. 2020 Jun 1;9(6):699. doi: 10.3390/foods9060699

Table 1.

The application of pulsed electric field (PEF) treatment for the preservation of functional fruit juices and beverages over the last 5 years.

Juice Type	PEF Conditions	Nutritive/Physicochemical Quality	Microbial Safety	Key Conclusions	Reference
Mango (Mangifera indica Linnaeus) and papaya (Carica papaya Linnaeus) juices with added stevia infusion	Square-wave bipolar pulses, with pulse width of 2.5 μs. 20–40 kV cm⁻¹ 100–360 μs stevia leaf infusion: 0–2.5% (w/v)	-ascorbic acid -total anthocyanins (TA) -total carotenoids (TC) -steviol glycosides -total soluble solid content -CIELab -hydroxymethylfurfural content (HMF)	/	-higher electric field strengths revealed higher ascorbic acid reduction. -higher electric field strengths resulted in stevia beverages with higher TA and TC contents. -the ratio between rebaudioside A and stevioside increased after PEF treatments. -higher electric fields led to significantly higher HMF value. -HMF and color variations were greater in beverages without stevia. -optimum PEF conditions with respect to bioactive compounds: 21 kV cm⁻¹ during 360 μs with 2.5% stevia	Carbonell-Capella et al. (2016) [51]
Sour cherry juice Apricot and peach nectars	Square-wave bipolar pulses with 3 μs duration and 20 μs delaying timeFlow rate: 50 mL min⁻¹ 24 kV cm⁻¹ 125 Hz (66 μs, 8.4 Js⁻¹) 250 Hz (131 μs, 16.8 Js⁻¹) 400 Hz (210 μs, 26.9 Js⁻¹)	-titratable acidity (TA) -electrical conductivity (EC) -Commission Internationale de l’Éclairage LAB (CIELab) -non-enzymatic browning index (BI) -total ascorbic acid content (TAAC) -total β-carotene content (TBC) -total monomeric anthocyanin content (TMAC) -aroma compounds -sensory analysis	/	-PEF treatment did not change 94% of the sensory properties and 64% (sour cherry juice), 60% (apricot nectar), and 30% (peach nectar) of the physical properties. -aroma compounds were affected by. -in all investigated samples. PEF treatment significantly changed 57% of a total of 73 identified aroma compounds. -PEF could be applied with different treatment times for the pasteurization of all investigated samples.	Evrendilek (2016) [52]
Apple juice (unclarified)	Cyclic PEF treatment—each cycle consisted of 50 pulses (one pulse every 30 s). Design of experiments (DOE): −30 kV cm⁻¹ -number of cycles: 4, 6, 8 (total of 200, 300, and 400 pulses, respectively) -storage: 24, 48, and 72 h under refrigeration. T < 35 °C	-total vitamin C content -total polyphenols -antioxidant activity (ABTS)	-Mesophilic and psychrophilic actinomycetes -Microscopic fungi -Yeasts -Enterococci -Salmonella -Staphylococcus aureus	-Regardless of the number of pulses, PEF did not affect the contents of vitamin C or total polyphenols during storage. -PEF treatment and the number of pulses influenced antioxidant activity, which decreased immediately after the treatment and after 24 h of storage. -PEF treatment successfully inactivated food spoilage microorganisms. -increased number of pulses positively affected the reduction in number of studied microorganisms.	Dziadek et al. (2019) [53]
Pinot noir juices (Vitis vinifera L.) obtained at different maceration times (0, 2, 4, 8, and 14 days) after PEF treatments	PEF operating variables: -constant pulse width 20 µs -50 Hz -1.5 kV cm⁻¹ -243 pulses (“PEF Low”) -1033 pulses (“PEF High”) -estimated specific energy inputs were 14.48 ± 0.11 kJ/kg and 69.99 ± 0.52 kJ/kg for “PEF Low” and “PEF High”, respectively T < 25 ± 2 °C	-vitamin C -total phenolic content -malvidin-3-O -glucoside content -DPPH scavenging activity -simulated in vitro human gastrointestinal digestion -cell culture experiments using Caco-2 cell lines -biomarkers for general cellular health and integrity	/	-PEF treatment increased juice yield and preserved intense juice color. -PEF pretreatment of grapes improved the release of malvidin-3-O-glucoside for 224%. -PEF treatment resulted in higher total phenolic content (+61%), vitamin C (+19%), DPPH scavenging activity (+31%), bioprotective capacity (+25% for cell viability and +30% for LDH leakage).	Ying Leong et al. (2016) [54]
