The applicability of Calcofluor White (CWS) and Fluorescent Brightener (CFB) dyes for confocal laser microscopic analysis (CLSM) of various β-glucans in selected dairy products and water

The aim of this study was to determine the applicability of commonly used dyes (CWS and CFB) to stain different types of β-glucans in water and selected, most popular, dairy products for CLSM imaging analysis. Structurally different pure β-glucan preparations: curdlan-CU, oat β-glucan-OG and scleroglucan-SC were tested. Our study showed for the first time that CWS is a dye with a specific affinity for all analyzed β-glucans, while CFB is suitable for curdlan labeling only. Despite the technological processes, β-glucans structures in dairy products are similar to those in aqueous suspension forms; each of the β-glucans forms a different and characteristic structure, ranging from spindle-shaped and branched till granular. The presented results for the first time systematize the knowledge on CWS and CFB applicability in β-glucan CLSM staining and allow future researchers to correctly analyze simultaneously stained β-glucan, fat, and protein in a complex matrix as dairy products.