Pulsed Electric Field Processing Research Articles

Effect of pulsed electric field processing on microbial and enzyme inactivation in blended plant-based milk alternatives: A case study on a microbial challenge test for a non-presterilized oat-based beverage enriched with pea protein

Microbial and enzyme inactivation by pulsed electric field (PEF) treatment was assessed in a blended plant-based milk alternative (PBMA) containing oats and pea protein without the application of presterilization. This was conducted to investigate a novel approach that permits PEF process validation for PBMA containing heat-labile components (protein and starch). Continuous PEF processing at moderate field strengths (9–10 kV/cm) combined with mild preheating (30–45 °C) for 25 s was applied over a range of specific energy inputs (77–245 kJ/L). Selective plating permitted bacterial enumeration of inoculated surrogate organism, despite the presence of natural microbial contaminants in the non-presterilized product. A minimum 5-log reduction of inoculated surrogates Escherichia coli and Listeria innocua alongside native microbiota was identified after preheating to 35–45 °C followed by PEF at 192–215 kJ/L. α-amylase activity was reduced by up to 89% during a similar PEF treatment (205 kJ/L, 40 °C). Overall, continuous PEF combined with mild preheating temperature was shown to achieve microbial inactivation in the pea protein enriched PBMA in compliance with current food safety regulations. Industrial relevancePresterilization is typically applied prior to conducting microbial challenge testing on food products to validate novel pasteurization treatments according to current regulatory requirements that a minimum 5-log reduction of relevant inoculated food pathogens must be achievable. However, for a variety of blended PBMA containing heat-labile proteins, presterilization is not advisable as the occurrence of irreversible changes in the product quality linked to protein coagulation and phase separation will affect the inactivation efficacy during subsequent microbial challenge testing. Hence, an alternative approach is presented utilizing a non-presterilized PBMA and thorough microbiological analysis, combining non-selective and selective plating techniques. This allows an identification of PEF treatment parameter with a minimum 5-log reduction of inoculated surrogate organism alongside naturally present microbial contaminants. This may serve as a valuable guideline for stakeholders in the food industry when addressing the efficacy of novel preservation treatments such as PEF in PBMA products with similar heat-induced product stability challenges.

Effect of pulsed electric field processing on the quality characteristics and enzyme activity of tender coconut water.

Tender coconut water (TCW) is a natural drink rich in natural electrolytes, minerals, salts and sugars; it has good health benefits. But, its shelf-life is very limited because of the active nature of enzymes present in it when exposed to air. Therefore, the processing of TCW is necessary to inactivate the enzymes. So, this study aims to observe the effect of various process parameters of pulsed electric field (PEF) on the quality parameters of TCW. For the treatment of TCW with PEF, a full-factorial design of experiments was followed with process parameters such as three levels of electric field intensity (8, 12, and 16 kV/cm), two levels of pulse width (PW) (50 and 70 μs), and six levels of the number of pulses (2000 to 12,000 pulses) were considered at a constant pulse OFF time of 75 ms. PEF treatment did not significantly change pH, total soluble solids, and viscosity. However, it significantly affected vitamin C, colour, and total and reducing sugars. PEF treatment significantly enhanced the total phenolic content and antioxidant activity by 23.17% and 42.49%, respectively. At the same time, significant inactivation of polyphenol oxidase (100%) and peroxidase (60.2%) was observed at PEF treatment conditions of 16 kV/cm, 70 μs PW, and 12,000 pulses. Moreover, no significant change in the sensory acceptability of PEF-treated TCW (16 kV/cm, 70 μs PW, 12,000 pulses) when compared to the untreated/fresh TCW, which is a promising sign.

