The extraction of carotenoid pigments from shrimp heads left over from the processing of Litopenaeus vannamei has been shown to constitute an economically feasible alternative for aggregating value to shrimp processing waste. The objective of the present study was to extract, identify and quantify the main pigments found in shrimp heads collected at a shrimp processing plant in Ceará (Brazil). Samples were cooked for 15 minutes at 100 °C in water at a ratio of 1:2 until producing a mush. Carotenoids were extracted using cooled acetone and then hexane (the hexane phase). Subsequently, the DMSO phase was produced along with an acid fraction by partitioning with dimethyl sulfoxide. Following evaporation and drying, the carotenoids were identified in an open column using the elution parameter of the fractions, the visible absorption spectrum and the Rf value of the thin layer of silica gel. The absorption spectra of each fraction were read at 350-550 nm and quantified by thin-layer chromatography. The calculation of total carotenoids (37.62 µg.g-1 of the pigment mush) used the sum of the hexane, DMSO and acid fractions as well as the extinction coefficients of beta-carotene, astaxantin and astacin (2592, 2100 and 1690, respectively). The most abundant pigment was astaxantin (45.5%), followed by beta-carotene-5,6-epoxide (33.5%) and astacin (21.0%).
processing waste; shrimp; carotenoid pigments; astaxantin
