Hurdle strategies based on high-pressure processing, ultrasonication and pulsed electric field for shelf life extension of refrigerated Asian green mussel

Identification of equivalent processing conditions for pasteurization of strawberry juice by high pressure, ultrasound, and pulsed electric fields processing

Comparing equivalent thermal, high pressure and pulsed electric field processes for mild pasteurization of orange juice. Part I: Impact on overall quality attributes

Shelf life extension of strawberry juice by equivalent ultrasound, high pressure, and pulsed electric fields processes

SO2, high pressure processing and pulsed electric field treatments of red wine: Effect on sensory, Brettanomyces inactivation and other quality parameters during one year storage

Consumers demand healthier fresh tasting foods without chemical preservatives. To address the need, food industry is exploring alternative preservation methods such as high pressure processing (HPP) and pulsed electric field processing. During HPP, the food material is subjected to elevated pressures (up to 900 MPa) with or without the addition of heat to achieve microbial inactivation with minimal damage to the food. One of the unique advantages of the technology is the ability to increase the temperature of the food samples instantaneously; this is attributed to the heat of compression, resulting from the rapid pressurization of the sample. Pulsed electric field (PEF) processing uses short bursts of electricity for microbial inactivation and causes minimal or no detrimental effect on food quality attributes. The process involves treating foods placed between electrodes by high voltage pulses in the order of 20–80 kV (usually for a couple of microseconds). PEF processing offers high quality fresh-like liquid foods with excellent flavor, nutritional value, and shelf life. Pressure in combination with other antimicrobial agents, including CO2, has been investigated for juice processing. Both HPP and PEF are quite effective in inactivating harmful pathogens and vegetative bacteria at ambient temperatures. Both HPP and PEF do not present any unique issues for food processors concerning regulatory matters or labeling. The requirements are similar to traditional thermal pasteurization such as development of a Hazard Analysis Critical Control Point (HACCP) plan for juices and beverages. Examples of high pressure, pasteurized, value added products commercially available in the United States include smoothies, fruit juices, guacamole, ready meal components, oysters, ham, poultry products, and salsa. PEF technology is not yet widely utilized for commercial processing of food products in the United States. The presentation will provide a brief overview of HPP and PEF technology fundamentals, equipment choices for food processors, process economics, and commercialization status in the food industry, with emphasis on juice processing. Paper published with permission.

Comparing the impact of high pressure, pulsed electric field and thermal pasteurization on quality attributes of cloudy apple juice using targeted and untargeted analyses

3 - Food Safety Engineering

The high demand of fresh-like products to meet the fruits and vegetables serving encouraged the implementation of non-thermal food processing techniques, such as high pressure processing (HPP) and pulsed electric fields (PEF), with low impact on nutritional components. The aim of the present work is to evaluate the application of HPP and PEF techniques as useful decontamination tool for aflatoxins (AFs) reduction in grape juice. Spiked grape juice samples with AFs treated by PEF or HPP were extracted using dispersive liquid-liquid microextraction (DLLME) and determined by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS-IT). Reduction percentages of 14–29% have been obtained with both HPP and PEF treatments even higher reductions were obtained for AFB2 and AFG1 under PEF treatment, reaching reduction of 72 and 84% respectively. Results obtained in grape juice samples differed slightly from those obtained in water controls highlighting the matrix effect. Both HPP and PEF techniques showed measurable impact on AFs levels. Furthermore, an AFB2 degradation product obtained after PEF has been identified by quadrupole time of flight mass spectrometry detector (qTOF-MS) and its toxicological endpoints predicted by Pro Tox-II web server.

5 - The environmental impact of pulsed electric field treatment and high pressure processing: the example of carrot juice

The environmental impact of pulsed electric field treatment and high pressure processing: the example of carrot juice

The present study aimed to compare the effects of non-thermal techniques with thermal treatment on physicochemical properties, bioaccessibility, and antioxidant capacity of bioactives in rosehip (Rosa canina) infusions. High pressure processing (HPP) at 200, 400, or 600 MPa for 5 and 15 min; pulsed electric field (PEF) with 5, 10, and 15 kJ/kg specific energy intakes at 1 and 3 kV/cm electric field strength; and thermal treatment (TT) at 85°C/10 min were applied. According to the results, processing method had varying effects on the contents of phenolic compounds, antioxidant capacity, and bioaccessibility in rosehip infusions. The highest retention of total phenolics (TPC) and flavonoids (TFC) were achieved by the TT (2278 mg gallic acid equivalents (GAE)/100 g dry weight (dw) and 3728 rutin equivalents (RE)/100 g dw, respectively) and HPP treatment at a pressure of 600 MPa for 15 min (2268 mg GAE/100 g dw and 3695 mg RE/100 g dw, respectively). These findings are in line with the results of antioxidant capacities of the samples. Besides, TT, HPP treatment at 600 MPa/5 min, and PEF treatment at 5 and 15 kJ/kg energy intakes (PEF1 and PEF3) resulted with a higher recovery of TPC, TFC, and antioxidant capacity after gastrointestinal digestion. It can be concluded that HPP and PEF treatments at specific conditions could be used in the processing of infusions and beverages. However, it should be considered that appropriate processing parameters should be selected and optimized for each sample individually, to assure the best nutritional value and quality characteristics. Novelty impact statement Better retention of bioactive compounds after high pressure processing (HPP) treatment at a pressure of 600 MPa for 15 min. A noticeable improvement in the recovery of bioactive content and antioxidant capacity after HPP and pulsed electric field processing. Potential of non-thermal food processing techniques as alternative to conventional thermal treatments in the production of functional foods with enhanced nutritional value.

