Why might a brewer add dextrin malt to a brew?

Adding dextrin malt to a brew is primarily done to increase the body of the beer through the contribution of unfermentable sugars. Dextrin malts contain a higher proportion of complex carbohydrates that yeast cannot ferment, which helps to create a fuller mouthfeel and enhances the overall texture of the finished beer. This not only adds to the sensory experience but also balances the flavors, especially in beers with stronger bitterness or higher hop presence.

Dextrins also play a significant role in head retention, as they contribute to the stability and longevity of the foam. The use of dextrin malt is a common practice in brewing certain styles of beer that benefit from enhanced body and complexity, such as stouts, porters, and some pale ales.

Other answers, while related to brewing, do not align with the primary function of dextrin malt. For instance, accelerating fermentation speed and enhancing hop flavor are not characteristics attributed to dextrin malts, nor do they aid in clarification.