Artículos de revistas
Thermal design process for acidified canned papaya (Carica papaya L.) pulp
Registro en:
Journal Of Food Process Engineering. Food Nutrition Press Inc, v. 22, n. 2, n. 103, n. 112, 1999.
0145-8876
WOS:000081618600002
10.1111/j.1745-4530.1999.tb00474.x
Autor
Magalhaes, MMD
Tosello, RM
Massaguer, PR
Institución
Resumen
Previous results showed that the heat resistant portion of pectinesterase in the acidified papaya pulp var. "formosa" presented greater thermal resistance than Cl. pasteurianum. Based on this, and determined F-77C(7.8C), a value of 12.3 min was calculated using the heat resistant portion of pectinesterase as the target for the process, and applying 1.7 decimal reduction of the activity of the heat resistant enzyme (98% inactivation). Using Shiga (1976) an empirical relationship and a heating time of 12.9 min in water bath at 97C was established for the process. Three processing tests were carried out under these conditions using 6 cans per test. The processing values varied from 12.33 to 12.75 min at 77C. Statistical analysis showed no significant difference between tests and among cans as well as test at the 0.05 and 0.01 a level. After processing the cans, gelatinization, activity of remaining enzyme and micro-organism growth were not detected. This shows that the process was able to inactivate the heat resistant portion of pectinesterase and kill the natural micro-flora present on the pulp. By considering the initial variation of the pectinesterase activity in the pulp and F-77C(7.8C) - value of 16.7 min, a safety factor for the process was applied. This process was equivalent to 15 min of heating in water bath at 97C and corresponded to 2.3 decimal reductions in activity of heat resistant pectinesterase. An inoculation pack study was performed to verify the microbiological safety of such process. Each can of papaya pulp was inoculated with I mt of a 10(4) spore/mL suspension of Cl. pasteurianum. Swelling of the cans, growth after subculturing and pectinesterase were not detected after incubation, showing that the pulp could be safely processed. The storage test showed no significant changes in the color, flavor, aroma and texture of the canned acidified papaya pulp. 22 2 103 112