High Pressure Thermal Sterilization Research Articles

Glucose protects the cell membrane, Na+/K+-ATPase, nucleic acids, and proteins in Bacillus subtilis spores under high pressure thermal sterilization

The extreme resistance of bacterial spores to sterilization makes them a major concern to the food industry and consumers. In this study, the effect of glucose on the inactivation of Bacillus subtilis spores by high pressure thermal sterilization (HPTS) was evaluated. The results showed that the protective effects of glucose increased with the increase in its concentration. Compared with the HPTS control (no addition of glucose), the activity of Na+/K+-ATPase was increased, the leakage of proteins and the release of 2,6-pyridine dicarboxylic acid (DPA) was decreased, and the vibrational strength of the functional group P=O was reduced by the addition of glucose. At the same time, glucose treatment increased the content of α-helix by 6%-22%, while decreased the random coil content by 5%-13% of the cellular protein. In conclusion, the addition of glucose protected the cell membrane, Na+/K+-ATPase, cellular nucleic acids and proteins of B. subtilis under HPTS treatment.

High Pressure Thermal Sterilization and ε-Polylysine Synergistically Inactivate Bacillus subtilis Spores by Damaging the Inner Membrane

This study was conducted to determine the sterilization effect of a combination of high pressure thermal sterilization (HPTS) and ε-polylysine (ε-PL) on Bacillus subtilis spores. The spores were treated with HPTS (550 MPa at 25, 65, and 75°C) and ε-PL at 0.1 and 0.3%. HPTS and ε-PL synergistically decreased the number of surviving spores and increased the release of the intracellular components in the spore suspension, with the maximal effects from treatment with 550 MPa at 75°C plus 0.3% ε-PL. Maximum fluidity and permeability of the cell inner membrane were observed with 550 MPa at 75°C plus 0.3% ε-PL. Changes in membrane lipids were detected from 3,000 to 2,800 cm-1 by Fourier transform infrared spectroscopy. The results provide new insights into the mechanism by which HPTS and ε-PL synergistically sterilize B. subtilis spores.

High pressure thermal sterilization of barramundi ( Lates calcarifer ) muscles in brine: Effects on selected physicochemical properties

Barramundi (Lates calcarifer) muscle with brine 2% in Stand-up-retort pouches was treated at different temperatures from 90°C to 120°C at 600 MPa, 5 min. Samples retorted with Fo = 3.38 min were used as control. Texture attributes such as hardness and springiness of the high pressure thermal sterilized (HPTS) barramundi samples were increased compared to the retorted samples. Color, TBA, and pH values were similar for all treatments, except for a significant increase in pH of samples treated at 90°C, 600 MPa, 5 min after 3 months of storage, indicating microbial spoilage. Textural sensory quality of HPTS products was also better than retorted products. High pressure thermal sterilization (HPTS) at 600 MPa and 110°C or 120°C for 5 min resulted in shelf-stable barramundi products. Overall, HTPS could be a feasible option for the production of sterilized fish product with better texture compared to conventional retorted fish product. Practical applications High pressure and thermal sterilization (HPTS) of food products is emerging as an innovative method with many advantages. HPTS could result in better nutrition and sensory quality of sterilized food products as lower thermal load applied to the product and less unwanted food processing contaminants such as furan are also produced in food products. However, the application of HPTS on food products, especially, seafood products is still in early stage and limited. The result of this study could be used to develop a scale-up process for sterilized barramundi products in the food industry.

Gentle Sterilization of Carrot-Based Purees by High-Pressure Thermal Sterilization and Ohmic Heating and Influence on Food Processing Contaminants and Quality Attributes.

Pressure-enhanced sterilization (PES) and ohmic heating (OH) are two emerging sterilization techniques, currently lacking implementation in the food industry. However, both technologies offer significant benefits in terms of spore inactivation using reduced thermal intensity in food products, as well as minimized effects on sensory and nutritional profiles. In this study, PES and OH were tested based on possible food safety process windows in comparison to thermal retorting, to optimize the food quality of carrot-based purees. The following parameters related to food quality were tested: texture, carotenoid content, color, and detectable amount of food processing contaminants (FPC) formed. Application of the innovative sterilization techniques resulted in a better retention of color, texture, and carotenoids (for PES) as well as a reduced formation of food processing contaminants. Importantly, a significant reduction in the formation of furan and its derivates was observed, compared to the retorted samples. Hence, both sterilization technologies showed promising results in the mitigation of potential toxic processing contaminants and retention of quality attributes.

