Robinsons Soft Drinks Ltd

Dear Sirs.I have over recent years drunk Robinsons sugar free squash. My wife purchased two one and a half Ltrs bottles from our local Tesco store.On trying the drink it left an almost powder like taste. So we tried the second one and it was the same.I found this a most unpleasant taste.Could it be that you have changed the sweetener. Tesco have refunded the cost but i would rather it found its way back to you for testing.RegardsP.Hirst.