[{"name":"store1","products":[{"name":"product 1","reviews":[{"user":"john doe","stars":5,},{"user":"jane doe","stars":1,}]},{"name":"product 2","reviews":[{"user":"jane doe","stars":3,}]}]}]

db.collection.update({"products.reviews.stars":1},{"$pull":{"products":{"reviews.stars":1}}})