An impedimetric dipstick sensor for the detection of hydrophobins in barley and malt extracts

Some batches of beer show excessive foaming or “gushing”. Little known to consumers, this quality issue leads to massive financial losses for breweries since gushing beer cannot be sold. The problem is caused by certain temperature-resistant proteins that originate from fungus infections of barley. These proteins typically occur in small quantities and are difficult to detect in barley, malt, and beer wort. This project aims at developing a compact, fast, and user-friendly sensor system enabling to detect and to quantify such contaminations selectively before the ingredients are used for beer brewing. The sensor will be based on impedance spectroscopy as detection principle combined with synthetic receptors as recognition elements for the proteins. A dipstick design with wire-shaped sensing electrodes combines the advantages of easy handling with a low cost per analysis.