Disentangling the effects of electroporation and heat during pulsed electric field (PEF) processing of oat-based milk alternative: A case study on Lactiplantibacillus plantarum inactivation

The study aimed to quantify the resistance of two L. plantarum strains and estimate the contribution of temperature during the pulsed electric field (PEF) processing of oat beverage. PEF and thermal inactivation kinetic experiments of L. plantarum strains were performed separately. Log10 reductions ≥5.7 of L. plantarum was achieved when 10–24 kV/cm, 110–115 kJ/L, 80–522 μs, and 35 °C inlet temperature were applied, while strain variability was evident in the performed assessments. Accurate monitoring of the temperature profiles for PEF allowed the estimation of the thermal microbial inactivation which was separated from electroporation effect. The electroporation impact was found to increase with increasing electric field strengths. Temperature measurements in the treatment zone confirmed the presence of hot spots. At higher specific energy inputs, there was significant contribution of temperature to the total observed inactivation. This contribution became smaller when the flow rate was increased, as shorter residence time reduced the exposure to high temperature peaks. Industrial relevanceThe findings demonstrated the potential of PEF as a promising technology for the microbial decontamination of oat-based milk alternative. Knowledge of strain variability in response to emerging food processing technologies is critical during process optimisation and quantitative microbial risk assessment. New developments in PEF equipment and process should ideally aim to maximize inactivation while minimizing the impact of high temperature on sensitive food constituents.

Low-intensity pulsed electric fields pre-treatment on yogurt starter culture: Effects on fermentation time and quality attributes

Low-intensity pulsed electric fields (PEF) were applied to a starter culture mix (Streptococcus thermophilus, Lactobacillus bulgaricus, and partially skimmed milk) before the fermentation stage of natural yogurt. The impact of PEF processing conditions on yogurt fermentation time and quality characteristics was evaluated. PEF parameters were set based on a factorial experimental design; independent variables: electric field strength, pulse-frequency, and pulse-width, were explored, having fermentation time as a response. Most PEF treatments reduced fermentation time by 0.31–0.52 h compared to conventional yogurt processing (CY) (4.70 ± 0.23 h). The shortest time (4.18 ± 0.04 h) resulted from PEF pre-treatment with 8-μs monopolar pulses at 1 kV/cm and 150 Hz during 400 μs. The physicochemical and sensory characteristics of PEF-treated yogurt were similar to those of the CY immediately after processing and during refrigeration storage. Low-intensity PEF could be a promising alternative pre-treatment of yogurt production, reducing fermentation time while maintaining quality attributes of natural yogurt. Industrial relevanceConventional yogurt processing lasts around 4.5–6 h, representing high energy consumption and production costs. The application of pulsed electric fields (PEF) processing to the starter culture before yogurt fermentation represents a potential alternative to diminish production time by stimulating lactic acid bacteria and accelerating fermentation stage. This study demonstrated that low-intensity PEF (1–3 kV/ cm) reduced fermentation time by 0.31–0.52 h without compromising yogurt's quality properties, including physicochemical characteristics and sensory attributes. Obtained results suggest that this technology allows more efficient and sustainable yogurt production methods, positively impacting industry and consumers.

Pulsed electric field processing of fruit juices with inactivation of enzymes with new inactivation kinetic model and determination of changes in quality parameters

Pulsed electric fields (PEF) processing of fresh grape, orange and tomato juices by 17.2–24.1 kV/cm electric field strengths, 130.0–1040.5 μs treatment times and 1.43–29.13 J/kg energies with respect to determination of the changes in the physical and bioactive properties, color parameters in addition to inactivation of pectin methyl esterase (PME), polyphenol oxidase (PPO), and lipoxygenase (LOX) enzymes were studied. In general, decrease in pH, increase in conductivity (except for grape juice), total phenolic substance content, and total antioxidant capacity with no significant change (p > 0.05) in total soluble solids were observed by PEF treatment for all juices. Except for hue value for orange juice, no significant changes (p > 0.05) were observed in color values. Inactivation of the enzymes were increased with increased energy, and calculated electrical activation energies for PME, PPO, and LOX enzymes were 8.31, 7.06, and 4.31 kJ/mol, respectively. Industrial relevanceEnzymes in addition microorganisms causing quality degradation is of great concern in fruit juice industry as most of the enzymes are resistant to processing technologies. Increased PEF treatment time provided over 95% inactivation on PME, PPO, and LOX enzymes with no adverse effect on quality properties of grape, orange, and tomato juices revealing a viable alternative to juice processing industry.

