Combined UV-C Technologies to Improve Safety and Quality of Fish and Meat Products: A Systematic Review.

This study aimed to identify the best UV-C combined treatments for ensuring the safety and quality of fish and meat products. A total of 4592 articles were screened in the relevant databases, and 16 were eligible studies. For fish, the most effective treatments to reduce Gram-negative and Gram-positive bacteria were UV-C at 0.5 J/cm2 + non-thermal atmospheric plasma (NTAP) for 8 min (33.83%) and 1% Verdad N6 + 0.05 J/cm2 + vacuum packaging (25.81%), respectively. An oxygen absorber with 0.102 J/cm2 was the best combined treatment, reducing lipid oxidation (65.59%), protein oxidation (48.95), color (ΔE = 4.51), and hardness changes (18.61%), in addition to a shelf-life extension of at least 2 days. For meat products, Gram-negative bacteria were more reduced by nir-infrared heating (NIR-H; 200.36 µW/cm2/nm) combined with 0.13 J/cm2 (70.82%) and 0.11 J/cm2 (52.09%). While Gram-positive bacteria by 0.13 J/cm2 with NIR-H (200.36 µW/cm2/nm), 1, 2, or 4 J/cm2 with flash pasteurization (FP) during 1.5 or 3 s, and 2 J/cm2 with FP for 0.75 s (58.89-67.77%). LAE (5%) + 0.5 J/cm2 was promising for maintaining color and texture. UV-C combined technologies seem to be a cost-effective alternative to ensure safety with little to no quality changes in fish and meat products.

Antioxidant, Antibacterial and Antibiofilm Activity of Nanoemulsion-Based Natural Compound Delivery Systems Compared with Non-Nanoemulsified Versions.

This study aimed to develop nanoemulsions with a focus on improving the bioactivity of oregano essential oil (OEO), carvacrol and thymol for possible food applications. Nanoemulsions were prepared with acoustic cavitation using ultrasound. The nanodroplets had average diameters of 54.47, 81.66 and 84.07 nm for OEO, thymol and carvacrol, respectively. The main compound in OEO was carvacrol (74%), and the concentration in the nanoemulsions was 9.46 mg/mL for OEO and the isolated compounds. The effects of droplet size reduction on antioxidant, antibacterial and antibiofilm activity were evaluated. Regarding antioxidant activity, the nanoemulsions performed better at the same concentration, with inhibitions >45% of the DPPH radical and significant differences compared with their non-nanoemulsified versions (p < 0.05). The nanoemulsions' minimum inhibitory concentration (MIC) and non-nanoemulsified compounds were evaluated against foodborne pathogens with inhibition ranges between 0.147 and 2.36 mg/mL. All evaluated pathogens were more sensitive to nanoemulsions, with reductions of up to four times in MIC compared with non-nanoemulsified versions. E. coli and S. Enteritidis were the most sensitive bacteria to the carvacrol nanoemulsion with MICs of 0.147 mg/mL. Concerning antibiofilm activity, nanoemulsions at concentrations up to four times lower than non-nanoemulsified versions showed inhibition of bacterial adhesion >67.2% and removal of adhered cells >57.7%. Overall, the observed effects indicate that droplet size reduction improved the bioactivity of OEO, carvacrol and thymol, suggesting that nanoemulsion-based delivery systems for natural compounds may be alternatives for food applications compared with free natural compounds.

Principles, Application, and Gaps of High-Intensity Ultrasound and High-Pressure Processing to Improve Meat Texture.

In this study, we evaluate the most recently applied emerging non-thermal technologies (NTT) to improve meat tenderization, high-intensity ultrasound (HIUS), and high-pressure processing (HPP), aiming to understand if individual effects are beneficial and how extrinsic and intrinsic factors influence meat toughness. We performed a systematic literature search and meta-analysis in four databases (Web of Science, Scopus, Embase, and PubMed). Among the recovered articles (n = 192), 59 studies were included. We found better sonication time in the range of 2-20 min. Muscle composition significantly influences HIUS effects, being type IIb fiber muscles more difficult to tenderize (p < 0.05). HPP effects are beneficial to tenderization at 200-250 MPa and 15-20 min, being lower and higher conditions considered inconclusive, tending to tenderization. Despite these results, undesirable physicochemical, microstructural, and sensory alterations are still unknown or represent barriers against applying NTT at the industrial level. Optimization studies and more robust analyses are suggested to enable its future implementation. Moreover, combining NTT with plant enzymes demonstrates an interesting alternative to improve the tenderization effect caused by NTT. Therefore, HIUS and HPP are promising technologies for tenderization and should be optimized considering time, intensity, pressure, muscle composition, undesirable changes, and combination with other methods.

