It wasn't that long ago that vegans were seen as a bit 'earthy' and unconventional. Times have already moved on since then, though.
Veganism might not be mainstream yet, but it is very much in vogue. It's difficult to measure but, in the US, it's estimated that 6% of consumers now 'identify' as vegan, a figure that is more than replicated in many markets in Western Europe and in Australasia.
Drill down to just Millennial females, and that percentage becomes even more significant. What's more, these numbers do not incorporate the 'part-time vegans', seduced to the lifestyle by its newly-found fashionable status.
One drinks-related development of this trend is the strong growth in recent years of milk alternatives, which explains why Danone paid an eye-watering amount last year - US$12.5bn - for plant-based food supplier WhiteWave. Clearly, Danone had been studying the charts.
Soft drinks operators will inevitably be asking themselves what they can do to appeal to this burgeoning audience. No doubt, as I write, NPD teams will be hard at work on innovation to exploit this irresistible trend.
If I was developing a product specifically for the vegan market, my starting point would be to ensure the product is fortified with the B12 vitamin: Deficiency in B12 is the Achilles heel of the vegan diet. I would add in some iron too because that's another issue for vegan purists.
The instinct would be to go for a short-life, smoothie-style product, but that would limit export opportunities and you don't want the product sitting on the shelves of Wholefoods going off.
With one eye on the café, coffee shop and restaurant market, I would opt for a clear carbonated product. The female bias of veganism, meanwhile, would shape the flavour choice of the range - drinks with a blueberry, cranberry, elderflower or pomegranate twist tick plenty of boxes. Maybe even a non-alcoholic rosé?
The packaging, of course, will need to be squeaky-clean green and the drink would have to be organic.
Promoting the drink should be relatively straightforward: The vegan community is very active on social media - if they like it, they will soon tell each other. It would also be wise to hand pick one of the many celebrities who have gone vegan to endorse the drink. How about Ariande Grande? Get PETA to let you put their name on the label and an association with an animal charity should do the trick.
Achieve all this, and I'm certain you'll find customers who are desperate to stock your product. After all, supermarkets are now establishing vegan aisles and they're seeking out products to put in them. On-premise outlets are also anxious to embrace this rising segment of the market.
The biggest problem I can foresee is that 'ethical' doesn't come cheap. Meanwhile, vegans may be well-educated, but they are often young and cash-poor. This means that price is a deterrent, making specific vegan soft drink products still very niche.
Only the big operators have the scale to deliver this sort of product to market at anywhere near the right price. The problem is that 'large' and 'corporate' is not a great fit with the vegan culture. Indeed, a supplier of a vegan soft drink might be expected to have the characteristics of a craft-style producer.
What larger companies can do is ensure that their products comply with the 'rules' and in reality, most soft drinks do meet the requirements. Some orange and apple CSDs do contain gelatine (extracted from animal by-products) which is not compliant. There are also some red-coloured products that use cochineal, a colouring sourced from a type of insect - Back in 2012, Starbuck's Pink Drinks was flagged up by a vegan blog for using cochineal, leading to the company switching to a tomato dye alternative.
Drinks with caffeine in them are not ideal because it drains calcium out of the system. That's no good for those with a non-dairy diet.
Then, it may not be the product itself that fails the vegan test; the production process may fall foul of the strict criteria. Some concentrate juices, for instance, may be distilled through non-vegetarian ingredients and will not qualify for a vegan label.
Soft drinks companies must be diligent because the vegan community is understandably very vigilant and their dietary intake is subject to intense scrutiny and is discussed extensively online. You don't want to be caught out, even if you've acted with the best of intentions.
And, you can never be complacent. In the UK last year, Diet Pepsi came under the microscope, resulting in PepsiCo having to reveal that it used a non-vegan ingredient in the drink. The reluctance to reveal what the ingredient was prompted unfavourable coverage among vegans. That's not good PR.
The soft drinks industry can learn a lot from Diageo, which is increasingly proactive in acknowledging the vegan market. Almost a year ago, the group responded to vegan concerns over the use of isinglass - the air bladder of a fish - in the filtration process of Guinness by finding an alternative. The company has even unveiled a vegan version of Baileys. Subsequently, the use of alternative ingredients and techniques has opened up Diageo's products to an even wider consumer base.
Going forward, veganism is set to maintain its impressive momentum. Soft drinks player need to tread carefully to make sure that they get on - and stay on - the vegan list.