How many {physically interacts with} are to/by {food} ?
Which interacts physically with food?
What physically interacts with food?
SELECT ( COUNT ( ?o ) AS ?j ) { ?o property:physically_interacts_with resource:food }
SELECT (COUNT(?sub) AS ?subs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?sub .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P129> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q2095 .
} 

SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P129 wd:Q2095 }
15