Impact of Combined Processes Involving Ultrasound and Pulsed Electric Fields on ENNs, and OTA Mitigation of an Orange Juice-Milk Based Beverage.

In recent years, several innovative food processing technologies such as ultrasound (USN) and pulsed electric fields (PEF) have emerged in the market, showing a great potential both alone and in combination for the preservation of fresh and processed products. Recently, these technologies have also shown promising applications to reduce mycotoxin levels in food products. Therefore, the objective of this study is to investigate the potential of the combined treatments USN + PEF and PEF + USN on the reduction of Ochratoxin A (OTA) and Enniatins (ENNs) of an orange juice mixed with milk beverage. For this purpose, the beverages were elaborated in the laboratory and individually spiked with mycotoxins at a concentration of 100 µg/L. They were then treated by PEF (30 kV, 500 kJ/Kg) and USN (20 kHz, 100 W, at a maximum power for 30 min). Finally, mycotoxins were extracted using dispersive liquid-liquid microextraction (DLLME), and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS-IT) was employed to determine them. The results showed promising applications, with reductions up to 50% for OTA and up to 47% for Enniatin B (ENNB) after the PEF + USN treatment combination. Lower reduction rates, up to 37%, were obtained with the USN + PEF combination. In conclusion, the combination of USN and PEF technologies could be a useful tool to reduce mycotoxins in fruit juices mixed with milk.

Scanning Electron Microscopy and Triple TOF-LC-MS-MS Analysis of Polyphenols from PEF-Treated Edible Mushrooms (L. edodes, A. brunnescens, and P. ostreatus).

Pulsed electric fields (PEF) technology has been used as a sustainable method for extracting antioxidant bioactive compounds from different food matrices. In the present study, the optimal conditions of PEF extraction for mushrooms (2.5 kV/cm, 50 kJ/kg, 6 h) were applied to Lentinula edodes, Agaricus brunnescens, and Pleurotus ostreatus to evaluate the total antioxidant capacity of the extracts, followed by the Triple TOF-LC-MS-MS analysis of the phenolic profile compared to A. bisporus by high-performance liquid chromatography coupled to mass spectrophotometry. In addition, the microporation effect of the technology on the mushroom surface was evaluated using scanning electron microscopy. A comparison was made with a maceration extraction (aqueous stirring for 6 h). The results showed that PEF-assisted extraction enhanced the recovery of antioxidant compounds such as 3,5-dicaffeoylquinic and cinnamic acid with contents up to 236.85 µg/100 g dry weight and 2043.26 µg/100 g dry weight from A. bisporus, respectively. However, mixed results were obtained for certain phenolic compounds, including vanillic acid from L. edodes, ellagic acid from P. ostreatus, and thymol from all mushrooms. These results indicate that the application of PEF technology is effective for the extraction of antioxidant compounds in fungal matrices by creating micropores in cell membranes that allow great recovery in matrices with high content of bioactive compounds.