Low-intensity pulsed electric field processing prior to germination improves in vitro digestibility of faba bean (Vicia faba L.) flour and its derived products: A case study on legume-enriched wheat bread

This study investigated the effect of low-intensity pulsed electric field (PEF) (0.3–0.7 kV/cm) and/or germination (0–72 h, 20 °C) on faba beans prior to flour- and breadmaking. PEF (0.5 and 0.7 kV/cm) had no significant effect on the germination performance of faba bean but had a positive effect on in vitro starch and protein hydrolysis of PEF-treated beans germinated for 72 h. The incorporation of flour from soaked, germinated, PEF-treated, and PEF-treated+germinated faba beans into wheat bread, at 30% mass level, improved the nutritional composition (total starch and protein contents) and protein digestibility but it reduced the specific volume and increased the density, brownness, and hardness of the bread. This finding shows for the first time that PEF-treatment (<0.7 kV/cm) of faba beans followed by germination (72 h) improved in vitro starch and protein hydrolysis of its flour and the protein digestibility at gastric phase of its enriched wheat bread.

Higher dose makes higher lethality? A dose–response model of pulsed electric fields inactivation from multiscale coarse-graining method

As an emerging technology in liquid inactivation, one of the main challenges of pulsed electric fields (PEFs) inactivation lies in quantitatively describing and predicting its lethality to microorganisms. However, due to its cross-scaled complexity and the consequent numerous regulatory factors, there is currently still no unified framework to understand the PEF dose–response relationship and the population dynamics theoretically. In this study, a simple yet powerful model from multiscale coarse-graining method is proposed to simulate the bacterial inactivation in suspensions during PEF processing. The complex dose–response effects at the macroscale are successfully reconstructed from simple evolution rules and several coarse-graining parameters, while considering the damage and death of a single bacterium at the microscale. Our model uncovers the seemingly chaotic and even controversial dose–response relationship of PEF in literatures and systematically explores the regulatory effect of experimental parameters in a unified framework. One of the interesting findings is that PEF with shorter pulsed width enhances lethality and reduces the minimal inhibitory time at a constant energy output per pulse, owing to the phase transitions in three bacterial population dynamics (Bistability mode, Avalanche mode, and Hybrid mode). Our study provides a new insight for numerically modeling PEF lethality in liquid inactivation and could serve as a guide for dosage management in practical applications.

Pulsed electric field (PEF) processing of microalga Chlorella vulgaris and its digestibility in broiler feed

Microalgae have potentially beneficial effects on animal health and nutritional value when added to feed. Crucial hereby is that intracellular bio-active molecules are released in the intestinal tract. Digestibility of Chlorella vulgaris and its impact on total digestibility of broiler feed is a first step in assessing its characteristics as feed supplement. Different methods could be used to increase the digestibility of the algae. Among other, pulsed electric field (PEF) and freezing to disrupt autotrophic (A) and heterotrophic (H) Chlorella vulgaris cells was assessed to increase their availability followed by in-vivo trials. In these trials effect of algae type (A and H) and effect of PEF-processing was evaluated on the apparent nutrient digestibility. Pulsed electric field showed to have a disruption efficiency of 83.90% and 79.20% for heterotrophic and autotrophic C. vulgaris respectively. Freezing C. vulgaris only showed efficiencies ranging from 3.86 to 11.58%. In the in-vivo trials, microscopic counting of intact C. vulgaris cells showed an increase in digested intact C. vulgaris cells of PEF-processed C. vulgaris compared to nonprocessed cells ranging from 12.16% to 15.20%. Autotrophic C. vulgaris had a higher digestibility compared to heterotrophic C. vulgaris, with an increase of 7.29, 9.44, and 17.29% in digestibility of C. vulgaris in the 1, 2, and 5% feed respectively. Feeds with PEF-processed C. vulgaris showed no significant increase in digestibility compared to nonprocessed C. vulgaris supplemented feeds. The 5% C. vulgaris feeds showed lower fat digestibility than the 1 and 2% and control feeds. Protein digestibility was lower for all C. vulgaris feeds compared to the control feed. There was a significant linear decreasing effect (P < 0.001) for all digestibility parameters. Except for crude ash digestibility, which first lowered for the 1 and 2% feeds, but then increased at 5% inclusion. Considering this study, including low dosages of 1 and 2% of C. vulgaris in broiler feed does not compromise its digestibility.

