Dry Romano beans (Phaseolus vulgaris) were soaked and cooked at temperatures ranging from 70 to 100$ sp circ$C for different time intervals. The rate of texture softening associated with each temperature was found to be consistent with two simultaneous pseudo first-order kinetic mechanisms 1 and 2. Approximately 40% of the firmness of Romano beans was lost by the rapid softening mechanism 1. The remaining firmness loss was characterized by mechanism 2 which was found to be much slower ($ sim$1/50th of the former). The temperature dependence indicator (z value) of reaction rate constants were 30 and 24 C$ sp circ$, respectively for mechanisms 1 and 2 with associated activation energies of 82 kJ/mole and 103 kJ/mole, respectively. / Turnip (Brassica napobbrassica) and beet roots (B. Vulgaris L.) were cooked at temperatures ranging from 70 to 100$ sp circ$C for different time intervals. Three textural properties (firmness, springiness, and stiffness) were found to follow the same trend of apparent first order kinetic theory with two substrates. Temperature dependence of softening (z value) was found to be within 27 and 35 C$ sp circ ,$ with activation energies in the range of 93 and 60 kJ/mole. / Cylindrical turnip, beet root pieces and Romano beans were packed in thin profile plastic containers and cylindrical metal cans and thermally processed in the static and rotational modes. Through heat penetration testing, process times were adjusted to give an equivalent lethality of 10 min for each product. Thin profile packed vegetables, in all cases, were found to have a firmer and stiffer texture. On the other hand, for rotational processing, the result showed no significant improvement in textural properties (firmness, springiness and stiffness) over the still counterparts. It was found that previously determined kinetic data could be used to estimate texture retention.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.23301 |
Date | January 1995 |
Creators | Taherian, Ali Reza |
Contributors | Ramaswamy, H. S. (advisor) |
Publisher | McGill University |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Format | application/pdf |
Coverage | Master of Science (Department of Food Science and Agricultural Chemistry.) |
Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
Relation | alephsysno: 001479857, proquestno: MM08055, Theses scanned by UMI/ProQuest. |
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