Effect Of High Pressure Processing Research Articles

Effects of High-Pressure Processing on the Biosynthesis of γ-Aminobutyric Acid in Cocoa Beans Fermented with Lactobacillus senmaizukei

Effects of High-Pressure Processing on the Biosynthesis of γ-Aminobutyric Acid in Cocoa Beans Fermented with Lactobacillus senmaizukei

High-pressure processing and heat treatment of Murrah buffalo milk: Comparative study on microbial changes during refrigerated storage

This study aims to evaluate the effect of high-pressure processing (HPP) (500 and 600 MPa for 3 min and 5 min) on the microbial changes of Murrah buffalo milk in comparison to heat treatment (72 °C for 15 s of holding time) during refrigerated storage of 28 days. The results indicated that the total plate count (TPC) of raw milk at day 0 was 5.5 ± 0.6 log10 CFU/mL. At day 0, heat treatment lowered TPC to 3.9 ± 0.6, while HPP treatment was in the range of 4.1 ± 0.3 to 4.8 ± 0.6 log10 CFU/mL. Similarly, lowered yeast and mold count and lactic acid bacteria were noted in heat- and HPP-treated milk samples compared to the control sample during refrigerated storage. There were no Staphylococcus aureus and Escherichia coli detected in heat and HPP-treated samples. Heat or HPP treatment at 600 MPa for 5 min significantly extended the shelf-life of Murrah buffalo milk for three weeks at the refrigerated storage. In addition, HPP treatment did not alter the pH, lightness (L* value), protein, or fat content of Murrah buffalo milk during refrigerated storage. Hence HPP at 600 MPa for 5 min could be a suitable alternative to conventional heat treatment.

Comparative Effects of HPP and Irradiation on Plant-Based Whole Hard-Boiled Eggs

This study compared the effects of high-pressure processing (HPP) and irradiation on the shelf life and quality of plant-based whole hard-boiled eggs. The objective was to determine the optimal treatment doses for microbial inactivation and shelf life, and to assess their impacts on the product's physical, chemical, and sensory properties. Irradiation treatments were applied at 0, 2, 3.5, and 5 kGy, while HPP was conducted at 0, 300, 400, and 500 MPa. Post-treatment analysis included assessments of physical, chemical, and microbial quality, focusing on Clostridium perfringens, and sensory evaluations using a 9-point hedonic scale. Shelf life was predicted using accelerated shelf-life testing (ASLT) at 40°C and 50°C, employing the temperature acceleration factor (Q10) and temperature quotient (Q1). Results showed that gamma irradiation at 3.5 kGy and electron beam irradiation at 5 kGy both provided a predicted shelf life of 217 days, while HPP at 500 MPa resulted in a predicted shelf life of 146 days. All treatments initially eliminated microorganisms effectively, but HPP showed potential for spore germination during extended storage. Sensory evaluations indicated that electron beam irradiation and HPP better maintained product quality compared to gamma irradiation at higher doses. This study provides valuable insights for food manufacturers seeking to enhance the safety and quality of plant-based egg alternatives using non-thermal processing methods.

Effect of High-Pressure Processing on the Antioxidant and Antibacterial Properties of Honey

AbstractHigh pressure processing (HPP) have the potential to be used as an alternative to commercial thermal processing of honey. Its impact on the antioxidant and antibacterial properties of honey have yet to be understood properly. This study focuses on the effects of HPP on the antioxidant and antibacterial properties of honey. Six different honey samples were subjected to HPP at 400 and 600 MPa for 10 and 15 min. The antioxidant properties were measured in terms of total phenolic content, total flavonoid content, the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging assay, and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) free radical scavenging assay. The antibacterial activity was measured as the minimum bacteriocidal and minimum bacterial inhibition concentration of honey against S. aureus, P. aeruginosa and E. coli. HPP decreased the total phenolic content and increased the total flavanoid content. There was an increase in the antibacterial activity of HPP honey against S. aureus, whereas no significant changes were observed against P. aeruginosa, and E. coli. It was evident that the changes in the antioxidant and antibacterial activity of honey samples were dependent on the HPP processing parameters and the type of honey.

