Shopping basket totals leapt up a few more pence this week as a result of an across-the-board hike in the per kg price of loose bananas from 64p at the top four to 85p.

Waitrose increased its price by 10p to 89p while 99p is the cost for a kg at Somerfield.

This week's report also reveals that Sainsbury and Somerfield have finally joined the other supermarkets in raising the price of a four-pint bottle of milk. This week's table shows that Sainsbury is now charging £1.11 for the white stuff while Somerfield has put its prices up by 15p, to £1.15.

The cost of this week's new shopping list at Sainsbury was £40.08 - just four pence more expensive than Morrisons, which managed to steal the third-cheapest supermarket spot this week after being narrowly beaten by its rival in last week's report.

Sainsbury was marginally more expensive than Morrisons for a number of branded ambient ingredients, although many of these were on some kind of special offer. Meanwhile, the cost of our shopping at Morrisons came to £40.04.

Asda and Tesco were once again the week's first and second-cheapest supermarkets. The cost of our 33 items at Asda came to £38.99, while the same basket of goods cost £39.55 at Tesco.

The top two were matching each other for price on 28 items this week - four fewer than in our previous report. While Tesco and Asda are carrying identical prices for all of their fresh produce items and household goods, our report shows that, like Sainsbury, Tesco is marginally more expensive for a selection of its branded ambient goods.

Waitrose's receipt rang in at £42.08, making it the week's fifth-cheapest supermarket.

Waitrose appears to have put the spotlight on price these past few weeks, as is further illustrated by the last month's data from The Grocer 100

At £44.01, Somerfield was this week's sixth-cheapest supermarket, predominantly due to a higher price for its own label beef steak mince.Grocery prices tumble

Grocery prices have tumbled by 1% in the period between the beginning of June and July. The cost of our secret 100-item basket of goods, which is compiled by retail research specialist ESA, has fallen by £1.60 over the past four weeks and is now at £175.21. This month's fall in prices can be attributed to the recent hot weather, which has fuelled an array of deep-cut promotions particularly on summer barbecue products at the top four supermarkets. This latest dip in prices follows the sharp increase that was seen in the period between May and June when prices had soared by 1.9% as a result of seasonality issues and changes in supply that affected the cost of some of the fruit and vegetable products on our shopping list. However, as the above chart clearly indicates, grocery prices still remain 1.5% higher than they were the same time last year.Over six months, Sainsbury soars the most

Basket prices at the top four supermarkets have increased over the past six months according to the latest results from The Grocer 100 pricing survey, which also reveals that Tesco is marginally cheaper than Asda, despite being 81p more expensive for the same basket of goods than it was in February. Asda's basket has risen by 2.7 % since February to rally by a further £2.78 in this last month, largely due to hikes in alcohol. Another retailer whose prices have risen by a considerable amount is Sainsbury - its basket price has grown by £4.41 in the past six months and currently costs £180.45. And while Morrisons is also 2.7% pricier than it was in February, our graph shows that it has been considerably cheaper than its rival since the end of May.Asda Almondvale Centre, Livingston

0 Our mystery shopper was able to collect a full 33-item basket of goods when she visited Asda's Almondvale store in Livingston.

She spotted two deals on items from The Grocer 33's list, including a two-for-£1 offer on Branston Pickle 360g and a two for £2.50 promotion on Kellogg's Variety packs.

We visited on 30 June 2006 at 12.40. Our shop lasted 60 minutes. Time spent at the checkout was 3 minutes.

tesco Resolution Road, Ashby de la Zouch

2 Our mystery shopper was only able to collect 30 items at Tesco Ashby de la Zouch. The store was out of stock of loose courgettes and Doritos corn chips. Our shopper was also told that McCain hash browns were not sold. She spotted six deals as she made her way around, five of which were 'two for one'-style offers.

We visited on 30 June 2006 at 14.00. Our shop lasted 54 minutes. Time spent at the checkout was 9 minutes 35 seconds.

sainsbury Allerdyce Drive, Drumchapel, Glasgow

0 First-class availability and customer service enabled Sainsbury's Drumchapel store in Glasgow to claim this week's Top Store Award. The store provided a full basket and our shopper was also able to take advantage of five deals on items from The Grocer 33's shopping list, including a buy-two-for-£3.50 offer on beef steak mince.

We visited on 30 June 2006 at 10.07. Our shop lasted 58 minutes. Time spent at the checkout was 3 minutes.

morrisons Station Road, Yate, Bristol

0 All 33 items were available at Morrisons' Yate store in Bristol. Our shopper said that she spotted a vast array of deals as she made her way around the store. There were offers on Robinsons whole orange, Colgate professional toothbrushes, Tetley tea bags and Morrisons' cheapest Australian red wine.

We visited on 30 June 2006 at 09.35. Our shop lasted 73 minutes. Time spent at the checkout was 7 minutes.

somerfield Queensway, Poynton

0 Our mystery shopper collected a full basket at Somerfield's Poynton store in Cheshire. He also spotted a staggering six deals on items from The Grocer 33's shopping list including white seedless grapes, celery, Danone Bio Activia, mince, Robinsons whole orange, own label mixed vegetables, and a Colgate Total Professional tootbrush.We visited on 30 June 2006 at 12.56. Our shop lasted 48 minutes. Time spent at the checkout was 8 minutes 20 seconds.

waitrose Penn Road, Beaconsfield

0 All 33 items on our shopper's list were available at Waitrose's Penn Road store in Beaconsfield, but only just, as she said that banana stocks were running quite low. She spotted no deals or special offers on any of the items from The Grocer 33 list.

We visited on 30 June 2006 at 10.38. Our shop lasted 40 minutes. Time spent at the checkout was 5 minutes.