermented BP. Taken together, these results showed that BP with yeast fermentation has great potential in obtaining high available nutritional products.