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Clarification of the type VHP sugar syrup by hydrogen peroxide: chemical implications, technological and microbiological

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Author(s):
Juliana Lorenz Mandro
Total Authors: 1
Document type: Master's Dissertation
Press: Piracicaba.
Institution: Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC)
Defense date:
Examining board members:
Claudio Lima de Aguiar; Luciana Francisco Fleuri; Marcos Yassuo Kamogawa
Advisor: Claudio Lima de Aguiar
Abstract

Nowadays, the sugar-energy industry is becoming increasingly competitive, which indeed is encouraged mainly by representative demand and requirements of foreign markets. When analyzing the production of refined sugar can be found barriers to their widespread international acceptance due to the clarification method employed, since this is performed by burning elemental sulfur in combustion boilers. The use of sulfite above the permitted limits can result in potential public health problems. In this regard, Brazil has conducted studies on the adoption of new technologies to replace the sulfite, without changing the quality of the produced refined sugar. On that basis, it was done the evaluation of the use of hydrogen peroxide (H2O2) in commercial solution (35% v/v) as an alternative reagent to sulfur dioxide to obtain refined sugar with less ICUMSA color. For this the sugar liquor VHP different doses of hydrogen peroxide were tested, together with different pH and temperatures outside a central composite design, enabling optimization and monitoring of changes resulting from the process. Thus there was obtained as the best pH conditions 7.5 to 10, temperatures between 50 and 70 °C and dosages between 500 and 797.6 ppm H2O2. The analysis from the chemical kinetics of the peroxidation of the liquor has observed greater reductions in ICUMSA color in general in the time of 50 minutes to 75 minutes and in the first 25 minutes to the extremes of pH, temperature and H2O2 dose. As for sucrose degradation was not a significant factor, since it in most cases was first degraded within 5 minutes and after this time remained without many changes, being more vulnerable conditions (3.32 and 11.68), high temperatures (83.6 °C) and H2O2 maximum dosage (1000 ppm) applied. In addition to further reduce color ICUMSA H2O2 Liquor also showed such a good antimicrobial agent, particularly when combined with high temperatures. Acting with more intensity in the decrease of bacteria than the reduction of fungi. The artificial neural network (ANN) showed good fit and indicated the variable ° Brix (soluble solids) as the one with the greatest influence in reducing the ICUMSA color and variable time that less influenced the color reduction. (AU)