Influence of pulsed electric fields processing on the bioaccessible and non-bioaccessible fractions of apple phenolic compounds

Pulsed electric fields (PEF) are known to influence the chemical and microstructural factors governing apple phenolic compounds fate upon digestion. However, the effect of PEF on fruit phenolic compounds bioaccessibility has yet to be determined. This work assessed the effects of PEF treatment (0 and 24 h after 0.01, 1.8 and 7.3 kJ kg−1) on the bioaccessible and non-bioaccessible fractions of apple phenolic compounds. Bioaccessible and non-bioaccessible 5-caffeoylquinic acid increased at 24 h after delivering 0.01 kJ kg−1 (61 and 35%, respectively). At 1.8 and 7.3 kJ kg−1, the overall bioaccessible content decreased, although the percentage of compounds released (bioaccessibility) increased in some cases. Bioaccessibility of overall phenolic compounds increased from 14% (untreated) to 27% (24 h after 7.3 kJ kg−1). Therefore, PEF processing could modulate the apple functional value, by either increasing phenolic contents in the bioaccessible and non-bioaccessible fractions or the phenolic bioaccessibility.This work was supported by the Spanish Ministry of Economy and Competitiveness (grant AGL2013-44851-R). Albert Ribas-Agustí is holder of a post-doctoral grantJuan de la Cierva-formación from the Spanish Ministry of Economy and Competitiveness

Applying pulsed electric fields to whole carrots enhances the bioaccessibility of carotenoid and phenolic compounds in derived products

We propose the application of pulsed electric fields (PEF) to carrots to obtain derived products with increased phenolic and carotenoid bioaccessibility. For this purpose, juices, purees, and oil-added purees were obtained from whole PEF-treated carrots (five pulses of 3.5 kV cm−1 ; 0.61 kJ kg−1 ). In order to obtain shelf-stable products, the effect of a thermal treatment (70 ◦C for 10 min) was also studied. Carrot juices exhibited the highest carotenoid (43.4 mg/100 g fresh weight) and phenolic (322 mg kg−1 dry weight) contents. However, caffeic and coumaric acid derivatives were highly sensitive to PEF. The phenolic bioaccessibility reached 100% in purees obtained from the PEF-treated carrots, whereas the further thermally treated oil-added purees exhibited the greatest carotenoid bioaccessibility (7.8%). The increase in carotenoid bioaccessibility could be related to their better release and solubilization into micelles. The results suggest that food matrix aspects apart from particle size (e.g., pectin characteristics) are involved in phenolic bioaccessibilityThis research was funded by the Ministerio de Economía y Competitividad (Spain) grant number AGL2013-44851-R and Ministerio de Ciencia, Innovación y Universidades (Spain) grant number RTI2018-095560-B-I00. López-Gámez, G. thanks the Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) for the predoctoral grant (2019FI_B2 00129