Frying oils quality factors

In a commercial restaurant, the measurement tools need to be fast, consistent and simple enough for the fryer operators to be able to handle properly. Obviously, the most logical end point of oil is when the fried food starts showing signs of deterioration in sensory attributes (taste, appearance or texture). The challenge is that sensory attributes are somewhat subjective and not easy to measure in an objective and consistent way by multiple operators. The quality and skill level of the staff and operators can also become a limiting factor in terms of managing the oils to their full potential. 

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