Non-thermal Process Research Articles

Green synthesis of gold nanoparticles using Curcuma pseudomontana isolated curcumin: Its characterization, antimicrobial, antioxidant and anti- inflammatory activities

Green synthesis of gold nanoparticles (AuNPs) has garnered fervent interest due to their implicit biomedical applications. This study reveals the green synthesis of AuNPs and co-functionalization with Curcuma pseudomontana isolated curcumin (CUR). Synthesized curcumin capped nanoparticles (CUR-AuNPs) were stable and evaluated by SEM, HR-TEM, UV–vis and FT-IR spectroscopy and they were spherical in shape, homogenous with an average diameter of 20 nm along with long term stability. The CUR-AuNPs were tested for their antibacterial activity against Pseudomonas aeruginosa , Staphylococcus aureus , Bacillus subtilis and Escherichia coli and displayed significant antibacterial activity. CUR-AuNPs showed maximum inhibition efficiency of 94% by the human red blood cell method. CUR-AuNPs also exhibited significant antioxidant and radical scavenging activities. This study sets a platform for novel synthetic AuNPs formed by utilizing reducing agents in form of isolated curcumin to effectively exploit the biomedical application of the particles. • CUR-AuNPs were synthesized by CUR isolated from C. pseudomontana around 30 min. Via one-pot non-thermal process. • CUR-AuNPs exhibited excellent stability, homogeneity and around 20 nm in size. • CUR-AuNPs showed effective antibacterial, anti-inflammatory and antioxidant effects. • CUR-AuNPs can be used in various biomedical applications.

EFFECT OF IRRADIATION ON FOOD SAFETY AND QUALITY

Numerous processing techniques have been developed to control food spoilage and raise food safety. The traditional methods of preservation include: pasteurization, canning, freezing, refrigeration and use of chemical preservatives. Food irradiation is non-thermal food preservation process. It is a treatment of food exposition on an amount of energy in the form of speed particles or rays. Depending on absorbed radiation dose, various effects can be achieved, resulting in reduced storage losses, extended shelf life, improved microbiological and parasitological safety of foods. The potential application of ionizing radiation in food processing is based mainly on the fact that ionizing radiations damage very effectively the DNA molecules. The application is very diverse, from inhibition of sprouting of tubers and bulbs, to production of commercially sterile food products. At the same time, irradiation-induced chemical changes in food are minimal. Irradiation does not cause any significant loss of macronutrients. Proteins, fats and carbohydrates undergo minimal modifications in nutritional value, which are less significant compared with traditional methods of food preservation. Irradiation offers a potential to enhance microbiological safety and quality of food through extension of its shelf life. The aim of this review paper is to give an overview of the effects of ionizing radiation on microbial contaminants and nutritional characteristics of food. In the paper, the basic concepts of food irradiation, mode of action on microbes and the effects of ionizing radiation on nutritional quality of irradiated food are summarized.

Systematic Analysis Reveals Thermal Separations Are Not Necessarily Most Energy Intensive

Summary At the industrial level, separation of a variety of mixtures is predominantly carried out by thermally driven processes such as distillation. Nevertheless, the current literature seems to suggest that much is to be gained by replacing these processes with alternative non-thermal methods, which will potentially require a fraction of the energy used by distillation. This is primarily due to the widespread perception that thermal separation processes, particularly those that involve vaporization, are highly energy intensive. However, this belief is not well founded, because it is based on extrapolation from comparisons in the literature, many of which make ad-hoc assumptions and result in incorrect conclusions. Our analysis shows that this confusion arises because the processes utilize different types of energy: heat and electricity. Here, we present a consistent framework that enables a fair comparison between different processes that consume different forms of energies. Using this framework, we refute the general perception that thermal separation processes are inherently the most energy intensive and conclusively show through the examples of two challenging mixtures constituting components with low relative volatilities, that distillation processes, when run properly, can consume remarkably lower fuel than non-thermal membrane alternatives, which have often been touted as more energy efficient.

