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Microbial instability is a common problem during bio-production based on microbial hosts. Halomonas bluephagenesis has been developed as a chassis for next generation industrial biotechnology (NGIB) under open and unsterile conditions. However, the hidden genomic information and peculiar metabolism have significantly hampered its deep exploitation for cell-factory engineering. Based on the freshly completed genome sequence of H. bluephagenesis TD01, which reveals 1889 biological process-associated genes grouped into 84 GO-slim terms. An enzyme constrained genome-scale metabolic model Halo-ecGEM was constructed, which showed strong ability to simulate fed-batch fermentations. A visible salt-stress responsive landscape was achieved by combining GO-slim term enrichment and CVT-based omics profiling, demonstrating that cells deploy most of the protein resources by force to support the essential activity of translation and protein metabolism when exposed to salt stress. Under the guidance of Halo-ecGEM, eight transposases were deleted, leading to a significantly enhanced stability for its growth and bioproduction of various polyhydroxyalkanoates (PHA) including 3-hydroxybutyrate (3HB) homopolymer PHB, 3HB and 3-hydroxyvalerate (3HV) copolymer PHBV, as well as 3HB and 4-hydroxyvalerate (4HB) copolymer P34HB. This study sheds new light on the metabolic characteristics and stress-response landscape of H. bluephagenesis , achieving for the first time to construct a long-term growth stable chassis for industrial applications. For the first time, it was demonstrated that genome encoded transposons are the reason for microbial instability during growth in flasks and fermentors. [Display omitted] • 84 GO-slim terms were classified to study the stress response of Halomonas. • A translation-dependent stress regulation pattern of Halomonas was uncovered. • Halo-ecGEM was developed for fermentation simulation with good fit. • A growth stable chassis WZY278ΔTns was developed aftter 8 transposases deletion. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Freshly extracted sugarcane juice is an ideal substrate for microbial fermentation and browning reactions. The present study is the first report on the potential of pulsed light (PL) processing in improving microbial stability with the retention of major bioactive. PL processing at different levels of voltage (2.1–2.7 kV) and number of pulses (100–200) was explored. The present study aimed to investigate the impact of PL processing on the quality of sugarcane juice, bioactive composition and microbial load.The microbial load, such as aerobic mesophiles, yeast and mold, and total coliform, was reduced to below 1 log colony‐forming units mL−1 in juice samples subjected to intense PL treatment at 2.7 kV. The maximum value of the total color difference of the sugarcane juice was below 4.0, even at extreme levels of PL process parameters. In comparison with the unprocessed juice, the reduction in total phenols (Folin ciocalteu reagent assay) and the total antioxidant capacity (2,2‐diphenyl‐1‐picrylhydrazyl free radical scavenging assay) was limited to 6% and 16.7%, respectively, when treated at 2.7 kV/200 pulses. The pH and total soluble solids of the juice remained unaffected in all the processed samples. Among the process parameters considered, the treatment voltage was found to significantly affect the quality parameters and microbial load.PL processing at 2.1 kV/170 pulses gave an optimally processed juice with a microbial load below the permissible limit and desirability value of 0.77. The results suggest that the PL treatment is effective for enhancing the microbial stability and maintaining the bioactive components of the sugarcane juice. Furthermore, the outcomes from the present study are expected to pave the way for further in‐depth investigation of the effect of PL treatment on the critical quality attributes and shelf life of sugarcane juice. The technology will be useful for adoption by different stakeholders, including manufacturers and retailers in the food processing sector. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

ABSTRACTThe aim of the current study was to explore the preservative effect of aqueous coriander extract and butylated hydroxytoluene (BHT) on the shelf life of refrigerated chicken patties for 9 days. For this purpose, BHT (100 ppm) and aqueous coriander extract (1%) was applied to improve the storage stability. The patties were evaluated for their physiochemical characterization including total phenolic content (TPC), thiobarbituric acid reactive substances (TBARS), peroxide value (PV), total carbonyl, metmyoglobin, and instrumental color, microbial analysis including (total plate count), and sensory attributes including (color and odor). The results showed that coriander extract has a significant (P

Linkages between microbial communities and multiple ecosystem functions are context-dependent. However, the impacts of different restoration measures on microbial communities and ecosystem functioning remain unclear. Here, a 14-year long-term experiment was conducted using three restoration modes: planting mixed grasses (MG), planting shrub with Salix cupularis alone (SA), and planting shrub with Salix cupularis plus planting mixed grasses (SG), with an extremely degraded grassland serving as the control (CK). Our objective was to investigate how ecosystem multifunctionality and microbial communities (diversity, composition, and co-occurrence networks) respond to different restoration modes. Our results indicated that most of individual functions (i.e., soil nutrient contents, enzyme activities, and microbial biomass) in the SG treatment were significantly higher than in the CK treatment, and even higher than MG and SA treatments. Compared with the CK treatment, treatments MG, SA, and SG significantly increased the multifunctionality index on average by 0.57, 0.23 and 0.76, respectively. Random forest modeling showed that the alpha-diversity and composition of bacterial communities, rather than fungal communities, drove the ecosystem multifunctionality. Moreover, we found that both the MG and SG treatments significantly improved bacterial network stability, which exhabited stronger correlations with ecosystem multifunctionality compared to fungal network stability. In summary, this study demonstrates that planting shrub and grasses altogether is a promising restoration mode that can enhance ecosystem multifunctionality and improve microbial diversity and stability in the alpine degraded grassland. [ABSTRACT FROM AUTHOR]

