That onion end, those celery leaves, and those carrot peels? They’re not garbage—they’re the foundation of broth that costs $4-6 per quart at the store.
The Story
Every time you cook, you generate vegetable scraps. Onion ends and skins. Carrot tops and peels. Celery leaves and bases. Garlic skins. Herb stems. Most people scrape them straight into the trash or compost without a second thought.
I used to do the same. Then I learned what culinary schools teach on day one: sort your scraps into separate bowls as you prep. One for what you are cooking, one for scraps that get frozen for stocks, one for the compost. In professional kitchens, vegetable peels, herb stems, and trimmings are saved, labeled, and turned into stocks for soups, stews, and sauces. The flavor comes from scraps that home cooks throw away.
Once I understood what I was discarding, I stopped. Now every vegetable scrap goes into a gallon freezer bag in the freezer. When the bag is full, I make broth—or I add the scraps to bone broth for extra depth. It takes maybe 15 minutes of hands-on work—and produces quarts of broth that rivals anything you’d buy.
Here’s what I love about this system: every batch is different. Each gallon bag has its own unique mix of scraps depending on what you cooked while filling it—whether that takes a week or a month. One batch might be heavy on mushrooms and leeks. Another might have more carrots and herbs. Each batch has its own flavor profile—and that keeps things interesting.
Here’s what convinced me: I was spending $4-6 per quart on boxed vegetable broth. Not because I couldn’t make it myself, but because I assumed it was complicated or time-consuming. It is not. It is literally simmering scraps in water. The scraps I was already generating and throwing away.
The math is simple. A quart of good broth at the grocery store runs $4-6. Our household uses maybe 2-3 quarts per month for soups, risotto, cooking grains, and deglazing pans. That is $8-18 per month, or roughly $100-200 per year—on something I can make for free from food I am already buying.
Key Details
Time Investment: 15 minutes active work | Cost: $0 (uses scraps you already have) | Yield: 2-3 quarts per batch
Sustainability Note: Every batch of scrap broth represents food that would have gone to waste, packaging you did not buy, and money that stayed in your pocket. Zero downside, maximum win.
What to Save
Not all scraps are created equal. Some add great flavor. Some add off-flavors. Here’s what goes in my freezer bag—and what does not.
The Yes List
| Scrap | Why It Works |
|---|---|
| Onion ends, skins, and layers | Deep, savory flavor base—leave the papery skins on for golden color |
| Carrot tops, peels, and ends | Sweetness and earthiness |
| Celery leaves, bases, and trimmings | Classic broth flavor, aromatic |
| Garlic skins and ends | Subtle garlic undertone without being overpowering |
| Leek tops (green parts) | Mild onion flavor, often discarded but excellent for broth |
| Herb stems (parsley, thyme, cilantro) | Concentrated herb flavor—stems have more than you think |
| Mushroom stems and trimmings | Deep umami, rich color |
| Scallion roots and tops | Mild allium flavor |
| Fennel fronds and cores | Subtle anise note, great for certain dishes |
| Corn cobs (kernels removed) | Sweet, summery flavor—save after eating corn on the cob |
| Tomato cores and skins | Acidity and color (use sparingly) |
| Bell pepper cores and seeds | Mild sweetness (remove white pith if bitter) |
The No List
| Scrap | Why to Skip It |
|---|---|
| Brassicas (broccoli, cabbage, Brussels sprouts, kale stems) | Turn bitter and sulfurous when simmered |
| Beets | Overwhelm with color and earthy flavor—save for borscht |
| Artichokes | Bitter |
| Asparagus | Can become bitter |
| Hot peppers | Unless you want spicy broth |
| Potatoes | Make broth starchy and cloudy |
| Zucchini/summer squash | Watery, don’t add much flavor |
| Anything moldy or rotten | Obviously |
The Maybe List
| Scrap | Notes |
|---|---|
| Parsnip peels | Adds sweetness—some people love it, some find it too strong |
| Turnip peels | Mild flavor, use sparingly |
| Winter squash seeds and strings | Subtle flavor, can use in small amounts |
| Ginger peels | Great for Asian-style broths |
How I Do It
Here’s my system. It requires almost no effort—just a freezer bag and a pot.
