( ( ( Calories - ) ( ( Fuel ( or ( energy value ) ) ) ( of ( ( ( food as ) ( expressed ( by ( ( the amount ) ( of heat ) ) ) ) ) ( necessary ( to ( raise ( ( one gram ) ( of ( water ( one ( degree Celsius ) ) ) ) ) ) ) ) ) ) ) ) . )
(ROOT (NP (NP (NNS Calories)) (: -) (NP (NP (NN Fuel) (CC or) (NN energy) (NN value)) (PP (IN of) (NP (NP (NN food) (RB as)) (VP (VBN expressed) (PP (IN by) (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NN heat)))))) (ADJP (JJ necessary) (S (VP (TO to) (VP (VB raise) (NP (NP (CD one) (NN gram)) (PP (IN of) (NP (NN water) (CD one) (NN degree) (NNS Celsius))))))))))) (. .)))
Calories- Fuel or energy value of food as expressed by the amount of heat necessary to raise one gram of water one degree Celsius.
(ROOT (S (NP (NP (DT The) (NN energy) (NN content)) (PP (IN of) (NP (NNS foods)))) (VP (VBZ is) (ADVP (RB often)) (VP (VBN expressed) (PP (IN in) (NP (NNS calories))))) (. .)))
The energy content of foods is often expressed in calories.