The effect of temperature, U. V. irradiation were carried out in the anthocyanin pigments (ANs) extracted from purple yam (UBE) and papilionaceae (PA) stored in air and nitrogen. The results obtained were as follows.
1) After storage for 23 days, the colorant remaining ratio of UBE and PA ANs solution heated to 30°C was 97 and 77 % while that of the same heated to 60t was 61 and 30%. When heated to 90°C, UBE and PA ANs showed the lowest colorant remaining ratio.
2) After storage heated to 60°C for 23 days, the colorant remaining ratio of UBE and PA ANs stored in ampule (air) were 62 and 30 %. But both ANs stored in ampule (nitrogen) was more stable at 85 %.
3) UBE and PA ANs solution was irradiated direct with a sterilizing lamp for 6 hr. As a result, the colorant remaining ratio of both AN were 20-30 %. But UBE and PA ANs in ampule showed the highest colorant remaining ratio of 95 and 100 %. However, both AN stored in outdoor decomposed for 4 days.
4) Several kinds of additive were added to UBE and PA ANs solution, and the obtained solution was heated. As a result, both AN decomposed paticularly with L-ascorbic acid and hydrogen peroxide.