Bacterial spore inactivation by non-thermal technologies: resistance and inactivation mechanisms

Thermal processing remains the major technology in food industry while it inevitably destructs sensory, nutrition and functional ingredients of food. In recent years, there has been a growing interest in non-thermal process. Spores are the dormant state of vegetative cells and have unique multilayers structure. A lot of research focused on the inactivation of spores due to its extremely resistance. This review focused on the inactivation effects and mechanisms of spores by non-thermal processing. High-pressure processing inactivated spores by two step pathways. First moderate high pressure induced the germination of spores, and the resistance decreased rapidly. Then the germinated spores inactivated as followed. Some non-thermal techniques such as ultrasound and ultraviolet radiation had synergistic effects and were usually applied as hurdle technologies.

Observation of the femtosecond laser-induced ultrafast amorphization in Ge2Sb2Te5 films by dynamics spectrum

We demonstrate ultrafast amorphization in a Ge2Sb2Te5 (GST) film through a nonthermal process by femtosecond pump-probe experiments. A strong absorption peak in 532 nm is founded during the amorphization and the energy level corresponded is about 0.65~3.82 eV by calculations. First-Principles Calculations simulation experiments are used to prove the results of experiment and then explain the mechanism of amorphization of GST. Also, results of experiments show that the time to reach the absorption peak is decided by pulse width and wavelength but not the laser influence.

A techno-economic evaluation for the genipin recovery from Genipa americana L. employing non-thermal and thermal high-intensity ultrasound treatments

This paper presents techno-economic results for the high-intensity ultrasound (HIUS)-assisted extraction of a valuable phytochemical. Genipin is a precussor of natural blue compounds besides presenting anticancer, anti-oxidative, and anti-inflammatory properties. The effects of the non-thermal and thermal HIUS treatments on obtaining of genipin-rich ethanolic extracts from the unripe Genipa americana L. were evaluated. The HIUS treatments were evaluated in the economic viewpoint to show their feasibility in different scenarios. The non-thermal HIUS-assisted extraction, with a maximum temperature of 30 ± 1 °C, was performed applying a nominal power of 100 W and the thermal extraction with 450 W, achieving a maximum temperature of 73 ± 1 °C. For both treatments, the HIUS specific energy levels of 1, 3, and 5 kJ/g were assessed. The unripe genipap extracts obtained were characterized during their storage time (0, 24, 48, and 72 h) at 24 ± 2 °C according to their genipin and geniposide content and visual appearance. The cost of manufacturing was evaluated in a pilot and industrial-scale for the different HIUS treatments studied. Our results demonstrated that the HIUS-assisted extractions allowed us to obtain different amounts of genipin and geniposide according to the non-thermal and thermal process conditions. The more intense acoustic cavitation provided by the nominal power of 450 W resulted in a better diffusion and, consequently, higher genipin recovery. The economic evaluation showed different scenarios to produce genipin-rich ethanolic extracts by HIUS technology. In comparison with a process using pressing + low-pressure extraction, our HIUS processes presented a faster and fixed capital investment two times cheaper.

Performance evaluation of a new mobile air-treatment technology at-rest and under normal work conditions in a conventional hematology room

Invasive fungal infections incidence in patients with hematological malignancies is increasing. Air treatment remains an essential preventive measure. Guidelines state that high-risk patients should be housed in units equipped with High-Efficiency Particulate Air filtration. Mobile air-treatment devices may be considered as alternatives or as a complement to the ventilation system. We assessed the decontamination performances of a new mobile air-treatment device in a conventional hematology room. This device connected or not to a plenum combining Ultra-Low Particulate Air filtration and non-thermal catalysis process has been evaluated with or without healthcare activities (one sampling at-rest and triplicate samplings in activity). Environmental particulate, airborne and surface fungal and total mesophilic flora (TMF) samplings were performed with a total of 1800 min of particles counting, 144 air and 240 surface samplings. At-rest, both devices achieved a 2-log decrease of airborne particles, ISO 4 being the maximal particle class reached under the plenum. Whatever the healthcare activities and the location in the room, ISO 7 was the maximal particle class reached. TMF and fungal air contamination were lower during healthcare activities when the air portable cleaners were running. The bed was the area the least contaminated in the room. No differences were observed for surface contamination. This work provides arguments of the efficacy of a new mobile air-treatment device to decrease particle counts and airborne bioburden in real-life conditions. Studies have yet to be conducted to document the impact of these devices on the risk of invasive aspergillosis in immunocompromised patients.

