Thanks are due to Mr. Preston Stogsdill and Ms. Cheryl Jensen of the EM core facility, MU for technical assistance. This investigation was part of the work for the M.S. thesis of coauthor Siddhartha S. Roy. This work was supported in part by a grant from the United States Department of Agriculture National Research Initiative (96-35500-3321).
Textural and Ultrastructural Changes in Carrot Tissue as Affected by Blanching and Freezing
Article first published online: 20 JUL 2006
Journal of Food Science
Volume 66, Issue 1, pages 176–180, January 2001
How to Cite
Roy, S.S., Taylor, T.A. and Kramer, H.L. (2001), Textural and Ultrastructural Changes in Carrot Tissue as Affected by Blanching and Freezing. Journal of Food Science, 66: 176–180. doi: 10.1111/j.1365-2621.2001.tb15602.x
- Issue published online: 20 JUL 2006
- Article first published online: 20 JUL 2006
- MS 19990326
- freezing rate;
- transmission electron microscopy
ABSTRACT: The impact of blanching and freezing conditions on firmness retention and ultrastructural changes in the cell wall and middle lamella of carrot tissues were studied. Freezing caused extensive degradation of cell wall pectins as evident from the rapid loss in tissue firmness. High-temperature short-time blanching (100°C, 0.58 min.; 90°C, 2.12 min.) retained firmer texture than low temperature long time blanching (80°C, 11.64 min.; 70°C, 71.1 min.). Freezing at rapid rates of -4.5°C/min and -2.4°C/min showed less softening than slow rates of -0.19°C/min and -0.05°C/min. Softening was further enhanced in blanched-frozen carrots. Severe structural damage due to growing ice crystals and substantial loss of pectic material were seen at slower freezing rates.