Background and objectives: Meat and meat products are susceptible to chemical and microbial spoilage during production, transportation, storage, and consumption. Meat's high moisture and nitrogen content of meat, as well as its suitable pH and fermentable carbohydrates, make it an ideal environment for spoilage and toxic bacteria and fungi. Food packaging can extend the shelf life of food products by inhibiting or retarding lipid oxidation and microbial growth, and edible packaging has been used to extend the shelf life of meat. Hydrocolloids are widely used in the food industry for a variety of purposes, including gelling agents, stabilizers, and texture improvers. Lepidium perfoliatum seed mucilage (LPSM) is used in traditional medicine to treat whooping cough, dry cough and lung infections and as a sedative, and due to its good physical, mechanical, and thermal properties, it can be used as a biodegradable packaging to improve the shelf life of various food products. However, polysaccharide-based coatings hardly have an antimicrobial or antioxidant effect, so antioxidant and antimicrobial compounds are usually included in edible coatings to improve their performance. Edible coatings enriched with plant essential oils, through controlling microbial growth, inhibiting lipid oxidation and improving the appearance of foods are widely used in food preservation. Materials and methods: T. carmanicus plant was dried at room temperature and then powdered using a mill. After that, 50 g of the powder was transferred to the Clevenger device containing 750 ml of distilled water, and the extraction process was carried out by distillation with water for 3 h. The obtained essential oil (TCEO) was collected in a glass container and stored at 4 °C. Its phenol content (based on Folin-Ciocalteu method), flavonoid content (based on aluminum chloride colorimetry method), antioxidant activity (based on DPPH and ABTS radical scavenging methods), and antimicrobial activity (based on disc diffusion agar, well diffusion agar, minimum inhibitory concentration, and minimum bactericidal concentration methods) against pathogenic bacteria (Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa, Listeria innocua, and Staphylococcus aureus) were evaluated. TCEO (0, 0.5, 1, 1.5%) was then added to the LPSM to prepare an edible coating to improve the shelf-life of lamb slices during cold storage (4 °C, 10 days). The physicochemical (pH, moisture content, hardness, peroxide value, and thiobarbituric acid value), microbial (total viable, psychrotrophic, E. coli, S. aureus, and fungi counts), and sensory (color, odor, texture, and overall acceptance) properties of the samples were evaluated during storage period. Results and discussion: The essential oil with 0.96% extraction yield contained 52.22 mg GAE/g total phenol and 18.43 mg QE/g total flavonoids. The antioxidant activity of TCEO was found to be 357.13 and 312.18 μg/ml based on DPPH and ABTS radical scavenging methods. Based on disc and well diffusion agar tests, S. aureus and P. aeruginosa were the most sensitive and resistant strains to the essential oil, respectively. Increasing the storage time caused a significant increase in the total count of viable bacteria, psychrotrophic bacteria, E. coli, S. aureus, and fungi (p < 0.05); however, this value decreased significantly with the increase in the concentration of the essential oil in the edible coating. Moreover, the use of LPSM-TCEO edible coating inhibited the extensive changes in pH, moisture, peroxide value, and thiobarbituric acid value in lamb slices during storage period. Also, increasing the concentration of TCEO in the edible coating caused the preservation of the sensory parameters of the samples during the storage period, and from the consumer's point of view, the edible coatings based on the LPSM enriched with TCEO did not show any negative effect on odor, color, texture, and overall acceptance of the lamb samples during cold storage. In general, the highest physicochemical stability, microbial stability, and overall acceptance was assigned to lamb sample coated with LPSM + 1.5% TCEO, and the bioactive coating was able to improve the shelf life of lamb slices (> 10 days). Conclusion: The results of this study showed that TCEO has high antioxidant and antimicrobial activity. The use of TCEO in an edible coating based on LPSM led to a decrease in the lipid oxidation of lamb and microbial growth compared to the uncoated sample. Therefore, the edible coating based on LPSM containing TCEO can be used to improve the shelf life of meat products. [ABSTRACT FROM AUTHOR]

The effect of High Hydrostatic Pressure (HHP) on Escherichia coli and Listeria innocua in carrot juice was evaluated just after pressurization and during refrigerated storage for 14 days. Samples were processed with different variants of pressure (300,400,500) and time (1 min, 5 min, and 10 min). The number of bacteria in the populations was analyzed using plating count methods. Required 5 log reduction was achieved only for L. innocua strains starting from 400 MPa for 5 min. E. coli strains displayed resistance to pressure, and the maximum reduction achieved was 2 log CFU/mL for the harshest process parameters. Sublethal injuries in the bacterial population were observed for all tested strains. According to two standardized ISO methods, selective conventional agars, TBX, and ALOA were used in the storage test. Additionally, the Thin Agar Layer (TAL) method was applied. In both used methods, the possibilities of recovery were provided. The regeneration was observed exclusively for L. innocua strains. The recovery of sublethally injured cells on ALOA and TAL did not differ statistically in every strain. In turn, results obtained for E. coli suggest that TBX may underestimate the number of HHP-injured bacteria.

Extending the shelf life of gluten-free bread (GFB) is a challenge. Mainly due to the ingredients used and their characteristics, GFB has numerous drawbacks such as unsatisfactory texture and rapid staling beyond a low nutritional value. In the present study, flaxseed oil cake extract (FOCE) was used to replace water (25–100%) in GFB formulations in order to test FOCE's potential to reduce GFB staling and extend microbial stability. Texture (TPA test), water activity (LF NMR), acidity (pH measurements) and microbiological quality of GFBs were tested. Moreover, the content of a lignan with broad health-promoting potential, secoisolariciresinol diglucoside (SDG), in GFB with FOCE was analyzed. The results showed that the use of FOCE enriched experimental GFB in valuable SDG (217–525 µg/100 g DM) while not causing adverse microbiological changes. A moderate level (25–50%) of FOCE did not change the main texture parameters of GFB stored for 72 h, the quality of which was comparable to control bread without FOCE. Meanwhile, higher proportions of FOCE (75–100% of water replacement) shortened GFB shelf life as determined by water activity and texture profile, suggesting that GFB with FOCE should be consumed fresh. To summarize, FOCE at moderate levels can add value to GFBs without causing a drop in quality, while still fitting in with the idea of zero waste and the circular economy. [ABSTRACT FROM AUTHOR]

The present study assessed the effectiveness of high pressure processing (HPP) for the quality maintenance of pitted sour cherries, with special regard to microbial stabilization and the maintenance of color and of chemical–nutritional properties. The HPP treatment (600 MPa for 3 min at 4 °C) was effective at minimizing the initial microbial load, which remained at negligible levels throughout 5 months of refrigerated storage. The color and total phytochemical content of sour cherries were not influenced by the HPP treatment and were maintained at levels comparable with the fresh product for 3 months of refrigerated storage. For longer storage periods, the typical red color decreased, in agreement with the content of total anthocyanins, which showed a significant decrease (up to 65% after 5 months). The antioxidant activity, measured by the ABTS and DPPH assays, was not affected by the HPP treatment, but slightly reduced during refrigerated storage. The study suggests that HPP may be exploited to extend the shelf life, while maintaining the fresh-like features of sour cherries, thus offering an alternative option to current preservation techniques (based on freezing or heating) commonly applied to this product. [ABSTRACT FROM AUTHOR]

Microbial development, enzymatic action, and chemical reactions influence the quality of untreated natural orange juice, compromising its organoleptic characteristics and causing nutritional value loss. Active low-density polyethylene (LDPE) films containing green tea extract (GTE) were previously prepared by a blown film extrusion process. Small bags were prepared from the produced films, which were then filled with fresh orange juice and stored at 4 °C. Ascorbic acid (AA) content, sugar content, browning index, color parameters, pH, total acidity (TA) and microbial stability were evaluated after 3, 7, and 14 days of storage. The packaging containing GTE maintained the microbial load of fresh juice beneath the limit of microbial shelf-life (6 log CFU/mL) for the bacterial growth, with a more prominent effect for LDPE with 3%GTE. Regarding yeasts and molds, only the CO_LDPE_3GTE package maintained the microbial load of fresh juice below the limit for up to 14 days. At 14 days, the lowest levels of AA degradation (32.60 mg/100 mL of juice) and development of brown pigments (browning index = 0.139) were observed for the packages containing 3% of GTE, which had a pH of 3.87 and sugar content of 11.4 g/100 mL of juice at this time. Therefore, active LDPE films containing 3% of GTE increase the shelf-life of fresh juice and can be a promising option for storage of this food product while increasing sustainability. [ABSTRACT FROM AUTHOR]

The aim of the current study was to explore the preservative effect of aqueous coriander extract and butylated hydroxytoluene (BHT) on the shelf life of refrigerated chicken patties for 9 days. For this purpose, BHT (100 ppm) and aqueous coriander extract (1%) was applied to improve the storage stability. The patties were evaluated for their physiochemical characterization including total phenolic content (TPC), thiobarbituric acid reactive substances (TBARS), peroxide value (PV), total carbonyl, metmyoglobin, and instrumental color, microbial analysis including (total plate count), and sensory attributes including (color and odor). The results showed that coriander extract has a significant (P <.05) effect in terms of delaying microbial growth, lipid and protein oxidation compared to BHT application. Likewise, higher phenolic contents were observed in patties treated with coriander extract. Conclusively, coriander extract did not impose any undesirable effect of physical attributes (instrumental color and color/odor) of cooked chicken patties. It is concluded that aqueous coriander extract is a plenteous source of various antioxidants and should be used as a functional food additive in meat products at 1% concentration without affecting the product's quality attributes. [ABSTRACT FROM AUTHOR]

