How to read a ghee laboratory report
5 min readUpdated
A ghee laboratory report is a set of measurements for one batch. Moisture and free fatty acids show how well the ghee will keep, the peroxide value shows how fresh it is, and the Reichert-Meissl and Polenske values help show whether it is real butterfat or has been mixed with other fats.
Why a report for the batch matters
Ghee differs from batch to batch with the milk, the season and the method. A report for the batch you are buying tells you more than a general promise on a label. Look for the name of the testing laboratory, the report number, the test date and any accreditation the laboratory holds.
Moisture
Moisture is the water left in the ghee after it is cooked. Water allows microbes to grow, so lower moisture means the ghee keeps better. Food standards usually set a low upper limit, commonly around half a percent for ghee.
Reichert-Meissl value
The Reichert-Meissl value measures small, water-soluble fatty acids that are characteristic of milk fat. Genuine ghee has a relatively high value, and a low value can point to dilution with other fats. The expected figure depends on the animal, the season and the region, so compare it with the standard named in the report rather than with one fixed number.
Polenske value
The Polenske value measures a different group of fatty acids that do not dissolve in water. It is used alongside the Reichert-Meissl value to help detect fats such as coconut or palm kernel oil, which raise it. Genuine ghee has a low Polenske value.
Peroxide value
The peroxide value shows the early stage of oxidation. Fresh ghee has a low value, and it rises as the ghee is exposed to air, light and heat over time. It is a useful signal of freshness.
Free fatty acids
Free fatty acids form when fat breaks down, and a high level is linked to rancid flavour. They are often reported as a percentage, and lower is better.
Adulterant tests
Many reports also include a result for tests that look for foreign fats or starch, usually as a pass or fail. A clear result here is an important part of the report.
What a report cannot tell you
A report does not describe taste, aroma or the way the animals were kept, and it only describes the batch that was sampled. That is why a report should come from an accredited, independent laboratory and be tied to the batch number printed on the jar. Every product page on Shuddha Ghee Nepal that has a published report shows these values next to the batch.