Kopitiam, the biggest food chain operator in Singapore, has jacked up the price of a bottle of beer by $1.30 - three times what most coffee shops have opted for in the wake of the recent alcohol tax hike. Since raising duty on liquor by 25 per cent last week, the Government has warned shops against profiteering. The extra tax means a bottle of beer should cost, at most, 40 cents more. While most coffee shops here have kept any increase to between 40 cents and 60 cents, Kopitiam has pushed the price from $5.50 to $6.80 at its 80 outlets islandwide. Managing director Alden Tan denied the chain was taking advantage of the new tax, which was raised for the first time in a decade.