In the Sims2 how do you make your sims use their harvested produce?

No, you definitely don't need Pets. In the buy catalog, in the same place where you can find the coffee pots, microwaves, etc. is a juicer (also a hot cocoa machine). If you put the juicer out on a counter, there is a basket next to it. You can click on the basket and see an option for your sims to stock their produce (both fruits and veggies can be put into it -- so can the "boot" that they sometimes get when they are fishing).

Once you have enough of one type of fruit stocked into it, then you will see options to make juice.

Oh, but if you have them stock their fridge with the produce you cannot get it back out again. It is just automatically added to the food and that's why you will see "sparkly" food after they put produce into the fridge.

Here's the recipes and what each juice does when they drink it:

Apple Juice- 3 apples / 18 apples - Faster Homework

Beauty Cocktail- 2 oranges, 2 cucumbers / 12 oranges, 12 cucumbers - Acts like the love potion

Eggplant- 2 Eggplant / 12 Eggplant - adds a random skillpoint

Lemonade- 6 Lemons / 36 Lemons - cools them down

Orange Juice- 6 Oranges / 36 oranges - cures colds & flu

Orangeade- 4 Oranges, 2 Lemons / 24 Oranges, 12 Lemons - gives them random badge points, but they must have at least a bronze badge for this to work. Plus, it doesn't actually give them another badge unless they are close to getting it anyway.

Pepper Punch- 2 Peppers, 1 beans, 1 apples / 12 peppers, 6 beans, 6 apples - raises the level of their needs. In other words, if they are tired, they will be less tired. Great for pregnant sims.

Strawberry Juice- 3 Strawberries / 18 Strawberries - clears furious bits. Makes them less angry at a sim they are angry with.

Strawberry Lemonade- 2 Lemons, 2 strawberries / 12 Lemons, 12 Strawberries - raises their mood to platinum. Handy to have on hand if you are expecting an elderly sim to die soon.

Tomato Juice- 6 tomatoes / 36 tomatoes - warms sims up.

Vegetable Cocktail- 1 tomato, 1 cucumber, 1 Pepper, 1 Beans / 6 tomatoes, 6 cucumbers, 6 peppers, 6 beans - sims will learn skills faster

Pureed boot - 1 boot / 6 boots - sims will freak out, really quite funny to watch

You have to stock either your fridge or a juicer. If you stock the juicer you can make juices that will give the sims certain benefits. If you stock the fridge it keeps you from having to order food for a little longer.