Step 1: Collect Scraps
Keep a gallon-size freezer bag in your freezer. As you cook, toss in the scraps from the Yes List. Onion ends go in. Carrot peels go in. Celery leaves go in. Takes two seconds.
My actual system: I often have several partial bags going at once. As I fill them, I try to keep any single scrap from dominating—if a bag is already half onion, I will start adding onion ends to a different bag. This keeps each batch balanced.
Important for canners: Root vegetable skins (carrot peels, parsnip peels, etc.) should not be pressure canned—the USDA guidelines require peeled vegetables for canning. I keep root peels in a separate bag so I know that batch needs to be used immediately or frozen, not canned. If you are not canning your broth, this does not matter.
The bag lives in the freezer, so nothing rots or smells. Frozen scraps actually break down better when simmered, releasing more flavor. And the freezer bags can be reused—rinse them out after emptying and they are ready for the next batch of scraps.
When the bag is full (or close to it), it is time to make broth—or time to add the scraps to a batch of bone broth.
Step 2: Make the Broth
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Dump the frozen scraps into a slow cooker. No need to thaw—frozen is fine. I prefer a slow cooker so the broth can simmer all day while I am at work.
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Cover with water. Use about 10-12 cups of water per gallon of scraps. The scraps should be submerged with an inch or two of water on top.
-
Add aromatics (optional).
- 1-2 bay leaves
- 5-10 whole black peppercorns
- A few sprigs of fresh thyme or parsley (if you have them)
- Salt to taste (I add about 1 teaspoon, but you can leave it unsalted and season when you use the broth)
-
Cook low and slow. Set to LOW and let it simmer for 6-8 hours (or all day). On the stovetop, bring to a boil, reduce to a simmer, and cook for 45 minutes to 2 hours. Longer cooking extracts more flavor.
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Strain. Pour through a jelly strainer or cheesecloth or fine-mesh strainer. Press on the solids to extract all the liquid. Discard the solids.
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Cool and store. Let the broth cool to room temperature, then refrigerate or freeze.
That is it. Fifteen minutes of actual work, most of it passive simmering.
Step 3: Store the Broth
Refrigerator: Up to 5 days in a sealed container.
Freezer: Up to 6 months. I freeze in:
- Quart containers for soups and big batches
- Ice cube trays for small amounts (deglazing, cooking grains)—pop the cubes into a freezer bag once frozen
Note on canning: The USDA and NCHFP have not published tested procedures for pressure canning plain vegetable broth. This means vegetable-only broth should be refrigerated or frozen, not canned. However, if you add your veggie scraps to bone broth, the combined broth can be pressure canned following NCHFP meat stock instructions—just remember that root vegetable peels cannot be included in broth you plan to can.
Why This Matters
The money math: 2-3 quarts of broth per batch × $4-6 per quart = $8-18 of broth from scraps you were throwing away. Do this once a month, and you save $100-200 per year.
The waste math: Every batch of scrap broth represents a gallon of food scraps that did not go to the landfill—plus the plastic or cardboard packaging from the store-bought broth you did not buy.
The flavor math: Homemade broth tastes better. It just does. You control the salt, the aromatics, and the quality of the ingredients. Store-bought broth often contains additives, preservatives, and excessive sodium. Your scrap broth contains vegetables and water.
The time math: Fifteen minutes of hands-on work for 2-3 quarts of broth. That is less time than driving to the store to buy it.
Pro Tips from Our Kitchen
Build your scrap collection at your own pace. Filling a bag might take a week if you cook daily, or a month if you cook less often—either way works perfectly. The scraps stay frozen indefinitely, so there’s no rush. Prep vegetables with broth in mind—save those onion ends instead of tossing them automatically.
Balance your scraps. A bag that is 90% onion skins will make onion broth. As I fill bags, I try to keep any one scrap from dominating—if a bag is already heavy on onions, I start adding onion ends to a different bag. Multiple partial bags in the freezer is normal.
