What is the difference between stock and broth? The line drawn for me in culinary school was that stock was made with bones and broth was not. Enter the rise of bone broth – a liquid derived from long-simmered bones and water that can cure many ills, be found in many forms and be purchased for many dollars. The bone broth-erhood has muddied my previously neat partition.

But as the eminent food scientist Harold McGee has done on many other occasions along my cooking career, he’s set the record straight by looking at the debate from a different angle. In a succinct sidebar in his seminal book, “On Food and Cooking: The Science and Lore of the Kitchen” (it’s not in my 1984 copy but thanks to a Google Books preview page and then my local bookseller, I’ve read it both electronically and on the page), McGee argues that the most important difference between stock and broth is intended use.

Stock serves as a basic building block for sauces, soups and stews, blending in with the other ingredients to become the finished dish. Alternatively, broth is a liquid that – while it can function like stock in a pinch – is made with the intent that it will be sipped and savored on its own or with just a bit of substance added. Think chicken broth and rice; mushroom tortellini in Parmesan broth; beef bone broth; or vegetable broth with potatoes, garlic and almonds.

This separation by intended use serves me just fine. In my family’s attempt to eat less meat as a sustainable eating proposition, fewer bones now come through my kitchen. Instead, many, many more vegetable scraps get stored in the freezer until I’ve amassed enough to make a rich, savory vegetable broth that can hold its own as a frequent replacement for my favored chicken broth.

After about two months of testing, I’ve finally got my formula down: 2 tablespoons olive oil, 2 pounds of balanced raw vegetable and herb scraps; 12 cups of cold water; 12 whole black peppercorns, 6 allspice berries and 1 tablespoon tomato paste.

Two pounds of raw vegetable and herb scraps are weighed – they’ll form the backbone of homemade vegetable broth. Brianna Soukup/Staff Photographer

What do I mean by balanced scraps? To make my broth, I include equal amounts of pungent flavors (from onion and garlic trimmings; shallot skins; leek tops or scallion bottoms); sweet flavors (from fennel cores, stalks and fronds; carrot, parsnip and sweet potato peels; or red and yellow pepper caps, veins and seeds); and savory flavors (from mushroom stems; parsley and thyme stalks; celery tops and cores).  If I am short on savory tones, I add a strip of seaweed, typically kelp or dulse. (If any eaters of your broth are allergic to shellfish, skip the seaweed.)

I use one-third of each tone in my medley. I don’t plan my vegetable cookery for the week around that ration; rather I store all the scraps, categorized according to these divisions, in reusable containers in the freezer. When I have enough to fulfill the requisite ratio and a spare hour or two to hang around the house while they simmer in the pot, I make broth.

This formula will yield 10 cups of lightly flavored broth if you let everything simmer together for about 45 minutes, after which the process can extract no more flavor out of your spent scraps, which you strain out and then compost. But if you let the broth continue to simmer to reduce further to concentrate its flavor, after an hour and a half you’ll get 8 cups of excellent broth. Wait 45 minutes more and you’ll be rewarded with 6 six cups of rosy (thanks to the tomato paste) liquid gold.

Christine Burns Rudalevige is a food writer, recipe developer and tester and cooking teacher in Brunswick, and the author of “Green Plate Special,” a cookbook from Islandport based on these columns. She can be contacted at:

cburns1227@gmail.com

Rich Vegetable Broth with Potatoes, Garlic and Almonds

This is a vegetarian riff on the Andalusian soup that cookbook author Anya von Bremzen included in “The New Spanish Table.” The combination works really well, provided you’ve made a good vegetable broth.

Serves 2 heartily, 4 lightly

1 ½ pounds Yukon Gold potatoes

¼ cup extra-virgin olive oil

½ cup blanched, slivered blanched almonds

6 large garlic cloves, peeled and cut in half

1 teaspoon kosher salt

1/2 teaspoon coarsely ground black pepper

1/2 teaspoon dulse flakes

1/2 teaspoon smoked paprika

4 cups rich vegetable broth, or more if needed

2 teaspoons sherry vinegar, or more to taste

2 tablespoons minced flat-leaf parsley

Dense country bread, for serving

Cut the potatoes, unpeeled, into irregular 1½-inch chunks and set aside.

Heat the olive oil in a heavy 3-quart saucepan over medium heat. Add the almonds and garlic, and cook, stirring, until golden, 4 to 5 minutes, adjusting the heat so the ingredients don’t burn. Remove the pan from the heat. Use a slotted spoon to transfer the almonds and garlic to a bowl to cool slightly. Finely chop the almonds and garlic together, and set aside.

Return the pan to medium heat. Add the potatoes, salt, pepper, dulse flakes and smoked paprika, and cook, stirring, for another minute. Add the vegetable broth and bring to a boil, skimming off any foam that rises to the surface. Add all but about 2 tablespoons of the almond mixture to the soup. Reduce the heat to medium low and simmer the soup, partially covered, until about half the potatoes have disintegrated, about 35 minutes. Add a little more stock if the soup seems too thick for your taste.

When you are ready to serve it, check the texture of the soup. If you’d like it creamier, break up some of the potatoes with a sturdy spoon. Add the vinegar to the reserved ground almond mixture. Stir in the parsley. Ladle the soup into bowls and garnish it with the almond-vinegar mixture. Serve the soup with bread.