High-throughput sequencing has become a critical tool for studying microbiomes by measuring relative microbiome profiling, although this typically overlooks the absolute abundance of microbiomes. Consequently, pathological, physiological, and ecological roles of microbial communities may be represented inaccurately. To address this, we estimated absolute abundances of soil microbiomes by combining amplicon sequencing with quantitative PCR. We collected soil samples (0–30 cm) at three sampling times (pre-planting, flowering, and maturity) from peanut plots subject to a long-term conventional rotation (peanut-cotton-cotton, CR) or sod-based rotation (bahiagrass-bahiagrass-peanut-cotton, SBR). Rotation and sampling time were important in shaping microbial communities. Relative to CR, SBR had greater microbial diversity, greater community stability, complexity and stability of bacterial-fungal networks, and greater richness and abundance of keystone taxa, which may make soil microbiomes more resilient to environmental changes among sampling times. SBR also showed significantly greater concentrations of total C and N, NO3−-N, resin-extractable P, Mg, Zn, Fe, and Cu, and greater potential N mineralization rates and C:N ratios, indicating that SBR's higher rotational diversity affected soil health in the topsoil. There were more significant relationships between soil nutrients and microbial community composition as well as keystone taxa under SBR, indicating that higher rotational diversity intensified ecological connections among soil, microbes, and crops. Our results suggest that a more complex and stable microbial network with greater richness and abundance of keystone taxa (primarily bacterial communities) had critical impacts on nutrient cycling and plant health and fitness under SBR, which are the main factors contributing to crop productivity. [ABSTRACT FROM AUTHOR]

Rapid urbanization considerably alters soil environment, biodiversity, and stability of terrestrial ecosystems. Soil microbial community, a key component of global biodiversity, plays a pivotal role in ecosystem stability and is highly vulnerable to urbanization. However, effects of urbanization on the diversity, stability, and network structure of soil microbial community remain poorly understood. Herein, we investigated the diversity and stability of soil microbial communities, including bacteria, fungi, and protists, across three regions with different levels of urbanization—urban, suburb, and ecoregion—using high-throughput sequencing techniques. Our results revealed that urbanization led to a notable decrease in the alpha diversity of soil microbial community, causing a significant reduction in soil stability, as assessed by the average variation degree (AVD). The loss of stability was linked to the diminished alpha diversity of the soil fungal and protistan communities, along with weakened interactions among bacteria, fungi, and protists. Notably, the majority of keystone species identified through network analysis were classified as bacteria (Proteobacteria) and displayed a strong positive correlation with the environmental factors influencing AVD. This highlights that the variability of bacteria and the immutability of fungi and protists are important to sustain soil microbial stability. Furthermore, structural equation models indicated that protistan diversity primarily drove soil microbial stability across all regions studied. In the suburban and ecoregion areas, soil microbial stability was directly influenced by the soil properties, bacterial diversity, and keystone species, as well as indirectly affected by heavy metals. These results underscore how urbanization can reduce the stability of soil microbial community via declined diversity and network complexity, whereas the establishment of ecoregions maybe contribute to preserve the diversity and stability of soil microbial community. [Display omitted] • Urbanization decreased the diversity and stability of soil microbial community. • Bacteria were more sensitive response to urbanization than fungi and protists. • Soil microbial stability was mainly determined by protistan community diversity. • Increased network complexity improved the stability of soil microbial community. [ABSTRACT FROM AUTHOR]

[Display omitted] • Activated sludge contains large amounts of novel and diverse phages. • Phages infect dominant prokaryotes in lysogenic mode as adaptive strategies. • Generalist prokaryotes and polyvalent phages enhance microbiome connectivity. • Antiviral systems can tolerate lysogenic phage infection but not lytic infection. • Symbiotic phage communities harbor AMGs that could improve floc stability. Despite the importance of phages for the dynamics and functions of microbial communities, it remains largely unexplored how symbiotic phages adapt in activated sludge systems and influence microbial aggregate stability, which is critical for clarification and reliable performance. Based on 12,127 phage contigs recovered from 12 activated sludge microbiomes, the symbiotic phages exhibited broad host ranges and infected dominant prokaryotes in activated sludge. Moreover, these phage communities exhibited high lysogenicity (49% to 66% lysogenic phages) and harbored diverse auxiliary metabolic genes (AMGs) that could enhance microbial aggregate stability, such as genes coding for lipopolysaccharide, peptidoglycan, and extracellular polysaccharide biosynthesis. Additionally, prokaryotic antiviral systems were widely distributed in dominant prokaryotes, particularly the Restriction-Modification (RM) and CRISPR-Cas systems, which could mitigate potential harmful phage infections. Overall, this study reveals the contemporary beneficial relationship between phages and prokaryotic hosts in activated sludge microbiomes and the potential benefits of symbiotic phages on floc stability. [ABSTRACT FROM AUTHOR]

Host-associated microbial dynamics are influenced by dietary and immune factors, but how exogenous microbial exposure shapes host-microbe dynamics remains poorly characterized. To investigate this phenomenon, we characterized the skin, rectum, and respiratory tract-associated microbiota in four aquarium-housed dolphins daily over a period of 6 weeks, including administration of a probiotic during weeks 4 to 6. The environmental bacterial sources were also characterized, including the animals' human handlers, the aquarium air and water, and the dolphins' food supply. Continuous microbial exposure occurred between all sites, yet each environment maintained a characteristic microbiota, suggesting that the majority of exposure events do not result in colonization. Small changes in water physicochemistry had a significant but weak correlation with change in dolphin-associated bacterial richness but had no influence on phylogenetic diversity. Food and air microbiota were the richest and had the largest conditional influence on other microbiota in the absence of probiotics, but during probiotic administration, food alone had the largest influence on the stability of the dolphin microbiota. Our results suggest that respiratory tract and gastrointestinal epithelium interactions with air- and food-associated microbes had the biggest influence on host-microbiota dynamics, while other interactions, such as skin transmission, played only a minor role. Finally, direct oral stimulation with a foreign exogenous microbial source can have a profound effect on microbial stability. IMPORTANCE These results provide valuable insights into the ecological influence of exogenous microbial exposure, as well as laying the foundation for improving aquarium management practices. By comparing data for dolphins from aquaria that use natural versus artificial seawater, we demonstrate the potential influence of aquarium water disinfection procedures on dolphin microbial dynamics.