Toxic metal and metalloid contamination in seafood from an eutrophic Brazilian estuary and associated public health risks.

Guanabara Bay (GB) is a highly contaminated estuarine system and an important fishing area in Southeastern Brazil. In this regard, knowledge concerning the association of certain contaminants in seafood to abiotic factors and human health risk assessments is still understudied. Therefore, this study aimed to quantify nine toxic elements in highly consumed crabs, shrimp, and squid, and associate the results with abiotic factors. A human health risk assessment was also performed. Our findings indicate that crabs are the main bioaccumulators. Transparency and depth were noteworthy for all three taxonomic groups. In general, contaminant concentrations were below the limits established by different international agencies, except for As, which was higher than the Brazilian limit (1 mg kg-1). However, the Hazard Index identified risks to consumer health for the ingestion of seafood. This study emphasizes the importance of jointly evaluating different toxic elements, for a more accurate health risk assessment.

Baseline titanium levels of three highly consumed invertebrates from an eutrophic estuary in southeastern Brazil.

Titanium (Ti) is considered a contaminant of emerging interest, as it displays toxic potential and has been increasingly employed in everyday products, pharmaceuticals, and food additives, mainly in nanoparticle form. However, several knowledge gaps are still noted, especially concerning its dynamics in the water. In this context, this study aimed to quantify total Ti concentrations in highly consumed swimming crabs, squid, and shrimp from an important estuary located in southeastern Brazil. Ti concentrations were higher than those reported in most studies carried out worldwide. Animal length and weight, as well as, depth, transparency, dissolved oxygen, and salinity, significantly influence Ti concentrations in the animals. Human health risks were also noted after calculating a simulated exposure to titanium dioxide, especially considering the uncertainties regarding the effects of this element and the absence of regulatory limits.

Can droplet size influence antibacterial activity in ultrasound-prepared essential oil nanoemulsions?

Essential oil nanoemulsion may have improved antibacterial properties over pure oil and can be used for food preservation. Ultrasonic cavitation is the most common mechanism for producing nanoemulsions, and the impact of processing parameters on droplet properties needs to be elucidated. A systematic literature search was performed in four databases (Science Direct, Web of Science, Scopus and PubMed), and 987 articles were found, 16 of which were eligible for the present study. A meta-analysis was performed to qualitatively assess which process parameters (power, sonication time, essential oil, and tween 80 concentration) can influence the final droplet size and polydispersity and how droplet size is associated with antibacterial activity. We observed that power, essential oil, and tween 80 concentrations added during processing are the critical variables for forming smaller droplets. Ratios of up to 3:1 (surfactant:oil) can produce droplets smaller than 180 nm with antibacterial properties superior to pure oil or isolated compounds. The improved properties of nanoemulsions are associated with the size and chemical composition of the droplet since the proportion of the hydrophobic core (EO) and the hydrophilic outer layer (Tween 80) directly influences the antibacterial mechanism of action.

Interactions between mercury and environmental factors: A chemometric assessment in seafood from an eutrophic estuary in southeastern Brazil.

Guanabara Bay (GB) is an estuary in Brazil, constantly the target of pollutants, such as mercury (Hg). Thus, our study aimed to evaluate (i) total mercury (THg) content in shrimp and squid species from GB; (ii) associate THg content to contamination in swimming crabs; (iii) explore potential differences between species, and size; (iv) correlate abiotic water data to the determined THg contents; (v) verify if Hg concentrations are below acceptable limits. Swimming crabs showed greater Hg contamination compared to other species. For shrimp only biometric variables are related to Hg, while for squid, only abiotic. Only squids did not show a correlation between Hg and animal size. Finally, the detected Hg values are below the tolerable limits established by legislations. Our results indicate that the dynamics of Hg contamination differs between groups and that further studies are needed to elucidate the mechanisms that affect bioaccumulation in different species.

Inactivation of Multi-Drug Resistant Non-Typhoidal Salmonella and Wild-Type Escherichia coli STEC Using Organic Acids: A Potential Alternative to the Food Industry.

