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High-pressure Processing (high-pressure + processing)

Distribution by Scientific Domains

Chemistry	40%
Life Sciences	20%
Humanities and Social Sciences	15%

Selected Abstracts

EFFECT OF HIGH-PRESSURE PROCESSING ON TEXTURE AND DRYING BEHAVIOR OF PINEAPPLE

JOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2009
A.R.P. KINGSLY
ABSTRACT The effect of high-pressure processing on texture and drying behavior of pineapple slices was investigated. Pineapple slices were high pressure processed at 50, 100, 300, 500 and 700 MPa at 25C for 10 min. The control, hot water-blanched and high-pressure processed samples were then dehydrated at 70C. Application of high pressure reduced the sample hardness, springiness and chewiness while it had no significant effect on cohesiveness of pineapple. Elevated pressure treatment (,500 MPa) reduced drying time more effectively than for the other pretreated samples. Experimental dehydration data were empirically fitted using six thin-layer drying models. Among the models tested, logarithmic model best described the drying behavior of pineapple slices. The effective moisture diffusivity was found to increase with an increase in the level of pressure up to 500 MPa, and the samples processed at 500 and 700 MPa had higher diffusivity values than blanched samples. PRACTICAL APPLICATIONS This work shows that high-pressure blanching of pineapple can be an alternative for hot water blanching, before dehydration. The results may find application in development of quality snack food from pineapple fruits. [source]

Effect of Pasteurization, High-Pressure Processing, and Retorting on the Barrier Properties of Nylon 6, Nylon 6/Ethylene Vinyl Alcohol, and Nylon 6/Nanocomposites Films

JOURNAL OF FOOD SCIENCE, Issue 1 2009
L. Halim
ABSTRACT:, This study determined the impact of pasteurization, high-pressure processing (HPP), and retorting on the barrier properties of nylon 6 (N6), nylon 6/ethylene vinyl alcohol (N6/EVOH), and nylon 6/nanocomposite (N6/nano) materials. The pasteurized and high-pressure treated films were coextruded with low-density polyethylene (PE) as the heat-sealing layer. The retorted films were coextruded with polypropylene (PP). Oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) of the samples were measured after pasteurization (75 °C for 30 min), HPP (800 MPa for 10 min at 70 °C), and retorting (121 °C for 30 min) treatments. These were compared with the thermal characteristics and morphologies of the samples using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Results showed that OTR of N6 and N6/Nano increased after HPP (16.9% and 39.7%), pasteurization (13.3% and 75.9%), and retorting (63.3% and 112.6%), respectively. For N6/EVOH, a decrease in OTR after HPP (53.9%) and pasteurization (44.5%) was observed. The HPP treatment increased the WVTR of N6 (21.0%), N6/EVOH (48.9%), and N6/Nano (21.2%). The WVTR of N6, N6/EVOH, and N6/Nano increased by 96.7%, 43.8%, and 40.7%, respectively, after pasteurization. The DSC analyses showed that the enthalpy and percent crystallinity increased (2.3% to 6.5%) in the N6/Nano when compared with the N6 material after each treatment. Retorting caused a decrease (3.5%) in the percent crystallinity of the polypropylene material. HPP did not cause major morphological changes to the samples. Results of the barrier studies were influenced by the crystallinity changes in the materials as seen in the XRD diffractograms. [source]

Effect of High-Pressure Processing on Vibrio parahaemolyticus Strains in Pure Culture and Pacific Oysters

JOURNAL OF FOOD SCIENCE, Issue 4 2002
H. Calik
ABSTRACT Different strains of Vibrio parahaemolyticus (Vp) in broth cultures and Vp-inoculated live Pacific oysters (Crassostrea gigas) were subjected to high-pressure processing (HPP) at 241, 276, 310, and 345 MPa. Results showed Vp numbers were reduced by HPP in both pure culture and whole oysters. Vp inactivation was dependent on time and pressure. Optimum conditions for reducing Vp in pure culture and oysters to nondetectable levels were achieved at 345 MPa for 30 and 90 s, respectively. Resistance variations were detected between Vp in pure culture and in oysters. HPP proved to be an efficient means of reducing Vp in oysters. [source]

High-Pressure Processing of Orange Juice: Kinetics of Pectinmethylesterase Inactivation

