Of course we could compost our kitchen scraps but some can be used in other ways as well:
Make stock (or freeze for later) from scraps of onions (but not too many of the papery, bitter tasting skins), leeks, garlic, carrots, parsnip, celery, mushrooms - even hard cheese rinds - to make stock later. For a quick veggie stock, caramelize veggies scrapes in a little bit of oil and add any other scrapes from your soup recipe, herbs (such as bay leaf, parsley, thyme, and sage), enough water to generously cover and a bit of salt if you like. Bring to a boil and simmer for a half hour for a rich vegetable stock. Strain out the veggie bits and compost or feed to animals (my dogs always loved these super soft veggies)
dog snacks (some dogs like raw broccoli and other veggies or fruits as well)
Feed chickens and ducks your greens, tomato bits, strawberry tops, melon rinds & seeds...
Broccoli stems can be peeled and chopped small or grated, raw in slaw or salads, or cooked where ever you use the florets. I actually prefer crisp broccoli stalks to the florets.
Tough vegetable parts (like chard stems and leek greens) can be sautéed until soft for eating.
Use stale bread and heels for bread crumbs and croutons (or freeze for later).
Increase nutrient value and decrease waste if you leave peels on and scrub vegetables clean when cooking with carrots, potatoes, parsnips and turnips.
If unpasteurized (raw) juice starts to "go bad," keep it loosely covered and it will eventually turn into wine or vinegar (I've currently got apple juice and blueberry juice converting in my cupboard).
If unpasteurized (raw) milk starts to sour (but still smells pleasant), use it in baking (pancakes or breads), desserts (cakes, cheesecake or custard), cooking (like mashed potatoes, soups, casseroles, or scrambled eggs), turn it into cheese...
After cooking, reuse nutrient-rich (unsalted) pasta and potato water in bread making, baking, soups or other recipes that call for water. Or use it in the garden!