“Dingalingaling!” cries Heston Blumenthal excitedly. It sounds like the UK’s most high-profile culinary alchemist has an idea for a new and boundary-pushing dish. In fact, he’s recreating the sound made by the bell of a sweetshop off London’s Edgware Road.

“I remember it really clearly,” he says. “As a kid, the sweetshop was the first time when you felt like you had some responsibility. Your mum would give you some money, and you’d go through the kiddieconomics of working out what you could afford. The gum-type candies were cheaper, but you could blow the lot in one hit with a bar of chocolate. I loved chocolate.”

Nostalgia runs through Blumenthal’s culinary philosophy like liquorice through an allsort. The Fat Duck, his world-renowned three-Michelin-starred restaurant, even includes on its Tasting Menu “Like a Kid in a Sweet Shop” - a striped paper bag full of very superior confectionery.

And now his new series, Heston’s Fantastical Food, allows him to indulge in nostalgia on a mind-bogglingly large scale. In it, he revives a clutch of food experiences that are in various states of decline - such as stopping work for a tea break, having a pie and a pint, or buying a 99 from an ice-cream van. But he’s doing so on a vast scale, constructing giant “dunkgestive” biscuits and oversized pork scratchings and inviting locals to come and taste a piece of the action.

Today we’re in Chesterfield for sweetshop day, surrounded by mammoth tubes of sweeties and a magical confectionery garden. “Food rituals and experiences can bring a community back together through nostalgia and excitement,” he says, and to prove it, like Willy Wonka, he’s giving away golden tickets to the garden.

Collective memory is key to Fantastical Food. “We produced some great things in the Feasts series”, says Heston of the Channel 4 shows in which celebrities oohed and aahed at his edible candles and frog blancmange, “but the criticism was you’ve got invited guests, well-known people. What about the general public? Why can’t we take part?”

“That was one of the big things for Fantastical Feasts: we thought, ‘Let’s do that.’ For each experience and food, we’ve found a town with a link to them. Chesterfield is where the Trebor sweet factory was, and it got pulled down. A lot of people in this town worked for years in the factory. An iconic mass-produced food brought together a community and is no longer there. All you’re left with in that community is the memories. For one day, we’re able to bring those back.”

Each of the themes (he’s also celebrating the packed lunch, breakfast, and the flavours of Christmas) has meaning for the chef, although it’s the childhood ones that really resonate.

“Each one is quite personal. I think it has to be; it has to have that level of nostalgia, but bring everybody else along. We’re bringing back what the experiences did to you as a kid, and I don’t think we ever lose that as adults. Some of us build barriers and cover our inner child in all sorts of other issues, but I think most adults love being kids again and the excitement that can bring.”

Blumenthal, who is 46, grew up in the 1970s. Childhood has changed since then. “Kids now have computer games to play, so while ice-cream vans, for example, hold excitement, it’s not the same as it was. The decline of the vans is down to a few things: the effect of supermarkets, health and safety  - they can’t play the chimes for more than four seconds - and, because they’re limited in where they can go, they need to be really busy to warrant a £40,000 ice-cream van.”

What, I ask, would be wrong with a world without ice-cream vans? He shudders. “What? The essence of this for me is that we don’t use nostalgia enough in food. Memory is so powerful. The experience, the context of food in some shape or form can be so exciting and make us so happy. If we denied ourselves those feelings, the world would be much worse off.”

“Smell is the biggest trigger of memory of all of the senses,” says Blumenthal. “For instance, there are two smells that say Christmas to me. One is orange and a mixture of spices: cinnamon, cloves, nutmeg and anise… a bit like pot pourri with dried orange slices. And there’s a particular type of pine, Douglas fir, that reminds me of a close friend of the family who had a really cosy house with a red leather chair and a fireplace. We used to go and see him a few days before Christmas and the smell of Christmas tree takes me straight there. I sourced an incredible pine resin essential oil from Provence, which we use in various things. I once made some goose feed with pine essential oil, to see if we could make a goose taste of Christmas tree. It didn’t really work, but for the Fat Duck Christmas menu we’re doing some poached meringues with Christmas tree flavour.”

