Estimation of silica in cane juice using near infrared spectroscopy

aamarpali ratna puri, Guru Nanak Dev University, Amritsar
S Kaur, Guru Nanak Dev University, Amritsar

Abstract

The ICUMSA or AOAC (Association of Official Agricultural Chemists) traditional test methods for testing individual constituents, pol and brix are time consuming, operator dependent and involve the use of hazardous chemicals. The increased awareness for environmental and health topics makes desirable to avoid the clarification of cane juice with basic lead acetate. Widely used in the food and agricultural industries, Near Infrared Spectroscopy NIR has now made considerable inroads into the more lengthy and wet chemistry procedures. Near Infrared is the region of combination bands and overtones due to interatomic forces. Hydrogenic atoms being the lightest vibrate within the near infrared region due to N-H, O-H and C-H groups. These are common atoms present within the most food products. As near infrared wavelengths are specific, individual components can be identified so it can be used for quantitative analysis of impurities in cane juice. During sugar crystallization silica creates problems by forming calcium silicate scales in the inner surface of boilers, which are too hard to be removed. Near Infrared Spectrophotometer of Elico (India) range (600-2500nm) has been used in it’s transmittance mode in conjunction with two multivariate calibration procedures i.e Partial Least Square Regression analysis (PLSR) and Stepwise Multivariate Linear Regression analysis (SMLR) for the analysis of silica in cane juice. The PLSR procedure proved to be more accurate. Multi linear regression analysis was also carried out and the wavelengths identified were 943 and 1912nm with standard deviation of 35.29.