The consensus with dextrin malt is that it helps with head retention. However, a 2013 research states otherwise. According to the research, dextrin malt falls under the category of foam-negative species. The implication of this research is that the foam retention property of dextrin malt is just a myth.
However, while the research offers interesting information about the retention property of dextrin malt, little has changed regarding its use for retention in beers. This is because many brewmasters don’t consider the research definitive, and understandably so, considering the success with foam retention widely attributed to dextrin malt for several years now.