Exposure of mature green “Takanotsume” chili fruit to blue and red light-emitting diodes (LEDs) was investigated. The red LED accelerated the red color development of chili as indicated by higher a* and chroma values, as well as lower hue angle and total chlorophyll compared to the blue LED and darkness (control). These were linked to increases in β-carotene, free-capsanthin, and total carotenoids. The carotenoid biosynthesis-related genes, lycopene-β-cyclase (Lcyb), β-carotene hydroxylase (CrtZ), and capsanthin/capsolubin synthase (Ccs), were up-regulated by the red LED after 2 days of the experiment. The blue LED was more effective in increasing the expression of the phytoene synthase (Psy) gene at day 1 of experiment. The total phenolic, vitamin C content, and antioxidant capacity were also higher in the blue LED-treated chili. Results suggest that the responses of each carotenoid-related gene to the light wavelengths and the accumulation of phytochemicals are specific characteristics of this chili cultivar.

An intense red color appearance in hot chili is what industry commonly demands. The harvested mature green "Takanotsume" chili, a popular cultivar in Japan, incubated at 20 and 30 • C is investigated. At 30 • C, the chili rapidly degraded chlorophylls and obtained an intense red color, but presented an orange-red color at 20 • C. The sample showed higher carotenoid accumulations at 30 • C, along with significantly upregulated carotenoid biosynthesis-related genes-phytoene synthase (Psy), lycopene-β-cyclase (Lcyb), β-carotene hydroxylase (CrtZ), and capsanthin/capsorubin synthase (Ccs)-during the experiment. While the expression of the Ccs gene was reduced, there was a 5.5-fold upregulation of the Psy gene at the end of incubation. At 20 • C, the Psy gene was downregulated. These observations suggest that the expression of individual genes is temperature-dependent, and these would affect specific carotenoid compounds. The antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl; DPPH and ferric-reducing antioxidant power; FRAP) values had no difference between temperatures; the higher content of total phenolics and vitamin C presented in the chili at 30 • C probably corresponds to the advanced ripening process. Thus, 30 • C is the recommended incubation temperature for mature green chili to achieve the industry-demanded intense red color and high accumulation of phytochemicals.

␤ ␤ ␤ ␤ ␤-Lactoglobulin A solution at pH 6.4 was heated to 180 Њ Њ Њ Њ ЊC at the rate of 6 Њ Њ Њ Њ ЊC/min. By differential scanning calorimetry two independent endothermic peaks were observed. The first peak appeared below 100 Њ Њ Њ Њ ЊC is corresponded to the thermal denaturation of protein. This conformational change led to the aggregation and polymerization of molecules through disulfide linkage, particularly observed above 100 Њ Њ Њ Њ ЊC. The second endothermic peak appeared around 150 Њ Њ Њ Њ ЊC, which was brought by the decomposition of molecules as judged from electrophoresis. Up to 100 Њ Њ Њ Њ ЊC the viscosity of ␤ ␤ ␤ ␤ ␤-lactoglobulin A solution increased by heating, while the viscosity was reduced beyond 113 Њ Њ Њ Њ ЊC, due to change in the size of aggregate and decomposition of ␤ ␤ ␤ ␤ ␤-lactoglobulin A molecules.

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