Most Effificient Way to Store Ingredients in a Food Database
I think ingredients should go in a master table and another table to map ingredient to recipe. The following is the basic idea:

Create table recipe
(
    recipe_id int not null,
    recipe_name varchar2(50),
    constraint pk_recipe primary key (recipe_id)
);
Create table ingredient
(
    ingredient_id int not null,
    ingredient_name varchar2(50),
    constraint pk_ingredient primary key (ingredient_id)
);
Create table food_ingredient
(
    fk_recipe int not null,
    fk_ingredient int not null,
    measure number,
    unit_of_measurement varchar2(10)
);


Please note that the script above might have some errors due to syntax.

The advantage of this approach:


Finding food or recipe with similar ingredients
Finding food or recipe with a specific ingredient
Convert measurement, well you should incorporate some more tables to store unit of measurement and conversions. You've got the idea


Hopefully this would help.