Along with Peralta, the Brewers recalled right-hander Tyler Thornburg and outfielder Logan Schafer from Triple-A Nashville, and right-hander Josh Stinson from Double-A Huntsville.
All four players were already on Milwaukee's 40-man roster.
Peralta was 7-11 with a 4.66 ERA in 28 starts with Nashville, and he made his Major League debut in a relief appearance with the Brewers on April 22 vs. the Rockies. He will make his first Major League start Wednesday opposite Miami's Nathan Eovaldi, the right-hander who, while still with the Dodgers, opposed the Brewers' Mike Fiers in Fiers' debut start on May 29.
"He's had real good velocity the whole year," manager Ron Roenicke said of Peralta. "[Throwing] strikes was the issue early on, walking too many people. We hope the nerves don't take over. Hopefully he could get out there and throw strikes."
Thornburg is in his third stint with Milwaukee (also June 19-20, when he made his Major League debut, and July 13-29), and the Brewers plan to get him a couple of starts this month. Schafer batted .278 with 11 home runs, 40 RBIs and 16 stolen bases in 124 games with Nashville. Roenicke said Schafer, who made his Major League debut last season, will likely serve as a pinch-runner and late-inning defensive replacement.
"I'm just ready for whatever they give me and whatever opportunity I'm able to get," Schafer said. "I'm just trying to have a good time and help win ballgames if I get the opportunity."
Stinson, 24, was claimed off waivers from the Mets on April 4, and went 11-9 with a 3.16 ERA in 29 games (24 starts) with Huntsville. His 11 wins tied for the most among Brewers Minor Leaguers and were tied for second in the Southern League, and his 3.16 ERA ranked third in the league.
Stinson's impressive second-half numbers, as well as the fact that he was already on the 40-man roster and had Major League experience (14 appearances with the Mets last season) were all factors into the decision to bring him up for the final month of the season.
Stinson will join Livan Hernandez in a middle-relief role with the Brewers, but he was likely unavailable Tuesday because he started for Huntsville three days ago.
"I know he's a starter this year, but he's been in the bullpen before and has some Major League experience with the Mets," Roenicke said.
Adam McCalvy is a reporter for MLB.com. Read his blog, Brew Beat, and follow him on Twitter at @AdamMcCalvy. Associate reporter Tom Green contributed to this report. This story was not subject to the approval of Major League Baseball or its clubs.