When it comes to consumer conservatism I don't think I can really count myself among the world's militants. Yes, I was shocked when Kit-Kat announced it was going to abandon foil wrappers for a lifeless plastic sheath, thus depriving us of the pleasure of pressing a thumbnail into the furrow and slicing a neat slit through the silver paper. But the change came and went without any noticeable blip in my already modest rates of Kit-Kat consumption. And, although in theory I cherish the idea that Radio Four begins the day with a medley of English folk tunes, in defiance of the bullying hegemony of rolling news, in practice it could have been axed years ago without me even noticing.
But I did feel a surprising jolt of resistance when I heard that Marmite plan to market a less viscous form of its product in a squeezy bottle. Judging from the wild cry of pain from my colleague Philip Hensher the other day, I wasn't the only one. As I understand it, things aren't quite as bad as he assumed. Marmite traditionalists will still be able to buy the pot-bellied glass jar and the substance they pull from it will be as gluey as ever - but even that knowledge can't quite soothe the sense of cultural affront. The squeezy bottle will be out there, adulterating the cherished Marmite gestalt.
As any Marmite lover knows, you can't separate Marmite from its jar - often literally. Chasing the concavities of that stubby container for the last scrapings of brown goo is one of the rituals of its consumption - but there will always remain a few spots, under the shoulders of the jar, which are out of reach of the knife tip. And somehow the perversity of this packaging - in a world of ergonomic logic - is oddly satisfying.
The jar delivers other pleasures too: the aromatic poke in the nose as you twist the lid off; the glossy abstractions of light on that buckled, brown sheen, misted here and there by a slick of butter. Consuming Marmite is a ceremony of extraction not extrusion.
The obvious riposte to all this is "Get a life". To which you could reply that any definition of life that didn't include such humble gratifications would be a very poor thing. This is what life is made of, after all - not grand abstractions but the sensory rubble of everything we encounter, appealing or infuriating. And what's more, any definition of culture that couldn't find a place for Marmite on the shelf would be distinctly thin as well.
Arguing for a broader definition of culture than Matthew Arnold's notion of "the best which has been thought and said", T S Eliot - in Notes Towards a Definition of a Culture - famously compiled a list to illustrate the sort of thing that he thought might be covered by the word. Alongside the music of Elgar, Henley Regatta and 19th century Gothic churches he included " Wensleydale cheese" and "beetroot in vinegar". "Culture may even be defined", he wrote, "as that which makes life worth living".
It is, to put it in a way that is particularly apposite to Marmite, what adds savour to mere existence. Man can not live by bread alone - he needs, from time to time, to toast it, spread it with butter and then add something that tastes like a yeast cell's unwashed underpants - and by means of that be reassured some things in life are as they always were.
Obviously Marmite is never going to be one of the big structural building blocks of the culture but, for many Britons at least, it is a part of its interstitial material - something that blocks the chinks in the wall so that we feel sheltered from the steady, cold wind of the alien and the novel. It's why expatriate communities almost always ensure that they have a supply on hand and it's why we feel a secret thrill of pleasure when foreigners can't handle it.
There's surely a connection too between the relatively unchanging shape of the jar and the apparently fixed taste of its contents. Most of us are introduced to Marmite before we can even talk. That's why it arouses such passionate distrust of change from its devotees, because it has inscribed itself into that part of our characters which - whatever our electoral politics - is conservative through and through. The long survival of the jar - amid the Maoist permanent revolution of rebranding and product redesign - is inextricably part of that. And if you're one of those who loathe the stuff, that's all to the good as well, provided that you have a proprietory sense towards your loathing. Eliot also wrote in his essay of "the vital importance for a society of friction between its parts". So, you hate it if you want to - just don't change it.