Food Cold Chain MKT Calculator

Many chilled foods target ≤ 5 °C (some jurisdictions specify ≤ 4 °C or ≤ 8 °C for specific products); food safety law usually sets a maximum chill temperature rather than an MKT. The authoritative limit is whatever your product's labelled storage condition and stability data specify — read it off the marketing authorisation, the manufacturer's storage statement or the governing pharmacopoeia, and enter your real temperature history against it.

No — food safety decisions follow absolute temperature/time limits set by food law (e.g. a maximum chill temperature and the time food may spend in the danger zone), not a kinetic average, because pathogen growth depends on actual time at warm temperatures. A brief warm spike that passes on MKT could still have allowed unsafe bacterial growth. Use MKT for quality and shelf-life comparisons (it correlates well with chemical/quality degradation and is handy in supplier cold-chain disputes), but make safety calls against the statutory maximum-temperature and danger-zone-time rules and your HACCP plan.

Because degradation is not linear with temperature — it accelerates roughly exponentially (Arrhenius). A simple average treats an hour at 30 °C the same as an hour at 20 °C either side of 25 °C, but the product is harmed far more by the hot hour. MKT weights each reading by exp(−ΔH/RT), so it reflects the true cumulative chemical stress. It is always ≥ the arithmetic mean, and it is the figure regulators expect for storage and distribution compliance.

Use a representative series with durations — typically the logger's interval readings, or summarised blocks of 'X hours at Y °C' if you only have an excursion summary. The more granular the data, the more accurate the MKT, but the result is dominated by the warm excursions, so capturing those accurately matters most. Don't average data before entering it — that defeats the point; enter the temperatures and let the calculator do the kinetic weighting.