Formation of furan in baby food products: Identification and technical challenges

Furan is generally produced during thermal processing of various foods including baked, fried, and roasted food items such as cereal products, coffee, canned, and jarred prepared foods as well as in baby foods. Furan is a toxic and carcinogenic compound to humans and may be a vital hazard to infants and babies. Furan could be formed in foods through thermal degradation of carbohydrates, dissociation of amino acids, and oxidation of polyunsaturated fatty acids. The detection of furan in food products is difficult due to its high volatility and low molecular weight. Headspace solid-phase microextraction coupled with gas chromatography/mass spectrometer (GC/MS) is generally used for analysis of furan in food samples. The risk assessment of furan can be characterized using margin of exposure approach (MOE). Conventional strategies including cooking in open vessels, reheating of commercially processed foods with stirring, and physical removal using vacuum treatment have remained unsuccessful for the removal of furan due to the complex production mechanisms and possible precursors of furan. The innovative food-processing technologies such as high-pressure processing (HPP), high-pressure thermal sterilization (HPTS), and Ohmic heating have been adapted for the reduction of furan levels in baby foods. But in recent years, only HPP has gained interest due to successful reduction of furan because of its nonthermal mechanism. HPP-treated baby food products are commercially available from different food companies. This review summarizes the mechanism involved in the formation of furan in foods, its toxicity, and identification in infant foods and presents a solution for limiting its formation, occurrence, and retention using novel strategies.

Continuous Versus Discontinuous Ultra-High-Pressure Systems for Food Sterilization with Focus on Ultra-High-Pressure Homogenization and High-Pressure Thermal Sterilization: A Review.

High-pressure thermal sterilization (HPTS) and ultra-high-pressure homogenization (UHPH) are two emerging sterilization techniques that have not been implemented in the food industry yet. The two technologies apply different acting principles as HPTS uses isostatic pressure in combination with heat whereas UHPH uses dynamic pressure in combination with shear stress, cavitation, impingement, and heat. Both technologies offer significant benefits in terms of spore inactivation in food production with reduced thermal intensity and minimized effects on sensory and nutritional profiles. These benefits have resulted in relevant research efforts on both technologies over the past few decades. This state of the art of the discontinuous HPTS-based and the continuous UHPH-based sterilization concepts are assessed within this review. Further, various basic principles and promising future preservation applications of HPTS and UHPH for food processing, that are also applicable in the pharmaceutical, biochemical, and biotechnological sectors, are summarized. In addition, the applications and limitations of these technologies in terms of optimizations needed to overcome the identified challenges are emphasized.

Ultra high pressure homogenization (UHPH) inactivation of Bacillus amyloliquefaciens spores in phosphate buffered saline (PBS) and milk.

Ultra high pressure homogenization (UHPH) opens up new areas for dynamic high pressure assisted thermal sterilization of liquids. Bacillus amyloliquefaciens spores are resistant to high isostatic pressure and temperature and were suggested as potential surrogate for high pressure thermal sterilization validation. B. amyloliquefaciens spores suspended in PBS buffer (0.01 M, pH 7.0), low fat milk (1.5%, pH 6.7), and whole milk (3.5%, pH 6.7) at initial concentration of ~106 CFU/mL were subjected to UHPH treatments at 200, 300, and 350 MPa with an inlet temperature at ~80°C. Thermal inactivation kinetics of B. amyloliquefaciens spores in PBS and milk were assessed with thin wall glass capillaries and modeled using first-order and Weibull models. The residence time during UHPH treatments was estimated to determine the contribution of temperature to spore inactivation by UHPH. No sublethal injury was detected after UHPH treatments using sodium chloride as selective component in the nutrient agar medium. The inactivation profiles of spores in PBS buffer and milk were compared and fat provided no clear protective effect for spores against treatments. Treatment at 200 MPa with valve temperatures lower than 125°C caused no reduction of spores. A reduction of 3.5 log10CFU/mL of B. amyloliquefaciens spores was achieved by treatment at 350 MPa with a valve temperature higher than 150°C. The modeled thermal inactivation and observed inactivation during UHPH treatments suggest that temperature could be the main lethal effect driving inactivation.

