Hobnob or rich tea? Scientists reveal the best biscuits for DUNKING this International Biscuit Day – so do YOU agree with their choice?

Whether it’s a basic Malted Milk or a fancy Custard Cream, no good cup of tea is complete without a biscuit for dunking. 

With International Biscuit Day now here, one huge question remains – what is the best biscuit for dunking? 

Researchers from University Hospital of Wales set out to answer this important question, and completed a rigorous dunk test with four popular varieties. 

Their results revealed that the humble Hobnob is the best biscuit for dunking, closely followed by the Digestive. 

‘Biscuit dunking has a beneficial effect on tea cooling and should be encouraged, and the oat biscuit was the best at achieving this when compared with the digestive, rich tea, and shortie,’ the team wrote in their study. 

For the study, published in the BMJ, the researchers put four popular biscuits – Oat, Digestive, Shortie and Rich Tea – through their paces in the ultimate dunk test. 

While they recognise that chocolate-covered and cream-filled varieties are popular, they decided to exclude these from the study. 

‘We limited our biscuit choice, excluding chocolate and cream variants with their potential for high desirability as we believed it important to limit the distraction and potential finger licking that usually occurs when eating biscuits with cream or chocolate fillings,’ the team, led by Ceri Jones, wrote. 

Once the biscuits had been selected, a standard, ‘NHS-style’ brew was made for the test. 

To prepare this, the team poured 240ml of freshly boiled water over a single tea bag inside an unwarmed mug. 

This was stirred gently for 60 seconds, before the teabag was gently squeezed and extracted. 

Finally, 40ml of semi-skimmed cow’s milk was added, straight from the fridge. 

The most dunkable biscuit is an oat biscuit, which comes out ahead of a digestive biscuit, rich tea biscuit and a shortie

Once the perfect cuppa had been made, it was time to get dunking. 

The team assessed each biscuit across six factors – time to drinkable tea (TTDT), nutritional content, saturation volume, crunch reduction, dunk break point, and pragmatic dunk break point. 

Perhaps the most important test – the pragmatic break point test – saw the biscuits dunked in the tea for two seconds, before being held away from the cup to see how long they took to break. 

In this test, the Oat biscuit took the top prize, keeping in one piece for an impressive 29 seconds. 

The Shortie manage to hold on for 17.5 seconds, while the Digestive broke apart after just 8.5 seconds. 

Bringing up the rear was the Rich Tea, which only stayed together for a disappointing two seconds. 

Taking all six tests into account, the Oat biscuit was named the best for dunking.

‘The oat biscuit ranked first after all six tests,’ the team said. 

‘The digestive ranked second—it crumbled in three tests of absorptive capability and structural integrity (saturation volume, dunk break point, and pragmatic dunk break point). 

‘The shortie was ranked third, whereas the rich tea (the only biscuit given penalty points) was ranked fourth; the penalty points did not directly influence the rich tea’s ranking.’