JOURNAL OF FOOD SCIENCE, Issue 2 2001
U. Nienaber
ABSTRACT: A kinetic study of pectinmethylesterase (PME) inactivation in orange juice was conducted. Juice samples were subjected to combinations of high pressure (400, 500, 600 MPa) and thermal (25, 37.5, 50 °C) treatments for various time periods. PME inactivation followed a first-order kinetic model with a residual activity of pressure-resistant enzyme remaining. Calculated D-values ranged from 4.6 min to 117.5 min at 600 MPa/50 °C and 400 MPa/25 °C, respectively. Pressures in excess of 500 MPa resulted in sufficiently fast inactivation rates for economic viability of the process. [source]

Consumer Awareness and Willingness to Pay for High-Pressure Processing of Ready-to-Eat Food

JOURNAL OF FOOD SCIENCE EDUCATION, Issue 2 2009
Doris T. Hicks
ABSTRACT:, Commercial, nonthermal processing of food, such as high hydrostatic-pressure processing (HPP), has increased. The safety and quality of foods produced by HPP has not been well communicated to the public. An online, nationwide consumer survey was implemented to assess awareness of alternative food processing technologies, consumer food safety attitudes and knowledge, and willingness to pay (WTP) for HPP products. The consumer survey was administered by ZoomerangÔ, an online survey clearinghouse. The survey was completed by 1204 adults. Frequencies and crosstabs were calculated on Zoomerang and SPSS used for one-way ANOVA and chi-square analyses. The survey assessed knowledge of HPP, attitudes about new food processing techniques, WTP for HPP foods and demographics. Overall, many demographic characteristics reflected U.S. census population. While traditional methods, that is, canning, freezing, and microwaving were all well recognized by over 80% of respondents, only 8% recognized HPP. Trends indicated an increase in age, education, and income reflected greater food safety knowledge. Regardless of demographics, no survey respondent exhibited knowledge mastery (80%). Given an explanation of HPP and its benefits, 39% of respondents indicated they would be WTP an additional cost, with higher income and education having the most impact. Majority of respondents indicated a WTP of $0.25 to $0.50 regardless of the value of the food product. More respondents were WTP slightly more for a more expensive product. New technologies often encounter a stumbling block in consumer acceptance and processing costs. A consumer's WTP, once they were informed, could encourage industry to look favorably on this technology. [source]

Modeling Conductive Heat Transfer and Process Uniformity during Batch High-Pressure Processing of Foods

BIOTECHNOLOGY PROGRESS, Issue 1 2000
Siegfried Denys
A numerical model for predicting conductive heat transfer during batch high hydrostatic pressure (HHP) processing of foods was developed and tested for a food simulator (agar gel). For a comprehensive evaluation of the proposed method, both "conventional" HHP processes, HHP processes with gradual, step-by-step pressure buildup and pressure release, and pressure cycling HHP processes were included. In all cases, good agreement between experimental and predicted temperature profiles was observed. The model provides a very useful tool to evaluate batch HHP processes in terms of uniformity of any heat- and/or pressure-related effect. This is illustrated for inactivation of Bacillus subtilis ,-amylase, an enzymatic model system with known pressure-temperature degradation kinetics. [source]

Effects of high-pressure processing on Listeria monocytogenes, spoilage microflora and multiple compound quality indices in chilled cold-smoked salmon

JOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2004
R. Lakshmanan
Abstract Aims:, To evaluate the effect of high-pressure processing (HPP) on Listeria monocytogenes, microbial and chemical changes and shelf-life in chilled cold-smoked salmon (CSS). Methods and Results:, First, challenge tests with L. monocytogenes were carried out using HPP of the product at 0·1 (control), 150, 200 and 250 MPa. Secondly, storage trials with the naturally contaminated product and HPP at 0·1 (control) and 200 MPa were realized. Shelf-life, microbial changes and chemical changes were determined and existing predictive models and multiple compound quality indices evaluated. HPP with 250 MPa did not inactivate L. monocytogenes but significant lag phases of 17 and 10 days were observed at ca 5 and 10°C, respectively. HPP with 200 MPa had a marked effect on both colour and texture of CSS. Conclusions:, High-pressure processing was unable to prevent growth of L. monocytogenes or spoilage of chilled CSS. Existing mathematical models allowed growth rates of L. monocytogenes and shelf-life of samples without high-pressure treatments to be predicted. Significance and Impact of the Study:, High-pressure processing seems more appropriate for new types of salmon products than for a classical product like CSS where consumers expect specific quality attributes. [source]

