Effect of high-pressure carbon dioxide combined with modified atmosphere packaging on the quality of fresh-cut squash during storage.

The study evaluated the application of a novel high-pressure microbial inactivation method combining dense carbon dioxide with modified atmosphere packaging on organic fresh-cut squash (Cucurbita moschata). Approximately 4 g or 32 g of squash was packed in plastic pouches filled with CO to test two different gas-to-product ratios and treated with the high-pressure method at previously optimized process conditions (45 °C, 6.0 MPa and 40 min).

Investigating the Effect of Rosemary Essential Oil, Supercritical CO Processing and Their Synergism on the Quality and Microbial Inactivation of Chicken Breast Meat.

Fresh chicken meat is a very perishable good, even at refrigerated storage conditions, due to psychrophilic microbial growth and physicochemical changes. The present study focuses on the use of rosemary ( L.) essential oil (REO), supercritical CO processing and their synergism to increase the microbial inactivation in chicken breast meat.

Increasing the Safety and Storage of Pre-Packed Fresh-Cut Fruits and Vegetables by Supercritical CO Process.

This work presents a feasibility lab-scale study for a new preservation method to inactivate microorganisms and increase the shelf life of pre-packed fresh-cut products. Experiments were conducted on coriander leaves and fresh-cut carrots and coconut. The technology used the combination of hydrostatic pressure (<15 MPa), low temperature (≤45 °C), and CO2 modified atmosphere packaging (MAP).

The effect of supercritical carbon dioxide on the physiochemistry, endogenous enzymes, and nutritional composition of fruit and vegetables and its prospects for industrial application: a overview.

Consumers have an increasing demand for fruit and vegetables with high nutritional value worldwide. However, most fruit and vegetables are vulnerable to quality loss and spoilage during processing, transportation, and storage. Among the recently introduced emerging technologies, supercritical carbon dioxide (SCCO) has been extensively utilized to treat and maintain fruit and vegetables mainly due to its nontoxicity, safety, and environmentally friendly.

Training in tools to develop quantitative microbial risk assessment along the food chain of Spanish products.

Food safety is a widespread challenge. Every year it is estimated that almost 1 in 10 people in the world fall ill after eating contaminated food resulting in over 400,000 deaths. The risk of outbreaks is higher when consuming ready-to-eat (RTE) products because they are eaten without a further cooking process that could inactivate pathogenic microorganisms.

Promoting the preservation of strawberry by supercritical CO drying.

This work aimed to investigate the supercritical CO (ScCO) drying of strawberries and its effect on enzymatic, chemical and microbial stability. Process conditions influenced the final weight loss (WL), water activity (a) and the inactivation of polyphenol oxidase (PPO) and peroxidase (POD). At 40 °C, an efficient drying (WL > 92 %, a < 0.

Optimization of the Appearance Quality in CO Processed Ready-to-Eat Carrots through Image Analysis.

A high-pressure CO process applied to ready-to-eat food products guarantees an increase of both their microbial safety and shelf-life. However, the treatment often produces unwanted changes in the visual appearance of products depending on the adopted process conditions. Accordingly, the alteration of the visual appearance influences consumers' perception and acceptability.

Effect of CO Preservation Treatments on the Sensory Quality of Pomegranate Juice.

Due to the interest in identifying cost-effective techniques that can guarantee the microbiological, nutritional, and sensorial aspects of food products, this study investigates the effect of CO preservation treatment on the sensory quality of pomegranate juice at t and after a conservation period of four weeks at 4 °C (t). The same initial batch of freshly squeezed non-treated (NT) juice was subjected to non-thermal preservation treatments with supercritical carbon dioxide (CO), and with a combination of supercritical carbon dioxide and ultrasound (CO-US). As control samples, two other juices were produced from the same NT batch: A juice stabilized with high pressure treatment (HPP) and a juice pasteurized at high temperature (HT), which represent an already established non-thermal preservation technique and the conventional thermal treatment.

Research Note: Microbial inactivation of raw chicken meat by supercritical carbon dioxide treatment alone and in combination with fresh culinary herbs.

The objective of the present study was to assess the potential synergistic effect between supercritical carbon dioxide (SC-CO) and fresh culinary herbs (Coriandrum sativum and Rosmarinus officinalis) on the microbial inactivation of raw chicken meat. The microbiological inactivation was performed on Escherichia coli and natural flora (total mesophilic bacteria, yeasts, and molds). High pressure treatments were carried out at 40°C, 80 or 140 bar from 15 to 45 min.

Enzymatic, physicochemical, nutritional and phytochemical profile changes of apple (Golden Delicious L.) juice under supercritical carbon dioxide and long-term cold storage.

The impact of supercritical carbon dioxide (SCCD) (10-60 MPa/45 °C/30 min) and subsequent 10 weeks storage at 4 °C on polyphenol oxidase (PPO), peroxidase (POD) activities, phenolic profile, vitamin C, sugars, physicochemical properties of cloudy apple juices was investigated. No significant changes in sugars and total polyphenols were observed, whereas significant degradation (≈28%) of vitamin C and individual polyphenols (≈18%) was noted after SCCD treatment. After 4 weeks storage only 34% of vitamin C was retained and no vitamin C was detected after this time.

Supercritical CO2 induces marked changes in membrane phospholipids composition in Escherichia coli K12.