Effect of high pressure processing on the structural and functional properties of the protein in corn gluten meal

ABSTRACT The presentation of high pressure processing (HPP) on corn starch has been reported, but the effect on protein in corn gluten meal (CGM) is rarely explored. The purposes of this study were to investigate the effect of HPP treatment on structural and functional properties of the protein in CGM. Protein was treated at 200–600 MPa for 5–15 min. Results showed that HPP treatment increased protein solubility, water and oil binding capacities, emulsion stability, foaming and foam stability. Protein which treated at 400 MPa for 15 min had the more enhanced functionality. Moreover, under this condition, the protein aggregates gradually dissociated, and the particle size decreased. These results indicated that the functional groups and structure of CGM protein were affected by the HPP treatment. We hope to convert an underutilized material into a valuable one through HPP in food industry.

Effects of high pressure processing on structural changes, aggregation, and binding mechanisms of β-Lactoglobulin with typical polyphenols

The binding capacity of β-Lactoglobulin (BLG) is crucial for delivering polyphenols, influenced by structural changes. High pressure processing (HPP) has the potential to modify BLG's structure and aggregation, but its specific impact on BLG-polyphenol interactions is uncertain. This study used circular dichroism spectroscopy and molecular dynamics simulations to reveal HPP-induced structural changes in BLG, supported by particle size analysis indicating aggregation. Seven structurally diverse polyphenols (quercetin-QR, hesperetin-HSP, dihydromyricetin-DHM, gallic acid-GA, (−)-epicatechin-EC, resveratrol-RES, and secoisolariciresinol diglucoside-SDG) were investigated to comprehensively analyze their binding patterns using fluorescence spectroscopy and molecular docking. HPP reduced BLG's ordered structure and increased its aggregation. Binding affinities peaked at 400 MPa for DHM, QR, HSP, GA, and RES, while SDG and EC exhibited maximum affinities at atmospheric pressure and 600 MPa, respectively. Elevated pressures enhanced BLG-polyphenol interactions, particularly at residues 44GLU and 160CYS, with van der Waals forces dominating the binding free energy.

Combined effects of high pressure processing and sous-vide cooking on the tenderization of proteolytic enzyme-injected chicken breast

The combined effects of high pressure processing (HPP), sous-vide cooking (SV), and their processed sequence on papaya extract (PaExt) tenderized chicken breast were investigated. Chicken breasts were injected with 0.05% PaExt and then divided into HPP + SV or SV + HPP where the HPP conditions were 250 or 450 MPa for 10 min and meats were SV cooked at 61 °C for 100 min. The cooking loss, pH value, meat color, texture, and microstructure of treated chicken breasts were determined. PaExt treated chicken breast with HPP + SV had the lowest values in all texture parameters and the highest cooking loss among all treatments. Microstructural images further explained the tenderization of PaExt + HPP + SV treatments which caused severe degradation and denaturation of muscle fibers and connective tissues. Therefore, the application of PaExt + HPP + SV may lead to tender meat texture which is easier for the elderly to consume and also shows the potential of elderly care food development.

The Effect of High-Pressure Processing of Caprine Milk on the Production and Properties of Yoghurt.

The aim of this study was to determine the suitability of HP-treated caprine milk for yoghurt production and to evaluate the effect of HP treatment on yoghurt properties. Reconstituted caprine milk was subjected to HP treatment (350 MPa/10 min/20 °C); a lactic acid starter culture (YC-X16, Chr. Hansen) was added. Milk was fermented at a temperature of 43 °C until pH 4.60. Bacterial counts, pH, color, rheological characteristics, texture, microstructure, and the sensory attributes of the yoghurt were determined after production and after seven days of storage at a temperature of 4 °C. HP treatment increased color saturation and whiteness index and induced a minor increase in milk pH. Minor differences in the acidification curve were noted. During storage, Streptococcus thermophilus counts were significantly higher in yoghurt from HP-treated than from untreated milk, whereas Lactobacillus delbruecki ssp. bulgaricus counts remained stable. A color analysis did not reveal differences between the experimental and control yoghurts. After storage, yoghurt made from HP-treated milk was characterized by thicker consistency and lower rheological stability than the control yoghurt. The micrographs of the yoghurts confirmed the differences in rheological parameters. Yoghurt produced from HP-treated caprine milk and stored for seven days received the highest scores in the sensory evaluation.

High-Pressure Processing Effects on Microbiological Stability, Physicochemical Properties, and Volatile Profile of a Fruit Salad.

