"One or a few legitimate" cryptocurrencies are coming, but bitcoin is not one of them, according to Starbucks' executive chairman and former CEO, Howard Schultz.

"I don't believe that bitcoin is going to be a currency today or in the future," Schultz said, during a post-earnings conference call Thursday after the closing bell on Wall Street. (Shares of Starbucks were under pressure on Friday after another quarter of disappointing sales growth as holiday offerings failed to draw in customers.)

Instead, Schultz told investors he sees potential in blockchain, the online ledger technology underlying digital currencies. "I'm talking about ... the possibility of what could happen — not in the near term, but in a few years from now — with a consumer application in which there's trust and legitimacy with regard to a digital currency."

"I'm not bringing this up because Starbucks is announcing that we are forming a digital currency or we're investing in this," Schultz said, according to audio of the call on the Starbucks website. "I'm bringing this up ... as we think about the future of our company and the future of consumer behavior."

Last month, Schultz told CNBC he could see a future in which the U.S.-based coffee chain would be cashless one day. He joined Starbucks in 1982 as director of operations and marketing. He served twice as CEO, a role he turned over to Kevin Johnson last April.