To make soup in bulk, write the recipe by weight as percentages, cook it in one big kettle, and then do the part that matters most at scale: cool it fast. A stockpot cools on the counter in an hour; 40 gallons stays warm in the middle for most of a day unless it's broken up and chilled, and soup that sits warm is how a kitchen makes people sick. Done this way, a soup maker that cooked 20 pounds on the stove makes about 150 quarts in a day, and the cost of a quart falls from $10.95 to $3.60. Below is the recipe at two sizes, the steps, the cooling, what a quart costs at each size, and a free scaling calculator.
The short version
- Weigh every ingredient once and turn the recipe into percentages.
- Cook the run in one kettle sized to it.
- Cool fast: from 135°F to 70°F within 2 hours, then to 41°F within 4 more.
- Break the batch up with ice wands and shallow pans, and log the temperatures.
- Fill quarts cold, dated and labeled.
- Weigh what comes out and use your real cook loss to cost a quart.
- TaroStack keeps the recipe by weight, takes each batch's ingredients off stock and checks its yield. More below.
The recipe, by percentage
Mill Race Soup Co., the made-up soup maker in Burlington, Vermont, I use in these examples, cooked 20 pounds at a time until a co-op ordered 150 quarts a week. Its white bean and kale soup, weighed:
| Ingredient | % of the mix | Kitchen batch, 20 lb | One batch, 320 lb | The run, 320 lb | Cost a lb, bought in bulk |
|---|---|---|---|---|---|
| Vegetable stock | 45% | 9.00 lb | 144.0 lb | 144.0 lb | $0.60 |
| White beans, cooked | 18% | 3.60 lb | 57.6 lb | 57.6 lb | $1.20 |
| Crushed tomatoes | 10% | 2.00 lb | 32.0 lb | 32.0 lb | $1.20 |
| Kale | 6% | 1.20 lb | 19.2 lb | 19.2 lb | $2.50 |
| Onion | 6% | 1.20 lb | 19.2 lb | 19.2 lb | $0.50 |
| Carrots | 5% | 1.00 lb | 16.0 lb | 16.0 lb | $0.55 |
| Celery | 4% | 0.80 lb | 12.8 lb | 12.8 lb | $0.80 |
| Olive oil | 2% | 0.40 lb | 6.40 lb | 6.40 lb | $6.00 |
| Small pasta | 2% | 0.40 lb | 6.40 lb | 6.40 lb | $1.00 |
| Garlic | 1% | 0.20 lb | 3.20 lb | 3.20 lb | $2.80 |
| Salt | 0.8% | 0.16 lb | 2.56 lb | 2.56 lb | $0.40 |
| Dried herbs | 0.2% | 0.04 lb | 0.64 lb | 0.64 lb | $12.00 |
| The whole mix | 100% | 20 lb | 320 lb | 320 lb |
The 320 pounds cost $333.02 in ingredients. The stock is nearly half the weight, so making it in the kitchen from vegetable trimmings saves more than any other ingredient. How percentages work for other recipes is in scaling recipes for production.
The steps, at 320 pounds
- Sweat the vegetables. Onion, carrots, celery and garlic in the oil, in the kettle.
- Build the soup. Stock, beans, tomatoes and herbs, brought to a simmer; the kale and pasta go in at the end so they don't turn to mush.
- Start cooling at once. Frozen ice wands in the kettle, stirred, then the soup moved into shallow pans no more than 2 inches deep.
- Chill and log. Pans into the blast chiller, two loads for the run; the temperature written at 2 hours (70°F or below) and at 6 hours (41°F or below). The log is in cooling log template.
- Fill cold. Quarts filled from the chilled soup, lidded with tamper-evident lids.
- Weigh what comes out. Over three runs, the kettle loses about 5% to steam.
- Label and date. Every quart carries the run's lot, the date and "Keep refrigerated".
The run takes one person about 8 hours, from chopping to the last quart in the cooler.
What a quart costs at each size
| Per quart | Kitchen batch, 20 lb | Bulk run, 320 lb |
|---|---|---|
| Ingredients | $4.17 (grocery prices) | $2.19 (bought in bulk) |
| Packaging | $0.45 | $0.36 |
| Labor at $20 an hour | $6.33 (19 min a quart) | $1.05 (3.2 min a quart) |
| Cost of a quart | $10.95 | $3.60 |
The ingredients fall by half, mostly because the stock is made rather than bought by the box, and the labor falls by five-sixths: a 40-gallon kettle takes about the same attention as a stockpot. The co-op pays $8.50 a quart, which the kitchen batch couldn't cover; the bulk run can. The year is in soup business plan.
Why cooling is the step to watch
The FDA Food Code's cooling rule, which most states adopt, is 135°F to 70°F within 2 hours and to 41°F within 6 hours in all. A kettle of soup left to cool on its own misses both, and the middle sits in the range where bacteria grow fastest. Ice wands, shallow pans and a blast chiller are how a bulk kitchen meets it, and the log is the proof. The containers are in how to package soup for sale.
Get the calculator
Download the soup scaling calculator. Two sheets: scale the recipe, where you type each ingredient's percentage and cost a pound and the raw mix you want, and each ingredient's weight for the run fills in, with the kettle cooks, chiller loads, what comes out after the cook loss, the quarts it fills and the cost of each quart; and weigh the loss, where what went in and came out over a few batches gives your average cook loss. It's an ordinary Excel file with no macros, and it works in Google Sheets, LibreOffice and Numbers.
Where this stops working
Four soups, a run every Monday and Thursday, beans and kale from three suppliers, and a co-op asking about one quart. A sheet can say how much stock a run needs, but not which kale went into which run, whether it cooled in time, or how many quarts are left before their date.
How TaroStack does it
TaroStack keeps the recipe by weight, takes each batch's ingredients off stock and checks its yield.
The recipe in the units you use. A recipe holds each ingredient by weight, with beans bought by the 25-pound sack and used by the pound, and the cost of every quart comes from what you paid. "What could I make right now" says how many runs the beans, tomatoes and stock on the shelf allow.
Each run a batch. A run takes its ingredients off stock, records the lots of beans and kale it used, and gets a lot of its own for the quarts, with how much came out good, how much was rejected and the labor minutes.
Yield checked from history. From your own batch history, TaroStack says whether a recipe yields what it claims and which ingredient's quantity is off, so a cook loss that creeps up shows in the numbers. A case of kale that wilted is an adjustment with its reason, spoiled, and shows in the waste report.
| The job | Spreadsheet | In TaroStack |
|---|---|---|
| Ingredients for Thursday's run | Multiply, then check the shelf | What could I make right now |
| Which kale went into a run | Not written down | Lots recorded on the batch |
| The real cook loss | Weighed now and then | Good and rejected on every batch |
| Kale that wilted | Thrown out, forgotten | Adjustment with a reason |
Recipes, batches, lots and yield are on every plan, from $49 a month. The first 30 days are free, with no credit card. If you'd like a hand setting up, ask, and we'll do it with you.