London, Aug 25 - Popular chef Jamie Oliver started hallucinating after chewing an ingredient on his cookery show 'American Road Trip'.

Mirror.co.uk reports that on the show the 34-year-old was looking for recipes in a Mexican immigrant community in Los Angeles. A market girl gave him a dried brown substance, cactus fungus, and told him to 'chew it later'. But when he put it in his mouth, he said it 'tastes like sh*t'.

But a few minutes later he squinted his eyes and said: 'I think that stuff is sending me slightly mad. I'm starting to hallo, hullca... I can't even say it. I'm hallucinating.'

He then began to sing strangely and before leaving the market he said: 'I'm getting a little bit trippy.'

On his six-part US adventure he also encounters several other bizarre foods, including chopped cactus spikes. 'American Road Trip' will go on air next Tuesday on Channel 4.