LEWISTON – The amount of local and natural food served at Bates College is growing thanks to a $2.5 million gift that’s earmarked for quality food.

Before receiving the first installment of the gift in 2006, the liberal arts school spent 22 percent of its annual food budget on local and natural foods. With the last installment of the gift now in hand, the percentage has risen to 28 percent.

Bates President Elaine Tuttle Hansen said the donation adds to students’ understanding of where their food comes from.

“We want to raise consciousness. We want to educate ourselves. We want to dispel our own ignorance and complacency by considering these issues,” she said.

An alumnus who wants to remain anonymous agreed in 2006 to give the school $2.5 million, as long as the money was put in an endowment with investment income going to supplement the food budget’s spending on local, natural and organic foods.

The final installment was made in June, and the college didn’t announce the donation until Wednesday.

These days, food served at the Bates dining hall includes grass-fed beef raised in Maine; spring water from a locally owned company; artisanal bread made from organic grain grown in Maine; and fruits and vegetables grown on farms a few miles from the Bates campus.

Bates is also trying to focus on food at more than just mealtime.

First-year students were given a summer reading assignment on food, and the school’s Web site includes a section on food with blog posts and a map showing which farms sell food to the school.