And when I quietly asked one of the other Americans if she could actually taste anything, she conceded the effect might have been more than a bit psychosomatic.
From their first-time visitors' perspective, New Zealand is still 100 per cent Pure.
You can't buy that kind of international reputation. But poison our natural habitat and you can spoil it pretty fast.
I've eagerly anticipated National and Labour's respective election policies for freshwater protection and management.
The first part of Labour's new water policy chases an easy win. Charging companies that bottle and export drinking water is popular with the voting public.
But as I've reiterated in this column before, the bottled water export industry is a side show compared to our biggest water extractor, and Labour's plan to charge commercial irrigators is much more impactful and contentious.
According to the Ministry for the Environment, we extract 600,000 times more water for irrigation than the amount of bottled drinking water we send overseas every year. Farmers point out that with our plentiful rainfall and water resource, it's still a relatively small amount.
But that ignores the startling impact that dairying in particular is having on our environment.
New Zealand has more than twice the number of cows than 40 years ago.
Even the Minister for Primary Industries, Nathan Guy, foresees a point in the not-too-distant future where we reach maximum cow.
As the impact of dairying on our environment becomes more obvious, no one is suggesting for a moment farmers haven't put in a big effort. They've invested hugely to fence off waterways and you'd be hard-pressed to find a Kiwi farmer who doesn't appreciate the importance of protecting their land.
But given the extent to which our waterways are degrading, it's clearly not enough.
Short of taking cows out of paddocks and sticking them all indoors, there's not much you can do to stop nitrate leaching. Research and Development can't keep up. And although National's water policy promises $44 million to help clean up our waterways, the Government still has $450m set aside for irrigation subsidies that would only exacerbate the problem.
I accept dairy's importance to the New Zealand economy. But as of 2016, tourism is an even bigger export earner. And without careful policy and management, the two industries are at risk of finding themselves at odds.
And when you think about it, it's in both the tourism and agricultural sectors' long-term interests to protect our 100 per cent Pure brand.
Even the Minister for Primary Industries, Nathan Guy, foresees a point in the not-too-distant future where we reach maximum cow.
"One big opportunity the dairy industry does have is about increasing the value, not the volume," he said in April.
Value increases through effective branding. And as much of the world groans with the effects of overpopulation and climate change, a legitimate 100 per cent Pure brand will fetch even greater premiums for dairy products and tourism alike.
Charging for water used in commercial irrigation is one way of taxing dairy's inevitable pollution.
I know it'll cost.
I know it'll likely cost consumers.
But, as I explained to my American friends as we rolled past green fields and rows of irrigators, it's already costing us.