If you're striving to get energised during the brisk January mornings or need a boost to conquer the mid-afternoon lull, Dunkin' Donuts may just have the solution.

They've introduced StrongBrew, a robust vanilla iced coffee touted as "crafted to meet the needs of health-conscious and fitness-focused customers".

This latest iced beverage is sugar-free vanilla syrup with skimmed milk and 20g of protein for those keeping an eye on their food this January.

Our reviewers sampled Dunkin's newest concoction and believe it stands shoulder to shoulder with rivals Costa and Starbucks, reports the Mirror.

Lottie Gibbons said: "I was pleasantly surprised by Dunkin's new StrongBrew. As someone who has always enjoyed iced coffee, especially the vanilla flavour, I tend to be mindful of the sugar content in flavoured syrups.

"When I tried Dunkin's StrongBrew, I was amazed to discover that the vanilla flavouring is completely sugar-free. Despite this, it didn't taste artificial and was perfectly sweet, satisfying my sweet tooth without feeling overly indulgent.

"I was initially sceptical about the 20g of protein in the drink. In my experience, protein powders in cold beverages can sometimes leave a chalky texture if not blended properly.

"However, Dunkin's StrongBrew was impressively smooth, with no trace of grittiness.

"Overall, I was thoroughly impressed by StrongBrew. It's a game-changer, and I wouldn't hesitate to choose it over similar offerings from Starbucks or Costa Coffee."

Rebecca Koncienzcy said: "I am not always an iced coffee fan, but this is smooth and strong. Make that very strong. It has a very rich flavour and no bitter aftertaste.

"And did I mention it is strong? With one sip it was like having a coffee shot, I am not sure I am going to be able to sleep tonight despite drinking the Dunkin's StrongBrew at lunchtime. This caffeine punch is for hardcore coffee fans or people who really need a pick-me-up.

"The only problem now is when you buy one, resisting the urge to pick up a delicious doughnut, too."

On the other hand, Kate McMullin said: "I found the iced coffee very strong, which for some may be ideal but for me it was a little too overpowering, especially in such a large drink.

"I think it is a good alternative to a high-calorie iced coffee, but I think you would have to be a coffee lover to be able to stomach the rich and quite bitter taste."

Those eager to try the StrongBrew can get their first drink free at one of Dunkin's 28 stores by downloading the Dunkin' app. Existing users, who gained early access to the StrongBrew on January 1, will receive double points for purchasing the drink through the app during the promotion.

According to Christopher Rodaway, head of marketing at Dunkin' said: "We all know that after the festive period we start focusing on our gym goals and our protein intake rockets."

"Dunkin' has announced the release of a new protein coffee drink which is designed to support fitness and wellness goals.

"We wanted to create something that not only tastes great but also supports those goals.

StrongBrew is packed with protein and tastes delicious, meaning it's the perfect accompaniment for anyone looking to hit their protein intake."

Dunkin's is launching additional new items to their range in January, including two fan-favourite vegan-friendly doughnuts returning to stores.

The Chocolate Rainbow and Vanilla Rainbow are joined by seven other options, available to those following Veganuary.