Du är här

Analysis of temperature distribution in potato tissue during blanching and its effect on the absolute residual pectin methylesterase activity

Författare:
Publiceringsår: 2004
Språk: Engelska
Sidor: 433-441
Publikation/Tidskrift/Serie: Journal of Food Engineering
Volym: 65
Nummer: 3
Dokumenttyp: Artikel
Förlag: Elsevier

Sammanfattning

Dynamic changes in absolute residual PME activity in potato tubers undergoing blanching were analysed with regard to the temperature distribution in the tissue after the treatment. The finite-element technique was used to predict the temperature distribution within the tissue during blanching. The temperature-related behaviour of the enzyme indicated that blanching between 60 and 70 degreesC induced thermal activation of PME in blanched potatoes. The temperature distribution in the tissue during blanching showed that activation takes place as soon as the tissue reaches an average temperature above 50 degreesC. However, the temperature dependence of the absolute residual PME activity in the tissue, when blanching at temperatures between 50 and 70 degreesC, did not follow Arrehenius' law. The degree of PME activity in the blanched tissue was found to depend on the "effective exposure time" to the temperature at which the activation/deactivation of the enzyme takes places. Thermal activation of PME in potato tissue occurred during the first two minutes of blanching. Longer heating times induced rapid deactivation of the enzyme in the tissue. (C) 2004 Elsevier Ltd. All rights reserved.

Disputation

Nyckelord

  • Chemistry
  • Finite-element analysis
  • Thermal deactivation rate
  • Absolute PME activity
  • Thermal activation
  • Temperature distribution
  • Potato
  • Blanching
  • Thermal activity coefficient

Övriga

Published
Yes
  • ISSN: 0260-8774

Box 117, 221 00 LUND
Telefon 046-222 00 00 (växel)
Telefax 046-222 47 20
lu [at] lu [dot] se

 

Fakturaadress: Box 188, 221 00 LUND
Organisationsnummer: 202100-3211
Om webbplatsen