Evaluation of pulsed electric field and high-pressure processing on the overall quality of refrigerated Concord grape juice

Consumers' demands for minimally processed juices are prompting the expansion of refrigerated, cold-pressed juice market. To develop a nutritious, cold-pressed Concord grape juice, high pressure processing (HPP, 600 MPa, 3 min, 5 °C) and pulsed electric field (PEF, 0.85 kV/cm, 300 pulses) were utilized and the resultant juice was compared with the heat treated (HT, 63 °C, 3 min) juice. HPP was able to preserve the physicochemical properties, reduce microbial load and extend the shelf-life of juice under refrigeration. PEF treatment significantly increased the juice yield (p < 0.01), antioxidants contents and antioxidant activity (p < 0.05). Macroscopic observation indicated that the skin cell structure was altered after PEF. PEF + HPP treated juice had significantly higher purchase intent, appearance and aroma likings (p < 0.05). Combination of PEF and HPP can produce a superior cold-pressed Concord grape juice that meets consumers’ demands for fresh and nutritious fruit juices.

Impact of pulsed electric fields on membrane disintegration, drying, and osmotic dehydration of foods

AbstractDrying is one of the oldest and most conventional methods used to preserve foods. Unique traditional methods have been applied for the drying of plant‐based food products. However, the disadvantage of this approach is the low drying rate, high energy, and processing costs accompanied by the loss of nutritional quality in food products. As a substitute, pulsed electric field (PEF) is a modern and promising technique that has various advantages over thermal treatments. Nowadays, it has become an area of innovation to meet increasing industrial demands. Application of PEF during drying and osmotic dehydration has beneficial impacts on the extension of shelf‐life, increases in storage stability, and improvement of nutritional quality. Upscaling the use of PEF from laboratory to industrial scale while maintaining productivity is an area for further research and development. The aim of this commentary review is to give an overview of a newly proposed PEF process, which improves drying rate, mass‐energy transfer, retention of bioactive compounds, and osmotic dehydration in food. PEF processing led to achieving the innovative development of a wide range of foods and was extended to solve environmental issues. Drying food products is the most promising area in the food industry which needs improvement in terms of achieving energy efficiency and cost‐effectiveness to dry food products with the maintenance of nutritional properties to adequate levels. In this regard, PEF could be a suitable and novel drying method to overcome the limitations of conventional drying methods which might open new horizons for valuable research in manufacturing dried fruits and vegetables on an industrial scale.

Pulsed electric field processing in the dairy sector: A review of applications, quality impact and implementation challenges

SummaryCustomer priority for consuming dairy products with intact natural characteristics is leading the food processing trends towards the extensive exploration of non‐thermal technologies. Pulsed electric field (PEF) technique has arisen as a potential and sustainable processing solution. This review discusses the microbial and enzyme inactivation potential of PEF technique in milk and milk products. Alongside its effect on their natural characteristics. Its potential for better probiotic retention in spray‐dried powders, dairy waste treatment and nutrient enrichment application in dairy products has also been highlighted. PEF has demonstrated its effectiveness in ensuring the dairy product's safety with minimal effects on quality parameters. However, these findings are limited to lab and pilot scale level. Further, extensive research is needed at a commercial scale for the implementation of this technology in the dairy industry.

Investigation of Xinomavro Red Wine Aging with Various Wood Chips Using Pulsed Electric Field

This study explored the potential of pulsed electric field (PEF) as an alternative wine-aging method in four Xinomavro red wines with the implementation of several wood chips (apricot, peach, apple, cherry, acacia, and oak trees). The evolution of total polyphenol content (TPC) and sensory properties of the wines were investigated. Sensory evaluation revealed that PEF treatment increased volatile compound extraction from each wood chip, thereby enhancing the overall quality of the wines. The utilization of acacia tree wood chips in Goumenissa wine led to a notable increase of 10.84% in TPC from the control sample, reaching 2334.74 mg gallic acid equivalents/L. A notable outcome was that PEF decreased TPC, a trend that was also verified through correlation analyses. The highest positive impact of PEF was observed in peach tree wood chips in Goumenissa wine, with a significant increase of 11.05% in TPC. The results from the volatile compound analysis revealed an increase in alcohols and esters from 0.24% to 23.82%, with the highest proportion found in 2-phenylethanol (16.92 mg/L) when utilizing peach tree wood chips in the production of Amyndeo wine. This study could provide a benchmark for rapid, efficient, and cost-effective wine aging through the implementation of the PEF process.

