ASSESSMENT OF THE EFFECT OF DIFFERENT EMERGING TECHNOLOGIES ON THE EXTRACTION OF BIOACTIVE COMPOUNDS FROM BLUEBERRY (Vaccinium myrtillus)

Blueberry (Vaccinium myrtillus) is an exotic fruit, renowned for its health-promoting properties and nutritional benefits and can be consumed either fresh or processed. It is particularly notable for its high levels of anthocyanins and some phenolic acids, which are bioactive compounds associated with antioxidant, anti-inflammatory, and cardioprotective properties. Recent researches have applied emerging technologies to optimize and improve the extraction of these health-promoting compounds. In this context, this study aimed to evaluate the effect of emerging technologies on the extraction of bioactive compounds of freeze-dried blueberry ethanolic extract. The freeze-dried blueberry samples were diluted in 80% ethanol and subjected to the following extractions, pulsed electric field (P.E.F.) 6kV or 8kV for 1 min., 1:10 (m/v) ratio; ohmic heating (O.H.) 75kV or 175kV (frequency 60kHz, 30 and 70 V·cm⁻¹ of electric field, respectively) for 10 min., 1:10 (m/v) ratio; cold plasma (C.P.) 10kV or 13kV (frequency 5kHz) for 10 min., 1:20 (m/v) ratio. The extracts were analyzed on colorimetric parameters, total phenolics and total anthocyanins. The colorimetric parameters showed a variation regarding the extraction technology applied, for P.E.F. L* (23.07±0.01/ 23.30±0.02), a* (1.03±0.03/ 1.06±0.02), b* (-0.79±0.04/ -0.69±0.11) 6kV and 8kV, respectively; O.H. L* (23.26±0.01/ 23.84±0.23) a* (0.74±0.09 /1.06±0.06) b* (-0.71±0.09/ -0.56±0.0) 75kV and 175kV, respectively; and C.P. L* (23.59±0.03 / 24.65±0.01) a* (2.70±0.02/ 2.71±0.04) b* (-0.27±0.08/ -0.19±0.04) 10kV and 13kV, respectively, the most different parameters are found using C.P.  In other hand, the quantification of total anthocyanins for PEF (5.91±0.12/ 6.18±0.13) 6kV and 8kV, respectively; for O.H. (5.52±0.14/ 8.75±0.16) 75kV and 175kV, respectively; and for C.P. (4.59±0.05/ 5.0±0.16) 10kV and 13kV, respectively (expressed as mg of malvidin-3-glucoside ∙ L^-1 of extract) and the total phenolic compounds in P.E.F (913.96±72.61/ 1057.26±46.66), respectively; for OH (971.06±30.48/ 1555.01±10.77) 75kV and 175kV, respectively; and for C.P. (774.26±42.88/ 917.91±94.45) 10kV and 13kV, respectively (expressed as mg of GAE ∙ L^-1 of extract) follow the same pattern. Even though the colorimetric parameters are similar, the total anthocyanins and total phenolics show higher differences, inferring that the best extracting method applied was O.H. at 175kV. The ohmic heating demonstrated higher efficiency for extracting bioactive compounds from blueberry compared to other emergent technologies.