{'refrigeration': [0, 0, 0, 1], 'food preservation': [0, 0, 0, 1], 'bacteria': [4, 1, 2, 3], 'ice': [0, 0, 1, 0], 'food': [18, 3, 8, 24], 'germs': [2, 1, 0, 1], 'biochemical reaction': [0, 0, 0, 1]}