Salmonella and Escherichia coli are the main bacterial species involved in food outbreaks worldwide. Recent reports showed that chemical sanitizers commonly used to control these pathogens could induce antibiotic resistance. Therefore, this study aimed to describe the efficiency of chemical sanitizers and organic acids when inactivating wild and clinical strains of Salmonella and E. coli, targeting a 4-log reduction. To achieve this goal, three methods were applied. (i) Disk-diffusion challenge for organic acids. (ii) Determination of MIC for two acids (acetic and lactic), as well as two sanitizers (quaternary compound and sodium hypochlorite). (iii) The development of inactivation models from the previously defined concentrations. In disk-diffusion, the results indicated that wild strains have higher resistance potential when compared to clinical strains. Regarding the models, quaternary ammonium and lactic acid showed a linear pattern of inactivation, while sodium hypochlorite had a linear pattern with tail dispersion, and acetic acid has Weibull dispersion to E. coli. The concentration to 4-log reduction differed from Salmonella and E. coli in acetic acid and sodium hypochlorite. The use of organic acids is an alternative method for antimicrobial control. Our study indicates the levels of organic acids and sanitizers to be used in the inactivation of emerging foodborne pathogens.

Salmonella enterica: A hidden risk for dry-cured meat consumption?

Meat curing, fermentation, and drying are both preservation technologies, and traditional manufacturing practices. Despite being considered a safe food, due to the several hurdles that prevent pathogen growth, dry-cured meat manufacturing may not ensure complete pathogen elimination. Besides, the final products are still susceptible to microbial contamination. Salmonella enterica is noteworthy among the pathogenic microorganisms that can contaminate these products. To survive hypertonic/hyperosmotic, acid, and low aw/desiccation stresses intrinsically associated with dry-curing, Salmonella has evolved with highly sophisticated mechanisms, comprising sensors/receptors, signaling cascade systems, and enzymes/transcription factors that ensure their tolerance and survival despite many harsh environmental conditions. Links between osmotic and acid stresses, such as the dissociable sigma factor of RNA polymerase, which regulates gene transcription, and mutual membrane receptors like the two-component system EnvZ/OmpR, which senses abiotic conditions, lead to stress cross-protection. Furthermore, virulence gene expression seems to be triggered by sublethal stresses on pre-adapted Salmonella cells, increasing their adherence and invasiveness of host cells. These are evidence that the ability to tolerate stresses enhances Salmonella pathogenicity and compromises the safety of dry-cured meats, by sheltering the pre-exposed and, subsequently, more virulent, stressed bacterial cells.

Caracterização sensorial e análises físico-químicas de diferentes espécies de peixes durante armazenamento a 0°C / Sensorial description and physicochemical analyzes of different species of fishes during 0°C storage

O consumo de peixe vem aumentando devido aos seus benefícios nutricionais. No entanto, é um produto altamente perecível devido à sua composição. O objetivo do trabalho foi avaliar o comportamento sensorial e físico-químico de três espécies de peixe: xixarro (Trachurus lathami), olho de cão (Priacanthus arenatus) e corvina (Micropogonias furnieri), durante o período de 11 dias de estocagem. Foram realizadas a caracterização sensorial e análises de cocção, pH, amônia, gás sulfídrico e bases voláteis totais. O pH e as bases voláteis totais não apresentaram resultados superiores aos da legislação. A caracterização sensorial indicou que o xixarro sofreu alterações sensoriais mais rapidamente que as outras espécies e as análises físico-químicas feitas não foram suficientes para detectar os primeiros estágios da deterioração.

Influência do ultrassom no crescimento de Salmonella typhimurium / Influence of ultrasound in Salmonella typhimurium growth

O ultrassom tem sido amplamente estudado na inativação de microrganismos e no processamento de alimentos. Entretanto, o efeito sobre o crescimento de bactérias ainda é pouco elucidado. O presente estudo avaliou o efeito de diferentes densidades energéticas de ultrassom (0; 0,11; 0,22 e 0,43 KJ/mL) no crescimento de Salmonella enterica serovar Typhimurium em caldo BHI. Altas densidades energéticas diminuíram (p < 0,05) a duração da fase lag e a densidade de células na fase estacionária. Entretanto, não houve diferença (p < 0,05) na velocidade de crescimento. Portanto, os resultados do presente estudo alertam para os riscos do ultrassom quando aplicado isoladamente. Assim, as aplicações desta tecnologia, isoladamente, em alimentos que suportam o crescimento de patógenos, como carne e produtos cárneos, devem ser minuciosamente avaliadas para cada tipo de produto.

