THE memory is as fresh as this morning's catch. A Mexican beach. Sleeping out under the stars. His two travelling buddies asleep in the car. His backpack tethered to the steering wheel. Stirring in the morning to find he'd been robbed of everything but the clothes he'd slept in, and realising that a deep sleep probably saved his life.

Rick Stein might shudder as he recounts the tale of his near thing as a young man travelling around Mexico, but it hasn't stopped him going back. The robbery, in 1968, was several lifetimes ago, but the 70-year-old restaurateur, chef and TV presenter tells it like it happened yesterday.

"I'd met a couple of English guys who had an American car and were driving through Mexico together," recalls the softly spoken Cornishman, casting back. "They slept in the car, a Dodge Dart, but there wasn't room for me, so I slept outside the driver's door and tied my backpack to the steering wheel.

"The bag was stolen in the night, with everything. All my luggage. I remember being so angry. We went to a cafe where we always used to go for breakfast – huevos rancheros, of course – and the guy there said I was so lucky I didn't wake up, because I would definitely have been killed. Some guy came up and cut the straps. We'd all slept through it."

Stein is sitting in a hotel suite in Glasgow's Blythswood Hotel, 15 minutes after arriving from a book promotion appearance in Edinburgh, and 45 minutes before his next one in Glasgow. He's spent the week touring the country, punting, signing and smiling, telling tales about going back to the country he first discovered as a directionless young man wandering the world trying to make sense of his father's suicide when he was a teenager.

The tour is in conjunction with his latest TV series, a foodie travelogue through Mexico and California, and the accompanying cook book, all glossy pictures of salsa and street stalls, wafting suggestively under our annual turn-of-the-year desire to eat better and travel authentically.

Maybe even both at the same time.

We meet at the hotel's door and slide past the restaurant where the

daily special is advertised on a placard outside. It's lemon sole. The seafood specialist's eye is momentarily drawn to the board the way a petrolhead might admire passing wheels, and we share small talk about the journey and his schedule, a road trip very different from the one he took as a youthful hitch-hiker on the Pacific coast.

"I did get into one or two dangerous situations in Mexico the first time," he says. "I remember hitch-hiking through one town and a mother and daughter stopped me and gave me money to get the bus because it wasn't safe. I did it anyway. One of the things I'm keen to point out is that it's generally not dangerous for tourists, but it can be bloody dangerous if you happen to be in the wrong part of Mexico."

Stein was 19 years old when his father, Eric, took his own life. The aftershocks eventually sent him travelling first to the Antipodes, where he spent a couple of years, then on to America on a whim and a cargo ship.

"My dad had committed suicide and the knock-on effect of that was that I ran away from my family in Britain and everything. I was taken with the idea of Australia, spent a couple of years there and came back via New York. It was just chance that I ended up in Mexico."

He'd been given a job working his passage on a boat from Auckland to New York. But having had his skin warmed by two years of Australasian sunshine, he didn't take to Manhattan's January chill.

"I was reading DH Lawrence's Mornings in Mexico at the time and it portrayed this country which was almost like the Mediterranean. I was freezing cold in New York. So I went to Mexico to get out of the cold. And when I got there I discovered the wonderful nature of the cuisine there. It was more than you could dream of in the 1960s in the UK, so immediate, all about chilli and salad and lime juice."

Turning 70 seems as good a reason as any to venture back along the Pacific Coast Highway, chasing the ghosts of his youth and the first tastes of that culinary epiphany.

The series, Rick Stein's Road to Mexico, is equal parts road trip and cookery lesson, a combo which has led to him becoming a key influencer away from the kitchen in the travel market.

"I keep winning little awards from the travel industry," he says, chuckling. "I find that really odd, because it's not what I do. I'm a chef. The number of people I meet on this book tour who tell me they've been to Copenhagen, Cadiz, Bologna, where I went on the last series [Long Weekends]. It's not like I'm selling anything. I was just there for the food, and saying what it feels like to be there."

But do people really watch food programmes to learn how to cook? Or are such shows more about vicarious culinary adventures on the sofa, where they compete with the lure of tea, chocolate biscuits and Twitter updates?

"A lot of TV is about people not really thinking that much, isn't it? That might sound a bit dismissive, but I was watching a thing the other day about glass blowing, and there are all these programmes now that are being made to be watched while you're doing something on your iPad or your phone. It's mesmerising, but it's just people blowing glass and making a jug.

"I think in one way people watch TV to switch off, but what we are doing is trying to engage people in some sort of intellectual way about food and the environment and history."

Though one of the world's most prominent seafood chefs, splitting his time between homes and restaurants in Australia and the UK, Stein is nevertheless encouraged by the grassroots food movement.