The effect of chitosan coating enriched with free and nanoencapsulated Satureja montana L. essential oil (EO) on microbial, antioxidant and sensory characteristics of beef was analyzed. Different concentrations of free Satureja montana L. EO (SMEO) and nanoparticles (CNPs) were added to chitosan coatings, namely 0.25%, 0.5% and 1%. The beef samples were immersed in the chitosan coatings and stored at +4 °C for 20 days. In this period, the changes in pH value, total viable count (TVC), lactic acid bacteria, psychrophilic bacteria and Pseudomonas spp. were analyzed. The lipid oxidation of beef was determined by the TBAR assay, while sensory analysis was performed by means of the descriptive evaluation method. Generally, the influence of chitosan coating with CNPs on the growth of the tested microorganisms was more pronounced compared to SMEO. Treatment with coating enriched with 1% CNPs resulted in the reduction in TVC and Pseudomonas spp. by 2.4 and 3 log CFU/g, compared to the control, respectively. Additionally, all applied coatings with SMEO and CNPs resulted in the prolonged oxidative stability of the meat The addition of free SMEO created an unnatural aroma for the evaluators, while this odor was neutralized by nanoencapsulation. The durability of color, smell and general acceptability of beef was significantly increased by application of chitosane coatings with the addition of SMEO or SMEO-CNPs, compared to the control. This research indicates the potential application of enriched chitosan coatings in beef preservation in order to improve meat safety and prolong shelf-life. [ABSTRACT FROM AUTHOR]

The effect of High Hydrostatic Pressure (HHP) on Escherichia coli and Listeria innocua in carrot juice was evaluated just after pressurization and during refrigerated storage for 14 days. Samples were processed with different variants of pressure (300, 400, 500) and time (1 min, 5 min, and 10 min). The number of bacteria in the populations was analyzed using plating count methods. Required 5 log reduction was achieved only for L. innocua strains starting from 400 MPa for 5 min. E. coli strains displayed resistance to pressure, and the maximum reduction achieved was 2 log CFU/mL for the harshest process parameters. Sublethal injuries in the bacterial population were observed for all tested strains. According to two standardized ISO methods, selective conventional agars, TBX, and ALOA were used in the storage test. Additionally, the Thin Agar Layer (TAL) method was applied. In both used methods, the possibilities of recovery were provided. The regeneration was observed exclusively for L. innocua strains. The recovery of sublethally injured cells on ALOA and TAL did not differ statistically in every strain. In turn, results obtained for E. coli suggest that TBX may underestimate the number of HHP-injured bacteria. [ABSTRACT FROM AUTHOR]

An eggplant-based salad, called aubergine salad (AS), is a traditional appetizer and as such, is quite popular in the Mediterranean area. It is widely produced either on a home scale or on an industrial scale and widely consumed. However, there are cases where preservatives (such as sodium benzoate and potassium sorbate) are added in order to extend the shelf life of the product. In the present study, the stability of this delicatessen against oxidation and microbial spoilage was evaluated, with or without preservatives. The physicochemical properties of the salad were evaluated, along with the tocopherol content, resistance to oxidation, and microbial count. According to the results, it is evident that the induction period of AS is 16% (in the case that preservatives were used) and 26% (in the case without preservatives) increased, compared to a control sample (plain soybean oil). This can be attributed to the increased content in tocopherols, and more specifically to α-tocopherol. Furthermore, the addition of preservatives resulted in increased storage days and a reduction of microorganisms. However, in both cases, the AS-prepared salad exhibited a self-stabilization ability after 13 days, negating the need for preservatives. [ABSTRACT FROM AUTHOR]

Microbial challenge in-use studies are performed to evaluate the potential for microbial proliferation in preservative-free single-dose biological products after first puncture and potential accidental contamination during dose preparation (e.g., reconstitution or dilution) and storage. These studies, in addition to physicochemical in-use stability assessments, are used as part of product registration to define in-use hold times in Prescribing Information and in the pharmacy manual in the case of clinical products. There are no formal guidance documents describing regulator expectations on how to conduct microbial challenge in-use studies and interpret microbial data to assign in-use storage hold times. In lieu of guidance, US Food and Drug Administration (FDA) regulators have authored publications and presentations describing regulator expectations. Insufficient or unavailable microbial challenge data can result in shortened in-use hold times, thus microbial challenge data enables flexibility for health care providers (HCPs) and patients while ensuring patient safety. A cross-industry/FDA in-use microbial working group was formed through the Innovation & Quality (IQ) Consortium to gain alignment among industry practice and regulator expectations. The working group assessed regulatory guidance, current industry practice via a blinded survey of IQ Consortium member companies, and scientific rationale to align on recommendations for experimental design, execution of microbial challenge in-use studies, and a decision tree for microbial data interpretation to assign in-use hold times. Besides the study execution and data interpretation, additional considerations are discussed including the use of platform data for clinical stage products, closed system transfer devices (CSTDs), transport of dose solutions, long infusion times, and the use of USP <797> by HCPs for preparing sterile drugs for administration. The recommendations provided in this article will help streamline biological product development, ensure consistency on assignment of in-use hold times in biological product labels across industry, and provide maximum allowable flexibility to HCPs and patients while ensuring patient safety., (© PDA, Inc. 2024.)

In this study, Citrus sinensis essential oil was extracted by hydrodistillation method and the results of gas chromatography-mass spectrometry showed that the oil is rich in limonene (87.86%). Total phenol and flavonoid contents of the CSEO were 125.41 mg GAE/g and 32.50 mg QE/g, respectively. Its antioxidant activity was found to be 39.75 and 52.43%, based on DPPH and ABTS radical scavenging activity, respectively. The presence of limonene in the CSEO was confirmed by furrier transform infrared spectroscopy. The CSEO was then combined with Cordia myxa fruit mucilage to produce an edible coating in order to improve the microbial and oxidative stability of buffalo meat during storage (10 days, 4 °C). Results showed that the growth of total viable count, psychrotrophic bacteria, E. coli, Staphylococcus aureus, and fungi were significantly inhibited in the buffalo meat samples coated with CMFM+CSEO. The CMFM+CSEO edible coating was also more effective in inhibiting the oxidation progression and moisture and texture losses, in comparison with control sample. According to the sensory evaluation results, the CMFM+CSEO edible coating increased the shelf-life of buffalo meat samples; the samples were acceptable even at the end of storage period (10 days), but the control sample was unacceptable after 7 days of storage. Therefore, the edible coating based on Cordia myxa fruit mucilage and Citrus sinensis essential oil could be used as a natural preservative to increase the shelf-life of buffalo meat and other meat products.

The aim of this paper was to study the microbiological stability of bio-based composite building materials, which are made using organic-rich lake sediments (further – sapropel) with lime and magnesium cement as binders and hemp shives as filler. The microbial stability properties of the obtained composite materials were investigated and compared to similar composites. Because of their high organic content, these materials are prone to biodegradation; therefore, they were coated with ALINA LIFE TM organoclay coating, which helps to extend the product life, reducing the rate of biodegradation compared to the biocides used in industry. The effect of the coating on the resistance to decay by the Aspergillus versicolor, Penicillium chrysogenum, Alternaria alternata, Cladosporium herbarum, Chaetomium sp. and Trichoderma asperellum fungi was investigated under different conditions: relative humidity modes of 75% and 99% at 20°C for 45 days and four months. The results indicated that the composites made of sapropel and lime have similar microbial stability properties as lime and magnesium cement binder composite materials. ALINA LIFE TM organoclay coating showed advanced resistance to biodegradation; sapropel-lime composites have shown several good properties that make them suitable to be considered for use in the construction material industry.