Nowadays, consumers are more aware of the effects of their diet on their health, and thus demand natural or minimally processed food products. Therefore, research has focused on processes that assure safe products without jeopardizing their nutritional properties. In this context, this work aimed to evaluate the effects of high-pressure processing (550 MPa/3 min/15 °C, HPP) on a fruit salad (composed of melon juice and pieces of Golden apple and Rocha pear) throughout 35 days of storage at 4 °C. For the physicochemical properties analysed (browning degree, polyphenol oxidase activity, antioxidant activity (ABTS assay), and volatile profile), a freshly made fruit salad was used, while for the microbiological tests (total aerobic mesophiles, and yeast and moulds) spoiled melon juice was added to the fruit salad to increase the microbial load and mimic a challenge test with a high initial microbial load. It was determined that processed samples were more microbiologically stable than raw samples, as HPP enabled a reduction of almost 4-log units of both total aerobic mesophiles and yeasts and moulds, as well as an almost 1.5-fold increase in titratable acidity of the unprocessed samples compared to HPP samples. Regarding browning degree, a significant increase (p < 0.05) was observed in processed versus unprocessed samples (roughly/maximum 68%), while the addition of ascorbic acid decreased the browning of the samples by 29%. For antioxidant activity, there were no significant differences between raw and processed samples during the 35 days of storage. An increase in the activity of polyphenol oxidase immediately after processing (about 150%) was confirmed, which was generally similar or higher during storage compared with the raw samples. Regarding the volatile profile of the product, it was seen that the compounds associated with melon represented the biggest relative percentage and processed samples revealed a decrease in the relative quantity of these compounds compared to unprocessed. Broadly speaking, HPP was shown to be efficient in maintaining the stability and overall quality of the product while assuring microbial safety (by inactivating purposely inoculated microorganisms), which allows for longer shelf life (7 versus 28 days for unprocessed and processed fruit salad, respectively).

Influence of High-Pressure Processing and Microbial Transglutaminase on the Properties of Pea Protein Isolates

This study investigated the effects of high-pressure processing (HPP; 600 MPa/15 min) and microbial transglutaminase-catalyzed (MTG; 30 U·g of protein−1) crosslinking on the concentration of dissolved proteins (SOL), free sulfhydryl groups (SH), surface hydrophobicity (H0), and viscosity of pea protein isolates (PPI) at different concentrations (1–13%; w/v). The SOL increased by increasing protein concentration (max. 29%). MTG slightly affected SOL. HPP decreased SOL with increasing protein concentration, and the combination MTG + HPP resulted in a lower SOL than HPP alone. The concentration of SH in untreated PPI increased with increasing protein concentration, reaching a maximum of 8.3 μmol·mg prot−1. MTG increased SH at higher protein concentrations. HPP lowered SH, but its concentration increased by increasing protein concentration. HPP + MTG offset the effect of MTG, yielding lower SH. MTG did not affect H0 at 1% concentration but increased it for concentrations from 3–5%, and there was a decrease with 7–9%. HPP increased H0 up to 37% for intermediate protein concentrations but did not affect it at higher concentrations. MTG + HPP decreased H0 at all protein concentrations. The viscosity of the dispersions increased with protein concentration. HPP increased the viscosity of the dispersions for concentrations above 7%, while MTG only caused changes above 9%. Combined MTG + HPP resulted in viscosity increase. The results underscore the opportunity for innovative development of high-protein products with improved properties or textures for industrial application.

The High Pressure Preservation of Honey: A Comparative Study on Quality Changes during Storage.

In commercially available honey, the application of a heat treatment to prevent spoilage can potentially compromise its beneficial properties and quality, and these effects worsen with extended storage. The high-pressure processing (HPP) of honey is being explored, but its long-term impact on honey quality has not been characterised yet. This study evaluated the effects of HPP and thermal processing on the microbial load, physicochemical quality (i.e., hydroxymethylfurfural content and diastase activity), and antioxidant capacity of honey after treatment and following extended storage (6, 12, and 24 months) at 20 °C. Pasteurization (78 °C/6 min) effectively eliminated the microorganisms in honey but compromised its physicochemical quality and antioxidant activity. HPP initially showed sublethal inactivation, but storage accelerated the decrease in yeasts/moulds and aerobic mesophiles in honey (being <1 log CFU/g after 24 months of storage) compared to unprocessed honey and honey thermally treated under mild conditions (55 °C/15 min). The physicochemical characteristics of the quality of HPP-treated honey and raw unprocessed honey did change after long-term storage (24 months) but remained within regulatory standards. In conclusion, HPP emerged as a more suitable and safe preservation method for Apis mellifera honey, with a minimal risk of a loss of antioxidant activity compared to traditional industrial honey pasteurization.

