Determining # of calories using coffee-cup calorimter

I created a coffee-cup calorimeter at home where I calculate the total amount of calories in a tortilla chip by burning the chip and measuring the temperature change of the water.


If the formula is Q = (m) (c) (ΔT)
where,
Q = s the energy in the form of heat captured by the water, expressed in calories, and
m = mass of the water expressed in grams, and
c = the specific heat capacity of water, and 
ΔT = change in temperature,


and my m=80grams, and temperature change was 20 degrees celsius, -does this mean the tortilla chip is 1.6 calories or do I have to multiply this value by 4.186 (which is the specific heat of water) to get a value of 6.69 calories? Thank you.