Extending the shelf life of gluten-free bread (GFB) is a challenge. Mainly due to the ingredients used and their characteristics, GFB has numerous drawbacks such as unsatisfactory texture and rapid staling beyond a low nutritional value. In the present study, flaxseed oil cake extract (FOCE) was used to replace water (25–100%) in GFB formulations in order to test FOCE’s potential to reduce GFB staling and extend microbial stability. Texture (TPA test), water activity (LF NMR), acidity (pH measurements) and microbiological quality of GFBs were tested. Moreover, the content of a lignan with broad health-promoting potential, secoisolariciresinol diglucoside (SDG), in GFB with FOCE was analyzed. The results showed that the use of FOCE enriched experimental GFB in valuable SDG (217–525 µg/100 g DM) while not causing adverse microbiological changes. A moderate level (25–50%) of FOCE did not change the main texture parameters of GFB stored for 72 h, the quality of which was comparable to control bread without FOCE. Meanwhile, higher proportions of FOCE (75–100% of water replacement) shortened GFB shelf life as determined by water activity and texture profile, suggesting that GFB with FOCE should be consumed fresh. To summarize, FOCE at moderate levels can add value to GFBs without causing a drop in quality, while still fitting in with the idea of zero waste and the circular economy.

The present study assessed the effectiveness of high pressure processing (HPP) for the quality maintenance of pitted sour cherries, with special regard to microbial stabilization and the maintenance of color and of chemical–nutritional properties. The HPP treatment (600 MPa for 3 min at 4 °C) was effective at minimizing the initial microbial load, which remained at negligible levels throughout 5 months of refrigerated storage. The color and total phytochemical content of sour cherries were not influenced by the HPP treatment and were maintained at levels comparable with the fresh product for 3 months of refrigerated storage. For longer storage periods, the typical red color decreased, in agreement with the content of total anthocyanins, which showed a significant decrease (up to 65% after 5 months). The antioxidant activity, measured by the ABTS and DPPH assays, was not affected by the HPP treatment, but slightly reduced during refrigerated storage. The study suggests that HPP may be exploited to extend the shelf life, while maintaining the fresh-like features of sour cherries, thus offering an alternative option to current preservation techniques (based on freezing or heating) commonly applied to this product.

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Microbial development, enzymatic action, and chemical reactions influence the quality of untreated natural orange juice, compromising its organoleptic characteristics and causing nutritional value loss. Active low-density polyethylene (LDPE) films containing green tea extract (GTE) were previously prepared by a blown film extrusion process. Small bags were prepared from the produced films, which were then filled with fresh orange juice and stored at 4 °C. Ascorbic acid (AA) content, sugar content, browning index, color parameters, pH, total acidity (TA) and microbial stability were evaluated after 3, 7, and 14 days of storage. The packaging containing GTE maintained the microbial load of fresh juice beneath the limit of microbial shelf-life (6 log CFU/mL) for the bacterial growth, with a more prominent effect for LDPE with 3%GTE. Regarding yeasts and molds, only the CO_LDPE_3GTE package maintained the microbial load of fresh juice below the limit for up to 14 days. At 14 days, the lowest levels of AA degradation (32.60 mg/100 mL of juice) and development of brown pigments (browning index = 0.139) were observed for the packages containing 3% of GTE, which had a pH of 3.87 and sugar content of 11.4 g/100 mL of juice at this time. Therefore, active LDPE films containing 3% of GTE increase the shelf-life of fresh juice and can be a promising option for storage of this food product while increasing sustainability.

Saccharomyces cerevisiae var. diastaticus is a feared contaminant in the brewing industry, causing super‐attenuation and deterioration in beer quality. The aim of this study was to monitor parameters of bottled lager beer contaminated with Saccharomyces cerevisiae var. diastaticus. Two bottled lagers with original extracts of 10.2 and 11.6% (w/w) were inoculated at 3 ± 1 or 300 ± 50 CFU/mL and stored at 8 or 23°C. Changes in the concentration of real extract, alcohol, turbidity, sugars and increase in 4‐vinyl guaiacol were monitored over 14 weeks of storage. The most significant changes were observed in beers stored at 23°C for both concentrations of contaminant. Cold storage at 8°C delayed indicators of spoilage associated with contamination by Saccharomyces cerevisiae var. diastaticus. © 2021 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The effect of chitosan coating enriched with free and nanoencapsulated Satureja montana L. essential oil (EO) on microbial, antioxidant and sensory characteristics of beef was analyzed. Different concentrations of free Satureja montana L. EO (SMEO) and nanoparticles (CNPs) were added to chitosan coatings, namely 0.25%, 0.5% and 1%. The beef samples were immersed in the chitosan coatings and stored at +4 °C for 20 days. In this period, the changes in pH value, total viable count (TVC), lactic acid bacteria, psychrophilic bacteria and Pseudomonas spp. were analyzed. The lipid oxidation of beef was determined by the TBAR assay, while sensory analysis was performed by means of the descriptive evaluation method. Generally, the influence of chitosan coating with CNPs on the growth of the tested microorganisms was more pronounced compared to SMEO. Treatment with coating enriched with 1% CNPs resulted in the reduction in TVC and Pseudomonas spp. by 2.4 and 3 log CFU/g, compared to the control, respectively. Additionally, all applied coatings with SMEO and CNPs resulted in the prolonged oxidative stability of the meat The addition of free SMEO created an unnatural aroma for the evaluators, while this odor was neutralized by nanoencapsulation. The durability of color, smell and general acceptability of beef was significantly increased by application of chitosane coatings with the addition of SMEO or SMEO-CNPs, compared to the control. This research indicates the potential application of enriched chitosan coatings in beef preservation in order to improve meat safety and prolong shelf-life.

In this study, Citrus sinensis essential oil was extracted by hydrodistillation method and the results of gas chromatography-mass spectrometry showed that the oil is rich in limonene (87.86%). Total phenol and flavonoid contents of the CSEO were 125.41 mg GAE/g and 32.50 mg QE/g, respectively. Its antioxidant activity was found to be 39.75 and 52.43%, based on DPPH and ABTS radical scavenging activity, respectively. The presence of limonene in the CSEO was confirmed by furrier transform infrared spectroscopy. The CSEO was then combined with Cordia myxa fruit mucilage to produce an edible coating in order to improve the microbial and oxidative stability of buffalo meat during storage (10 days, 4 °C). Results showed that the growth of total viable count, psychrotrophic bacteria, E. coli, Staphylococcus aureus, and fUngi were significantly inhibited in the buffalo meat samples coated with CMFM+CSEO. The CMFM+CSEO edible coating was also more effective in inhibiting the oxidation progression and moisture and texture losses, in comparison with control sample. According to the sensory evaluation results, the CMFM+CSEO edible coating increased the shelf-life of buffalo meat samples; the samples were acceptable even at the end of storage period (10 days), but the control sample was unacceptable after 7 days of storage. Therefore, the edible coating based on Cordia myxa fruit mucilage and Citrus sinensis essential oil could be used as a natural preservative to increase the shelf-life of buffalo meat and other meat products. [ABSTRACT FROM AUTHOR]