High pressure treated Bacillus subtilis spores — Structural analysis by means of synchrotron and laboratory based soft X-ray microscopy

Abstract Measurements were carried out on high pressure treated (HPT) bacterial endospores of the Bacillus subtilis strain PS832 by means of laboratory (LTXM) and synchrotron based transmission soft X-ray microscopy (SynchTXM). Using LTXM at 500 eV HPT spores could be identified by a higher transparency, due to dipicolinic acid (DPA) release from the spore's core, and their shriveled appearance caused by air-drying. Dormant spores were investigated at different photon energies at SynchTXM. Inner structures were visualized and it was shown that at a photon energy of 280 eV the micrographs yielded bigger absorption differences, and thus better contrast between the core/coat and the peptidoglycan-rich cortex. Tilt series of dormant and HPT spores were reconstructed. Virtual sections revealed the dormant spores' core, cortex and coat without the need to physically slice the sample. It was also possible to visualize the inside of the HPT spores, which proved to be void of DPA. Industrial relevance Isostatic high pressure processing (HPP) is often regarded as the major recent technological innovation in food preservation. However, this technology is only applied in large scale for pasteurization and not for sterilization, which is largely due to the unknown inactivation mechanisms of highly resistant bacterial endospores. The structural analysis of high pressure treated endospores by X-ray microscopy could be used to study the progress of spore germination and inactivation under pressure and may add to the information already gathered in previous studies such as (Reineke et al., 2013) to establish the high pressure thermal sterilization at industrial scale. This technology in combination with different extrinsic factors like chemical or thermal preservation may open up new possibilities for a multi-target spore inactivation strategy for food sterilization.

The impact of high pressure thermal sterilization on the microbiological stability and formation of food processing contaminants in selected fish systems and baby food puree at pilot scale

To this day there is no implementation of the high pressure thermal sterilization (HPTS) in the food industry. HPTS could result in better food quality, lower thermal load applied to the product and less unwanted food processing contaminants (FPCs) such as furan.Based on findings for selected foods at lab-scale extrapolated temperature-time combinations for a 12 log10 inactivation of Bacillus amyloliquefaciens were chosen for a scale-up with a 55 L vessel (HPHT system Hiperbaric). Temperature-time-combinations at 600 MPa were between 100 and 115 °C and 0.45–28min. The scale-up resulted in a reduction of furan, depending on the food system, between 41 and 98% to retorting. Results at pilot scale were similar to lab-scale experiments. The performed storage trials (standardized method NF V 08-408) showed that only for the baby food puree two selected treatment conditions (107.5 °C, 9.8 min and 115 °C, 0.45 min at 600 MPa) resulted in an unstable product. Overall the results of the scale-up process support the idea that the HPTS could be feasible for the implementation in the food industry.

Comparing the impact of high pressure high temperature and thermal sterilization on the volatile fingerprint of onion, potato, pumpkin and red beet

This work reports the effect of high pressure high temperature (HPHT) processing as compared to thermal processing on the volatile fraction of four, industrially-relevant, vegetables: onion, potato, pumpkin and red beet. The vegetables were selected from different botanical families, edible plant parts and color groups, aiming for investigation of a wide range of chemical reactions. Despite the difference in chemical composition among these vegetables, some remarkable general trends could be found. Firstly, in all vegetables, Strecker degradation products (such as 2- and 3-methylbutanal) were detected at higher levels after HPHT sterilization in comparison to thermally sterilized counterparts. Secondly, HPHT sterilization enhanced oxidative degradation reactions (e.g. unsaturated fatty acids (in pumpkin, red beet and onion) and carotenoids (in pumpkin)). This work demonstrated the power of the untargeted multi-variate fingerprinting approach as a fast screening tool to zoom into relevant reaction pathways out of a complex network of chemical changes and to determine discriminative volatiles which can serve as potential markers.