Nutritional Value and Microbiological Aspects of Dried Yellow Mealworm (Tenebrio molitor L.) Larvae Pretreated with a Pulsed Electric Field

Complete protein, which includes all the essential amino acids, and bioactive compounds needed in human nutrition, can be found in edible insects. Bioactive compounds play a crucial role in protecting cells from the damage caused by free radicals. Therefore, in this study, fat extraction yield, protein content, amino acid profile, total polyphenol content, antioxidant properties, crustacean and mollusk content, and microbiological quality have been assessed to evaluate the influence of the drying method and pulsed electric field (PEF) pretreatment. To this end, the sample was processed by the PEF at varied specific energy intakes (5, 20, and 40 kJ/kg) and dried by means of two methods: convective (CD) and infrared-convective (IR-CD). A comparable protein content (47.5–48.7 g/100 g d.m.) was determined for most of the samples tested. A significantly higher lysine and methionine content was detected in the CD insects, especially for samples treated by the PEF at 40 kJ/kg. The IR-CD samples exhibited a significantly higher content of polyphenols as compared to those obtained by means of the CD method, whereas the PEF apparently had a significant impact to the extent of increasing their content. Taking into account allergenicity, the crustacean content was approximately 10 times higher than the mollusk content. The study has shown that the PEF treatment prior to infrared-convective drying resulted in the assurance of the microbiological quality of dried insects for food use. Furthermore, a dose of the PEF at 20 and 40 kJ/kg demonstrated the antimicrobial effect. The results have proven that, in this case, a high temperature during the CD method did not cause the undesirable changes that had been expected. Therefore, PEF-assisted convective drying may conceivably be considered to obtain highly nutritionally valuable insects; however, it is crucial to utilize appropriate parameters in the course of the PEF processing.

Shelf-Life Enhancement Applying Pulsed Electric Field and High-Pressure Treatments Prior to Osmotic Dehydration of Fresh-Cut Potatoes.

From a quality standpoint, it is desirable to preserve the characteristics of fresh-cut potatoes at their peak. However, due to the mechanical tissue damage during the cutting process, potatoes are susceptible to enzymatic browning. This study pertains to the selection of the appropriate osmotic dehydration (OD), high pressure (HP), and pulsed electric fields (PEF) processing conditions leading to effective quality retention of potato cuts. PEF (0.5 kV/cm, 200 pulses) or HP (400 MPa, 1 min) treatments prior to OD (35 °C, 120 min) were found to promote the retention of the overall quality (texture and color) of the samples. The incorporation of anti-browning agents (ascorbic acid and papain) into the osmotic solution improved the color retention, especially when combined with PEF or HP due to increased solid uptake (during OD) as indicated by DEI index (2.30, 1.93, and 2.10 for OD treated 120 min, non-pre-treated, HP pre-treated, and PEF pre-treated samples, respectively). PEF and HP combined with OD and anti-browning agent enrichment are sought to improve the quality and microbial stability of fresh-cut potatoes during refrigerator storage. Untreated fresh-cut potatoes were characterized by color degradation from the 2nd day of storage at 4 °C, and presented microbial growth (total viable counts: 6 log (CFU)/g) at day 6, whereas pre-treated potato samples retained their color and microbiologically stability after 6 days of cold storage (total viable counts, <4 log(CFU)/g).

