Fevertree Drinks, a supplier of premium carbonated mixers for alcoholic spirits, has performed strongly during its first six months ended 30 June 2015.In a trading update on Wednesday, the company said it expects first-half sales to be at £24m, up 61% from same time last year.June was a particularly strong sales month for Fevertree, driven by customers and importers building inventory ahead of the summer season. As a result, the group forecasts full-year results to be materially ahead of board expectations.Investec analysts maintained their 'buy' recommendation and raised their price target from 240p to 320p, amid "very strong period of growth".However, Shore Capital retained their 'sell' recommendation as the broker plans to discuss with management what the underlying sales rate for the year is before upgrading its current estimates.Shares in the company jumped 8.71% to 315.25p on Wednesday at 1508 BST.