Effect of moderate hydrostatic pressures on the enzymatic activity and bioactive composition of pineapple by‐products

AbstractThe application of abiotic stresses by moderate hydrostatic pressures (MHP) is still underdeveloped. Abiotic stresses allow activating the enzymatic complexes inducing the synthesis of de novo bioactive compounds. Pineapple by‐products are rich in bromelain and bioactive compounds that can be enhanced through abiotic stresses. The aim of this study was to evaluate the effect of MHP on the enzymatic activity of pineapple by‐products. Pineapple by‐products were submitted to MHP (50–400 MPa between 1 and 15 min) according to a central composite factorial design matrix. Samples were stored at 5 ± 1°C for 24 hr, to allow enzymatic activity to occur. Enzymatic and antioxidant activities and total phenolic compounds (TPC) were quantified. MHP promoted a 262% increase in the phenylalanine ammonia‐lyase activity and 36% increase in TPC, in shell samples. In core the activity of bromelain increased 350%. These results pinpoint the potential to increase the value of pineapple by‐products by enhancing the amounts of bioactive compounds through MHP application.Practical applicationAbiotic stresses can enhance enzyme activity, inducing the synthesis of bioactive compounds in living tissues. Hydrostatic pressure is an innovative nonthermal process that can be used to stabilize or increase enzymes' activity present in by‐products generated in the minimally processed fruit and vegetables industry. Moderate hydrostatic pressure (MHP) act as abiotic stress inducing de novo phenols synthesis and enhancing bromelain activity. After treatment, enriched material could be stabilized and then blended with foods and beverages to improve nutraceutical properties and help in the prevention and treatment of chronic diseases. The study demonstrates that MHP (150–250 MPa) applied to the pineapple core and pineapple shell produce a phenolic and bromelain rich product.

Purification of organic pollutants in cationic thiazine and azo dye solutions using plasma-based advanced oxidation process via submerged multi-hole dielectric barrier discharge

Due to industrialization and population growth, water shortage has emerged as a critical global issue. Pollution of existing water supplies is a critical part of this issue, and organic contaminants are one of the main causes of water pollution. The non-thermal plasma-based advanced oxidation process (AOP) is one of the most widely studied and best developed processes owing to its simple structure and ease of operation. In this study, a plasma-based AOP was stably generated using submerged multi-hole dielectric barrier discharge (DBD) and added to an aqueous solution. Using a plasma system, the complexity of the process for generating hydroxyl radicals (OH) can be simplified by allowing ozone, hydrogen peroxide, ultraviolet light (UV), and OH to be generated simultaneously in one device. The electrical properties and concentrations of the active species were analyzed to establish optimal plasma operating conditions. Among the organic pollutants, methylene blue (MB) and methyl orange (MO) were selected as experimental targets because they are representative cationic thiazine and azo dyes, respectively. The results were analyzed by measuring the absorbance of UV–Vis, total organic carbon (TOC), chromaticity, and changes in solution properties. The effects of hydroxyl radical (OH) scavengers (D-mannitol) on the MB and MO degradation rates were also investigated. Based on these results, degradation mechanisms of MB and MO are proposed. After 3 min of plasma treatment, the concentration, chromaticity, and TOC of MB and MO rapidly decreased. Consequently, we believe that plasma-based AOP using submerged multi-hole DBD has advantages as an alternative technology for treating organic pollutants.