Effect of high pressure thermal sterilization on the formation of food processing contaminants

Abstract The use of high pressure thermal sterilization (HPTS) as an emerging technology for the sterilization of foods could be a big turning point in the food industry. HPTS can result in a better overall food quality, lower thermal load applied to the product and less unwanted food processing contaminants (FPCs) as e.g. furan and monochloropropanediol/-esters. Hence, within the EU FP7 founded Prometheus-project HPTS treatments were performed for selected food systems. Therefore, two spore strains were tested, the Geobacillus stearothermophilus and the Bacillus amyloliquefaciens, in the temperature range from 90 to 121 °C at 600 MPa. The treatments were carried out in different fish system and ACES-buffer. The treatment at 90 and 105 °C showed that the G. stearothermophilus is more pressure sensitive than the B. amyloliquefaciens. The formation of FPCs was monitored during the sterilization process and compared to the amounts found in retorted samples of the same food systems. Depending on the food system the amounts of furan could be reduced between 71 and 97% for the tested temperature pressure combination even at sterilization conditions of F0-value 7 min. Industrial relevance The high pressure thermal sterilization (HPTS) process is an emerging technology to produce high quality low acid food products, which are shelf-stable at ambient temperature. In addition the consumer today demands foods which are minimally processed and are healthy and safe. However, an industrial scale process has not yet been implemented. The work in this paper shows different temperature combinations (90 to 121 °C) at 600 MPa and their influence on the endospore inactivation and also on the formation of unwanted food process contaminants (FPCs), such as furan and monochloropropanediol/-esters, in comparison to retorting. The use of HPTS could lead to shorter process times and a means by which a better quality of the foods could be achieved.

The release of dipicolinic acid — The rate-limiting step of Bacillus endospore inactivation during the high pressure thermal sterilization process

High pressure combined with elevated temperatures can produce low acid, commercially sterile and shelf-stable foods. Depending on the temperature and pressure levels applied, bacterial endospores pass through different pathways, which can lead to a pressure-induced germination or inactivation. Regardless of the pathway, Bacillus endospores first release pyridine-2,6-dicarboxylic acid (DPA), which contributes to the low amount of free water in the spore core and is consequently responsible for the spore's high resistance against wet and dry heat. This is therefore the rate-limiting step in the high pressure sterilization process. To evaluate the impact of a broad pressure, temperature and time domain on the DPA release, Bacillus subtilis spores were pressure treated between 0.1 and 900MPa at between 30 and 80°C under isothermal isobaric conditions during dwell time. DPA quantification was assessed using HPLC, and samples were taken both immediately and 2h after the pressure treatment. To obtain a release kinetic for some pressure–temperature conditions, samples were collected between 1s and 60min after decompression. A multiresponse kinetic model was then used to derive a model covering all kinetic data.The isorate lines modeled for the DPA release in the chosen pressure–temperature landscape enabled the determination of three distinct zones. (I) For pressures <600MPa and temperatures >50°C, a 90% DPA release was achievable in less than 5min and no difference in the amount of DPA was found immediately 2h after pressurization. This may indicate irreversible damage to the inner spore membrane or membrane proteins. (II) Above 600MPa the synergism between pressure and temperature diminished, and the treatment temperature alone dominated DPA release.(III) Pressures <600MPa and temperatures <50°C resulted in a retarded release of DPA, with strong increased differences in the amount of DPA released after 2h, which implies a pressure-induced physiological like germination with cortex degradation, which continues after pressure release. Furthermore, at 600MPa and 40°C, a linear relationship was found for the DPA release rate constants ln(kDPA) between 1 and 30min.

Structural analysis of high pressure treated Bacillus subtilis spores

Abstract The aim of this study was to investigate the internal structural changes in high pressure treated Bacillus subtilis spores and to correlate these changes with results from plate counts, flow cytometry and analysis of dipicolinic acid (DPA) release. For the scanning electron microscopic (EM) evaluation, a focused ion beam sectioning method was developed and compared with transmission EMs. Based on this set of methods, a mechanism was proposed in which 150 MPa at 37 °C induces a physiological-like DPA release, followed by degradation of the cortex and the DNA-binding small acid-soluble proteins (SASPs). Sectioned spores looked like hollow spheres and were inactivated prior to outgrowth. A pressure increase to 550 MPa retarded completion of germination and a porous internal network structure was visible by scanning EM, possibly indicating the lack of SASPs degradation. Higher pressures (600–900 MPa) and temperatures (60–80 °C) may inhibit the degradation of the spore cortex. Industrial relevance The high pressure thermal sterilization (HPTS) process is an emerging technology to produce high quality low acid food products, which are shelf-stable at ambient temperature. However, an industrial scale process has not yet been implemented. The mechanisms suggested in this paper may help to understand the mechanisms of inactivation of bacterial spores treated with various pressure and temperature combinations. In addition, a focused ion beam milling procedure was developed that enables the analysis of internal structure changes in bacterial endospores. These three-dimensional scanning electron micrographs (EMs), which have a reasonable resolution, could allow individual spore tomography, and not only for pressure treated spores.

