Soft Polenta with Mushroom and Tomato Ragù: where the numbers come from

Per ingredient

Oxalate

47 mg per serving (189 mg for the whole recipe, divided by 4). This comes from the Oxalosis and Hyperoxaluria Foundation list rather than the Australian composition data above, which does not carry oxalate.

Passata

The OHF lists no passata. Canned tomato is used, which is the same fruit strained.

Mushrooms

The OHF gives no raw mushroom row; the cooked figure is used.

Water

Tap water carries no oxalate: oxalate is a plant metabolite and drinking water is not a plant.

Oxalate in a plant moves with variety, ripeness, soil and cooking, and what you absorb depends on the calcium eaten in the same meal rather than on the figure alone. The full table and what it is worth.

Not counted

These lines contribute nothing to the figures above, because they carry no weight or no composition match. Finishing salt and pepper added to taste are deliberately excluded: the amount is the cook's, so counting it would be inventing a number.

• Ground black pepper, to taste

Why these records

Where a generic database item cannot represent an ingredient exactly, the choice is recorded with the ingredient rather than left to inference.

Fine Quick Cooking Polenta

Weighed dry before it is rained into simmering liquid; the uncooked cornmeal record applies because the cooked record already includes absorbed water.

Mushrooms

Weighed raw before being cooked down; ledger key carried over verbatim from the published book.

Onion

Weighed raw and peeled before it is softened in the pan; ledger key carried over verbatim from the published book.

Carrot

Weighed raw, peeled and sliced or grated, before any cooking; ledger key carried over verbatim from the published book.

Garlic

Weighed or counted as raw peeled cloves before cooking; ledger key carried over verbatim from the published book.

Passata

Measured straight from the bottle as strained tomatoes; the commercial tomato puree record is AUSNUT's closest equivalent, as there is no passata entry and the canned whole tomato records include undrained juice.

Tomato Paste

Recipe lines say tomato paste without qualification, unlike the site's explicit no-added-salt-canned-tomatoes ingredient, so ordinary added-salt paste is the honest reading and the more conservative sodium choice at 630 mg versus 36 mg per 100 g.

Olive Oil

Measured from the bottle, plain or extra-virgin; AUSNUT has a single olive oil record and the ledger key is carried over verbatim.

Dried Oregano

Weighed dry from the jar in 1-3 g amounts; ledger key carried over verbatim from the published book.

Parmesan

Weighed as a hard cheese and grated at the point of use; the fresh parmesan record matches the ledger canonical and is preferred over the dried finely grated record, which is far more concentrated.

Water

Contributes no energy or nutrients but mapped honestly rather than skipped; tap water is what the recipes use, and the ledger left this unkeyed.

Milk

Measured as fluid cow's milk with fat level unspecified, so regular fat is taken per the house rule; ledger key carried over verbatim from the published book.

Salt

Weighed or added to taste from the packet; iodised table salt matches the fine salt the recipes specify, and the ledger key is carried over verbatim.

What this is and is not

These figures match the ones shown on the recipe page exactly, because both come from this same arithmetic.

A composition database gives representative values for a food, not an analysis of your tin, your loaf or your cut of meat. Brands differ, produce varies, and yields change with how long something cooked and how hard it was drained. Treat every figure here as an estimate of the right order rather than a measurement, and where a number matters clinically, take it to whoever is managing your care. CERNERE publishes the working so it can be argued with, not to imply a precision food does not have.