A Sand-Arch Stability Constrained Dynamic Fractal Wormhole Growth Model for Simulating Cold Heavy-Oil Production with Sand

Summary Cold heavy-oil production with sand (CHOPS) is a nonthermal primary process that is widely adopted in many weakly consolidated heavy-oil deposits around the world. However, only 5 to 15% of the initial oil in place is typically recovered. Several solvent-assisted schemes are proposed as follow-up strategies to increase the recovery factor in post-CHOPS operations. The development of complex, heterogeneous, high-permeability channels or wormholes during CHOPS renders the analysis and scalability of these processes challenging. One of the key issues is how to properly estimate the dynamic growth of wormholes during CHOPS. Existing growth models generally offer a simplified representation of the wormhole network, which, in many cases, is denoted as an extended wellbore. Despite it being commonly acknowledged that wormhole growth due to sand-arch failure is likely to follow fractal statistics, there are no established workflows to incorporate sand-arch stability constraints into the construction of these fractal wormhole patterns. A novel dynamic wormhole growth model is developed to generate a set of realistic fractal wormhole networks during the CHOPS operations. It offers an improvement to the diffusion limited aggregation (DLA) algorithm with a sand-arch stability criterion. The outcome is a fractal pattern that mimics a realistic wormhole growth path, with sand-arch failure and fluidization being controlled by sand-arch stability constraints. The fractal pattern is updated dynamically by coupling compositional flow simulation on a locally refined grid and a stability criterion for the sand arch: the wormhole would continue expanding following the fractal pattern, provided that the pressure gradient at the tip exceeds the limit corresponding to a sand-arch stability criterion. Important transport mechanisms including foamy oil (nonequilibrium exsolution of gas) and sand-arch failure are integrated. Public field data for several CHOPS fields in Canada are used to examine the results of the dynamic wormhole growth model and flow simulations. For example, the sand production history is used to estimate a practical range for the critical pressure gradient representative of the sand-arch stability criterion. The oil and sand production histories show good agreement with the modeling results. In many CHOPS or post-CHOPS modeling studies, constant wormhole intensity is commonly assigned uniformly throughout the entire domain; as a result, the ensuing models are unlikely to capture the complex heterogeneous distribution of wormholes encountered in realistic reservoir settings. This work, however, proposes a novel model to integrate a set of statistical fractal patterns. The entire workflow has been readily integrated with commercial reservoir simulators, enabling it to be incorporated in practical field-scale operations design.

Effects of high hydrostatic pressure on the rheological properties and foams/emulsions stability of Alyssum homolocarpum seed gum.

The ability to modify food and increase the shelf life by enhanced stability using nonthermal process is of interest to many food companies. Here, we investigate the effects of high hydrostatic pressure (HHP), as a nonthermal process, at various pressure levels (200, 400, and 600 MPa for 30 min) on the functional properties of aqueous dispersions of Alyssum homolocarpum seed gum (AHSG). In this regard, the rheological properties, foam stability, and emulsion stability of the HHP‐treated gums were analyzed and compared. Dynamic oscillatory test indicated that the HHP‐treated gums had more gel‐like behavior than viscous‐like behavior (storage modulus > loss modulus) at designated pressures. When AHSG was treated by HHP, both elastic (G′) and viscous (G″) moduli were increased compared to the native AHSG. The native‐ and HHP‐treated gums exhibited a shear‐thinning (pseudoplastic) behavior. Furthermore, the pressure levels have a significant effect on consistency coefficient, flow behavior index, and yield stress (p < .05) of AHSG. The results showed that the HHP‐treated gums lead to improve the foam and emulsion stability of AHSG. Finally, we assume that HHP‐treated AHSG improves texture in the food materials.

