The first day of President Trump’s UK visit was full of fluff.

We draped ourselves – and the president – in the sort of pomp and circumstance that makes the British and its royals a source of global curiosity. There was the 41-gun salute, the stilted walk beside the Queen in the grounds of Buckingham Palace and the lavish state banquet in the evening, Ivanka decked out in what can only be described as 1950s housewife chic.

But today comes the serious stuff, as the president and his advisors sit down with our Theresa May and hers, talk of forging a free trade deal post-Brexit undoubtedly high on the agenda. A conversation free of fluff, I’d wager, but chock-full of feathers.

No FTA between the US and UK will be agreed without a rethink on food. As many of those close to Trump have insisted, nothing – not even our NHS – is ‘off the table’.

Under EU laws, all manner of US produce and products are currently restricted, from soft drinks laced with BVO (brominated vegetable oil) to cookies dusted with potassium bromate flour (reportedly to give them a ‘glow’). But no US practice has quite caught the imagination of we Brits like the prospect of chlorinated chicken.

The practice of bathing processed chickens in a chemical wash, often chlorine, to strip them of disease, is commonplace in the US. But here it has caused unprecedented outrage, evolving into a sort of shorthand for those pointing to the backward step Brexit represents for our food standards.

As last night’s Dispatches investigation equivocally demonstrated though, those that get stuck on the chemicals rather miss the point. In fact, what undercover reporters found at a Tyson Foods processing plant in the US left me longing for chlorine. Bleach even. Anything to wash away the sight of bloody bits of chicken carcase being swept into blocked drains, innards stuck in the production line, and workers piling up trays of raw poultry haphazardly, one on top of the other.

At one point, staff were called to a company briefing after one worker had three fingers amputated using a machine they hadn’t been trained on – one of 70 serious injuries over a 21-month period. They were also reminded that sticking bits of glass in a chicken was a federal offence.

It was a snapshot of a huge poultry production line of course, the US producing no less than nine billion chickens each year. But it was also a shocking reminder that the use of chemical washing is necessitated by far graver health and safety problems higher up the food chain – something our politicians would do well to remember as they attempt to woo the president today.

No amount of pomp and circumstance can cover up the sort of ugly reality they’ll need to grapple with in upholding the integrity of our supply chain. And no amount of chemical – chlorine, peroxide or otherwise – can wash away that level of institutional grime.