Non-Thermal Preservation of Fruit Juices

ASME 2008 Citrus Engineering Conference ◽

10.1115/cec2008-5404 ◽

2008 ◽

Author(s):

V. M. (Bala) Balasubramaniam

Keyword(s):

United States ◽

High Pressure ◽

Electric Field ◽

Food Industry ◽

Pulsed Electric Field ◽

The United States ◽

High Pressure Processing ◽

Fruit Juices ◽

Microbial Inactivation ◽

Juice Processing

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.

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Selected Quality Parameters of Air-Dried Apples Pretreated by High Pressure, Ultrasounds and Pulsed Electric Field—A Comparison Study

Foods ◽

10.3390/foods10081943 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1943

Author(s):

Artur Wiktor ◽

Aleš Landfeld ◽

Aleksandra Matys ◽

Pavla Novotná ◽

Magdalena Dadan ◽

...

Keyword(s):

High Pressure ◽

Electric Field ◽

Total Phenolic Content ◽

Phenolic Content ◽

Reference Sample ◽

Pulsed Electric Field ◽

Quality Parameters ◽

High Pressure Processing ◽

Total Phenolic ◽

Hygroscopic Properties

The aim of this work was to compare selected physicochemical properties of air dried ‘Golden Delicious’ apples, pretreated either by high-pressure processing (HPP), ultrasound (US) or pulsed electric field (PEF). Following parameters of pretreatment were used: HPP–400 MPa for 15 min, US–21 kHz, 180 W for 45 min, PEF–1 kV/cm, 3.5 kJ/kg. The quality of materials was evaluated by their rehydration properties, hygroscopicity, color and total phenolic content. To compare the effectiveness of the utilized methods, determined properties were expressed as relative comparison values against the reference sample obtained without any pretreatment in the same conditions. The performed research demonstrated that properties can be shaped by the application of proper pretreatment methods. For instance, PEF was shown to be the best method for improving water uptake during rehydration, whereas HPP was the most effective in decreasing hygroscopic properties in comparison with untreated dried apples. Among the investigated methods, HPP resulted in the deepest browning and thus total color difference, while the effects of US and PEF were comparable. For all pretreated dried apples, the total phenolic content was lower when compared with reference material, though the smallest drop was found in sonicated samples.

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Susceptibility of Human Rotavirus to Ozone, High Pressure, and Pulsed Electric Field

Journal of Food Protection ◽

10.4315/0362-028x-65.9.1441 ◽

2002 ◽

Vol 65 (9) ◽

pp. 1441-1446 ◽

Cited By ~ 52

Author(s):

M. A. KHADRE ◽

A. E. YOUSEF

Keyword(s):

High Pressure ◽

Electric Field ◽

Food Processing ◽

Food Industry ◽

Cytopathic Effect ◽

Virus Titer ◽

Pulsed Electric Field ◽

Virus Population ◽

Processing Technologies ◽

Human Rotavirus

The rotavirus causes a food-transmitted gastroenteritis that affects mainly children. Currently, the food industry is interested in alternative food-processing technologies, but research on the control of food-transmitted viruses by these technologies is limited. In this study, the human rotavirus was cultured on MA104 cells, and suspensions of the virus were prepared and treated with ozone, high pressure, and pulsed electric field (PEF). Virus viability was quantified as 50% tissue culture infectious doses (TCID50) per milliliter. Ozone at 25 μg/ml decreased rotavirus infectivity by 8 to 9 log10 TCID50/ml. High pressure was extremely effective against the rotavirus; treatment with 300 MPa for 2 min at 25°C inactivated ~8 log10 TCID50/ml. A small fraction of the virus population, however, remained resistant to pressure treatments of up to 800 MPa for 10 min. Viruses surviving these extreme pressures showed a cytopathic effect different from that of the untreated viruses. The rotavirus was found to be resistant to PEF treatment at 20 to 29 kV/cm, for which no appreciable reductions in virus titer were observed.

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