High-Pressure Processing of Fruit Smoothies Enriched with Dietary Fiber from Carrot Discards: Effects on the Contents and Bioaccessibilities of Carotenoids and Vitamin E.

The effects of high-pressure processing (HPP) (450 MPa/600 MPa/3 min) on the carotenoid and vitamin E contents of smoothies made from strawberry, orange juice, banana and apple, and the same smoothies enriched with dietary fiber from discarded carrots were compared. The contents and bioaccessibilities of these compounds were also evaluated over the course of 28 days at 4 °C. The application of HPP in the formulations significantly increased the contents of β-cryptoxanthin, α-carotene and β-carotene and retained the contents of lutein, zeaxanthin and vitamin E compared to untreated samples. A decreasing trend in the content of each compound was observed with an increase in storage time. The application of HPP initially led to reductions in the bioaccessibility of individual compounds. However, overall, during storage, there was an increase in bioaccessibility. This suggests that HPP influences cell structure, favoring compound release and micelle formation. HPP is a sustainable method that preserves or enhances carotenoid extractability in ready-to-drink fruit beverages. Furthermore, the incorporation of dietary fiber from carrot processing discards supports circular economy practices and enhances the health potential of the product.

Impact of High Pressure Processing on the Safety and Quality of Food Products: A Review.

High pressure processing (HPP) has become a practical food processing technique that meets the preferences of consumers seeking lightly processed, convenient, and fresh-tasting food options. This paper reviewed the latest research on the impact HPP on the safety and quality of food products. The use of HPP has been showing favorable growth in the food industry primarily due to its potential to not only enhance the nutritional content and sensory attributes of food products but also to substantially extend their shelf-life and bolster safety standards. HPP is the most used among non-thermal food processing technologies. While its direct application to milk for consumption falls short of delivering consistent quality, it proves effective as a pretreatment step and in products using milk as a primary ingredient. In the context of meat production, HPP reduces microbial loads and extends shelf-life, yet concerns persist regarding its impact on product quality. The absence of in-depth studies regarding the attributes of carrots that support pathogen regeneration emphasizes the need for comprehensive research in this area, which could have far-reaching implications for similar fruit and vegetable products. This review underscores the need for a balanced assessment of HPP's effects on food safety and quality, offering insights that can guide the food industry in adopting this technology while ensuring consumer satisfaction and safety.

Inactivation mechanisms on pectin methylesterase by high pressure processing combined with its recombinant inhibitor

High pressure processing (HPP) juice often experiences cloud loss during storage, caused by the activity of pectin methylesterase (PME). The combination of HPP with natural pectin methylesterase inhibitor (PMEI) could improve juice stability. However, extracting natural PMEI is challenging. Gene recombination technology offers a solution by efficiently expressing recombinant PMEI from Escherichia coli and Pichia pastoris. Experimental and molecular dynamics simulation were conducted to investigate changes in activity, structure, and interaction of PME and recombinant PMEI during HPP. The results showed PME retained high residual activity, while PMEI demonstrated superior pressure resistance. Under HPP, PMEI's structure remained stable, while the N-terminus of PME's α-helix became unstable. Additionally, the helix at the junction with the PME/PMEI complex changed, thereby affecting its binding. Furthermore, PMEI competed with pectin for active sites on PME, elucidating. The potential mechanism of PME inactivation through the synergistic effects of HPP and PMEI.

The effect of high-pressure processing on quality of seafood meat- a review

High-pressure (HP) technology is useful for preserving food. When it applied to fish and shellfish, high-pressure (HP) treatment could result in several kinds of benefits since it would affect the extension of the shelf life of this extremely perishable seafood product. In contrast, under extreme conditions, changes in the meat's appearance, texture, and chemical composition can be observed in fish. The most significant modifications took place between 200 and 300 MPa, causing proteins to either partially or completely denature. These changes in turn affected the pH, hardness, whitening, water-holding capacity, the beginning of lipid and protein oxidation, and an increase in hardness. The brief overview of HP technology and its main impact on fish meat quality were reviewed in this paper by considering the targeted constituents and underlying mechanisms.