Repetitive non-thermal melting as a timing monitor for femtosecond pump/probe X-ray experiments

Time-resolved optical pump/X-ray probe experiments are often used to study structural dynamics. To ensure high temporal resolution, it is necessary to monitor the timing between the X-ray pulses and the laser pulses. The transition from a crystalline solid material to a disordered state in a non-thermal melting process can be used as a reliable timing monitor. We have performed a study of the non-thermal melting of InSb in single-shot mode, where we varied the sample temperature in order to determine the conditions required for repetitive melting. We show how experimental conditions affect the feasibility of such a timing tool.

Quality Characteristics and Clinical Relevance of In-House 3D-Printed Customized Polyetheretherketone (PEEK) Implants for Craniofacial Reconstruction.

Additive manufacturing (AM) of patient-specific implants (PSIs) is gradually moving towards in-house or point-of-care (POC) manufacturing. Polyetheretherketone (PEEK) has been used in cranioplasty cases as a reliable alternative to other alloplastic materials. As only a few fused filament fabrication (FFF) printers are suitable for in-house manufacturing, the quality characteristics of the implants fabricated by FFF technology are still under investigated. This paper aimed to investigate PEEK PSIs fabricated in-house for craniofacial reconstruction, discussing the key challenges during the FFF printing process. Two exemplary cases of class III (Group 1) and class IV (Group 2) craniofacial defects were selected for the fabrication of PEEK PSIs. Taguchi’s L9 orthogonal array was selected for the following nonthermal printing process parameters, i.e., layer thickness, infill rate, number of shells, and infill pattern, and an assessment of the dimensional accuracy of the fabricated implants was made. The root mean square (RMS) values revealed higher deviations in Group 1 PSIs (0.790 mm) compared to Group 2 PSIs (0.241 mm). Horizontal lines, or the characteristic FFF stair-stepping effect, were more perceptible across the surface of Group 1 PSIs. Although Group 2 PSIs revealed no discoloration, Group 1 PSIs displayed different zones of crystallinity. These results suggest that the dimensional accuracy of PSIs were within the clinically acceptable range; however, attention must be paid towards a requirement of optimum thermal management during the printing process to fabricate implants of uniform crystallinity.

Paracetamol Degradation by Catalyst Enhanced Non-Thermal Plasma Process for a Drastic Increase in the Mineralization Rate

In order to remediate the very poor mineralization of paracetamol in water, even when well degraded by using a Non-Thermal Plasma (NTP) process at a very low dissipated power, a plasma-catalyst coupling process was tested and investigated. A homemade glass fiber supported Fe3+ catalyst was immersed in the liquid to be treated in a Dielectric Barrier Discharge plasma reactor. The plasma-catalysis process, at the same low dissipated power, achieved a mineralization rate of 54% with a full conversion rate of paracetamol at 25 mg L−1 in initial concentration after 60 min treatment, thanks to Fenton-like effects. The synergetic effects of the plasma-catalysis coupling process also improved the Energy Yield by a factor of two. The catalyst before and after use for treatment was characterized by Brunauer-Emmett-Teller and Thermogravimetric analysis. High-Performance Liquid Chromatography was used to measure the concentration of treated solution and to investigate the intermediates. Two of them, namely 1,4-hydroquinone and 1,4-benzoquinone, were formally identified. Some intermediates are presented in this paper as a function of treatment time and their UV absorbance spectra. NTP processes with and without catalyst coupling were compared in terms of acidity, conductivity, and nitrate concentrations in the treated solution.