EFFECT OF HIGH-PRESSURE PROCESSING ON TEXTURE AND DRYING BEHAVIOR OF PINEAPPLE

Effect of Pasteurization, High-Pressure Processing, and Retorting on the Barrier Properties of Nylon 6, Nylon 6/Ethylene Vinyl Alcohol, and Nylon 6/Nanocomposites Films

Effect of Ultra-high-pressure Homogenization on Structure and on Rheological Properties of Soy Protein-stabilized Emulsions

JOURNAL OF FOOD SCIENCE, Issue 9 2002
J. Floury
ABSTRACT: An ultra high-pressure homogenizer (20 to 350 MPa) was used to realize fine food emulsions stabilized by soy proteins. The first aim of the work was to understand how dynamic high-pressure processing affects soybean globulin conformation. Then, the effect of homogenizing pressure on the emulsions structure and rheology was investigated. High-pressure homogenization caused denaturation of proteins due to strong mechanical forces and high temperatures encountered in the valve. Droplet sizes of emulsions were greatly reduced with high-pressure homogenization and Newtonian liquid emulsions were converted into shear-thinning emulsion gels by homogenization at pressures above 250 MPa. Hydrophobic interactions between proteins were supposed to cause the gel-like network structure of emulsions. [source]

Effect of High-Pressure Processing on Vibrio parahaemolyticus Strains in Pure Culture and Pacific Oysters

Effect of high-pressure food processing on the mass transfer properties of selected packaging materials

PACKAGING TECHNOLOGY AND SCIENCE, Issue 5 2010
Maria Jose Galotto
Abstract The effect of high-pressure processing (HPP) on the total migration into distilled water and olive oil and on the barrier properties of four complex packaging materials were evaluated. The films were polyethylene/ethylene-vinyl-alcohol/polyethylene (PE/EVOH/PE), metallized polyester/polyethylene, polyester/polyethylene (PET/PE), and polypropylene-SiOx (PPSiOx). Pouches made from these films were filled with food simulants, sealed and then processed at a pressure of 400,MPa for 30,min, at 20 or 60°C. Pouches kept at atmospheric pressure were used as controls. Prior to and after treatment, all films were evaluated for their barrier properties (oxygen transmission rate and water vapour transmission rate) and ,Total' migration into the two food simulants. In the case of water as the food stimulant, a low ,Total' migration was observed and even a lower one after the HPP treatment. In the case of oil as the food simulant, a higher ,Total' migration was found compared to the control as a result of damage to the structures during the HPP treatment. The gas permeability of the films increased after the HPP, compared to the control, due to damages in the structure caused during the treatment. The PET/PE film presented minimum changes in properties after HPP. Copyright © 2010 John Wiley & Sons, Ltd. [source]

The effect of high-pressure food processing on the sorption behaviour of selected packaging materials

PACKAGING TECHNOLOGY AND SCIENCE, Issue 3 2004
C. Caner
Abstract The sorption behaviour and flavour-scalping potential of selected packaging films in contact with food simulant liquids (FSLs) (ethanol and acetic acid solutions) were evaluated after high-pressure processing (HPP). The films used were monolayer polypropylene (PP), a multilayer (polyethylene/nylon/ethylene vinyl alcohol/polyethylene: PE/nylon/EVOH/PE), film and a metallized (polyethylene terephthalate/ethylene,vinyl acetate/linear low-density polyethylene: metallized PET/EVA/LLDPE) material. D-limonene was used as the sorbate and was added to each of the FSLs. After HPP treatment at 800,MPa, 10,min, 60°C, the amount of D-limonene sorbed by the packaging materials and the amount remaining in the FSL was measured. Untreated controls (1,atm, 60°C and 40°C) were also prepared. Extraction of the D-limonene from the films was performed using a purge/trap method. D-limonene was quantified in both the films and the FSL, using gas chromatography (GC). The results showed that D-limonene concentration, in both the films and the food simulants, was not significantly affected by HPP, except for the metallized PET/EVA/LLDPE. Significant differences in D-limonene sorption were found in comparison with the control pouches. The results also showed that changes in temperature significantly affected the sorption behaviour of all films. Copyright © 2004 John Wiley & Sons, Ltd. [source]

High-pressure processing effects on the mechanical, barrier and mass transfer properties of food packaging flexible structures: a critical review