In the new series he visits food trucks in California, a hipster scran scene common to culturally adventurous pockets up and down the Pacific Coast, the transatlantic waves of which can now be seen at regular food-cart pods popping up in industrial units across Glasgow.

"There's a real atmosphere to these things and people are drawn to it," he says. "I think it's great. When I started my restaurant in the early 1970s, I did all the interiors myself. It took about £5000 to £10,000 to open the restaurant. Most of the stuff was bought at household sales and I did all the wiring and plumbing.

"Now if you're going to open a restaurant it's going to cost you £200,000 minimum. So of course young people who want to get into food are going to do it in a food truck or an old shipping container. I think that's exciting.

"My nephew is the DJ Judge Jules and I remember in the 1980s he used to find disused warehouses and other buildings and hold parties in there. And with some of the young people, it's the same thing. Where there's a will there's a way."

Is it rave culture for food?

"That's exactly what it is. I wish I'd coined that myself."

That one's on the house, chef.

THE democratisation of food, from pop-up pods to self-appointed grub gurus proselytising on social media about the latest cafe to do a vegan avocado sourdough toast, is a world away from the sweet and spicy world the young Stein faced in the 1960s when counterculture was more about getting free love than going gluten free.

Yet rather than rail against any notion of faddism, he welcomes the attention to detail people are paying to their food, and cooks up a theory which might have its roots back in the alternative thinking of a 1960s SoCal road-tripper.

"The plus side of emotional connection with food leads to special food in places like Mexico, special dishes at special times of the year, the same way it does for us at Christmas or Hogmanay," he says.

"In places like Mexico, China, Japan and India the connection between you and who you are not only emotionally, but physically and metaphysically, is really strong.

"But the other side of it, I think, is something to do with a lack of spirituality, the death of religion. I think we all need some way to express ourselves spiritually, and one of the ways of expressing physical dissatisfaction is to develop some sort of aversion to food.

"I might be speaking out of turn, but it's almost like when children are very little and say, 'I'm not eating that.'

"The net result of it is that it doesn't matter how it starts, it's real. One of the things I discovered in California is that everything that happens in California, good or bad, ends up happening here. And in California there is a big problem with food allergies.

"One of our fixers had food allergies. And all the places we went to took it seriously. It's a bit like psychosomatic illness. People can say, 'You're inventing that,' but it doesn't stop you feeling the pain. It's no good being sniffy about it. It's here to stay."

That said, is Stein spiritual about food?

"In a way," he says. "We just need things to rejoice in sharing with each other, because with the internet and all that people are on their own a lot of the time, and I think we were designed to be together.

"I don't believe in God but I have always thought that the religions that I know about have a wonderful way of bringing everybody together. The other side is they also have a wonderful way of getting people killed.

"I believe in the necessity to have customs, celebrations, a formal way of expressing our spiritual side."

Stein's new series might be rooted in the past, but in such open-mindedness the septuagenarian is hungrily embracing the mores of the day, in the church, the kitchen or around the dinner table.

He spent his 70th birthday in Hawaii with his sons from his first marriage and step-children (despite being a keen surfer, he says he's now "too old" for the waves), and flip-flop between Sydney and Cornwall each Christmas, co-ordinating with his second wife Sarah, his children and step-children.

Next month, it's Sydney.

"Contrary to what people think, most Australian families I know don't spend Christmas on the beach eating salad. They have turkey. And just because I'm a well-known cook, there's no chance of me doing the main course. I'm on the veg.

"So many families [have experienced] divorce and it's incumbent on you to try to make it as easy as possible. What's really nice for me is that my sons get on well with my step-children."

We meet in the week in which those in the culinary world mourned the loss of Italian chef Antonio Carluccio, a close friend of Stein's, and he's keen to pay tribute to him.

"I was really fond of him and I'm very sad he's gone," he says. "I could talk to him about the intricacies of Italian cooking, the importance of raw materials and cooking the right things at the right time of year.

"What slightly pissed me off is that I went to his 80th birthday party a few months ago and told him how very happy I'd be if I looked as incredibly well as he did at 80. And then, blow me, he goes and falls over. It's a sad thing."

Stein is conscious of time, having no intention of cashing in his chips. Filming the new series he met a sea-urchin fisherman the same as him in California and asked him whether he was "a bit long in the tooth for this".

As we walk to the book shop where a queue of fans awaits him, I ask him the same question.

"I think if you enjoy something and can still do it, then do it," he says, in the spirit of a twentysomething road-tripper who once dodged a bullet on a Mexican beach. "I've no intention of retiring. I've friends who say it's wonderful, but I'm very happy with what I do. And I'm still learning. A lot of journeys we take are journeys of discovery and we never know where we'll end up. So I'll keep going."

Rick Stein's Road to Mexico is on BBC Two, Tuesdays at 9pm. The accompanying book is published by BBC Books, priced £26