But if Christmas is still a fixture in our lives, it’s the lost collective food experiences that make Blumenthal sad. The ritual of the tea break has also, he says, fallen by the wayside. “In chef world the tea break doesn’t really exist because you’ve got to crack on, but when I was younger I worked for a photocopier company. In the office everyone stopped for a cup of tea. You have a chat, catch up. I haven’t had that for years.”

“In Darwen in Lancashire, one of the centres of the Industrial Revolution, there are no factories any more, but there are people who worked in those factories who remember the benefit of the tea break. We wanted the whole town to have one, so we tried to do a tea break with the largest teabag and teapot in the world. On the day, the mayor of Darwen ended up dunking a giant biscuit with a guy who’d worked at the same factory as he had. They hadn’t seen each other for 50 years. They were more or less crying.”

Blumenthal had less success trying to persuade commuters to sample his breakfast. “It’s a bit like the tea break, with the family coming together round the table every morning before work. But now people tend to get up as late as they can to get on a crowded train, drinking out of a cardboard cup. So we laid on this crazy big breakfast at a commuter station in Birmingham, at half six in the morning. I must have asked 100 people, maybe more, and I’d say that half of them didn’t even look up. It’s as if someone had put them on automatic pilot. They just weren’t talking to anyone.”

“The plan was to create a breakfast experience with elements of sensory stuff around you: a chicken cock-a-doodle-dooing, the sun streaming through the window, the smell of the coffee. We used yoghurt jelly with mango puree to make a giant boiled egg, and pressure-cooked baked potatoes to look like baked beans. Some of the people that looked up did a double take, and said, ‘I’d love to, but I’ve got to go to work.’ We managed to get three people to try it and in the end it was the people from the train station that came.”

Building giant food that also tastes good - the intention is that no crumb goes to waste - is the kind of technical challenge that would make a grown man weep. “TV programmes have done big food before, but a massive pizza or a massive paella can be disgusting. We wanted to make big stuff so that it engaged people. It’s really important that they eat it, and that brings them together. They get to try some delicious food that’s really pushing the level of surprise and excitement, and get right behind it. None of the food goes to waste. One of the challenges with big food is that, by its nature, the weight bearing down on the bottom part of the food is very heavy. If that food has to be strong enough to support itself, you can’t eat it. It defies physics.”

In Gloucester, 3,000 people turned out to see Blumenthal serve his one-ton ice cream, complete with a three-metre cone and five-metre chocolate flake. His inner science geek comes bounding to the surface. “The ice cream we made took a month and a half to freeze. You’ve got to think about freezing and heat transfer. If we transport the ice cream to go on top of the cone, it has to be craned on. What happens if it melts? When it’s that size, with so much cold mass inside, the outside will start to melt while the inside’s too hard to scoop out. We had to think about the way we made the ice cream and the amount of air we incorporated into it.”

His giant “dunkgestives” also called for big thinking. “We looked at the psychology of dunking. We went to Nottingham University and did some flavour profiling and flavour release tests on which biscuits were good for dunkability. We got a genuinely good scientific discovery, X-rayed the biscuits, and put that all in the biscuits we built for a big dunk.”

Thousands turning out to see Heston and his flake, golden sweetshop tickets distributed to the people of Chesterfield, grown men tearing up over a cuppa – it’s all lovely, but it’s unlikely to resurrect these rituals. Or is it?

“Here in Chesterfield, I walked down the street with no cameras, and it was amazing. People were running out of their doors, out of estate agents, banks and newsagents, to tell me how excited they were about what we were doing,” enthuses Blumenthal.

Would they be just as excited if an old-fashioned sweetshop opened? “After doing something like this, if they’d been touched by some of the magic of it, yes. I think they would.”

Heston's Fantastical Food starts tonight at 9:00pm on Channel 4