Last week involved a trip to London, down before sunrise and back in darkness, not the most inspiring times for rail travel but the venue in the capital did more than justify the early alarm call.

My destination was the Portuguese ambassador’s house in swanky Belgravia, the reason, a small focused tasting of some 50 Portuguese wines selected on behalf of the commercial arm of the Embassy to highlight the present flight of wines that once struggled to gain International appreciation. I will detail my excitement regarding the ensuing discoveries next week in On the Grapevine. So the early start to the day, with four hours of travel interspersed with the concentrated task ahead, meant that the need for a simple breakfast or at least an authentic cup of coffee was high on the list.

Although our rail network from Norwich boasts improvement and the new ticket machines, un-commissioned at the time of writing, signal more modern and civilised rail travel, the catering facilities remain grim.

If you cannot compete with the wily and much rehearsed scrum that usually beats me to one of the restaurant car seats, as rare as hen’s teeth on the odd occasion they have coupled one on, then the only on-board alternative is that cumbersome food trolley clattering its way through the carriages like a French Revolutionary tumbril, its contents similarly desolate. Most mainland European trains offer fresh baguettes and salads as well as proper coffee, often on the lowliest of journeys, why do I get offered a tin of Pringles and a slab of fruit cake? Are they trying to gain a ‘highly commended’ at the EasyJet school of national cuisine? No, reluctantly one realised that some sustenance would have been found elsewhere to complement the rigours of a fourteen hour round trip.

After the tasting, which had coated the palate with dense rich reds and anaesthetized a few dozen taste buds, we head back to Liverpool Street Station a little jaded and in need of an epicurean lift. The further discomfort of pressing one’s face into stranger’s armpits and suffering what would otherwise be judged as sexual harassment in any other circumstance, we travelled in what is accepted as the greenest form of London travel – the underground rush hour.

But our interim reward was beckoning, a taste of that most cleansing of cuisines – Sushi.

Tucked away, upstairs at Liverpool Street is a fantastic fast food haven. The modest little restaurant known as Mushi Mushi with about twenty metres of scaletrix track zigzagging around the place and entering grotto-like tunnels in and out of the kitchen beyond, my reward was imminent. The one defining feature of Sushi is how quickly the natural world and the plate are combined. The purity with which a Japanese Zen kitchen can offer up its produce has almost no comparison anywhere else in the world. Food types are isolated rather than mixed and sauces are served as separate identities rather than amagamations. Observing the highly trained chefs preparing raw fish or the lightest of cooking techniques, one sees a spectrum of food creation so different from the norm of slow cooking and integrated sauces and ingredients found elsewhere. Presentation too plays a key role in the pleasures ahead with a minimalism only seen in Japanese art or traditional architecture. This approach was pretentiously and unsuccessfully high jacked by the way, in the mid ‘70’s in the form of Nouvelle Cuisine whereby French pomposity managed to overcome Japanese modesty with hilarious results.

If you can tolerate fresh raw-fish as a concept then the flavour range is myriad, a sort of colonic irrigation of the upper senses.

My eternal favourite is the neatly cut Nori Roll. Vinegar infused rice, (an early preservative of the crop), is laid along an oblong sheet of toasted Nori seaweed. Various fine slivers of raw fish, avocado or cucumber lay as a thin line of top and the whole thing is rolled, using a flexible bamboo mat with singular precision into a perfect green rod. The unit is cut five times providing six individual little taste bombs and presented with ultimate simplicity on a modestly decorated plate, the whole operation taking less than a minute. Alongside are the jewels to enhance, a bowl of laser-cut slices of pickled ginger, a little soy sauce and the wondrous accompaniment to clear the head and often most of the tear-ducts – wasabi paste, often nicknamed Japanese horseradish, it is in fact unrelated to our crop but resembles the cleansing ‘bite’ nevertheless, all coupled with a delicacy which is the essence of Sushi. An ice-cold accompaniment of Sapora beer and the day’s fogginess was cleared all for less than £20. Try getting colonic irrigation for that these days.