Is This Cooking Oil… or ENGINE Oil?!

Understanding Oil Degradation in the Professional Kitchen

In this critique, Chef James Makinson reacts to an alarming viral video featuring a cooking medium so dark and viscous it closely resembles used motor oil. While framed as a humorous piece of online content, the visual shock of degraded oil raises critical professional questions regarding frying medium management, oxidation, and food hygiene standards. For any chef, maintaining the integrity of frying oil is not just a matter of flavour preservation, but also of fundamental safety and operational efficiency.

When cooking oil is subjected to prolonged high temperatures, it undergoes several chemical changes: hydrolysis, oxidation, and polymerisation. These processes break down the triglycerides, releasing free fatty acids and creating polar compounds. The visual result, as highlighted in Makinson's reaction, is a dramatic darkening of the oil, an increase in viscosity, and a drastic lowering of the smoke point. Using oil in this advanced state of degradation ruins the texture of food and poses serious health risks.

Identifying and Preventing Frying Disasters

To avoid serving food cooked in what looks like "engine oil," culinary teams must establish strict oil quality management protocols. First, visual checks are essential, but they must be backed by objective testing. Chefs should monitor the oil’s viscosity, smell, and smoke levels during service. When oil begins to foam persistently or produces a harsh, acrid aroma, it has passed its usable life and must be discarded.

Preventative maintenance is the best line of defence against rapid oil breakdown. Kitchen teams should regularly skim debris from deep fryers to prevent carbonisation, which accelerates oil darkening. Furthermore, filtering the oil daily—or even twice daily in high-volume settings—removes microscopic food particles that contribute to degradation. Implementing these simple back-of-house habits ensures a high-quality finished product and prevents the shocking kitchen disasters highlighted in viral media.