It's amazing what a bit of competition can do. No sooner had Aldi launched their new range of wines – and the news that they deliver for free – than Lidl and Morrisons released news of their plans in the sector. It's indicative of the growing importance of wine to supermarkets – last year the alcohol industry was worth £38bn ($48.9bn) to the UK economy. In 2015 £7.7bn was spent in Aldi, and 90 million bottles were sold in the supermarket. Aldi's Veuve Monsigny Champagne accounts for 1 in every 12 bottles of Champagne sold in the UK – serious numbers.

Aldi and Lidl clearly have their sights set on taking a large chunk of that cash. Two years ago both German giants were far better known for cheap cans of tomatoes and beans than wine. Frankly their selections were awful – cheap, but awful. Then Lidl launched its new wine selection, with classics like Champagne, St Emilion and pinots and chablis from Burgundy at very competitive prices – more than their previous £4 stuff, in the £7-12 range, but with much higher quality.

The results were almost instant. Lidl suddenly became a huge player in the supermarket wine world, challenging the "big four" – Sainsbury's, Tesco, Morrisons and Asda. All four have their variations of an 'own range' label too, which have proved very popular with customers.

With people reading online reviews and tweets these days a good review can make a huge difference. This year Asda's own-label La Moneda Reserva Malbec 2015 from Chile's Central Valley won the Best Red Single-Varietal Under £15 category at the Decanter Awards, scoring 95 points out of 100. Asda's website instantly crashed, and its shelves were emptied of the wine in just a day. It's still virtually impossible to find.

Aldi Reisling
Aldi's Exquisite Collection Clare Valley Reisling

So Aldi may be the last guest at the party, but they have entered carrying poppers and balloons. It's partly their range of wines – far classier than you might expect from a budget supermarket – but also the nuts and bolts of it. They are launching a new, free delivery service to anywhere in the UK. All you have to do is buy an initial six bottles on the web, that gets you an account and delivery date, and you can then buy as many or few as you want whenever you want.

This is particularly big news in London, where Aldi, unlike Lidl, has a minimum presence, especially in its centre. Lidl has opened some smaller 'metro'-type stores, but their wine selections are small because of physical limitations, and they don't deliver.

Lidl has fought back with its new French Wine Cellar collection, which features 42 wines from France's best-known regions, many of which have been sourced from vineyards just a short distance from some of the 'big names' in French wine. These include Chateau Roque le Mayne, Castillon Cotes de Bordeaux (£8.99), just 10 miles down the road from the famous Pomerol region; Les Ormes du Bosquet, Lussac-Saint-Emilion (£6.49), an example of a traditional Merlot from the Saint Emilion area; and Reuilly Domaine du Chene Vert, Loire 2015 (£8.99).

So are the Aldi wines actually any good? Their London tasting proved they were being taken seriously by the wine world – Amelia Singer, a familiar face from ITV's Wine Show, and Jane Anson from Decanter Magazine, were both in attendance and very impressed by the range.

Its Baden Pinot Blanc 2015 (£9.99) is floral and fresh, and very different to the usual fare. Even better is its 'Exquisite Collection' Muscadet 2015, which is rich, spicy and refreshing, and at £4.99 is a steal. If you prefer Aussies to French classics the Clare Valley Reisling (£6.99) is steely with a long finish, and their Marlborough Sauvignon Blanc (£7.49) is perfect for a pre-dinner refresher. The best value in the reds is the Argentinian Malbec Magnum, which is £11.99 for 1.5L – perfect if you're going to dinner with a lot of people.

Unusually all four dessert wines are very high quality, the best being the St Stephan's Crown Tokaji Aszu (£19.99).

Aldi may be late to the party – but they have entered with a bang.