By Anna Rice, News Staff

Tiny, colorful frozen yogurt shops already saturate cities like New York and Los Angeles, and now the trend has become full-blown in Boston.

First locally-owned shops like Berryline, which opened in Harvard Square in 2007 and now has locations in Fenway and Porter Square, and BoYO, which opened in May on Beacon Hill, began to gain popularity with local consumers. Then Los Angeles-based Red Mango opened at 334 Massachusetts Ave. near Northeastern’s campus last month, and celebrity favorite Pinkberry announced it would open a store in Harvard Square in spring 2010.

Fro-yo has quickly become more popular in Boston than some business owners originally thought it would. More than 2,500 people attended Red Mango’s grand opening event on Dec. 5, a number much higher than expected, especially since the event occurred on a cold, rainy day, franchise owner Tarang Gosalia said.

‘The turnout was way above what we had expected,’ he said. ‘We think that we’re going to have a really strong performance.’

Gosalia said he thinks his shop became popular quickly because it serves nutritious desserts that are low in calories. Red Mango’s frozen yogurt is made with natural ingredients, contains nutrients and live and active cultures, and is fat- and gluten-free. A half cup serving of frozen yogurt contains 90 calories, according to Red Mango’s website.

Gosalia said most of his customers have been local students and residents of the South End.

‘In Boston there is a very affluent community, and a lot of students,’ he said. ‘Northeastern in particular is a very health-conscious campus.’

Nutrition is one of the three leading culinary trend themes for 2009, according to National Restaurant Association research presented in their third annual chef survey, ‘What’s Hot in 2009.’

Lori Peljovich, owner of BoYO, said she thought nutrition was a factor in her shop’s popularity as well. BoYO’s frozen yogurt contains natural ingredients, nutrients and probiotics. A 1 ounce serving of BoYO frozen yogurt has 25 calories, according to their website.

‘It’s taken people in Boston a little while to get used to [frozen yogurt], but now that they’ve gotten used to it and know that it’s healthy, they just keep wanting more,’ she said.

In addition to promoting their products’ health benefits, stores like BoYO and Red Mango have focused their marketing efforts on students and young professionals by connecting with them via Twitter and Facebook and offering free in-store WiFi.

Red Mango also hosts events to draw customers into the store. Their first Acoustic Showcase on Nov. 24, where students from Berklee College of Music performed, drew more than 100 people, Gosalia said.

Many Northeastern students said they were excited that Red Mango opened near campus, and Gosalia said many have stopped by for a frozen yogurt. Walid Elhirach, a junior political science major, said he was thrilled when it finally opened.

‘It’s delicious,’ Elhirach said. ‘There weren’t enough fro-yo options in Boston before.’

Gosalia said he has already signed an agreement to open more franchises in the area, and he plans to open five over the next seven years.