Date juice (variety Bou-Hattem)	High-intensity pulsed electric field (HIPEF) operating variables: -bipolar square-wave pulses of 4 µs -35 kV cm⁻¹ -100 Hz for 1000 µs T < 35 °C Thermal treatment at 90 °C for 60 s in a tubularheat exchanger. All samples were stored in darkness for 5 weeks at 4 °C.	-total phenolic compounds -CIELab color measurement -HMF determination -turbidity evaluation -pH -soluble solids determination	/	-HIPEF treatment preserved the nutritive and physicochemical quality of date juices during storage in comparison to thermally treated and control (untreated) samples. -after HIPEF treatment, juices revealed higher amounts of total phenols, which were better preserved during storage than that untreated and thermally processed samples. -HIPEF did not alter the color parameters. -HIPEF treatment reduced HMF content of date juice after processing and during storage in comparison to thermally treated samples. -all investigated physicochemical properties were better-preserved after HIPEF in comparison to thermally processed and control (untreated) samples.	Mtaoua et al. (2016) [55]
Orange juice Watermelon juice Coconut water	All PEF processing conditions werestudied in a continuous-flow system. Moderate-intensity PEF: bipolar square-wave pulses of E = 0.9 and 2.7 kV cm⁻¹ pulse width: τ = 15, 100 or 1000 μs High-intensity PEF (used in industrial applications): monopolar square-wave pulses of E = 10 or 20 kV cm⁻¹ and pulse width τ = 2 μs	/	Escherichia coli Listeria monocytogenes Lactobacillus plantarum Salmonella Senftenberg Saccharomyces cerevisiae	-moderate-intensity PEF was shown to be very effective and easy to scale, and thus could be an alternative for pasteurization of fruit juices. -Optimal PEF conditions, which could match those of pasteurization: E = 2.7 kV cm⁻¹ τ = 1000 μs. -moderate-field PEF can be used for treatment of both high-acid and low-acid products, in contrast to high-intensity PEF, which is only suitable for high-acid products. -moderate-intensity PEF demonstrated slight differences in the degree of inactivation between the different microbial species tested, while high-intensity PEF indicated greater differences between the microbial species.	Timmermans et al. (2019) [56]
Cloudy apple juice	Low-intensity PEF: 12.5 kV cm⁻¹ Flow 27.6 L/h Energy input 76.4 kJ/L Frequency 62 Hz T_inlet 37.6 °C T_outlet 59.5 °C Thermal pasteurization (TP): 72 °C/15 s High-intensity PEF: 12.3 kV cm⁻¹ Flow 24.5 L/hEnergy input 132.5 kJ/L Frequency 94 Hz T_inlet 37.3 °C T_outlet 72.8–73.8 °C Thermal pasteurization (TP): 85 °C/30 s Storage: 3 weeks at 4 °C	-color measurement -turbidity and cloud stability -particle size distribution -polyphenol oxidase (PPO) activity -peroxidase (POD) activity -pectin methylesterase (PME) activity -total soluble solids (TSS) -sugar profile -pH, titratable acidity (TA) -organic acid profile -vitamin C -sensory analysis -volatile compounds		-PEF-treated juices differed from the untreated juice, showing higher lightness (L) and redness (a). -PPO, POD, and PME activities were greatly reduced by high-intensity PEF. -vitamin C and cloud stability decreased during storage. -significant changes in pH, titratable acidity, organic acid, and sugar contents were not observed. -esters noticeably increased in juices after PEF treatments in comparison to TP treatment, where ester degradation reactions occurred together with the formation of off flavors. -increased contents of fructose and glucose and decreased contents of sucrose were observed during storage in all juices.	Wibowo et al. (2019) [57]
