Abstract

In this study, we survey about the effect of pretreatment on the sultana (Raisin) color. We use from three kinds of solutions, 0, 5 and 10% of potassium carbonate salt and 5 % of Pakistan oil for pre treating. Dried grapes are stored at three levels of temperature (4°, 18° and 32°C) with three relative humidity. Relative humidity gets from saturated solution of potassium carbonate salt, potassium acetate and sodium chloride salt. We assess the color of samples in (2, 5 and 8 months) by Hanterlab. Color analysis indicates that the factors are studied (chemical pretreatment, temperature, keeping time) affect on color of raisins indexes. During keeping time the lowest index L pertains to those samples which are kept at 4°C and by increasing keeping temperature index L decreases and index a/b increases. A/b index will decrease when the concentration of potassium carbonate in emulsion increase and therefore color will be brighter.

Keywords:

Chemical pretreatment, color, storage conditions, raisin,

References

Competing interests

The authors have no competing interests.

Open Access Policy

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Copyright

The authors have no competing interests.