An evening of jazz prefaced by serious chat about global food security doesn’t sound an obvious combination, but if anyone can pull it off, it’s Jay Rayner.

The restaurant critic, author and amateur pianist is uncharacteristically nervous about hosting – and playing – at JW3 next month.

“It’s a double header, a one-man show with talk and jazz and requires complete chutzpah to think people will come for two and a half hours of me.

“But there will be jokes and interaction, it won’t be death by PowerPoint.”

He has surrounded himself by “seriously good musicians – the top of the tree” for the programme of jazz standards, and will bring the same witty, incisive turn of phrase to the patter as he does to his Observer restaurant columns.

The chat is based on his book, ‘A Greedy Man In A Hungry World’, part dissection of the challenges of feeding a growing planet, part food memoir about growing up the son of agony aunt Claire Rayner.

It demolishes middle-class tropes about eating virtuously by buying local, seasonal, organic produce.

“The idea that this way of eating will save the planet doesn’t stand up to examination.

“We have been fed a story which supports a lifestyle, that comes with a thin veneer of self-righteousness about being a good person.

“I love farmers’ markets but they are no challenge to the supermarkets and, indeed, it’s not practical for most people to avoid supermarkets.”

Rayner calls for a realistic global understanding of food security – how the growth of the Chinese and Indian middle classes will have more impact than Brits buying organic.

Buy British

Although one of his conclusions is we should pay more for our food and buy British: “Not for patriotic purposes but to shore up our own food security and self-sufficiency”.

And what of the morality of Londoners paying hundreds of pounds in top restaurants?

“Expensive restaurants are wasted on the people who can afford them, botoxed coked-up monstrosities who don’t care about food, but I am not going to criticise someone who saves their money and instead of spending it on a ticket to the football, rugby or opera, goes to good restaurants for their leisure activity.”

As someone with a “Jewish cultural identity”, he likes that JW3 can also appeal to “cultural Jews who just want to talk about Woody Allen and food.”

Dubbed ‘acid Rayner’ for his withering judgements of substandard restaurants, his review of JW3’s Zest was among the most effusive he’s ever written.

“As a godless Jew, I am deeply suspicious of a god who is such a picky eater and hands down rules of what you can’t eat. Too often kosher food ends up as some sort of compromise.

“This was Sephardic food which I happen to love, but fresh, sharp and vivid with no compromise.”

When writing his column, he continually reminds himself: “You are not selling restaurants, you are selling newspapers”.

“There are lots of people who know more about food, I’m hired for how I write, I do the eating for free.

“You need to be engaging and recognise that food can take you anywhere, into other parts of your life.”

The 47-year-old once worked for the Ham&High for three months as a sub-editor and theatre critic, but says the job put him off the stage.

“I find it easier to sit through a bad meal than a bad play because with theatre you have to do it alone. Being a restaurant critic has never put me off. Even now I still take huge pleasure from restaurants, however bad. I love the moment of anticipation when someone brings me a list of things to eat.”

That said, he goes to the gym four to six times a week to counter the calorie-laden meals: “I am a greedy bastard, you can’t be a ridiculously picky eater and a restaurant critic – you have to put greed in there as one of the qualifications, and when shaking down a menu, you have to go for it.”

Jay Rayner is at JW3 on March 25. www.jw3.org.uk.