Quality evaluation of house cricket flour processed by electrohydrodynamic drying and pulsed electric fields treatment

House crickets are expected to play a significant role in the future food sector. Electrohydrodynamic (EHD) drying offers an environmentally friendly alternative to conventional drying methods. Pulsed electric fields (PEF) is a non-thermal process that facilitates conventional processes. EHD was applied to house crickets with and without PEF pretreatment, and the effect of PEF and EHD on the quality of the insects was evaluated. PEF pretreatment positively affected the oven drying at 60 °C by reducing its duration and thus decreasing the energy consumption by 14.22%. Moisture removal of EHD was not sufficient to replace oven drying, but when combined with oven drying, the overall energy consumption was reduced by >50%. PEF processing also increased the protein solubility (53.07% higher than the respective control) and antioxidant activity (24.05% higher than the respective control) of the oven-dried samples and reduced the histamine content of the EHD-dried samples (25.87% lower than the respective control).

Comparative Analysis of Pulsed Electric Fields (PEF) and Traditional Pasteurization Techniques: Comparative Effects on Nutritional Attributes and Bacterial Viability in Milk and Whey Products

With the current upsurge in the desire to foster healthy lifestyles and consume nutritious food products, the food industry has been propelled to develop novel food processing technologies. In our study, we critically evaluated the influence of pulsed electric field (PEF) processing by comparing it to conventional thermal pasteurization protocols—low temperature, long time (LTLT), high temperature, short time (HTST), and microfiltration (MF)—and its ramifications on the nutritional properties inherent in raw milk, which comprises vitamins, whey protein, amino acids, cholesterol, and fatty acids. A significant difference in β-lactoglobulin content was observed in PEF-treated liquid whey samples compared to those treated with high-temperature (HT) pasteurization, where 4.8-fold reduction with a concentration of 0.80 mg/mL was observed. Liquid whey samples treated with PEF, LTLT, HTST and MF retained β-lactoglobulin content, PEF-treated samples yielded 3.85 mg/mL, while HTST, LTLT, and MF-treated samples had β-lactoglobulin content of 3.62 mg/mL, 3.63 mg/mL, and 3.62 mg/mL compared to raw whey control (RWC) at 3.81 mg/mL. The concentrations of nutritional properties, like vitamins (A, D, E), amino acids, cholesterol, and fatty acids, remained approximately consistent across all the pasteurization methodologies. Moreover, the bacterial viability in the context of various pasteurization methodologies was scrutinized, with an absence of colonies observed in whey specimens subjected to thermal pasteurization. PEF-treated samples exhibited a substantial 1.6-log reduction in coliform colony count to less than 4 CFU/mL after curd reduction, in contrast to raw milk samples.

The Effects of Thermal and Pulsed Electric Field Processing on the Physicochemical and Microbial Properties of a High-Fiber, Nutritious Beverage from a Milk-Based Date Powder

The effects of pulsed electric field treatment and thermal pasteurization on the microbial and physical properties of a high-fiber, nutritional milk-based beverage made with date powder were studied. Four ratios of date powder (10, 15, 20, and 25 w/w) were added to the milk, which was then kept at 5 °C for 6 days for the thermal pasteurization and the control treatments. The pulsed electric field treatment had three levels of pulses (20, 50, and 80 pulses) and four ratios of date powder, 10, 15, 20, and 25% (w/w), and then kept at 5 °C for 6 days. The samples were evaluated for the pH, total soluble solids (TSS), total color difference (ΔE), and total viable count (TVC) during their shelf life. The pH values of the beverages in the control treatment were 5.58, 5.45, 5.33, and 5.29 and 6.68, 6.48, 6.26, and 5.87 in the thermal treatment after 6 days, with powder ratios of 10, 15, 20, and 25% (w/w), respectively. The pH values of the beverages in the pulsed electric field treatment were 6.8, 6.64, 6.56, and 6.28 at 80 pulses after 6 days, with powder ratios of 10, 15, 20, and 25% (w/w), respectively. The TVCs in the control treatment were 6.2, 5.44, 4.5, and 3.94 log10 CFU/mL and 4.02, 3.92, 3.54, and 3.31 log10 CFU/mL in the thermal treatment after 6 days, with powder ratios of 10, 15, 20, and 25% (w/w), respectively. The TVCs of the beverages in the pulsed electric field treatment were 1.53, 1.11, 0.665, and 0.511 log10 CFU/mL at 80 pulses after 6 days, with powder ratios of 10, 15, 20, and 25% (w/w), respectively. This shows that following treatment with a pulsed electric field at 80 pulses, a milk-based drink with date powder and no preservatives can be kept at 5 °C for up to 6 days.

