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The effect of high-intensity pulsed electric fields (HIPEF) or thermal processes and refrigerated storage on water-soluble vitamins and antioxidant capacity of beverages containing fruit juices and whole (FJ-WM) or skim milk (FJ-SM) was assessed. Peroxidase (POD) and lipoxygenase (LOX) inactivation as well as color changes were also studied. High vitamin C retention was observed in HIPEF and thermally treated beverages, but a significant depletion of the vitamin during storage occurred, which was correlated with antioxidant capacity. HIPEF treatment did not affect the concentration of group B vitamins, which also remained constant over time, but thermally treated beverages showed lower riboflavin (vitamin B2) concentration. With regard to enzyme activity, thermal processing was more effective than HIPEF on POD and LOX inactivation. The color of the beverages was maintained after HIPEF processing and during storage. Consequently, HIPEF processing could be a feasible technology to attain beverages with fruit juices and milk with high vitamin content and antioxidant potential.

Effects of high intensity pulsed electric fields (HIPEF) or thermal treatments over carotenoids of mixed beverages were evaluated after processing and during refrigerated storage. Nine carotenoids were identified in all samples, being β‐carotene the major compound. Just after processing, concentration of most individual carotenoids diminished around 6–30% in fruit juice‐skim milk (FJ‐SM) and fruit juice‐whole milk (FJ‐WM) beverages; except, 9‐cis‐violaxanthin‐neoxanthin, antheraxanthin and phytoene‐phytofluene which increased in the thermally treated FJ‐SM (5–19%) and 9‐cis‐violaxanthin‐neoxanthin which also augmented in HIPEF processed FJ‐SM (24%). Total carotenoid (TC) content decreased (6–13%) in both beverages, irrespectively of the treatment applied. Through the storage, individual carotenoid concentration varied widely in all beverages, depending on the carotenoid structure; however, TC tended to decrease. Nonetheless, changes observed HIPEF‐treated beverages were less than those in the conventionally pasteurized ones. Hence, HIPEF is as effective treatment, or even more, than heat processing to preserve bioactive compounds in mixed beverages. Practical Applications Nowadays, modern population is claiming for products with high antioxidant properties and attractive flavor. In this sense, mixed beverages formulated with fruit juices and milk are attracting the attention of consumers due to their exotic taste and their elevated concentration of bioactive substances, such as carotenoids. However, these compounds are very susceptible to heat and are easily degraded during processing and storage. Hence, finding preservation technologies for mixed beverages capable to maintain their carotenoid concentration as high as possible after treatment and during shelf‐life is one of the greatest challenges for the food industry. In this sense, the relevance of this study is to demonstrate that high intensity pulsed electric fields processing is a potential alternative to thermal pasteurization in order to obtain not only safe but nutritious fruit juice‐mixed beverages with elevated concentration of carotenoids, especially those with pro‐vitamin A activity, such as β‐carotene.

The influence of High Intensity Pulsed Electric Fields (HIPEF) or Thermal Treatment (TT) on minerals and fatty acids of fruit juice-whole (FJ-WM) or skimmed milk (FJ-SM) beverages was assessed after processing and during chilled storage. Mineral profile of both beverages was characterized by Ca, Zn, Fe, Mg, Cu, and Mn; being Ca the macroelement detected at the highest concentration (3.06-3.17mg/100mL). Neither HIPEF nor TT significantly affected mineral concentration of the beverages, except Fe, which augmented after HIPEF (300%) or TT (43%). During storage (56 days), mineral content in both bevearges remained highly stable, regardless of the treatment applied. 11 fatty acids were identified in untreated and processed FJ-WM beverages. Palmitic acid was detected at highest concentration (21.83-24.37mg/100g of fat). Immediately after HIPEF or TT, most fatty acids remained with no significant changes, only linoleic acid increased (20%) in HIPEF treated beverage. Fatty acid content of HIPEF treated FJ-WM beverages was kept constant along storage; only palmitic, linoleic and linolenic acids showed lower concentrations (12-20%) at day 56. Conversely, the concentration of most fatty acids in the heated beverage underwent a significant reduction (7-19%) with time, except palmitic acid, which remained constant. HIPEF can be considered as a potential alternative to conventional pasteurization to obtain stable mixed beverages with significant concentrations of health-related compounds.