Inactivation of Bacillus subtilis spores by combining high-pressure thermal sterilization and ethanol

High-pressure thermal sterilization (HPTS) is a new and promising sterilization technology of foods. Effects of combining HPTS and ethanol treatment on inactivation of Bacillus subtilis spores were investigated. An interesting phenomenon was observed. The inactivation effect of HPTS treatment on the spores was enhanced significantly with the increase in ethanol concentration from 0 to 15%. However, the inactivation effect was decreased with further increase in ethanol concentration up to 70%. In addition, the release of DPA and leakages of OD260 and OD280 material from the spores increased continuously with the increase in ethanol concentration. Moreover, flow cytometry analysis suggested that although the inner membrane of the spores was damaged, PI could not bind with the spore DNA immediately after HPTS treatment. In conclusion, the mechanism of this special phenomenon could be attributed to the germination of spores under HPTS treatment and effects of ethanol on the protein or water activity. HPTS caused other lethal damages to the spores besides its damage to the inner membrane. Ethanol of low concentrations could significantly enhance the sterilization effects of HPTS, which was good for keeping the qualities of foods.

Shelf-Stable Egg-Based Products Processed by High Pressure Thermal Sterilization

Producing a thermally sterilized egg-based product with increased shelf life without losing the sensory and nutritional properties of the freshly prepared product is challenging. Until recently, all commercial shelf-stable egg-based products were sterilized using conventional thermal processing; however, this heat treatment was problematic as quality attributes of the product were negatively affected. Combining high pressure with high temperature is a potential alternative to retorting for the production of shelf-stable egg-based products. This review discusses the challenges of high pressure thermal sterilization as an alternative processing method of producing shelf-stable egg products. Attention is given to product improvement in terms of overall quality through modification of ingredients, formulation, processing and packaging, offering the industry a practical way to produce egg-based products with increased shelf life and appealing quality to the consumer.

The different pathways of spore germination and inactivation in dependence of pressure and temperature

Bacillus subtilis spores (PS832) and isogenic strains, which lack the germinant receptors (FB114 and FB115), were treated up to 24 h between 100 and 700 MPa and 30–80 °C to improve the understanding of spore inactivation during the high pressure thermal sterilization. Flow cytometry was used to analyze the physiological state of the spores after pressure-treatment. A two step kinetic model was capable to derive a global model with an acceptable fit for all strains. The kinetic data demonstrated that spore germination without germination receptors is possible even at 300 MPa and no inactivation occurred up to 700 MPa and 50 °C. Contrary for PS832, a spore inactivation of more than 3 log 10 was detected at 300 MPa, whereas no inactivation was observed at 550 MPa and moderate temperature. Possibly, spores with nutrient receptors could proceed through stage II of germination at low pressure levels, whereas this step is retarded at higher pressures. The high pressure thermal sterilization (HPTS) is an emerging technology to reduce the thermal load of a sterilized food product, which consequently increases its sensorial and nutritional quality. However, an industrial installation of this promising technology has not been implemented, yet. An improved understanding of the underlying inactivation mechanisms of bacterial spores may contribute to an optimization of this process. The kinetic data of the current manuscript proves that a significant spore inactivation is possible at moderate treatment pressures and temperatures for long pressure dwell times. However, for a full spore inactivation in an economical treatment time, high pressures and elevated temperatures are needed. For B. subtilis a threshold pressure of 600 MPa was identified, whereas above this pressure the process temperature dominates the inactivation rate. Furthermore, the used two step kinetic model, applied for different kinetic data sets showed an excellent fit in the shared pressure–temperature range, which confirms that inactivation data derived under isothermal isobaric conditions could be transferred to other HP units. ► Spore germination is possible without nutrient receptors even at 200 MPa. ► Spores treated at pressure ≤ 400 MPa possibly proceed through germination stage II. ► To germinate the entire spore population high pressures and temperatures are needed. ► A two step kinetic model was capable to derive a global model for all spore strains. ► Kinetics from isothermal isobaric conditions could be transferred to other HP units.

