Shares in Sainsbury's fell back after the supermarket reported a slowdown in sales growth between the first and second quarters and predicted slower growth to come.Excluding the impact of the fuel and the VAT cut announced last November, like-for-like sales were up by 5.4% from the same period the previous year in the quarter, the second of the company's financial year.The rise in sales compares favourably with the 2.1% rise in sales rival Tesco announced yesterday, but is lower than the 7.8% growth Sainsbury's recorded in the first quarter.Sainsbury's chief executive Justin King said he expects market growth to slow in coming months due to reduced inflation.However, he said sales of the store's non-food ranges were growing at nearly three times the rate of food, with its clothing range now an established part of its offering.Total sales were up by 6.8% excluding fuel, he said. During the quarter it opened 12 convenience stores, bringing the total for this financial year to 19, and 19 supermarkets, including 14 Somerfield and Co-operative supermarkets that were acquired earlier in the year.Sainsbury's is on track to grow space by 15% in the two years to March 2011, King said.'Our performance in the first half continues to show good progress as we also invest for the future,' he said.'While we expect market growth to slow in the coming months due to reduced inflation, the universal appeal of our focus on quality and value leaves us well positioned going forward.'