Knowing when to change cooling oil is a critical decision, affecting both food quality and cost.
The most common method of testing the quality of cooking oils has been the Free Fatty Acid test, which can only be conducted by a trained scientist in a laboratory setting.
However, the Testo 260 cooking oil tester can be used in the kitchen. It tests a small sample of oil and gives it a red or green light in seconds. Red means change the oil; green indicates that the oil is still usable.
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