The presen investigation deals with the deterioration of the dry seasoned noodle ―a kind of the convenient foods―under the various environmental conditions during the long period of storage.
Some chemical properties of the noodle fats and the digestion coefficients of the noodle proteins were determined to observe the degree of the deterioration. The follow ing results were obtained.
It was recognized, in general, that acid values, peroxide values and T. B. A. values increased during the storage, and that iodine values, on the contrary, decreased. These tendencies depended upon the environmental conditions under which it is kept in storage ; that is, it seemed that the both factors of sunlight and temperature influenced the rancidification of fats, and the chemical properties changed in proportion as the fats acidify. Among the chemical properties of fats, T. B. A. value was the most suitable index in order to observe the fats rancidity.
The polymerization of the fatty acids was affected by sunlight and temperature, and remarkably by the former, showing the same results as in the case of the other chemical properties ; that is, the formation of dimers or trimers of the fatty acids was recognized most clearly in the cae of sunshine-exposure.
The rises of the digestion coefficients of the proteins were recognized, more or less, in all groups, but here again the rise in the sunshine exposed group showed the greatest change.
In vies of the above facts, the most reasonable conclusion to be drawn from the available data is that, in order to prevent the deterioration of D. S. N., it is the most suitable method to preserve it in the dark place at a temperature as low as possible.