The Impact of High Pressure and Temperature on Bacterial Spores: Inactivation Mechanisms of Bacillus subtilis above 500 MPa

High-pressure thermal sterilization (HPTS) is an emerging technology to produce shelf stable low acid foods. Pressures below 300 MPa can induce spore germination by triggering germination receptors. Pressures above 500 MPa could directly induce a Ca+2-dipicolinic acid (DPA) release, which triggers the cortex-lytic enzymes (CLEs). It has been argued that the activated CLEs could be inactivated under HPTS conditions. To test this claim, a wild-type strain and 2 strains of Bacillus subtilis spores lacking germinant receptors and one of 2 CLEs were treated simultaneously from 550 to 700 MPa and 37 to 80 C (slow compression) and at 60 to 80 C up to 1 GPa (fast compression). Besides, an additional heat treatment to determine the amount of germinated cells, we added TbCl3 to detect the amount of DPA released from the spore core via fluorescent measurement. After pressure treatment for 120 min at 550 MPa and 37 °C, no inactivation was observed for the wild-type strain. The amount of released DPA correlated to the amount of germinated spores, but always higher compared to the belonging cell count after pressure treatment. The release of DPA and the increase of heat-sensitive spores confirm that the inactivation mechanism during HPTS passes through the physiological states: (1) dormancy, (2) activation, and (3) inactivation. As the intensity of treatment increased, inactivation of all spore strains also strongly increased (up to -5.7 log10), and we found only a slight increase in the inactivation of one of the CLE (sleB). Furthermore, above a certain threshold pressure, temperature became the dominant influence on germination rate. The continuous increase of high-pressure (HP) research over the last several decades has already generated an impressive number of commercially available HP pasteurized products. Furthermore, research helped to provoke the certification of a pressure-assisted thermal sterilization process by the U.S. FDA in February 2009. However, this promising sterilization technology has not yet been applied in industrial settings. An improved understanding of spore inactivation mechanisms and the ability to calculate desired inactivation levels will help to make this technology available for pilot studies and commercialization at an industrial scale. Moreover, if the synergy between pressure and elevated temperature on the inactivation rate could be identified, clarification of the underlying inactivation mechanism during HP thermal sterilization could help to further optimize the process of this emerging technology.

Packaging under pressure: Effects of high pressure, high temperature processing on the barrier properties of commonly available packaging materials

Abstract High pressure thermal (HPT) processing has the potential to deliver quality benefits to a range of processed foods. By exploiting the rapid temperature increase/decrease that accompanies pressurization/depressurization, commercial sterilization of foods can potentially be achieved by HPT with an overall reduced thermal exposure compared with conventional thermal processing technologies. High pressure thermal sterilization (HPTS) of foods is yet to be commercialized, but during development of the technology some potential limitations have been raised about the suitability for HPTS of commercially available packaging materials developed for retort processing. Key requirements of packaging materials for thermally processed foods are the preservation of oxygen and water barriers during processing and for the duration of the shelf life of the food. We examined the barrier properties after HPT processing of eleven commercially available packaging materials developed for conventional thermal sterilization processes. We found that the barrier properties of vapor-deposited oxide and nylon containing films were compromised by the combination of high pressure (600 MPa) and high temperature (∼ 110 °C) which would be reasonably expected to be required to render food commercially sterile by HPT processing. However, the barrier properties of aluminium foil and PVDC–MA containing films were not significantly affected by HPT processing. All materials suffered cosmetic deformation of the outer surface to some degree and mechanisms for these changes are proposed. Industrial relevance Information on the barrier properties of flexible packaging suitable for foods sterilized by HPT processing has been scarcely reported. This study provides information on the barrier properties of commercially available, retortable films processed under high pressure/high temperature conditions and identifies candidate packaging based on barrier performance.

High pressure thermal sterilization – development and application of temperature controlled spore inactivation studies

High pressure thermal sterilization is an emerging technology that can produce uniform, minimally processed foods of high quality, better than heat treatment alone. At present, it has not yet been successfully introduced into the food industry, possibly due to the less known inactivation mechanism of high resistant bacterial spores. This study developed and used a new analytical tool to improve the understanding of spore mechanisms at high pressures and temperatures. The generated data were exemplarily incorporated into analyses of industrial sterilization processes. An improved understanding of the mechanisms of spore inactivation will aid in the food safety assessment of high pressure thermal sterilization in particular, and also assist in the commercialization of this novel process, facilitating adoption by industry.