Supercritical carbon dioxide (SC-CO2) treatment is one of the most promising alternative techniques for pasteurization of both liquid and solid food products. The inhibitory effect of SC-CO2 on bacterial growth has been investigated in different species, but the precise mechanism of action remains unknown. Membrane permeabilization has been proposed to be the first event in SC-CO2-mediated inactivation.

Comparison of quantitative PCR and flow cytometry as cellular viability methods to study bacterial membrane permeabilization following supercritical CO2 treatment.

Foodborne illness due to bacterial pathogens is increasing worldwide as a consequence of the higher consumption of fresh and minimally processed food products, which are more easily cross-contaminated. The efficiency of food pasteurization methods is usually measured by c.f.

Optimization of supercritical carbon dioxide treatment for the inactivation of the natural microbial flora in cubed cooked ham.

This study aims to investigate the effects of supercritical carbon dioxide (SC-CO₂) treatment on the inactivation of the natural microbial flora in cubed cooked ham. Response surface methodology with a central composite design was applied to determine the optimal process conditions and investigate the effect of three independent variables (pressure, temperature and treatment time). Additionally, analyses of texture, pH and color together with a storage study of the product were performed to determine its microbial and qualitative stability.

Effect of supercritical carbon dioxide pasteurization on natural microbiota, texture, and microstructure of fresh-cut coconut.

The objective of the present study was the evaluation of the effectiveness of supercritical carbon dioxide (SC-CO(2)) as a nonthermal technology for the pasteurization of fresh-cut coconut, as an example of ready-to-eat and minimally processed food. First, the inactivation kinetics of microbiota on coconut were determined using SC-CO(2) treatments (pressures at 8 and 12 MPa, temperatures from 24 to 45 °C, treatment times from 5 to 60 min). Second, the effects of SC-CO(2) on the hardness and microstructure of fresh-cut coconut processed at the optimal conditions for microbial reduction were investigated.

Carbon dioxide induced silk protein gelation for biomedical applications.

We present a novel method to fabricate silk fibroin hydrogels using high pressure carbon dioxide (CO(2)) as a volatile acid without the need for chemical cross-linking agents or surfactants. The simple and efficient recovery of CO(2) post processing results in a remarkably clean production method offering tremendous benefit toward materials processing for biomedical applications. Further, with this novel technique we reveal that silk protein gelation can be considerably expedited under high pressure CO(2) with the formation of extensive β-sheet structures and stable hydrogels at processing times less than 2 h.

Terminal sterilization of BisGMA-TEGDMA thermoset materials and their bioactive surfaces by supercritical CO2.

The development of biomaterials endowed with bioactive features relies on a simultaneous insight into a proper terminal sterilization process. FDA recommendations on sterility of biomaterials are very strict: a sterility assurance level (SAL) of 10(-6) must be guaranteed for biomaterials to be used in human implants. In the present work, we have explored the potential of supercritical CO(2) (scCO(2)) in the presence of H(2)O(2) as a low-temperature sterilization process for thermoset materials and their bioactive surfaces.

Porous poly(D,L-lactic acid) foams with tunable structure and mechanical anisotropy prepared by supercritical carbon dioxide.

The design and tunability of tissue scaffolds, such as pore size and geometry, is crucial to the success of an engineered tissue replacement. Moreover, the mechanical nature of a tissue scaffold should display properties similar to the tissue of interest; therefore, tunability of the foam mechanical properties is desirable. Polymeric foams prepared using supercritical carbon dioxide as a blowing agent has emerged in recent years as a promising technique to prepare porous scaffolds.

High pressure gases: role of dynamic intracellular pH in pasteurization.

Certain dense gases, including CO(2) and N(2)O, are known to deactivate food pathogens safely. Complete deactivation requires disabling intracellular metabolic pathways by extracellular processing that causes membrane disruption, irreversible denaturation of proteins, or extraction of cell contents. At present, neither the precise physical and metabolic mechanisms nor their kinetics behind dense gas pasteurization are known.

Mathematical modeling of yeast inactivation of freshly squeezed apple juice under high-pressure carbon dioxide.

The number of data sets available in literature regarding inactivation kinetic of microorganisms at low temperature, demonstrate an increasing attention to new technologies for food preservation at ambient temperature. Nevertheless, no reliable modeling, capable to describe complex inactivation curves, such as the ones due to dense gas pasteurization with a log-linear behavior, have been developed thus far. In this respect, the main aim of this work is to analyze and model experimental data of dense carbon dioxide yeast pasteurization of natural apple juice at different condition of temperature (25-36°C) and sample volume (5-10 ml).

Determination of extracellular and intracellular pH of Bacillus subtilis suspension under CO2 treatment.

In this study, we consider the effect of carbon dioxide (CO(2)) on the intracellular and extracellular pH of a saline solution of a test-microorganisms Bacillus subtilis. The cytoplasmatic pH was determined by means of a flow cytometry with the fluorescent probe 5(and 6-)-carboxyfluorescein ester (cFSE). The physiological suspension of cells with the addition of the probe was first exposed to high pressure CO(2) for 5 min at different temperatures.

Inactivation of bacteria and spores by pulse electric field and high pressure CO2 at low temperature.

The common methods for inactivation of bacteria involve heating or exposure to toxic chemicals. These methods are not suitable for heat-sensitive materials, food, and pharmaceutical products. Recently, a complete inactivation of many microorganisms was achieved with high-pressure carbon dioxide at ambient temperature and in the absence of organic solvent and irradiation.