The aim of this paper was to study the microbiological stability of bio-based composite building materials, which are made using organic-rich lake sediments (further - sapropel) with lime and magnesium cement as binders and hemp shives as filler. The microbial stability properties of the obtained composite materials were investigated and compared to similar composites. Because of their high organic content, these materials are prone to biodegradation; therefore, they were coated with ALINA LIFE TM organoclay coating, which helps to extend the product life, reducing the rate of biodegradation compared to the biocides used in industry. The effect of the coating on the resistance to decay by the Aspergillus versicolor, Penicillium chrysogenum, Alternaria alternata, Cladosporium herbarum, Chaetomium sp. and Trichoderma asperellum fungi was investigated under different conditions: relative humidity modes of 75% and 99% at 20°C for 45 days and four months. The results indicated that the composites made of sapropel and lime have similar microbial stability properties as lime and magnesium cement binder composite materials. ALINA LIFE TM organoclay coating showed advanced resistance to biodegradation; sapropel-lime composites have shown several good properties that make them suitable to be considered for use in the construction material industry. [ABSTRACT FROM AUTHOR]

Type 3 sourdoughs, which are starter culture-initiated and subsequently backslopped, are less studied than other sourdough types. Yet, they can serve as a model to assess how competitive starter culture strains for sourdough production are and how the microbial composition of such sourdoughs may evolve over time. In the present study, Limosilactobacillus fermentum IMDO 130101 was used to produce Type 3 sourdoughs, prepared from wheat and wholemeal wheat flours. Therefore, an initial fermentation of the flour-water mixture was performed at 30 °C for 48 h. This was followed by cold storage-backslopping cycles, consisting of refreshments (50 %, v/v), fermentation steps of 16 h, and storage at 4 °C each week, every three weeks, and every six weeks. The microbial dynamics (culture-dependent and -independent approaches) and metabolite dynamics were measured. In all sourdoughs produced, starter culture strain monitoring, following an amplicon sequence variant approach, showed that Liml. fermentum IMDO 130101 prevailed during one month when the sourdoughs were refreshed each week, during 24 weeks when the sourdoughs were refreshed every three weeks, and during 12 weeks when the sourdoughs were refreshed every six weeks. This suggested the competitiveness and robustness of Liml. fermentum IMDO 130101 for a considerable duration but also showed that the strain is prone to microbial interference. For instance, Levilactobacillus brevis and Pediococcus spp. prevailed upon further cold storage and backslopping. Also, although no yeasts were inoculated into the flour-water mixtures, Kazachstania unispora , Torulaspora delbrueckii , and Wickerhamomyces anomalus were the main yeast species found. They appeared after several weeks of storage and backslopping, which however indicated the importance of an interplay between LAB and yeast species in sourdoughs. The main differences among the mature sourdoughs obtained could be explained by the different flours used, the refreshment conditions applied, and the sampling time (before and after backslopping). Finally, the metabolite quantifications revealed continued metabolite production during the cold storage periods, which may impact the sourdough properties and those of the breads made thereof. • Limosilactobacillus fermentum is a robust sourdough starter culture. • The amplicon sequence variant approach is a powerful tool to closely monitor this starter culture strain. • Cold storage-backslopping cycles influenced the appearance of yeasts. • The sourdough metabolites were mainly influenced by the flour type. • Metabolite production occurred mainly during initial fermentation and cold storage. [ABSTRACT FROM AUTHOR]

Fermentation has recently been rediscovered as an attractive technique to process legumes, as it can improve the nutritional quality and value of the end product. This study investigated the dynamics and stability of the microbial communities in spontaneously fermented sourdoughs made from flours of two cultivars of faba beans and two cultivars of peas. Sourdoughs were established by the backslopping technique, and the microbial development at 22 °C and 30 °C was followed by culture dependent and culture independent methods. The utilization of substrates and formation of metabolites were also determined by high-performance liquid chromatography. A stable pH was reached in all the sourdoughs after 11–15 days of daily backslopping. Lactic acid bacteria and yeast from pH stable sourdoughs were isolated, characterized and identified. The fermentation temperature influenced the development of the microbial community and the substrate utilization during spontaneous fermentation. In the 30 °C fermentations, one species dominated (Lactiplantibacillus plantarum/pentosus), a lower pH was achieved, and the available substrates were more extensively converted. The 22 °C fermentation resulted in a more diverse microbial community (Lactiplantibacillus , Leuconostoc , Pediococcus), a higher pH, and more residual substrates were available after fermentation. Yeasts were only detected in one of the pea sourdoughs fermented at 30 °C, with Saccharomyces cerevisiae being the dominant species. Nearly all sourdoughs were depleted of maltose after 24 h fermentation cycles, and higher levels of lactic and acetic acid were detected in 30 °C fermen-tations. This research adds to our understanding of the autochthonous microbial community present in faba beans and peas as well as their natural capacity to establish themselves and ferment legume flours. These findings enhance the possibilities of utilizing and improving plant based protein sources. • Lactic acid bacteria and yeast were isolated from spontaneous legume fermentations. • Temperature was a selective factor for the bacterial composition in mature sourdoughs. • The bacterial composition and pH remained stable throughout the weekly propagation. [ABSTRACT FROM AUTHOR]

The need to reduce the content of questionable health preservatives leads to the search for new methods to extend the shelf-life of meat products. The spectrum of possible approaches includes physical methods and the use of additives from natural sources. In this study, we examined the influence of the combination of high-pressure processing (HPP) and the addition of natural antimicrobials on the shelf-life of cooked ham. The samples of cooked ham were produced in a professional meat processing plant. One half of the samples were produced according to a traditional recipe, and the other was enriched with potassium lactate in the form of a commercial product PURASAL® Hirer P Plus. This product is produced via sugar fermentation and contains high levels of potassium lactate, a compound with high antimicrobial activity. Cooked hams were inoculated by bacteria Serratia liquefaction, vacuum packaged and treated by HPP. Packaged ham samples were stored at 3°C for 40 days and the total microbial count was examined during this storage period in defined intervals. The combination of HPP and potassium lactate from natural sources significantly reduced the total microbial counts in cooked hams and, thus, could be a suitable solution for the meat industry.

Demand for minimally processed ready-to-eat pomegranate arils increased in the market over the past decade due to their high nutritional value, sensory characteristics, convenience, and health benefits. The objective of this study was therefore to investigate the effect of ascorbic acid coating and modified atmosphere packaging (MAP) on the physicochemical, microbiological, sensory quality characteristics and shelf life of pomegranate arils Shishe-Kab cultivar. Treatments were: passive-MAP, passive-MAP (washed arils with water), active-MAP1 (35.2% O2, 0.3% CO2, 64.5% N2), active-MAP2 (15.5% O2, 20% CO2, 64.5% N2), active-MAP1 + ascorbic acid, and active-MAP2 + ascorbic acid. The results indicated that experimental treatments significantly influenced some of the physicochemical parameters of pomegranate arils as pH and redness increased. A combination of active packaging (MAP1 and MAP2) and ascorbic acid coating preserved the redness of arils and had higher a* values compared to control and other treatments after 20 days of cold storage. Interestingly, samples packed in active-MAP with or without ascorbic acid coating helped to keep the sensory qualities with acceptable eating quality, as well as significantly extended the shelf life (about 30%) of pomegranate arils 'Shishe-Kab' cultivar in refrigerated storage at 3 °C compared to passive MAP. In conclusion, the results revealed that higher O2 or CO2 concentration than air in packages (active-MAP) alone and plus ascorbic acid coating can prolong the lag time of microorganisms and extend the shelf life of pomegranate arils more than 20 days during cold storage at 3 °C. Overall, sensory scores were also higher in ascorbic acid coated arils that were quite acceptable even after 20 days of storage at 3 °C. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of a hurdle technology approach include ultrasound treatment and antimicrobial nanocomposite packaging on the microbial, physiochemical, and sensory properties of fresh strawberry juice during cold storage. The beneficial impact of coupling ultrasonication (US) for 4 and 12 min, with antimicrobial nanocomposites packaging based on low-density polyethylene (LDPE) containing nano-ZnO (3:100 w/w) as compared to pure packaging based on LDPE (Pure packaging + US 4, Pure packaging + US 12, Nano packaging + US 4, Nano Packaging + US 12, and Pure packaging (Control)) on the shelf life of fresh strawberry juices was considered during 0, 7, 14, 21, 28, and 35 days (4 °C). The lowest growth of microorganisms, polyphenol oxidase and pectin methyl esterase activities, ascorbic acid content, total phenols, and total anthocyanins degradation was detected in strawberries juices treated with Nano Packaging + US 12. Moreover, the juice samples treated with Nano Packaging + US 4 showed the highest-ranked sensory attributes compared to the other samples up to 14 days. These results introduced the way for hurdle technology applications involving a combination of antimicrobial packaging containing nano-ZnO with short time sonication in enhancing the quality of fresh strawberry juice during cold storage. [ABSTRACT FROM AUTHOR]

