How very refreshing: Tank beer is so fresh it's like drinking straight from the brewery

Now one company is offering these unpasteurised pints in selected pubs. Will Coldwell tries a draft with a difference.

As soon as you enter The Grove pub in Balham, south London, you see them. Two copper cylinders at the far end of the bar. Resting next to one another like oversized boilers, their polished exteriors shimmer with a rose-tinted reflection of the pub's interior. But the industrial beauties are not just there for show. This is tank beer, a way of serving beer that preserves its freshness so well that it claims to be as good as if you're drinking it in the brewery itself. Rolled out in three Young's pubs in south London by the Greenwich-based brewer Meantime, it is another innovation of the unstoppable craft-beer revolution.

No one is more proud of this fact than Meantime's CEO, Nick Miller. Seated in the pub wearing a striped suit with a pin badge emblazoned with the company's name, I find him drinking a coffee. Still, this doesn't stop him thrusting a pint of "brewery fresh" London Lager in front of me to try. As I sip on my pint, wary of the fact that it's barely midday, he explains why the company decided to invest in tank beer.

"You need theatre, you need to communicate to people what makes a beer and why it tastes the way it does," he says.

"The social history of beer is enormous in this country – Britain was the brewing capital of the world bar none. I think you can always learn from all corners of the world and I think we as an industry have been guilty of not innovating enough. Hopefully Meantime can make a small change to this."

Tank pubs are already common in Europe, especially in countries such as the Netherlands and the Czech Republic, where they are known as tankovna. In the UK, however, the method of serving is only found in pubs that have micro-breweries attached. Now they look set to become more widespread. Meantime has already lined up 10 more pubs to have the tanks fitted and in testament to the concept, other, bigger, brewers are preparing to follow suit.

One of the reasons tank beer tastes so fresh is that, unlike all the other lagers you'll find pouring out of the taps at your local, it's unpasteurised, unfiltered and is maturing right up to the moment it hits your pint glass. Pasteurisation is the process used to remove any bacteria and live yeast from beer and is done by flash-boiling it. While it gets rid of any bugs that could damage the flavour, the process itself is slightly staling, taking away some of the subtlety of taste and aroma from the beer. As Miller says: "Why would you go and mature a beer for 40 days and then flash boil it?"

But by ensuring no bacteria gets in its beer in the first place, then transporting the beer directly from the brewery to the specially engineered tanks in the pub using vacuum-sealed bags kept at a constant temperature, Meantime is able serve its lager unpasteurised, without having to worry about any loss of flavour. The technical process means the beer has no contact with the air until it hits your pint glass.

For Alastair Hook, founder and Brewmaster of Meantime, brewery fresh is a dream come true. "When you make a product that you're proud of, the journey to the customer is when it all starts to go wrong," he says. "I liken it to charging a battery. When you're at the brewery the battery is fully charged and the beer is exactly as you'd want it. It has all the nuances of tastes and flavour that you want. Bringing customers into the brewery and taking them to the maturation tanks, where the beer is gently, slowly, improving itself is the kind of nirvana. That's how every brewer would want to serve and sell their beer. But you can't bring thousands of people into your brewery. If I had my way, in five years' time Meantime would only be selling beer in brewery-fresh tanks."

And it does taste better. Don't expect your taste buds to explode – it is subtle – but compared to its London Lager served in the usual manner, the beer has a fuller body, a softer mouth feel and a warmer flavour. There is a creamier head to it and the delicate fruity flavours are easier to pick up on.

But really, the improved freshness of the beer is just an aspect of this endeavour, which is tied up with the way drinkers are engaging with beer more than ever. The fact that Meantime opted for a lager, rather than a more exotic variety of beer to launch its tanks with, shows it is shooting for casual drinkers, luring them into the world of craft beer.

It's certainly worked at The Grove. "It sells itself," the bar manager, Mike Lane, says. "It's been the No 1 drink for the last two weeks. You don't even really have time to start explaining about it being unpasteurised or anything like that… they just say I'll have another one of those!"

How to know if your beer is fresh

By Sophie Atherton

I think anyone who drinks beer should be able to tell straight away if it's not fresh, but they may not be bold enough to say anything about it.

Despite the popular mythology that British beer is warm and flat, it shouldn't be. It should be quite lively. C02 is a natural by-product of the brewing process so all beer should have some carbonation in it, whether it's tank beer or served from a cask. Because every beer tastes different, the freshness is to do with how it feels in your mouth almost as much as the flavour.

When you drink beer it should feel refreshing and have a liveliness that you might experience as a tingle on the tongue, with gentle and refreshing bubbles rather than fizziness. A beer should taste like that and if it doesn't, it should have a jolly good reason not to.

It's hard to describe it because it's a very subjective thing, but just compare it to food. If someone serves you up a plate of food and it was made with less than fresh ingredients you know pretty quickly. If the vegetables are old, or the salad leaves are going brown, you can taste it. It's the same with beer. If you're coming to the end of the cask the beer can taste a bit tired. It just doesn't quench your thirst, it doesn't feel as lip-smackingly wonderful as it does when it's really fresh.

But we do need to be bolder as consumers. If something doesn't taste quite right take it back to the bar and politely but firmly tell them so. You catch more bees with honey than you do with vinegar. And don't listen to that nonsense which is, "well, no one else has complained". That's only because we're not very good at complaining. A good pub will offer you something else and if there's something wrong with the beer they'll take it off.

Sophie Atherton was the first woman in the UK to become an accredited beer sommelier. She writes about beer and has just launched a new podcast The Beer Talkers, thebeertalkers.com