High-pressure processing enhances saltiness perception and sensory acceptability of raw but not of cooked cured pork loins-leveraging salty and umami taste.

The salt (NaCl) content in processed meats must be reduced because of its adverse effects on cardiovascular health. However, reducing salt in meat products typically leads to a lower taste intensity and, thus, consumer acceptability. Industry interventions must reduce salt content while maintaining taste, quality, and consumer acceptability. In this context, high-pressure processing (HPP) has been proposed to enhance saltiness perception, though there are contradictory reports to date. The present work aimed to conduct a targeted experiment to ascertain the influence of HPP (300/600 MPa) and cooking (71°C) on saltiness perception and sensory acceptability of meat products. HPP treatment (300/600 MPa) did enhance those two sensory attributes (approx. +1 on a 9-point hedonic scale) in raw (uncooked) cured pork loins but did not in their cooked counterparts. Further, the partition coefficient of sodium (PNa+), as an estimate of Na+ binding strength to the meat matrix, and the content of umami-taste nucleotides were investigated as potential causes. No effect of cooking (71°C) and HPP (300/600 MPa) could be observed on the PNa+ at equilibrium. However, HPP treatment at 300 MPa increased the inosine-5'-monophosphate (IMP) content in raw cured pork loins. Finally, hypothetical HPP effects on taste-mediating molecular mechanisms are outlined and discussed in light of boosting the sensory perception of raw meat products as a strategy to achieve effective salt reductions while keeping consumer acceptability.

Exploring the effects of high pressure processing on the quality of craft beer at an industrial scale

This study evaluated the potential of High Pressure Processing (HPP) to improve the quality and shelf-life of beer in 20-L PET kegs. India Pale Ale (IPA) and Blonde Ale alcohol-free (AF) beers were either processed at 600 MPa for 3 min or kept unprocessed. Physicochemical parameters such as pH, color, bitterness, haze, and ethanol content were monitored over 90 days of storage at 4 °C or room temperature. Microbiological spoilage indicators including total aerobic bacteria, yeasts and molds, and lactic acid bacteria were evaluated. Analysis revealed minimal changes in the physical characteristics of both beers following HPP. Additionally, no significant differences in bitterness, color, haze, density, or extract between HPP and untreated samples were detected. Microbiological spoilage indicators were reduced to below the quantification level (<25 CFU/ml). The results from similarity and preference tests indicated that HPP did not result in any notable variation of the sensory characteristics. This suggests that HPP can maintain the original flavor of beer while increasing its shelf-life during storage by inactivating microorganisms without adverse effects on key product attributes. The results of this study will be beneficial to industry professionals interested in understanding the benefits of HPP in beer production process.

Structural, physicochemical and functional properties of high-pressure modified white finger millet starch

The effect of high-pressure processing (HPP) modification (200, 400, and 600 MPa for 10 min) on the physico-chemical, functional, structural, and rheological properties of white finger millet starch (WFMS) was studied. Measured amylose content, water, and oil absorption capacity, alkaline water retention, and pasting temperature increased significantly with the intensity of pressure. All color parameters (L, a, b values, and ΔC) were affected by HPP treatment, and paste clarity of modified starch decreased significantly with an increase in storage time. The samples' least gelation concentration (LGC) is in the range of 8–14 %. An increasing solubility and swelling power are noted, further intensifying at the elevated temperature (90 °C). The structural changes of WFMS were characterized by XRD, SEM, and FTIR spectroscopy. Starch modified at 600 MPa showed a similar pattern as ‘B’-type crystalline, and the surfaces of starch deformed because of the gelatinization. Applied pressure of 600 MPa affected the FTIR characteristic bands at 3330, 2358, and 997 cm−1, indicating a lower crystallinity of the HPP-600 modified sample. According to DSC analysis, even at 600 MPa, WFMS is only partially gelatinized. This work provides insights for producing modified WFM starches by a novel physical modification method.

Combined antimicrobial effect of high pressure processing and ethyl lauroyl arginate (LAE)-containing films and its application in coconut water preservation

Combined antimicrobial effect of high pressure processing and ethyl lauroyl arginate (LAE)-containing films and its application in coconut water preservation

Effects of high-pressure processing of date palm juice on the physicochemical properties

Effects of high-pressure processing of date palm juice on the physicochemical properties