Oliver made the headlines for his war on school dinners

Viewers complained to the organisation after Oliver made several references to his Flavour Shaker and demonstrated it during the Jamie At Home series.

Ofcom ruled that two episodes breached strict guidelines forbidding "undue prominence" to products or services.

Channel 4 said the references were "unduly prominent", but justified.

The broadcaster added that it would scrutinise programmes brought in from other companies more closely.

'Insufficient justification'

Jamie At Home was made by Fresh One Productions, the 32-year-old chef's own programme-making company.

In one of the shows in September, Oliver referred to the utensil by name before spending two minutes demonstrating how to prepare an oregano oil with it.

There were also several close-up shots of the item, used to make marinades, and further references to it in an edition shown in October.

But in the September programme, Oliver did tell viewers that they could use a food blender or pestle and mortar to prepare the oil instead of his branded utensil.

Ofcom ruled there was "insufficient editorial justification for how the Flavour Shaker was referred to and shown on screen, and rapped Channel 4 for failing to "ensure full editorial control over the content".