A study was conducted to determine alpha-and beta-carotene and beta-cryptoxanthin in twenty-two fruits and vegetables. Foods were obtained from wholesale distributors from five locations throughout the United States (Los Angeles, Dallas, Chicago, Miami, and Boston) three times during a year (November, March, and July). Mean vitamin A activity in retinol equivalents (RE) of each food along with average values for the individual carotenoids (pg/lOOg) are given. beta-Carotene was the most prevalent carotenoid. Carrots, beet greens, spinach, Swiss chard and sweet potatoes had the most vitamin A activity. Analysis of variance indicated that there were no significant differences among either locations or time of analysis. A comparison was made between the new values and the ones listed in . There were differences between the old and new values in 14 of the 22 fruits and vegetables analyzed.

A high-performance liquid chromatographic method has been developed to quantify a-and @-carotene in some raw fruits and vegetables. Fresh products were extracted with stabilized tetrahydrofuran and concentrated by rotary evaporation. Samples were injected onto a Vydac 218TP54 reversed-phase column with a mobile phase of 40:56:4 acetonitrile/methanol/tetrahydrofuran. Detection was at 470 nm with a sensitivity of 0.04 AUFS. There were no interferences from the cis isomers of @-carotene, but one of the several isomers of a-carotene will interfere with @-carotene. Other carotenoids such as @-cryptoxanthin, canthaxanthin, y-carotene, 5,6-epoxy-5,6-dihydroxy-@,@-carotene, and the 9 and 15 cis isomers of @-carotene can be separated with this system. The method has been shown to be very reproducible with coefficients of variation ranging from 2.79 to 7.26%. Results from the carotene analyses of nine fruits and vegetables from three different supermarkets are given.

Chia seed, Salvia polystachya, was analyzed as a source of oil, polysaccharide, and protein for possible use by the food industry. Seeds were found to contain 30% oil of which more than 90% was composed of triglycerides. The fatty acid composition of the oil was found to consist mostly of C16:0, ClS:O, C18:2 and C18:3. The protein content of chia seed was found to be 23.4%. A very viscous polysaccharide was isolated from the seeds. Acid hydrolysis followed by gas liquid chromatographic analysis demonstrated that xylose and arabinose were the major constituents of the polysaccharide. Seeds were found to contain niacin, riboflavin, and thiamin at a concentration of 83, 2 and 14 pg/g seed, respectively. Spectrochemical analysis showed the presence of eleven elements with calcium, potassium, and phosphorus being the most prominent. The percentage of unsaturated fatty acids, the concentration of protein and the viscosity of the polysaccharide in chia seeds would indicate that further research should be conducted to investigate possible food uses for these seeds.

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