The mathematics model and analysis for the influence of Zinc ion density on vegetable resuming-green effect

摘要

Chlorophyll is very instability, is easy to fade very much during the course of vegetable processing and storing, which can affect badly the quality of green vegetable product. The complexes can be formed adopting zinc ion to carry through color preservation processing, which can hold or resume its original green color, it is the most ideal method protecting color for vegetable now. The results measured by computer color quantitative system show: the chromaticity a* of zinc-adding sample presents the phenomenon which first increase, and then reduce gradually along with the increase of heating time. Namely, the experiment samples appear a course from fading to resuming green, and that the higher zinc ion density, the better the resuming-green effect of vegetable is. The samples adding 750ppm zinc ion appear color dynamic change course from green→yellow brown→green. The samples beyond range of 1500ppm zinc ion don't raise the intermediate link that changes yellow brown, and the depth of green isn't same along with the increase of heating time. The a* value of control sample increases gradually along with the increase of heating time; this explains that green is faded gradually and has been become yellow brown. The a* value has a reduction in the range of 5 minutes, this is because gas in cell organization is heated and evolved, those chlorophyll which haven't been damage is emerged, green deepens, vegetable color becomes bright and shine. The mathematics model which chromaticity a* is variational along with the zinc ion density and heating time is gotten through the method of orthogonal polynomial regression design, the confidence level is 99%, fitting result is good, which offers certain theory foundation for the following production.