Influence of pulsed electric fields treatment on the extraction yield of betanine pigment from prickly pear (Opuntia Ficus Indica)

MAGLIETTI, FELIPE; OLAIZ, NAHUEL; SURANO, BARBARA; MARSHALL, GUILLERMO

Norfolk

Congreso; 2nd World Congress on Electroporation and Pulsed Electric Fields in Biology, Medicine, and Food & Environmental Technologies; 2017

p { margin-bottom: 0.1in; direction: ltr; line-height: 120%; text-align: left; }p.western { }p.cjk { }Opuntia cactus has become an important crop in arid and semi-aridregions, and it is widely used to prevent soil erosion and to combatdesertification. Prickly pear fruit contains several pigments andbioactive compounds which provides added nutritional value.Consequently, interest in expanding its uses has risen, consuming thefruit not only fresh but also transformed into highly nutritiveproducts of longer shelf life. One of the by-products from cactuspear fruit for the food industry are betalains, which are present inthe pulp and the peel. The use of betalains obtained from OpuntiaFicus Indica as a natural food colorant is a very good alternative toartificial additives. Moreover, betalains have natural antioxidantactivity that improves the nutritional quality of the product.The aim of this work was to study the influence of pulsed electricfield (PEF) treatment on the extraction yield of betalains fromprickly pear, and comparing the yield between different pulse trains.For this end three set of experiments were designed: a controlgroup, and two PEF treatment groups in which a train of 5 and 25pulses were delivered, respectively. The purple prickly pear discswere treated using a batch parallel stainless steel electrode chamberwith a gap of 8mm. The samples were treated with a train of pulses of100 μs at 1kV/cm and 10Hz and thencentrifuged in a solution of sodium chloride 0,9%. The specificenergy was 1,63 kJ/kg and 8,16kJ/kg for 5 and 25 pulses,respectively. The absorbance of the supernatants was measured and theconcentration of betalains was calculated as mg betanine/gr fruit in100ml. The results showed that the PEF treated samples had a higherextraction yield of betanine when compared to the control group. PEFtreated 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 highestextraction. In conclusion, PEF treatment is an effective technologyfor the enhancement of the extraction of pigments from Opuntia FicusIndica. However, further studies are needed to characterize the juiceobtained, as well as its optimal processing and treatment conditions,to get a high nutritional ingredient for different food applications.