High performance liquid chromatography (HPLC) evaluation of carotenoids in irradiated guavas

The use of ionizing gamma irradiation has shown very effective as an auxiliary technology for the decrease of post-harvest waste, grains disinfestation, pathogenic microorganisms control, increase in shelf life for meats, fruits, vegetables and bulbs and tubercles sprouts inhibition, maintaining nutritional quality. The carotenoids are pigments widely found in fruits and vegetables and are beneficial to human being health. This work was undergone using the irradiator with cesium source at the Army Technological Center, Brazil, with maximum dose rate of 2 kGy per hour. The objective is to evaluate the low gamma radiation doses (0.5, 1.0 and 1.5 kGy) influence in the total carotenoid and content lycopene in guavas CV Pal uma, with excellent weight classification. The total carotenoid content was extracted from the guava with acetone and moved to petroleum ether and determined by spectrophotometer at 450 nm. The determination of lycopene was accomplished by HPLC. The results showed that, in spite of lycopene loss with irradiation, the best dose was 0.5 kGy. (author)