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Influence of pulsed electric fields treatment on the extraction yield of betanine pigment from prickly pear (Opuntia Ficus Indica)Barbara Surano *, Nahuel Olaiz *, Fernando V. Molina +, Felipe Maglietti *, and Guillermo R. Marshall ** Laboratorio de Sistemas Complejos, DC, INFIP-CONICET, DF, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.+ Instituto de Química Física de Materiales, Ambiente y Energía (INQUIMAE), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.Opuntia cactus has become an important crop in arid and semi-arid regions, and it is widely used to prevent soil erosion and to combat desertification. Prickly pear fruit contains several pigments and bioactive compounds which provides added nutritional value. Consequently, interest in expanding its uses has risen, consuming the fruit not only fresh but also transformed into highly nutritive products of longer shelf life. One of the by-products from cactus pear fruit for the food industry are betalains, which are present in the pulp and the peel. The use of betalains obtained from Opuntia Ficus Indica as a natural food colorant is a very good alternative to artificial additives. Moreover, betalains have natural antioxidant activity that improves the nutritional quality of the product.The aim of this work was to study the influence of pulsed electric field (PEF) treatment on the extraction yield of betalains from prickly pear, and comparing the yield between different pulse trains.For this end three set of experiments were designed: a control group, and two PEF treatment groups in which a train of 5 and 25 pulses were delivered, respectively. The purple prickly pear discs were treated using a batch parallel stainless steel electrode chamber with a gap of 8mm. The samples were treated with a train of pulses of 100 μs at 1kV/cm and 10Hz and then centrifuged in a solution of sodium chloride 0,9%. The specific energy was 1,63 kJ/kg and 8,16kJ/kg for 5 and 25 pulses, respectively. The absorbance of the supernatants was measured and the concentration of betalains was calculated as mg betanine/gr fruit in 100ml. The results showed that the PEF treated samples had a higher extraction yield of betanine when compared to the control group. PEF treated samples had an increase of betanine concentration of 28,9% for 5 pulses and 54% for 25 pulses, compared to the control group. Therefore, the highest number of pulses led to the highest extraction. In conclusion, PEF treatment is an effective technology for the enhancement of the extraction of pigments from Opuntia Ficus Indica. However, further studies are needed to characterize the juice obtained, as well as its optimal processing and treatment conditions, to get a high nutritional ingredient for different food applications.Keywords:PEF, prickly pear, betanine, extraction