Exploiting Pulsed Flows for Heating Improvement: Application to Determination of Total Reducing Sugars in Molasses and Sugar Cane Juices

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Evandro R. Alves (Author) Other; Mário A. Feres (Author) Other; Elias A.G. Zagatto (Author) Other; José L.F.C. Lima (Author) FFUP

Journal

Title: Current Analytical Chemistry

Vol. 5 No. 1

Pages: 65-69

ISSN: 1573-4110

Publisher: Bentham Science

Indexing

ISI Web of Knowledge - 7 Citations

ISI Web of Science

Scopus - 7 Citations

Scientific classification

FOS: Medical and Health sciences > Other medical sciences

CORDIS: Health sciences

Other information

Authenticus ID: P-003-PK7

Resumo (PT): Laminar and pulsed flows typical of multi-commuted and multi-pumping flow systems, were evaluated in relation to analytical procedures carried out at high temperatures. As application, the spectrophotometric determination of total reducing sugars (TRS, hydrolyzed sucrose plus reducing sugars) in sugar-cane juice and molasses was selected. The method involves in-line hydrolysis of sucrose and alkaline degradation of the reducing sugars at about 98 °C. Better results were obtained with pulsed flows, due to the efficient radial mass transport inherent to the multi-pumping flow system. The proposed system presents favorable characteristics of ruggedness, analytical precision (r.s.d. < 0.013 for typical samples), stability (no measurable baseline drift during 4-h working periods), linearity of the analytical curve (r > 0.992, n = 5, 0.05 - 0.50% w/v TRS) and sampling rate (65 h-1). Results are in agreement with ion chromatography. <br> <br>

Abstract (EN): Laminar and pulsed flows typical of multi-commuted and multi-pumping flow systems, were evaluated in relation to analytical procedures carried out at high temperatures. As application, the spectrophotometric determination of total reducing sugars (TRS, hydrolyzed sucrose plus reducing sugars) in sugar-cane juice and molasses was selected. The method involves in-line hydrolysis of sucrose and alkaline degradation of the reducing sugars at about 98 °C. Better results were obtained with pulsed flows, due to the efficient radial mass transport inherent to the multi-pumping flow system. The proposed system presents favorable characteristics of ruggedness, analytical precision (r.s.d. < 0.013 for typical samples), stability (no measurable baseline drift during 4-h working periods), linearity of the analytical curve (r > 0.992, n = 5, 0.05 - 0.50% w/v TRS) and sampling rate (65 h-1). Results are in agreement with ion chromatography. <br> <br>

Language: Portuguese

Type (Professor's evaluation): Scientific