IntroductionImpact of processing on product characteristics, sustainability, traceability, authenticity, and public health along the food chain becomes more and more important not only to the producer but also to the customer and the trust of a consumer toward a brand. In recent years, the number of juices and smoothies containing so called super foods or fruits, which have been “gently pasteurized,” has increased significantly. However, the term “gentle pasteurization” related to the application of emerging preservation technologies such as pulsed electric fields (PEF), high pressure processing (HPP) or ohmic heating (OH) is not clearly defined.MethodsTherefore, the presented study investigated the influence of PEF, HPP, OH, and thermal treatment on quality characteristics and microbial safety of sea buckthorn syrup. Syrups from two different varieties were investigated under the following conditions HPP (600 MPa 4–8 min), OH (83°C and 90°C), PEF (29.5 kV/cm, 6 μs, 100 Hz), and thermal (88°C, hot filling). Analyses to test the influence on quality parameters like ascorbic acid (AA), flavonoids, carotenoids, tocopherols, antioxidant activity; metabolomical/chemical profiling (fingerprinting) via U-HPLC-HRMS/MS (here especially flavonoids and fatty acids); sensory evaluation, as well as microbial stability including storage, were conducted.Results and discussionIndependent from the treatment, the samples were stable over 8 weeks of storage at 4°C. The influence on the nutrient content [Ascorbic acid (AA), total antioxidant activity (TAA), total phenolic compounds (TPC), tocopherols (Vit E)] was similar for all tested technologies. Employing statistical evaluation Principal Component Analysis (PCA) a clear clustering based on the processing technologies was observed. Flavonoids as well as fatty acids were significantly impacted by the type of used preservation technology. This was obvious during the storage time of PEF and HPP syrups, where enzyme activity was still active. The color as well as taste of the syrups were found to be more fresh-like for the HPP treated samples.

In this study, the in vitro bioavailability of rosehip infusion phenolics, mainly catechin, as a response to conventional and non-thermal treatments by combining gastrointestinal digestion and a Caco-2 cell culture model, was investigated. After application of thermal treatment (TT, 85 °C/10 min), high pressure (HPP, 600 MPa/5 min) or pulsed electric field (PEF, 15 kJ/kg) processing, all samples were subjected to simulated gastrointestinal digestion. Then, the amount of maximum non-toxic digest ratio was determined by the cytotoxicity sulforhodamine B (SRB) assay. Next, Caco-2 cells were exposed to 1:5 (v/v) times diluted digests in order to simulate the transepithelial transportation of catechin. Results showed that non-thermally processed samples (5.19 and 4.62% for HPP and PEF, respectively) exhibited greater transportation across the epithelial cell layer compared to than that of the TT-treated sample (3.42%). The present study highlighted that HPP and PEF, as non-thermal treatments at optimized conditions for infusions or beverages, can be utilized in order to enhance the nutritional quality of the final products.

The effect of high pressure processing (HPP) (600MPa/15min/56°C) and thermal processing (TP) (95°C/5min) on the quality characteristics of aloe vera-litchi mixed beverage samples (ALMB) stored at 4, 15 and 25°C were studied. The total color difference and browning index of ALMB samples increased with the storage period for both HPP and TP treated samples under all storage conditions. HPP of ALMB resulted in inactivation of pectinmethylesterase (PME), polyphenoloxidase (PPO) and peroxidase (POD) to 34, 65 and 62%, respectively after immediate processing, whereas, TP treatment lead to 83, 79 and 78%, respectively. The residual activity of all the studied enzymes decreased with storage period. The ascorbic acid loss of up to 22% was observed after HPP treatment and up to 31% for thermally treated samples. Minimal changes were noted for phenolics content after HPP as well as thermal processing. The natural microbiota present in samples was below the detection limit (1 log CFU/mL) throughout the storage period. The shelf life of HPP and TP treated samples stored at 4°C was estimated to be 100 and 80days, respectively, based on the sensory quality, ascorbic acid degradation and instrumental color difference.

Effect of information on Chinese consumers’ perceptions and purchase intention for beverages processed by High Pressure Processing, Pulsed-Electric Field and Heat Treatment