Beer lovers may soon have a gut-friendly drink to raise a toast to, thanks to the creation of a novel probiotic sour beer by a team of researchers from the National University of Singapore (NUS). This new specialty beer incorporates the probiotic strain Lactobacillus paracasei L26, which was first isolated from human intestines and has the ability to neutralise toxins and viruses, as well as regulate the immune system.

The idea of producing a probiotic beer was first mooted by Miss Chan Mei Zhi Alcine, a fourth-year student from the Food Science and Technology Programme under the NUS Faculty of Science, who consumes dairy-based probiotic beverages daily.

Infusing beer with health benefits

Studies have shown that consuming food and beverages with live counts of probiotics are more effective in delivering health effects than eating those with inactive probiotics. Currently, the recommendation by the International Scientific Association for Probiotics and Prebiotics is to have a minimum of 1 billion probiotics per serving in order to attain the maximum health benefits.

Under the supervision of Associate Professor Liu Shao Quan from the NUS Food Science and Technology Programme, Miss Chan took about nine months to come up with an ideal recipe that achieves the optimal count of live probiotics in the beer.

By propagating the probiotic and yeast in pure cultures, and modifying conventional brewing and fermentation processes, Miss Chan managed to increase and maintain the live counts of the strain of probiotic. "For this beer, we used a lactic acid bacterium as a probiotic micro-organism. It will utilise sugars present in the wort to produce sour-tasting lactic acid, resulting in a beer with sharp and tart flavours. The final product, which takes around a month to brew, has an alcohol content of about 3.5 per cent," explained Miss Chan. The NUS research team has filed a patent to protect the recipe for brewing the probiotic sour beer.