Combination of peracetic acid and ultrasound reduces Salmonella Typhimurium on fresh lettuce (Lactuca sativa L. var. crispa).

Salmonella outbreaks related to fruits and vegetables have been reported being lettuce one of the most contaminated. Peracetic acid (PA) at 50 mg/L, sodium dichloroisocyanurate (SD) at 100 mg/L, and the combination of SD at 100 mg/L and babaçu coconut (Attalea speciosa) oil detergent at 100 mg/L were applied to fresh lettuce. Natural contaminant microbiota, physicochemical characteristics, and sensory attributes were evaluated. PA and SD reduced mesophilic aerobic counts by 2.1 and 1.5 log cfu/g, respectively. The most efficient treatment in reducing natural microbiota (i.e., PA) was applied alone and in combination with ultrasound (US). It reduced Salmonella enterica Typhimurium counts to undetectable levels (< 1 log cfu/g). US further reduced S. Typhimurium counts by 0.6 log cfu/g in relation to PA, treatment which lessened the pH but increased the titratable acidity of lettuce, but did not cause total color difference. Therefore, the combination of PA and US holds a potential industrial application for sanitization purposes.

Ultrasound improves antimicrobial effect of sodium dichloroisocyanurate to reduce Salmonella Typhimurium on purple cabbage.

The consumer's interest in ready-to-eat, fast-ready, nutritious and fresh foods is a major challenge for the food industry. Thus, studies on new sanitization methods are relevant. The effect of Sodium Hypochlorite (SH), Benzalkonium Chloride (BC), and Sodium Dichloroisocyanurate (SD) isolated or combined with Ultrasound (US) in purple cabbage quality over 7 days of storage at 8 ±â€¯1 °C was evaluated. The natural microbiota (mesophilic aerobic bacteria, lactic acid bacteria and coliforms), intentionally inoculated Salmonella Typhimurium, physicochemical quality (anthocyanins, pH, total titratable acidity, instrumental color and mass loss) and sensorial quality (multiple comparison test and visual sensory acceptance) were analyzed. The best treatments for natural microbiota reduction were BC and US + BC, which in general reduced between 1.9 and 3.2 log cfu/g. US improved (p < .05) the effect of SD reducing almost 4 log cycles in the population of S. Typhimurium adhered to cabbage. The treatments with benzalkonium chloride resulted in important physicochemical changes in cabbage. The treatments SD and US + SD did not alter the physicochemical and sensorial characteristics of purple cabbage. Therefore, ultrasound combined with sodium dichloroisocyanurate is a promising alternative for the reduction of microbiological contaminants of purple cabbage without physicochemical, sensory and anthocyanin content loss.

Ultrasound improves chemical reduction of natural contaminant microbiota and Salmonella enterica subsp. enterica on strawberries.

New sanitization methods have been evaluated to improve food safety and food quality and to replace chlorine compounds. However, these new methods can lead to physicochemical and sensory changes in fruits and vegetables. The present study evaluated the effects of acetic acid, peracetic acid, and sodium dodecylbenzenesulfonate isolated or combined with 5min of ultrasound treatment (40kHz, 500W) on strawberry quality over 9days of storage at 8°C. The strawberry natural contaminant microbiota (molds and yeasts, mesophilic aerobic and lactic acid bacteria), physicochemical quality (pH, total titratable acidity, total soluble solids, vitamin C, and color), sensory quality (triangle test) and inactivation of Salmonella enterica subsp. enterica intentionally inoculated onto strawberries were analyzed. Ultrasound increased the effect of all chemical compounds in the reduction of aerobic mesophilic, molds and yeasts. The best treatment for those groups of microorganisms was ultrasound combined with peracetic acid (US+PA) that reduced 1.8 and 2.0logcfu/g during 9days of storage. Bactericidal effect of peracetic acid was also improved by ultrasound inactivation of S. enterica, reaching a decimal reduction of 2.1logcfu/g. Moreover, synergistic effects were observed in contaminant natural microbiota inactivation for all tested compounds during storage, without any major physicochemical or sensory alteration to the strawberries. Therefore, ultrasound treatment can improve the effect of sanitizers that are substitutes of chlorine compounds without altering the quality of strawberries during storage. Acetic acid (PubChem CID: 176); Peracetic acid (PubChem CID: 6585); Sodium dodecylbenzenesulfonate (PubChem CID: 18372154).