"The conditions were pretty tough and we also made too many mistakes but the Danish girls deserved to win.
"We feel like we are tracking really well for Tokyo. We had a pretty good buildup with not too many regattas this year.
"It's nice to finish it off with a third in Porto. It shows we are still in it and still very competitive. Hopefully next year we will do even better."
It is their first season back under the guidance of Nathan Handley, who coached them to their world title in 2013 and who also mentored Jo Aleh and Polly Powrie to Olympic gold and silver in the women's 470.
Maloney and Meech struggled in the first two races overnight, getting caught out on the wrong side of a big wind shift in the first race they couldn't recover from to finish 12th and followed it up with an eighth.
A 90-minute break onshore seemed to work wonders as they then finished second and first in the opening medal races which left them only six points off silver heading into the final race but they made too many errors again and rounded out their regatta with an eighth.
"It was a tough day for us," Meech said. "But we're pretty happy to come away with a bronze."
It was an excellent regatta for the new combination of Erica Dawson and Kate Stewart, who finished 13th in their first world championships together. They were as high as eighth going into gold fleet and narrowly missed out on the top-10 medal races.
"That was a fantastic effort from a new combination," Handley said. "It was really cool to have two Kiwi crews so high up in the standings."
A Kiwi crew was missing from the top step in the 49er fleet with Peter Burling and Kerikeri's Blair Tuke, who have won the last four world titles, absent from Porto.