Degradation of Acid Orange 7 Azo Dye in Aqueous Solution by a Catalytic-Assisted, Non-Thermal Plasma Process

The aim of this work was the optimization of the performance of the cold plasma technology coupled with a structured catalyst for the discoloration and mineralization of “acid orange 7” (AO7) azo dye. The structured catalyst consists of Fe2O3 immobilized on glass spheres, and it was prepared by the “dip coating” method and characterized by different chemico-physical techniques. The experiments were carried out in a dielectric barrier discharge (DBD) reactor. Thanks to the presence of the catalytic packed material, the complete discoloration and mineralization of the dye was achieved with voltage equal to 12 kV, lower than those generally used with this technology (approximately 20–40 kV). The best result in terms of discoloration and mineralization (80% after only 5 min both for discoloration and mineralization) was obtained with 0.25 wt% of Fe2O3 immobilized on the glass spheres, without formation of reaction by-products, as shown by the HPLC analysis. The optimized catalyst was reused for several reuse cycles without any substantial decrease of performances. Moreover, tests with radical scavengers evidenced that the most responsible oxidizing species for the degradation of AO7 dye was O2•−.

Reduction of Inrush Current in a Shockwave Non-Thermal Food Processing System Using an Exponential Clock Pulse Generator

Recently, shockwave food processing is drawing much attention as a low-cost non-thermal food process technique. In shockwave non-thermal food processing, underwater shockwaves are generated by a high voltage generator. Therefore, high inrush currents and high voltage stress on circuit components significantly reduce the reliability and life expectancy of the circuit. However, to the best of our knowledge, stress reduction techniques and their experimental verification have not been studied yet in the shockwave non-thermal food processing system. In this paper, we propose a stress reduction technique for the shockwave non-thermal food processing system and investigate the effectiveness of the proposed technique experimentally. To achieve high reliability and life expectancy, a new high voltage multiplier with an exponential clock pulse generator is proposed for the shockwave non-thermal food processing system. By slowing down the rate at which the capacitors charge in the high voltage multiplier, the exponential clock pulse generator significantly reduces the inrush current. Furthermore, to perform shockwave non-thermal food processing continuously at a lower voltage level, we present a new electrode with a reset mechanism for wire electric discharge (WED), where a square-shaped metal wire swings on a hinge in the proposed electrode. The proposed electrode enables not only shockwave generation at a lower voltage level but also continuous non-thermal food processing, because the square-shaped metal wire is not melted in the WED process. To confirm the validity of the proposed techniques, some experiments are performed regarding the laboratory prototype of the shockwave non-thermal food processing system. In the performed experiments, reduction of inrush currents and effective food processing are confirmed.

Inactivation of Salmonella on black peppercorns using an integrated ultraviolet-C and cold plasma intervention

A nonthermal process that applies ultraviolet (UV)–C and helium cold plasma (CP) simultaneously (UV-CP) has been investigated as an intervention technology to inactivate Salmonella on black peppercorns. The optimum CP treatment voltage and UV-CP treatment time for inactivating Salmonella on black peppercorns were predicted using a model equation as 9.7 kV and 22.1 min, respectively, which non-thermally inactivated Salmonella by 3.7 log CFU/g. UV-CP treatment yielded a stronger bactericidal activity than UV treatment alone, without inducing photoreactivation. In addition, UV-CP-induced reactive species were similar to those found in individual UV and CP treatments. Furthermore, UV-CP treatment caused a profound deformation of Salmonella morphology and a greater extent of DNA damage than UV or CP treatment did alone. UV-CP treatment did not alter the color or 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity; however, it lowered the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and piperine concentration in the peppercorns. The findings of this study demonstrate the potential application of UV-CP treatment for decontamination of black peppercorns.

Recent progress on organosilicon coatings deposited on bleached unrefined Kraft paper by non-thermal plasma process at atmospheric pressure

