I presume you are referring to this:
ballyvolanespirits.ie/our-spirits/
Lots of nice marketing.
"Using whey alcohol from the local dairy farmers here in Cork, together with our own natural well water and an interesting mix of locally foraged and grown botanicals, we have hand-crafted a gin that highlights the character of Bertha in her prime."
The reality:
www.eveningecho.ie/corknews/Holy-cow-Its-gold-medal-for-Cork-gin-3434c245-4812-44c3-b733-bbc17dc1f484-ds
"Produced by close friends Justin Green and Anthony Jackson, who have known each other since they were 13 years-old, the gin is distilled using whey alcohol that comes from a dairy farm in Carbery."
www.liquidirish.com/2012/05/whey-alcohol.html
"It was an Irish company that first figured out how to make potable alcohol commercially from whey: Carbery, in Cork. Carbery is a dairy ingredients company which, in the 1970s, happened to be owned by Grand Metropolitan.
...
As far as I can make out, fermentation is preceded by ultrafiltration to remove the whey proteins (a useful product in its own right) and reverse osmosis to eliminate much of the water. By this means, the concentration of lactose is increased. After fermentation, a wash of about 3.5% ethanol is obtained which is then distilled to 96% ABV, the maximum achievable in a column still.
That's going a little further than allowed under whiskey rules, where the maximum is 94.8%, in order to ensure some flavour from the original grain remains. I'm not sure, then, whether there is any trace of whey flavour left at this point. Doubtless for some applications the closer to neutral alcohol the better. But I'll revisit this point in another article.
The venture was entirely successful and the "Carbery process" was subsequently licensed to plants in the US and New Zealand.
...
Whatever was the case in the distant past, we are certainly turning whey into spirits in huge quantities today. Carbery is pumping out close to 10m litres of ethanol per year. Some of that is for quaffing, some is further refined to 99.9% ABV and added to Maxol petrol.
"
So it's, er, petrol! It's fucking petrol and they market the hell out of it that it's some sort of premium product. As far as I can see, whey alcohol has NEVER been regarded as a premium product.
I mean I'm sure it's probably fine, it's just shows that it is literally just industrial alcohol with flavourings, and not some mystical product from Daisy the cow.