Please use this identifier to cite or link to this item:
|Type:||Artigo de periódico|
|Title:||Thermal design process for acidified canned papaya (Carica papaya L.) pulp|
|Abstract:||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.|
|Editor:||Food Nutrition Press Inc|
|Appears in Collections:||Unicamp - Artigos e Outros Documentos|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.