Conventional and emerging innovative processing technologies for quality processing of potato and potato-based products: A review

Potatoes are a widely consumed staple food and a key ingredient in numerous food products such as French fries, chips, mashed potatoes and various snacks. The quality of potato products is heavily influenced by the processing methods employed during production. Conventional technologies such as thermal blanching, frying and drying have been widely used for processing potatoes over the years. However, these technologies may lead to the loss of essential nutrients and changes in sensory properties such as texture, color and flavor. In recent years, innovative emerging technologies have been developed to improve potato processing efficiency and product quality while preserving the nutritional and sensory properties of potato products. These technologies include ultrasound processing, pulsed electric field processing, microwave and radiofrequency processing. This review examines the impact of these technologies on the quality attributes of potato products and highlights the importance of selecting appropriate processing technologies for different potato products to achieve the desired quality attributes. In conclusion, this review provides valuable insights into the current trends and advances in the potato processing technologies and emphasizes the need for the continued research and development to optimize these technologies for the production of high-quality potato products. The adoption of emerging technologies has the potential to drive innovation and improve the overall sustainability and efficiency of potato processing, ensuring that potato-based products continue to meet the evolving demands of consumers.

Defining winery processing conditions for the decontamination of must and wine spoilage microbiota by Pulsed Electric Fields (PEF)

This study investigated the PEF-resistance of Saccharomyces bayanus, Brettanomyces bruxellensis, Lactobacillus plantarum, and Oenococus oeni in must or wine under continuous PEF processing. Results showed the capacity of PEF to achieve 3.0-log10-cycles (CFU/mL) of inactivation of all the microorganisms under moderate conditions (< 155 kJ/kg). Developed tertiary models accurately predicted the effect of PEF parameters on microbial inactivation, and Monte Carlo simulation considered the variability of factors and the maximum assumable microbial load in the final treated product. Results showed that PEF-treatments at 15 kV/cm and 129 or 153 kJ/kg would ensure the adequate decontamination (< 10 CFU/mL) of spoilage microorganism in must or wine, respectively. Industrial relevancePEF technology has been shown to achieve adequate levels of microbial inactivation (3-log10) in must and wine under industrial applicable processing parameters, making it a suitable alternative to SO2 or sterilizing filtration for microbial control in winemaking. Reductions of 3-log10 CFU/mL of must and wine microbiota were found by continuous flow PEF-processing at 15 to 25 kV/cm and 175 to 148 kJ/kg, parameters applicable at industrial scale at 1 ton/h.

Physico-chemical and structural modifications of caseins in micellar casein isolate induced by pulsed electric field

The potential of pulsed electric field (PEF) to modify the structure of caseins in micellar casein isolate (MCI) was investigated. MCI was PEF-treated at room (RT, 23 °C) and cold (CT, 4 °C) temperatures, using an electric field strength of 16 kV cm−1 for 6 or 31 μs. Conditions simulating elderly digestion, such as the peptide profile released after gastric digestion and bioactivity, were studied. Unfolding of the protein structure was observed in PEF-treated MCI at RT, which led to cleavage points that were more accessible to enzymes. By contrast, fluorescence emission of tyrosine and tryptophan and Raman spectra indicated a reorganization in the configuration of the micelle in PEF-processed at CT. Under these conditions was observed an increase in the number of peptides generated from gastric digestion compared with untreated MCI, especially the bioactive peptides FSDKIAK f(31–45) and MPFPKYPVEP f(124–133), despite a lower overall uptake of bioactive peptides by Caco-2 cells.Industrial relevance: Micellar casein isolate (MCI) is widely utilized for protein fortification (e.g., in fresh dairy products, smoothies, meat products, and clinical nutrition) and for the adjustment of functional properties in food (e.g., viscosity, foaming). The findings of this work provide valuable information about the potential of PEF processing to modify the properties of MCI.