Vegetable milks are fast gaining attention on the global scale as the possible alternatives due to concerns associated with milk consumption. In particular, issues varying from allergenic constituents and lactose intolerance to social and religious beliefs among consumers have induced an increase in the market demand for vegetable milks. Their concomitant nutritional and bioactive components appraise them of the suitable profile for the food-based carriage and delivery of probiotics. More so, the presence of prebiotics in their natural configuration makes them serviceable for the assurance of the needed probiotic viability, subsequent to their exposure to digestive conditions. On another note, their availability, ease of processing, and cost-effectiveness have been established as other possible rationales behind their adoption. This chapter comprehensively delineates the probiotic and prebiotic food-usage of vegetable milks. Captions related with consumer concerns, processing operations, nutritional and prebiotic constitutions, metabolic interactions during probiotic fermentation, and associated health benefits of vegetable milks are discoursed. [ABSTRACT FROM AUTHOR]

Freshly prepared pastes from blanched mealworms (Tenebrio molitor) are highly perishable and prone to microbial and chemical changes upon storage due to their high water activity, near–neutral pH, and their rich nutrient profile. Their shelf life is short unless preservation methods are used. In this study, the effects of preservatives (sodium nitrite and sodium lactate) and lactic acid fermentation (with the starter cultures Bactoferm® F-LC and Lactobacillus farciminis) on the microbiological and the chemical stability of mealworm pastes stored at 4°C were compared. During the storage experiment, the pH, water activity, color, microbial counts, and fat oxidation were monitored. In addition, the prevalence of the pathogens Bacillus cereus, Salmonella spp., and Listeria monocytogenes were studied. Microbial quality evaluation of the mealworm pastes showed that the addition of preservatives did not inhibit microbial growth during refrigerated storage, reaching the upper limits for consumption between seven and 14 days. By contrast, the acid medium (pH < 4.50) created by fermentation stabilized all microbial populations investigated, indicating that these pastes could be consumed up to (at least) 8 weeks of refrigerated storage. L. monocytogenes, Salmonella, and B. cereus were not detected in any of the samples and lipid oxidation of the samples was minimal. Altogether, this study shows that lactic acid fermentation can be used successfully to inhibit microbial growth, to maintain chemical quality, and to extend the shelf life of mealworm pastes stored at 4°C.

Freshly prepared pastes from blanched mealworms (Tenebrio molitor) are highly perishable and prone to microbial and chemical changes upon storage due to their high water activity, near–neutral pH, and their rich nutrient profile. Their shelf life is short unless preservation methods are used. In this study, the effects of preservatives (sodium nitrite and sodium lactate) and lactic acid fermentation (with the starter cultures Bactoferm® F-LC and Lactobacillus farciminis) on the microbiological and the chemical stability of mealworm pastes stored at 4°C were compared. During the storage experiment, the pH, water activity, color, microbial counts, and fat oxidation were monitored. In addition, the prevalence of the pathogens Bacillus cereus , Salmonella spp., and Listeria monocytogenes were studied. Microbial quality evaluation of the mealworm pastes showed that the addition of preservatives did not inhibit microbial growth during refrigerated storage, reaching the upper limits for consumption between seven and 14 days. By contrast, the acid medium (pH < 4.50) created by fermentation stabilized all microbial populations investigated, indicating that these pastes could be consumed up to (at least) 8 weeks of refrigerated storage. L. monocytogenes , Salmonella , and B. cereus were not detected in any of the samples and lipid oxidation of the samples was minimal. Altogether, this study shows that lactic acid fermentation can be used successfully to inhibit microbial growth, to maintain chemical quality, and to extend the shelf life of mealworm pastes stored at 4°C. [ABSTRACT FROM AUTHOR]

Copyright of Veterinarska Stanica is the property of Croatian Veterinary Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to evaluate the effect of refrigerated storage on the microbial properties and organoleptic quality of Bologna-type turkey sausage, in which fat was partially replaced with pea fibre or potato starch. Each manufactured sausage had lower counts of Esherichia coli and enterobacteria than 1 log CFU·g−1, counts were below 2 log CFU·g−1 for Staphylococcus aureus, moreover, no Salmonella spp. were found in any of the sausages. The counts of mesophilic aerobic bacteria did not exceed 4 log CFU·g−1 for each sausage formulation during four-week storage at 4 °C. Spectrocolorimetric measurements revealed that there was no decline in luminosity (L*) and redness (a*) by time, namely colour fading did not occur. Saltiness and juiciness values of sausages were directly proportional. Low-fat sausages were perceived less salty than full-fat analogue with the same salt content at the early stage of storage. Nevertheless, this phenomenon was temporary as sausages had the same saltiness at the end of four-week storage period. Sausages, in which 25% of fat was substituted with pea fibre or potato starch, were assessed as having the same odour, consistency, taste, and overall impact like control during the four-week refrigerated storage. [ABSTRACT FROM AUTHOR]

This study started with the development of juice from sapodilla (Manilkara zapota L.) fruit. Among three formulations, sapodilla juice with the combination of 50% pure sapodilla juice, 25oBrix, and 0.40% of titratable acidity have gained the highest score in the hedonic sensory test, with overall acceptability ranging from “like slightly” to “like moderately”. Formulated sapodilla juice and pure sapodilla juice were analysed for their total phenolic and ascorbic acid contents, pH, total soluble solid and titratable acidity. The formulated sapodilla juice has lower pH (3.35), higher titratable acidity content (0.40%) and total soluble solid (25oBrix) than pure sapodilla juice. The total phenolic (469.82 mg GAE/L) and ascorbic acid contents (3.60 mg/100 mL) of formulated sapodilla juice which consists only 50% of sapodilla juice showed the lower value than the pure sapodilla juice. Formulated sapodilla juice with lower pH will be less susceptible to enzymatic browning. In microbiology total plate count, no colony formed on the formulated juice, whereas the mean number of colony forming units (CFU) in pure juice was 169318.18 CFU/ml juice stored in room temperature (28°C) for a week. These results revealed that the formulated juice had better microbial stability than pure juice.

