Raw, thermized and pasteurized milk: three words that decide whether a cheese can enter

Buyers of Italian cheese see these three words at the bottom of a data sheet and tend to read them as a process detail. They are not. They are the line that decides, before any commercial consideration, which countries that product can enter and on what terms.

Three categories, defined by a number

Raw milk. Regulation (EC) No 853/2004 defines it as milk produced by the secretion of the mammary gland of farmed animals that has not been heated to more than 40 °C nor undergone any treatment with an equivalent effect. The definition says nothing about quality: it sets a temperature threshold.

Pasteurized milk. A heat treatment which, under the European hygiene rules, has to leave the product giving a negative reaction to the alkaline phosphatase test. It is an indirect but practical check: the enzyme is inactivated at conditions close to those of pasteurization, so its absence is evidence that the treatment took place.

Thermized milk. It sits in between, and it is the category that causes the most confusion. It is a heat treatment below pasteurization: it reduces the microbial load without reaching pasteurization conditions. The operational consequence is that thermized milk stays phosphatase-positive. On the same test, it is the exact opposite of pasteurized milk.

Why the distinction matters in the cheese

A heat treatment does not act only on unwanted organisms. It acts on the whole microbial population present in the milk, including the part that takes part in aging.

How varied that population is in raw milk has been measured. The paper published in SpringerPlus on August 27, 2013 analyzed the fungal flora of raw milk from Italian summer pastures at different elevations and found diversity rising with altitude: at the highest pasture in the sample, 2,200 meters, seventeen species were isolated. In raw milk cheese that population is not a leftover: it is part of the equipment.

From this follows the commercial consequence, which is worth stating without rhetoric: raw, thermized and pasteurized give products that behave differently in the cellar and on the shelf. It is not a scale from worst to best. It is a technical choice with different effects, and it should be known before buying rather than discovered afterward.

Where it becomes an import problem

In the United States the base rule is 21 CFR 1240.61: milk and milk products intended for direct human consumption may not move unless they are pasteurized, except where a regulation provides an alternative procedure. For cheese, that alternative sits in Part 133 and always says the same thing: if the milk is not pasteurized, the cheese has to be cured for at least 60 days at a temperature no lower than 35 °F (1.7 °C). The wording appears in the standard for each family — 21 CFR 133.150 for hard cheeses, 21 CFR 133.182 for semisoft.

The rule applies identically to imported product. It is not a question of how good the cheese is: it is a condition of admissibility.

The most expensive mistake: treating thermized as pasteurized

This is the error seen most often, and it is understandable: thermized milk has been heated, so “it is not raw”.

For the purposes of the US rule, however, what counts is not that the milk was heated. It is whether it reached pasteurization conditions. A thermized milk cheese should be treated as unpasteurized, unless the actual treatment has been documented and verified. With 45 days of aging, a product that is perfectly compliant in Europe does not enter the United States.

The cost of that mistake is not a fine. It is a shipment held, a customer waiting, and a selling season lost.

The line not to cross when selling

There is one last point, and it concerns the copy the importer will write for their own market.

The distinction between raw, thermized and pasteurized is a process fact: it says what was done to the milk. In commercial communication that fact often gets turned into a wellbeing argument — more natural, more alive, healthier. That is the moment where saying how a product is made turns into promising what it does to the person eating it.

That step is not a nuance of style. In many markets health-related statements are allowed only if authorized and listed, and cheese does not appear on those lists. In some countries the penalties for misleading food advertising reach into criminal law. A sentence written in good faith by a reseller can cost more than the goods.

The working rule is simple, and it applies to the material a supplier provides as well: describe the process, do not promise an effect. Milk type, days of aging, temperature, format, weight. All of those are verifiable, none of them needs authorization, and they hold up in any market.

If the end customer wants to understand why two cheeses of the same type differ, the honest answer is technical: different milk, different microbial population, different time. It works better than an adjective, and it exposes nobody.

What to ask, item by item

Not by product family: by individual item, because processing can differ inside the same family.

1. Is the milk for this item raw, thermized or pasteurized?
2. If thermized, is there documentation of the actual treatment — time and temperature — and of the phosphatase test result?
3. How many days of aging does the batch have on leaving? The real days of that lot, not the specification minimum.
4. How many days pass between dispatch and customs clearance? What counts is aging completed.
5. Is the figure written on the documents travelling with the shipment? A verbal answer clears nothing.

The point

The three words do not describe a level of quality. They describe what was done to the milk before cheesemaking. That fact has two independent consequences — one on how the cheese behaves as it ages, one on its right to enter a given country — and the two should not be confused.

For an importer, the second comes first. A product that cannot enter has no characteristics. It only has a cost.