Roast for deeper flavor. For a richer, more complex broth, spread the frozen scraps on a sheet pan and roast at 400°F for 20-30 minutes before simmering. The caramelization adds depth. This is optional but noticeable.
Add scraps to bone broth. I rarely make standalone veggie broth—I usually add my veggie scraps directly to bone broth for extra depth and complexity. The vegetables complement the richness of the bones. Same freezer bag system, different destination.
Label your containers. “Veggie broth - Jan 2026” prevents freezer mystery containers.
Keep a second bag for bones. Same system works for chicken carcasses, turkey carcasses, and steak bones. When the bone bag is full, make bone broth. Two freezer bags, two kinds of free broth.
What NOT to Do
Do not use the No List vegetables. Brassicas, beets, and potatoes will ruin your broth. Learn from my mistakes—one batch with too much broccoli stems taught me this lesson.
Do not boil vigorously. A gentle simmer extracts flavor without making the broth cloudy or bitter. Bubbles should barely break the surface.
Do not skip straining. Nobody wants gritty broth. Strain through a jelly strainer or cheesecloth or fine-mesh strainer. Jelly strainers or cheesecloth work great and are reusable.
Do not add salt if you’re unsure. You can always add salt when you use the broth. You cannot remove it. I make mine lightly salted and adjust when cooking.
Do not let scraps sit at room temperature. Into the freezer immediately. Room-temperature scraps rot. Frozen scraps keep indefinitely.
Uses for Your Broth
Once you have quarts of homemade broth, you will find uses everywhere:
- Soups and stews (obviously)
- Cooking rice: Replace water with broth for more flavorful rice
- Deglazing pans: A splash of broth to lift the fond beats water every time
- Braising vegetables: Cook greens, root vegetables, or beans in broth instead of water
- Mashed potatoes: Use broth instead of some of the milk/cream for extra flavor
- Sauces and gravies: Broth adds body and depth
The Real Benefit
This is not about being a perfect zero-waste household. This is about recognizing that something you are already throwing away has actual value—flavor value, money value, and environmental value.
I have not bought vegetable broth in years. My soups taste better. My rice has more depth. And every time I make a batch, I am turning food scraps into something useful instead of sending them to a landfill.
It takes a freezer bag and 15 minutes of work. Save your scraps from tonight’s dinner, start a bag, and see how fast it fills up. You will be surprised how much free broth you have been throwing away.
Quick Reference
My System:
- Keep a gallon freezer bag in the freezer
- Add vegetable scraps as you cook (onions, carrots, celery, herbs, garlic, mushrooms)
- Skip brassicas, beets, and potatoes
- When bag is full, dump into pot, cover with water
- Add bay leaves and peppercorns, simmer 45-60 minutes
- Strain, cool, store in fridge (5 days) or freezer (6 months)
What You Will Need:
- Gallon freezer bags (reusable)
- Slow cooker or large pot
- Jelly strainer or cheesecloth or fine-mesh strainer
- Storage containers (quart jars, plastic containers, or ice cube trays)
Best Scraps:
- Onion ends, skins, and layers
- Carrot tops, peels, and ends
- Celery leaves and bases
- Garlic skins
- Herb stems
- Mushroom trimmings
- Leek tops
Expected Results:
- 2-3 quarts of broth per gallon of scraps
- $8-18 worth of broth per batch
- Better-tasting soups and rice
- Less food waste
- No packaging waste
Links & References
- More Wednesday Wisdom: Eggshells Aren’t Trash—another kitchen scrap that is worth saving
- Preservation Tips: Why We Preserve—the philosophy behind saving and storing
- Coming Soon: Saving Bones for Broth (the freezer bag system for bones), Homemade Bone Broth (same concept, different scraps)
Sources
- 10 Tips I Learned in Culinary School to Reduce Food Waste - FoodPrint — culinary school training on sorting scraps for stock
Your vegetable scraps are not garbage. They are ingredients. The best chefs know this. Now you do too.