Coca-Cola's newest product is being lauded as the "best tasting sugar-free Coke" but fans say they can still taste the difference.
Coke No Sugar is the company's third attempt at replicating the flavour of the drink without the cane sugar. In the original recipe sugar comes behind only carbonated water in terms of quantity in each can.
Diet Coke, Coke Zero and the new Coke No Sugar contain almost exactly the same ingredients in different quantities.
In Coke No Sugar the proportion of sweeteners in each drink is higher than the amount of flavour. In Coke Zero that is reversed. In Diet Coke the amount of flavour is greater than the amount of colour, food acids or sweeteners.
The only ingredient missing in Coke No Sugar, according to the label, is the preservative sodium benzoate.
Coca-Cola New Zealand country manager Sandhya Pillay said the new drink had been in development for more than five years and was the closest the company had yet come to replicating the classic taste.
"Coke Zero and Diet Coke have distinct taste profiles people love, but Coke No Sugar is different because it is a completely new recipe."
She said Coke No Sugar, which would be available in New Zealand from June 12, was actively encouraging no sugar.
"So this is us, this is Coca-Cola, actively saying here is a no-sugar drink, it tastes pretty much the same, it's your choice."
But in a blind taste test carried out by NZ Herald Focus, host Laura McGoldrick and ZM's Fletch and Vaughan all correctly picked which was the full sugar version and which was the new product.
The trio agreed the new drink did taste more like Coke than Coke Zero.
In the no-sugar drinks, Aspartame and Acesulphame potassium (Ace K) are used as sweeteners instead of sugar.
A Ministry for Primary Industries spokesperson said the sweeteners met New Zealand and Australia food safety requirements under the Australia New Zealand Food Standards Code so were safe for use.
They were permitted for use and had been assessed as safe internationally by the joint WHO/FAO Expert Committee on Food Additives, the spokesperson said.
Heart Foundation food and nutrition manager Dave Monro said water was always the best option in terms of health but if a no-sugar option switched people off a full-sugar version it was a step in the right direction.
Beverages were the highest contributor of sugar in the diets of Kiwi children, he said.
"While the association between high intakes of added sugar and tooth decay is well known, evidence now clearly shows that sugar affects body weight. There is also strengthening evidence for an impact of sugar on cholesterol, triglycerides, and type 2 diabetes which are all risk factors for heart disease."
He said the Heart Foundation would like to see companies reduce sugar levels in their standard products.
Anti-sugar lobby group FIZZ agreed it was a step in the right direction.
Founder of the group of doctors and health experts Dr Gerhard Sundborn said there remained concerns about such drinks - particularly with dentists - around their acidic content, which breaks down the enamel of teeth, and the caffeine they contained. However, sugar was certainly the worst offender.
New Zealand Medical Association chairwoman Dr Kate Baddock said the organisation acknowledged the effort Coca-Cola was making but it did not lessen the need for a tax on sugar-sweetened beverages.
What are Aspartame and Acesulphame potassium
Aspartame is more than 200 times sweeter than sugar and, according to the Ministry for Primary Industries website, the acceptable daily intake for it was 40mg per kilogram of body weight. That means a 70kg adult would have to drink 15-20 cans of diet soft drink a day to exceed it.
It is made up of two amino acids which are also found in foods which contain protein - aspartic acid and phenylalanine.
Some claim aspartame can cause cancer or other health problems but, according to the ministry, at least five robust studies have concluded that aspartame does not have this potential. Even at high doses, the metabolites of this sweetener did not accumulate in toxic amounts.
Acesulphame potassium was also 200 times sweeter than sugar and was not metabolised or stored in the body. Once eaten, it was quickly absorbed by the body and then rapidly excreted unchanged.
Coke ingredients in descending order by weight
Coke No Sugar: Carbonated water, colour (150d), food acids (338,331), sweeteners (951,950), flavour, caffeine.
Coke Zero: Carbonated purified water, colour (caramel 150d), food acids (338, 331), flavour, sweeteners (951, 950), preservative (211), caffeine.
Diet Coke: Carbonated purified water, flavour, colour (caramel 150d), food acids (338, 330), sweeteners (951, 950), preservative (211), caffeine.
Coke: Carbonated purified water, cane sugar, colour (caramel 150d), food acid (338), flavour, caffeine.