Pulsed electric fields using a multiple needle chamber to improve bioactive compounds extraction from unprocessed Opuntia ficus-indica fruits

B. SURANO; F. MAGLIETTI; G. MARSHALL

JOURNAL OF FOOD ENGINEERING

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2022 vol. 1 p. 1 - 10

0260-8774

Prickly pear fruit is rich in natural pigments and bioactive compounds that contribute to its antioxidant capacityand health-promoting properties. These compounds can be extracted using pulsed electric fields (PEF), a nonthermaltechnology that is energy efficient and is being increasingly used for food processing. For that end, anovel electroporation chamber was designed and optimum pulse parameters were selected maximizing juiceyield and bioactive compounds extraction. The chamber consists of 5 rows of 10 parallel needles, and the optimumpulse parameters were: Sixty 100 μs long pulses of 1200 V/cm at a frequency of 10 Hz. The averageenergy input was 11.44 kJ/kg (temperature rise below 10 ◦C). When comparing PEF-treated samples with untreatedones, juice yield increased 3.3 times, and betalain extraction 1.48 times. Also, the juice extracted had asignificantly higher total polyphenol content (1.4 times), and antioxidant capacity (1.4–1.5 times increase,measured by three techniques). This chamber and procedure could be scaled for industrial applications sincelarge samples can be treated without the need of adding conductive medium or peeling the fruits, simplifying theprocedure and reducing costs. PEF treatment of prickly pear fruits can effectively provide juice rich in naturalcolorants and with higher nutritional properties.