Atlantic salmon (Salmo salar) quality was evaluated by hyperbaric storage at low temperature (HS/LT; 40–60 MPa, 5–15 °C) and compared with control samples stored at the same storage temperatures (5–15 °C) and atmospheric pressure (AP). Results showed that HS/LT was efficient to slowdown spoilage microbial growth, with additional inactivation at 60 MPa/10 °C after 50 days. Contrarily, AP-5/10 °C samples exceeded the established limit after 15 days. Furthermore, the established limit of total volatile base-nitrogen was surpassed at 60 MPa/10 °C only after 30 days (contrarily to 6 days at AP/10 °C), but with stable trimethylamine-nitrogen content in the former. Formaldehyde and dimethylamine-nitrogen contents increased after 6 days of HS/LT, but only the former progressively increased until the 10th day, indicating a possible formation by the action of enzymatic activity, but also by other chemical reactions. Additionally, HS/LT slightly increased secondary product content from the lipid oxidation, although to a lower extent compared with AP (at the different storage temperatures). Concluding, HS/LT may represent an interesting methodology to control microbial activity and important physicochemical parameters (such as volatile amines, colour, and lipid oxidation) of Atlantic salmon muscle portions for 15–30 days, compared with 6 days for AP/5 °C (conventional refrigeration). [ABSTRACT FROM AUTHOR]

Traditional Greek yogurt-based salad Tzatziki is one of the most popular ready-to-eat deli salads in Greece. The objective of this study was to estimate the microbial stability of Tzatziki, with and without chemical preservatives, using a rapid method. Determination of the microbial count was carried out using the bioluminescence method (ATP) and traditional microbiological analysis, plate-counting method (CFU) in various batches of the final product of Tzatziki. The results showed that the Tzatziki salad without preservatives initially gave higher relative light units (RLU) values (79,532) than the same salad with preservatives (43,198) because the potassium sorbate and the sodium benzoate, used in recipe, appeared to suspend the action of microorganisms. After incubation in two different substrates, MacConkey and Sabouraud, the Tzatziki salad without preservatives gave higher RLU values (9,488 and 16,176, respectively) than the salad with preservatives (12,780 and 12,005, respectively). In the two selective substrates, differences appeared between the two methods of microbial count (RLU and CFU). While RLU values were roughly at the same level, the CFU values presented significant differences (p < 0.05). It was also shown that there was a strong correlation (R2 = 0.93-0.95) between bacterial counts estimated by traditional CFU and ATP methods. As expected, the dominant microbial population in Tzatziki was Lactobacillus spp., originated from yogurt. Coliforms and yeasts were not able to survive in this environment. Generally, according to the results, Greek traditional Tzatziki salad was a microbial stable product and the bioluminescence method could be a rapid method to determine its microbial state.

Abstract This study investigated the establishment of wheat stable sourdoughs, both in liquid (dough yield = 330) and firm (dough yield = 154) conditions, by inoculating 5 strains of different lactic acid bacteria species together with either a Saccharomyces cerevisiae or a Candida milleri strain. Real propagation cycles, consisting of ten refreshments, were simulated to assess the behaviour and robustness of the microorganisms. The results indicated stable microbial communities from seventh backslopping in all the tested conditions, with some differences among the strains. Lactobacillus farciminis Lf19 proved to be the most competitive strain, maintaining high concentrations throughout the refreshments at different dough yield, while Lactobacillus rossiae Lr9 resulted the less performing strain. Due to the longer refreshment time (24h instead of 6h) and to the presence of Saccharomyces cerevisiae , Lactobacillus sanfranciscensis Ls51 was probably affected by the maltose depletion in liquid condition. At sourdoughs stability, the main technological characteristics (pH, total titratable acidity, fermentation quotient) were in agreement with those reported for mature sourdoughs. Overall, this study evaluated the effect of modifying some parameters (dough yield, refreshment time, associated yeast, etc.) on microbial composition and on sourdough main features, to select the most suitable sourdough technology to be used. Highlights • Ten consecutive backsloppings, both in firm and liquid conditions, were carried out. • Lactobacilli behaviour depended on dough yield, refreshment time and associated yeast. • Maltose depletion mostly affected Lactobacillus sanfranciscensis Ls51 robustness. • Lactobacillus rossiae Lr9 was the less performing strain in all the tested conditions. • Lactobacillus farciminis Lf19 was the most competitive strain in all the conditions. [ABSTRACT FROM AUTHOR]

Traditional Greek yogurt-based salad Tzatziki is one of the most popular ready-to-eat deli salads in Greece. The objective of this study was to estimate the microbial stability of Tzatziki, with and without chemical preservatives, using a rapid method. Determination of the microbial count was carried out using the bioluminescence method (ATP) and traditional microbiological analysis, plate-counting method (CFU) in various batches of the final product of Tzatziki. The results showed that the Tzatziki salad without preservatives initially gave higher relative light units (RLU) values (79,532) than the same salad with preservatives (43,198) because the potassium sorbate and the sodium benzoate, used the in recipe, appeared to suspend the action of microorganisms. After incubation in two different substrates, MacConkey and Sabouraud, the Tzatziki salad without preservatives gave higher RLU values (9,488 and 16,176, respectively) than the salad with preservatives (12,780 and 12,005, respectively). In the two selective substrates, differences appeared between the two methods of microbial count (RLU and CFU). While RLU values were roughly at the same level, the CFU values presented significant differences (p < 0.05). It was also shown that there was a strong correlation (R² = 0.93-0.95) between bacterial counts estimated by traditional CFU and ATP methods. As expected, the dominant microbial population in Tzatziki was Lactobacillus spp., originated from yogurt. Coliforms and yeasts were not able to survive in this environment. Generally, according to the results, Greek traditional Tzatziki salad was a microbial stable product and the bioluminescence method could be a rapid method to determine its microbial state. [ABSTRACT FROM AUTHOR]

Abstract European consumers generally still have a reluctant attitude towards the consumption of insects. One strategy to trigger the willingness to consume edible insects is to process them invisibly in familiar foodstuffs. To facilitate this, insects need to be processed to intermediates that can be incorporated readily in products by the food industry. To this end, a mealworm paste that was free of tastable exoskeleton particles was manufactured successfully using industrial equipment. Of this novel intermediate the proximate and fatty acid composition, moisture content, water activity, pH, viscosity, peroxide and p -anisidine values and colour was analysed. Next, the impact of storage temperature (4 °C and −21 °C) and presence of preservatives (sodium nitrite and sodium lactate) on the chemical and microbial stability of the paste were evaluated, as well as its fermentability to assess the most suited preservation strategy. During storage at −21 °C, all tested parameters remained constant for three months, except for some fat oxidation. At 4 °C, substantial microbial growth was observed during three weeks of storage, regardless of the use of preservatives. Finally, the paste was also shown to be suited for fermentation. Future research should assess whether fermentation can extend the storage time and/or improve the product quality. Highlights • Mealworm paste without exoskeleton particles can be produced in industrial equipment. • Storage at −21 °C ensures colour, viscosity and microbial stability for 3 months. • Storage at 4 °C does not ensure microbial stability during 3 weeks of storage. • The two tested preservatives did not increase the microbial stability of the paste. • The mealworm paste can be fermented using a commercial meat starter culture. [ABSTRACT FROM AUTHOR]