Food inflation surged back into double-digit territory, at 12.13 per cent, for the week ended December 11, from 9.46 per cent in the previous week, as the prices of vegetables, particularly onions, rose for the third consecutive week. Food inflation has now entered double digits for the first time since November 13, when it had stood at 10.15 per cent. On an annual basis, onions became costlier by 33.48 per cent, whereas on a week-on-week basis, the increase was 4.56 per cent, according to government data. Fruits became 20.15 per cent costlier, and milk 17.83 per cent more expensive, year-on-year, and vegetables became 15.54 per cent dearer.