USE OF FILTRATION AND BUFFERS IN RAW SUGAR COLOR MEASUREMENTS

Colour, an important parameter in quality evaluation of raw sugar solu tions, is sensitive to and greatly affected by pH and turbidity of the solutions. Buffers and filtration were used to control the problemati c colour fluctuations due to the above factors. The buffers used to ma intain pH included glutaric acid, citric acid, 3-(N-morpholino)-2-hydr oxy-propane sulphonic acid (MOPSO), triethanolamine (TEA) and tris-hyd roxymethy-aminomethane (Tris). The turbidity was minimised by using gl ass-fibre filters with a 0.7-mu m Fore size in series. The results sho wed that by using MOPSO buffer and three glass-fibre filters in series , the effect of pH and turbidity on colour measurement of raw sugar so lutions can be minimised. MOPSO buffer combined excellent pH stabilisa tion at pH 7.00 and limited colour alteration.