Shore Capital has reiterated its 'hold' stance on sugar and sweeteners group Tate & Lyle following a 'constrained' third-quarter trading update in which it scaled back its profit guidance for the full year.The company said that, despite a solid start to the final quarter, constant-currency profits for the year ending March 31st are now expected to be broadly in line with last year on the back of lower Splenda sucralose pricing. The company had said that half-year stage that it had expected "another year of profitable growth".Shore Capital's Darren Shirley said that he will provisionally downgrade his full-year profit estimate by 3% to £327m, equating to earnings per share of 56.8p, more or less unchanged from £329m and 57p reported for the year ended March 2013, respectively."Looking into FY2015, we also place our forecasts under review for a downgrade revision, noting the increased pressure on Sucralose pricing and margins from what is believed to be 'a significant overhang of unsold Chinese sucralose' which is expected to drive prices down c.15% year-on-year."Shirley said that flat third-quarter volumes in the Speciality Food Ingredients (SFI) division were "disappointing" after 5% growth in the first half. Meanwhile, the performance of the Bulk Ingredients (BI) division was held back by lower co-product returns.He said that Tate & Lyle invested in its SFI infrastructure in recent years to improve visibility and build control over it profits stream. "However, today's statements confirms to us that despite such investment, large elements of the BI and (it appears) sucralose profit streams remain out of the companies control, whilst volume momentum from SFI still remains modest," he said.Shirley said that the stock is trading at around 14 times earnings on his revised 2014 forecasts.The stock was down nearly 15% at 668.79p by 11:12 on Thursday.BC