Arithmetic
Calculators
Seven calculations, each with its working shown and each checked against a published figure rather than a remembered one. None of them is a black box, and none of them will tell you a preparation is safe.
9 CFR 424.21 and 424.22
Ingoing nitrite
Parts per million of sodium nitrite going into the meat, from the mass of cure mixture, its stated nitrite content and the green weight, checked against the limit for the product class.
Equilibrium cure and equilibrium brine
Salt percentage
How much salt to weigh out for a target percentage, dry or in a brine, and what strength that brine starts at.
FSIS formula
Brine concentration
The FSIS measure of how salty the water in a product is, which is the number the S. aureus and dry-cured ham thresholds are stated against.
9 CFR 319.106(b)(7)
Dry-curing weight loss
Percentage lost against the green weight, and the weight a piece has to reach for a stated target.
FSIS-GD-2014-0010
Water activity and shelf stability
Which published shelf-stability limit a given water activity and pH meets, and the moisture-protein ratio alongside it.
FSIS-GD-2023-0002
Degree-hours
Hours above 60 F multiplied by the degrees above it, accumulated until the product reaches pH 5.3, which is the accounting FSIS uses to limit Staphylococcus aureus growth during fermentation.
FSIS-GD-2016-0002
Trichinella drying schedule
Days in the drying room for a sausage, from the casing diameter, with the published reductions for a warm hold beforehand and the published increases for reduced salt.
The occasional dispatch
When a regulation changes, a guideline is reissued or a new protected name enters the register, it goes out in an email. Occasional, not scheduled, and only when something actually moved.