( ( ( The ( chemical energy ) ) ( of foods ) ) ( ( ( is ( most often ) ) ( expressed ( in ( units ( of ( ( ( calories or ) kilocalories ) ( -LRB- ( kcal -RRB- ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ chemical) (NN energy)) (PP (IN of) (NP (NNS foods)))) (VP (VBZ is) (ADVP (RBS most) (RB often)) (VP (VBN expressed) (PP (IN in) (NP (NP (NNS units)) (PP (IN of) (NP (NP (NNS calories) (CC or) (NNS kilocalories)) (PRN (-LRB- -LRB-) (ADJP (JJ kcal)) (-RRB- -RRB-)))))))) (. .)))
The chemical energy of foods is most often expressed in units of calories or kilocalories (kcal).
(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.