According to Goldman Sachs, the declining popularity of hard seltzer brand Truly is going to dampen Boston Beer’s momentum. Analyst Bonnie Herzog downgraded Sam Adams Brewer’s shares from neutral to sell, saying in a Tuesday note that low consumer interest in hard seltzer, and a lackluster product pipeline, would weigh down its sales. “We continue to be more cautious on SAM and are downgrading our rating from neutral to sell following recent feedback from our beer distributor contacts, indicating that Trulli’s momentum has further eroded,” Herzog wrote. Goldman Sachs cut its 12-month price target to $318, a 16% cut. The new price target is about 5% lower than the shares closed on Monday. Herzog expects shipments of Trulli to drop by about 22% this year as its popularity stalls. About 60% of distributors said that cut retail shelf space for Truly this year, and Truly demand is falling even faster than the broader hard seltzer category. Still, Boston Beer could get a boost from soaring Twisted Tea sales this summer. He added that Twisted Tea shipments are expected to grow by 20 per cent. Other innovations include the roll out of Hard Mountain Dew and Truly a wider range of products. However, Herzog said he doubts whether this is enough, citing a lack of enthusiasm for his opinion among distributors. “Against this background, an important debate emerges for SAM: Are SAM’s efforts with a strong outlook for Twisted T and innovations enough to offset a significantly more bearish outlook for Truly? We don’t think so. ,” She wrote. Boston Bear shares fell more than 3% in Tuesday’s premarket trading. —CNBC’s Michael Bloom contributed to this report.