ingredient=
food
,
2
piece
;
In[]:=
EntityInstancePart[ingredient,1],
1
item

default item size mass
*Part[ingredient,2,1]*EntityInstancePart[ingredient,1],
1
item

relative calorie content

Out[]=
30.66
Cal
In[]:=
EntityInstancePart[ingredient,1],
1
item
["TotalCaloriesContentPerItem"]*Part[ingredient,2,1]
Out[]=
37.
Cal