Endogenous levels of tocopherols and ascorbic acid were quantified by high-performance liquid chromatography (HPLC) during fruit ripening of New Mexican-type chile peppers (Capsicum annuum L.). γ-Tocopherol (γ-toc) was present in seeds, while R-tocopherol (R-toc) was present in the pericarp. γ-Tocopherol content reached its maximum concentration in seeds from red, succulent fruit and then declined. R-Tocopherol increased from the green to dry red maturity stages. Cultivars differed for R-toc but not for γ-toc contents. Ascorbic acid content increased after the green mature stage and peaked in red fruit with about 75% moisture content. Ascorbic acid was highest in the cultivars NuMex R Naky and Sandia.

The β-carotene and total carotenoid content of either fresh or dried tissue of fruits of a total of 57 cultivars of six Capsicum species were analyzed using high performance liquid chromatography (HPLC). β-Carotene levels in ripe fruit varied from 0 to 166 μg·g-1 fresh weight, and carotenoid levels were from 1 to 896 μg·g-1 in ripe fruit in 1996. The range of values for β-carotene was similar in 1997, but that for total carotenoids was wider (4 to 1173 μg·g-1 fresh weight). Fresh fruit of the cultivars Greenleaf Tabasco, Pulla, Guajillo, NuMex Conquistador, Ring-O-Fire, and Thai Dragon contained greater amounts of β-carotene per 100 g fresh weight than the recommended dietary allowance (RDA) for vitamin A for the average adult. For dried Capsicum entries, New Mexican, aji, pasilla, and ancho types had the highest levels of β-carotene. In 1996, β-carotene levels among the dried Capsicum germplasm ranged from 2 to 739 μg·g-1 dry weight, and carotenoid levels from 111 to 6226 μg·g-1. Values were higher in 1997, ranging from 24 to 1198 μg·g-1 dry weight for β-carotene and from 187 to 10,121 μg·g-1 for total carotenoids. A pasilla type (C. annuum L.) had the highest total carotenoid content among the dried entries in both years.

Oxidative carotenoid degradation causes paprika color loss during storage. Ethoxyquin, a synthetic antioxidant, is used in the spice industry to prevent carotenoid loss during postharvest handling. However, ethoxyquin treated paprika is unacceptable for some markets and consumers. Naturally derived antioxidants, i.e., rosemary extracts, ascorbic acid, ␦-tocopherol, and mixed tocopherols were tested as color protectants in two paprika cultivars. Extractable color, surface color and carotenoid concentrations were determined before storage and then monthly. After 4 mo storage at ambient temperature, the control treatment lost 63% of the initial extractable color, the ␦-tocopherol treated samples lost 32%, and the ethoxyquin lost 6% color.

The β-carotene and total carotenoid content of different Capsicum fruit types and species were analyzed using HPLC. This information is useful for breeding high carotenoid chiles (New Mexican type) for the food industry, and also provides nutritional data for the range of fruit types within the Capsicum genus. Fresh fruit from 25 accessions and dried fruit from 39 accessions were evaluated in 1996 and 1997. β-carotene levels varied from 0 to 16.6 mg/100 g fresh weight, and carotenoid levels were from 0.1 to 89.6 mg/100 g in red ripe fruit in 1996. The range of values for β-carotene was similar in 1997, but a wider range in total carotenoids (0.4 to 117.3 mg/100 g fresh weight) was observed. Fresh fruit (100 g) of the cultivars `Greenleaf Tabasco', `Pulla', `Guajillo', `NuMex Conquistador', `Ring-O-Fire', and `Thai Dragon' contained greater amounts of β-carotene than the RDA for vitamin A for the average adult. For dried Capsicum entries, New Mexican, aji, pasilla, ancho, and guajillo types had the highest levels of β-carotene. In 1996, β-carotene levels among the dried Capsicum germplasm ranged from 0 to 739.2 μg/g dry weight, and carotenoid levels were from 21.3 to 6,225.9 μg/g. Values were higher in 1997, and ranged from 23.7 to 1,198.1 μg/g dry weight for β-carotene and from 76.9 to 10,120.6 μg/g for total carotenoids. A pasilla type (C. annuum) had the highest total carotenoid content among the dried entries in both years.