Beverages formulated with a blend of fruit juices (orange, kiwi, pineapple, and mango) and water (WB), milk (MB), or soy milk (SB)	-High-intensity pulsed electric field (HIPEF): 35 kV cm⁻¹ 4 μs bipolar pulses at 200 Hz for 1800 μs T < 35 °C Thermal treatment (TT): 90 °C for 1 min)	-in vitro gastrointestinal digestion -individual carotenoids -lipophilic antioxidant activity (LAA) -bioaccessibility	/	-after HIPEF treatment, the contents of several carotenoids increased by between 8% and 28%. -HIPEF was found to be more effective than TT in preserving the concentrations and bioaccessibility of carotenoids and other lipophilic compounds in terms of antioxidant activity of investigated beverages. -the beverage with the highest bioaccessibility of total carotenoids was MB, followed by SB and WB. -milk matrix (MB) in combination with HIPEF improved the bioaccessibility of carotenoids by 15% as compared with the untreated samples. -HIPEF and TT decreased the bioaccessibility of carotenoids in WB. -food matrixes and food processing are able to modify the bioaccessibility of carotenoids.	Rodríguez-Roque et al. (2015) [48]
Beverages formulated with a blend of fruit juices (orange, kiwi, pineapple, and mango) and water (WB), milk (MB), or soy milk (SB)	-High-intensity pulsed electric field (HIPEF): 35 kV cm⁻¹ 4 μs bipolar pulses at 200 Hz for 1800 μs T < 35 °C Thermal treatment (TT): 90 °C for 1 min)	-vitamin C -individual phenolic compounds -total phenolic content (TPC) -hydrophilic antioxidant activity (HAA) -bioaccessibility	/	-HIPEF reduced the content of vitamin C (8%–15%) as compared with untreated samples. -TT negatively affected the stability of vitamin C (losses of 31%) in comparison to untreated samples. -HIPEF did not alter the bioaccessibility of vitamin C in comparison with untreated samples. -significant decrease in the vitamin C bioaccessibility was noticed in TT samples. -HIPEF treatment provoked increased content of several phenolic compounds in MB and SB. -food matrix and processing could modify the bioaccessibility of bioactive compounds	Rodríguez-Roque et al. (2015) [47]
Clarified pomegranate juice (Hicaz cultivar)	pulse duration: 3 µs pulse delay time: 20 µs frequency: 500 pps controlled flow rate: 60 mL min⁻¹ DOE: 0, 17, 23, 30 kV cm⁻¹ 5, 15, 25, 35 °C Total treatment time was estimated at 108.4 µs, with applied energies of 37.5, 50.3, and 65.3 J, respectively.	-pH -CIELab, browning index (BI) -total antioxidant capacity (TAC)–DPPH -total phenolic content (TPC) -total monomeric anthocyanins (TMAC) -total ascorbic acid (TAAC) -sensory evaluation	E. coli O157:H7 (EDL 931 04054) S. aureus (95047)	-electric field strength was the most significant factor in terms of bacterial inactivation. -the inactivation of S. aureus and E. coli O157:H7 in PEF-treated samples reached up to 4.47 and 5.43 log CFU/mL, respectively. -the decreases in the mean initial TAC, TMAC, and TAAC with increased temperature, electric field strength, and energy were not significant. -the sensory properties of flavor, taste, aftertaste, and overall acceptance were not affected by PEF alone or PEF mild heat treatment.	Evrendilek (2017) [45]