PACKAGING TECHNOLOGY AND SCIENCE, Issue 1 2004
Cengiz Caner
Abstract Food products can be high-pressure processed (HPP) either in bulk or prepackaged in flexible or semi-rigid packaging materials. In the latter case the packaging material is subjected, together with the food, to high-pressure treatment. A number of studies have been performed to quantify the effects of high-pressure processing on the physical and barrier properties of the packaging material, since the integrity of the package during and after processing is of paramount importance to the safety and quality of the food product. This article reviews the results of published research concerning the effect of HPP on packaging materials. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Influence of high-pressure processing on selected polymeric materials and on the migration of a pressure-transmitting fluid

PACKAGING TECHNOLOGY AND SCIENCE, Issue 5 2002
A. Schauwecker
Abstract This study investigated the migration of 1,2-propanediol (PG) through selected food packaging films exposed to high-pressure processing (HPP). Pouches made from these materials were filled with 95% ethanol as a food-simulating liquid. These packages were then processed using a pilot-scale high-pressure food processor at 400, 600 and 827,MPa and 30, 50 and 75°C for 10,min. Controls were processed at similar temperatures and times, but at atmospheric pressure. To investigate any structural changes to these films during HPP, water was used as the food simulant at temperatures of 30, 75, 85, 90 and 95°C and at pressures of 200, 400, 690 and 827,MPa. No detectable PG migration into the polyester/nylon/aluminium (Al) polypropylene (PP) meal-ready-to eat (MRE)-type pouches was observed. PG migration into the nylon/ethylene vinyl alcohol (EVOH)/PE (EVOH) pouches was similar at 30, 50 and 75°C after 10,min under atmospheric pressure. However, PG migration into the EVOH pouches significantly decreased when treated with high pressure at 30, 50 and 75°C. At 75 and 50°C, the PG migration was significantly higher than the amounts detected at 30°C. Visible signs of delamination between the polypropylene (PP) and aluminum (Al) layers were observed in the MRE pouches processed at ,200,MPa and 90°C for 10,min. This delamination appeared to occur between the PP and Al layers. The differential scanning calorimetric analyses and Fourier transform infrared (FTIR) spectra were similar for the high-pressure treated pouches when compared to their respective controls. This indicated that there were no HPP-induced molecular changes to the treated pouches. Results from this study should be useful to HPP users for predicting PG migration trends and in deciding the selection of appropriate packaging materials for use under similar processing conditions. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Viral Inactivation in Foods: A Review of Traditional and Novel Food-Processing Technologies

COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY, Issue 1 2010
Kirsten A. Hirneisen
ABSTRACT:, Over one-half of foodborne illnesses are believed to be viral in origin. The ability of viruses to persist in the environment and foods, coupled with low infectious doses, allows even a small amount of contamination to cause serious problems. An increased incidence of foodborne illnesses and consumer demand for fresh, convenient, and safe foods have prompted research into alternative food-processing technologies. This review focuses on viral inactivation by both traditional processing technologies such as use of antimicrobial agents and the application of heat, and also novel processing technologies including high-pressure processing, ultraviolet- and gamma-irradiation, and pulsed electric fields. These industrially applicable control measures will be discussed in relation to the 2 most common causes of foodborne viral illnesses, hepatitis A virus and human noroviruses. Other enteric viruses, including adenoviruses, rotaviruses, aichi virus, and laboratory and industrial viral surrogates such as feline caliciviruses, murine noroviruses, bacteriophage MS2 and ,X174, and virus-like particles are also discussed. The basis of each technology, inactivation efficacy, proposed mechanisms of viral inactivation, factors affecting viral inactivation, and applicability to the food industry with a focus on ready-to-eat foods, produce, and shellfish, are all featured in this review. [source]

Control of Listeria monocytogenes Contamination in Ready-to-Eat Meat Products

COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY, Issue 2 2005
Meijun Zhu
ABSTRACT The ubiquitous nature of Listeria monocytogenes and its ability to grow at refrigerated temperature makes L. monocytogenes a significant threat to the safety of ready-to-eat (RTE) meat products. The contamination by L. monocytogenes in RTE meat primarily occurs during slicing and packaging after cooking. The effectiveness of post-package decontamination technology such as in-package thermal pasteurization, irradiation, and high-pressure processing are discussed. Formulating meat products with antimicrobial additives is another common approach to control L. monocytogenes in RTE meat. Irradiation is an effective technology to eliminate L. monocytogenes but can influence the quality of RTE meat products significantly. The effect of irradiation or the combination of irradiation and antimicrobials on the survival of L. monocytogenes and the quality of RTE meat is discussed. [source]