HIGH-PRESSURE INACTIVATION OF SACCHAROMYCES-CEREVISIAE, ENDOGENOUS MICROFLORA AND PECTINMETHYLESTERASE IN ORANGE JUICE

Authors
Citation
Me. Parish, HIGH-PRESSURE INACTIVATION OF SACCHAROMYCES-CEREVISIAE, ENDOGENOUS MICROFLORA AND PECTINMETHYLESTERASE IN ORANGE JUICE, Journal of food safety, 18(1), 1998, pp. 57-65
Citations number
20
Categorie Soggetti
Food Science & Tenology","Biothechnology & Applied Migrobiology
Journal title
ISSN journal
01496085
Volume
18
Issue
1
Year of publication
1998
Pages
57 - 65
Database
ISI
SICI code
0149-6085(1998)18:1<57:HIOSEM>2.0.ZU;2-Q
Abstract
Decimal reduction times (D-values) for Saccharomyces cerevisiae ascosp ores inoculated into pasteurized orange juice ranged from 4 to 76 s at pressures between 500 and 350 MPa. At the same pressures, D-values of S. cerevisiae vegetative cells ranged from 1 to 38 s while those for the native microflora in nonpasteurized Hamlin orange juice were betwe en 3 and 74 s. Corresponding z-values were 123, 106 and 103 MPa for as cospores, vegetative cells and native microflora, respectively. Native microorganisms that survived high pressure treatments included yeasts , gram-positive and gram-negative bacilli Pectinmethylesterase activit y in nonpasteurized Hamlin orange juice was reduced to 5% of initial a ctivity after 30 s at 900 MPa.