Composition in fatty acids of the pericarp and seeds of two new pepper fruits (Capsicum annuum L. cv. Jaranda and Jariza) and the effects of different processing stages on the fatty acid composition of these tissues and of paprika are shown. In the pericarp the polyunsaturated fatty acids (PUFA), linoleic and linolenic, both in the same proportion, are the major acids; in the seed, linoleic is in a very high concentration as compared to in the pericarp. In the pericarp, a storage zone of carotenoid pigments, linolenic acid does not participate in the carotenoid esterification process. From the different lipid patterns, nutritional aspects are deduced. In the drying step the concentrations of constituent fatty acids are constant in the seed, while in the pericarp there is a net increase in the total content of fatty acids.Paper no. J8983 in JAOCS 76, 205-208 (February 1999).In plant tissues, the most abundant saturated fatty acids are palmitic and stearic, and the most common unsaturated fatty acids are oleic, linoleic, and linolenic (1). These fatty acids are synthesized in aerobic sequential desaturation, from stearic (18:0) to oleic, then to linoleic, and finally, to linolenic (2). Such reactions can take place in both the plastid and the endoplasmic reticulum (3,4) by the action of the desaturase enzymes. However, due to the different substrate specificity of the plastid acyltransferases, the glycerolipids synthesized in the plastids have an sn-1 C 18 and sn-2 C 16 distribution, while those synthesized outside the plastids have a C 16 or C 18 combination at position sn-1 but only C 18 at sn-2.In the ripe fruit of the pepper (Capsicum annuum L.), the major lipids are mono-and diacylgalactolipids, while in the endoplasmic reticulum, the major lipid is phosphatidylcholine (5). Fatty acids are accumulated in both the pericarp and the seeds (6,7). Those found in the pericarp, besides fulfilling their structural function as basic components of the cell membrane, are important for the proper incorporation of other membrane compounds. During ripening of the pepper, besides a series of structural changes, disappearance of chloroplasts, and formation of chromoplasts (8), new pigments are biosynthesized that are exclusively carotenoid, esterified to a greater or lesser degree (9,10). The fatty acids esterified to the xanthophylls are mainly lauric, myristic, palmitic, oleic, and linoleic, forming mono-or diesters (11). The pigments are thus more liposoluble and at the same time more stable to photo-and thermoxidative reactions and other processes involving the enzyme lipoxygenase. This greater stability results in longer conservation of the color (a quality used to evaluate both the fruit and its commercial derivatives paprika and oleoresin).To obtain paprika, the pepper must be dehydrated by heating and then ground. The dehydration stage is not the end of the metabolic life of the fruits, since, as has been demonstrated in previous works (12,13), pigments may continue to be synthesized or transformed into others, alteri...

Consumers demand traditional, tasty tomatoes in contrast to new hybrid cultivars that have poor sensory characteristics. Some physicochemical parameters (total soluble solids, pH, titratable acidity, color and firmness), functional properties (vitamin C, lycopene, β-carotene and total antioxidant activity) and sensory characteristics of five traditional tomato varieties (T1-T5) in three ripening stages, grown under organic conditions, were evaluated. These were compared to the commercial hybrid ‘Baghera’, grown in the same conditions. Firmness of all varieties declined and the color parameters L* and H* decreased, whereas a* and a*/b* increased progressively with ripening. Lycopene also increased with ripening in all varieties, with the highest content being 132.64 mg kg−1 fw for T4. All traditional tomato varieties were richer in lycopene than commercial ones in the two last ripening stages. Vitamin C content ranged widely between 27.33 and 267.27 mg kg−1 fw. Among the traditional varieties, T2 (BGV003524) stood out due to its highest total soluble solids and vitamin C contents, total antioxidant activity, and H* and a*/b*; this variety was also the most appreciated by panelists. These traditional varieties could be an alternative to commercial cultivars, as they have good quality characteristics and can satisfy consumer demand for organic produce.

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