New approaches for the effective valorization of papaya seeds: Extraction of proteins, phenolic compounds, carbohydrates, and isothiocyanates assisted by pulsed electric energy

Abstract The study compares the efficiency of common aqueous extraction (CE) at different pH (2.5–11) and temperatures (20–60 °C) and extraction assisted by pulsed electric energy (pulsed electric fields, PEF or high voltage electrical discharges, HVED) of nutritionally valuable and antioxidant compounds from papaya seeds. The exponential decay pulses with initial electric field strengths of ≈ 13.3 kV/cm and ≈ 40 kV/cm for PEF and HVED treatments, respectively, were used. The number of pulses n was changed within 1–2000. The impacts of temperature and pH on extraction efficiency of different components (proteins, total phenolic compounds, carbohydrates, isothiocyanates) and antioxidant capa…

Current and future strategies to reduce salt consumption

Abstract The development of healthier lifestyles is of great importance in modern societies. Due to the increasingly sedentarism of population, our current diets need to be adapted to reduce the consumption of salt, fats, and sugar to prevent chronic diseases such as obesity, diabetes, cardiovascular, and respiratory diseases, among others. For example, salt consumption is increasing considerably worldwide, which has been accompanied by the increased rates of heart disease incidence, mainly in developed countries. The food industry is making considerable efforts to provide lower salt food with similar taste, texture, and shelf-life as conventional food to promote not only healthier consumpt…

Ultrasound-assisted green solvent extraction of high-added value compounds from microalgae Nannochloropsis spp.

Abstract The aim of this work was to investigate ultrasound (US)-assisted green solvent extraction of valuable compounds from the microalgae Nannochloropsis spp. Individual green solvents (water, ethanol (EtOH), dimethyl sulfoxide (DMSO)) and binary mixture of solvents (water-DMSO and water-EtOH) were used for the extraction procedures. Maximum total phenolic compounds yield ( Y p  ≈ 0.33) was obtained after US pre-treatment ( W  = 400 W, 15 min), being almost 5-folds higher compared to that found for the untreated samples and aqueous extraction ( Y p  ≈ 0.06). The highest yield of total chlorophylls ( Y c  ≈ 0.043) was obtained after US ( W  = 400 W, 7.5 min), being more than 9-folds highe…

Pulsed electric field and pH assisted selective extraction of intracellular components from microalgae Nannochloropsis

Abstract The study was aimed at investigation of the potential of pulsed electric field (PEF) pre-treatment as a preliminary step of pH-assisted aqueous extraction of algae components from microalgae Nannochloropsis suspensions. The PEF and sonication (S) were compared as pretreatment methods. They were applied at normal (pH = 8.5) and basic (pH = 11) conditions, and supplementary basic extraction (at pH = 11) was done. The extracts were analyzed for content of pigments, proteins, carbohydrates, total phenolic compounds and antioxidant capacity. The colloidal stability of PEF- and S-pretreated suspensions was also evaluated. The data evidence that PEF technique allows selective extraction o…

“Ice” juice from apples obtained by pressing at subzero temperatures of apples pretreated by pulsed electric fields

Abstract The impact of apple pretreatment by pulsed electric field (PEF) on juice extraction using the freezing-assisted pressing was studied. Apple discs were PEF pretreated at electric field strength of E  = 800 V/cm and then air blast frozen inside the freezer (− 40 °C). Then, pressing experiments in a laboratory-pressing chamber (2–5 bars) were started at sub-zero temperature (− 5 °C). Time evolution of juice yield and its nutritional qualities were compared for PEF and untreated apple samples. High improvements of juice yield were obtained for freeze-thawed (FT) and PEF + FT samples. The combination of PEF + pressing (5 bar) at sub-zero temperature gave optimum results for juice extrac…

Impact of pulsed electric fields and high voltage electrical discharges on extraction of high-added value compounds from papaya peels

Abstract Extraction of the nutritionally valuable and antioxidant compounds from papaya peels using conventional aqueous extraction (E) (at 20 °C, 50 °C, and 60 °C) and extraction assisted by pulsed electric field (PEF) or by high voltage electrical discharges (HVED) was studied. Increase of extraction temperature or extraction in basic media (pH = 11) not always resulted in an increase of the yields or TEAC values. E.g., the concentration of proteins and TEAC values at pH = 7 and pH = 11 were noticeably smaller at 60 °C as compared to those measured at 50 °C. HVED-assisted technique showed a higher extraction efficiency of high-added value compounds compared to PEF-assisted extraction. E.g…

Pulsed electric field assisted extraction of nutritionally valuable compounds from microalgae Nannochloropsis spp. using the binary mixture of organic solvents and water

Abstract This work studies the potential of the pulsed electric field (PEF) assisted extraction of nutritionally valuable compounds from microalgae Nannochloropsis spp. using the binary mixture of organic solvents (dimethyl sulfoxide, DMSO and ethanol, EtOH) and water. The one-stage (E I ) and two stage (E II ) extraction procedures were compared. The procedure E I included the common extraction using the binary mixtures. Two stage (E II ) extraction procedure involved PEF-treatment (20 kV/cm) of microalgae suspension (1% wt.) and extraction in water as the first step. The second step included the common extraction using the binary mixtures. The effects of extraction procedure and concentra…

Current applications and new opportunities for the use of pulsed electric fields in food science and industry

ABSTRACT Several studies have demonstrated the feasibility of pulsed electric fields (PEF) for different applications in food industry. PEF technology is therefore a valuable tool that can improve functionality, extractability, and recovery of nutritionally valuable compounds as well as the bioavailability of micronutrients and components in a diverse variety of foods. Additionally, other studies have shown the potential of PEF treatments to reduce food processing contaminants and pesticides. This opens the doors to new PEF applications in the food industry. This review focused on some of the most renowned traditional and emerging PEF applications for improvement of osmotic dehydration, ext…

The impact of pulsed electric fields on quality parameters of freeze‐dried red beets and pineapples

Pulsed electric field and mild heating for milk processing: a review on recent advances.

Pulsed electric field (PEF) treatment consists of exposing food to electrical fields between electrodes within a treatment chamber, which can improve the preservation of fresh-like products such as milk. Although several studies support the use of PEF technology to process milk at low temperature, these studies reported microbial reductions of around 3 log10 cycles and also indicated a limited impact of PEF on some endogenous and microbial enzymes. This scenario indicates that increasing the impact of PEF on both enzymes and microorganisms remains a major challenge for this technology in milk processing. More recently, combining PEF with mild heating (below pasteurization condition) has bee…

Electro-biorefinery as a Potential Tool for Valorization of Mango and Papaya By-products

During exotic fruits processing, a large amount of by-products, especially seeds and peels, are produced and discarded into the environment causing organic pollution. However, it is recognized that these by-products are a good source of high-added value compounds, which can be used for different purposes (i.e. food additives and/or nutraceuticals). At this stage of development, there is a lack of information about the different extraction methods that can be used for the recovery of high-added value compounds from papaya and mango by-products. In this line, the extraction assisted by pulsed electric technologies seems to be rather promising. In this research study, the exponential decay pul…