Microbial destruction kinetics of high-pressure-processed sugarcane juice (Saccharum officinarum)

摘要

The efficacy of high-pressure processing (HPP) on inactivation of indigenous vegetative microorganisms in sugarcane juice was studied under the pressure range of 300-600 MPa for a treatment time of 1 s through 25 min at ambient temperature (30 +/- 2 degrees C). No significant change in pH, total soluble solids (TSS) and titratable acidity were observed in the juice, whereas color variation was significant (p .05) after HPP treatment. Application of HPP has significantly (p .05) reduced the vegetative microbial count with the increase in pressure and treatment time. Isobaric destruction of microorganisms followed first-order kinetics. Among the group of natural microflora studied, coliforms were observed to be more sensitive whereas aerobic mesophiles were least sensitive with the z(p) value of 846 MPa and the Delta V value of -6.85 x 10(-6) m(3)/mol. High-pressure treatment of sugarcane juice at 600 MPa/20 min was sufficient to inactivate vegetative microorganisms effectively with minimal changes in physico-chemical properties of the juice. Practical applications Sugarcane juice is one of the nutritious natural drinks available in South-Asian countries. The shelf-life of sugarcane juice is limited due to high incidences of microbial contamination, which begin immediately after extraction. Thermal processing of sugarcane juice at high temperatures and processing times has a detrimental effect on sensory and nutritional qualities of the juice. The application of high-pressure processing (HPP) has proved to be a promising technology to produce microbial safe sugarcane juice with minimal changes in physico-chemical properties. HPP technology can provide a breakthrough in the beverage industries, in developing a "ready-to-serve" sugarcane juice for the commercialization and marketability of good quality sugarcane juice.