7.a. 1) As we have seen, juice may be squeezed onto food other than a liquid, to improve its flavor, but this is subject to two provisos:
a) the squeezing must be done by hand and not with an instrument designed for the purpose and
b) all or, at least, most of the juice extracted must in fact be utilized to improve the taste of the food. 2) This is permitted even if the juice is not absorbed in the food.
7.b. One is consequently allowed
1) to squeeze a lemon onto a salad or fish and also
2) to squeeze an orange into mashed banana for a baby. (See further Chapter 6, paragraph 8 and Chapter 8, paragraph 14.)
7.c. It is, however, forbidden to squeeze a lemon or an orange into an empty vessel, even if one intends to pour the juice onto food in order to improve its taste.