In future years, recent progress in plasma processing using non-thermal plasmas at atmospheric pressure will be used to improve numerous natural by-product applications, including those based on materials derived from woody biomass. This work provides a detailed study of the morphological and chemical modification of bleached, unrefined Kraft paper obtained in homogeneous, plane-to-plane dielectric barrier discharges at atmospheric pressure in the presence of 2,4,6,8-tetramethylcyclotetrasiloxane (TMCTS) precursor. High-resolution SEM images highlight the presence of micro and nanoscale fibrous structures on the raw surface as well as their influence on the heterogeneous growth dynamics of the organosilicon film. Through FTIR and XPS analysis, it is further demonstrated that it is possible to take advantage of the natural porous structure of the cellulosic substrate to obtain both surface and volume treatment. Such analysis further revealed a low plasma-assisted fragmentation of the TMCTS precursor and a partial oxidation of the TMCTS precursor fragments during the plasma deposition process to form a Si-O-Si network. Over the range of experimental conditions investigated, wettability with water measurements reveal significant water repellency of the naturally hydrophilic cellulosic substrate. For sufficiently thick coatings, the plasma-processed materials remained unchanged even after 20 h of water immersion, a very promising result to reduce the degradation of ligno-cellulosic materials in humid and aggressive conditions.

Synthesis of carbon nanoparticles in a non-thermal plasma process

A non-thermal plasma source based on magnetically stabilized gliding arc discharge (MSGAD) was used to prepare carbon nanoparticles via methane decomposition. Spherical carbon nanoparticles (SCNs), few-layer graphene nanoflakes (GNFs), and nitrogen-doped carbon nanoparticles were obtained. The results showed that the product microstructure was influenced by the buffer gas. In pure methane and argon, the products were a mixture of SCNs and GNFs. In helium and hydrogen, all products were highly crystalline GNFs with low defects, few layers, large BET surface areas, and excellent thermal stability. Under a nitrogen atmosphere, nitrogen-doped nanoparticles were formed, and the products were a mixture of GNFs, disordered graphitic layers, and tiny spots similar to carbon dots. The formation of GNFs was possibly related to the high input power and abundant hydrogen atoms, while the complex product morphology obtained under a nitrogen atmosphere was likely caused by the incorporation of nitrogen atoms.

The impact of high power ultrasound for controlling spoilage by Alicyclobacillus acidoterrestris: A population and a single spore assessment

Consumer demand for healthier, microbiologically safe and stable, higher quality and minimally processed foods has increased in the last decades, promoting the application of non-thermal process technologies. Ultrasound processing is gaining attention because of its potential for improving quality and safety while retaining product flavor, texture, color and nutrient composition. Recently, Alicyclobacillus acidoterrestris has been recognized by manufacturers and processors in the fruit industry as a new type of thermoacidophilic, endospore-forming spoilage bacterium for commercialized fruit juices that can withstand the high temperatures applied in pasteurization process and spoil them producing taint compounds. Based on the above, the present study was undertaken to investigate the separate and combined effect of ultrasound treatment operating at 26 kHz, 90 μm, 200 W for 5, 10, 15 min and heat stress (at 80 °C for 10 min) on the recovery of A. acidoterrestris spores in K broth adjusted to pH = 4.5 with 25% (w/v) citric acid at temperatures between 35 and 45 °C at population and individual spore level. At the population level, statistically significant differences in average lag time of A. acidoterrestris spores from different treatments at 35 and 45 °C have been found. After the applied ultrasound (at 100% Amplitude for 10 min) and heat shock (at 80 °C for 10 min), the average lag time of A. acidoterrestris spores at 35 °C (7.24 ± 0.34 h) and 45 °C (6.38 ± 0.18 h) has been shown to be longer compared to the control at 35 °C (5.68 ± 0.36 h) and at 45 °C (2.87 ± 0.19 h), while for this combination, the maximum specific growth rate was not significantly different from the control samples. Additionally, the findings of this study have shown that λ among individual spores was greatly variable when they were treated by ultrasound (at 100% Amplitude for 10 min) and/or thermal treatment (at 80 °C for 10 min). The application of ultrasound and thermal treatment resulted in a more pronounced effect on median lag phase duration (25.74 h) than the heat shock (11.63 h) and affected both the position and the spread of the λ distributions of A. acidoterrestris spores. This work would help to better assess and optimize the proposed combined treatments, since ultrasound and thermal treatments could work in a synergistic way on delaying the lag time of the tested bacterial spores.