Aerobic Bacteria Counts Research Articles

Effect of dietary β‐glucan supplementation on growth performance, body composition, intestinal microbes, and capacity against pathogen of golden trevally (Gnathanodon speciosus, family Carangidae)

AbstractThe efficacy of dietary β‐glucan supplementation in golden trevally (Gnathanodon speciosus) was evaluated. The fish were fed five different diets supplemented with 0%, 0.05%, 0.10%, 0.20%, and 0.40% β‐glucan for 56 days. After 56 days of culture, survival was the highest when the fish were fed a 0.10% β‐glucan diet. Growth rates were higher in fish fed diets supplemented with all β‐glucan levels. Lymphocytes increased when the fish were fed a diet supplemented with 0.05% β‐glucan, and thrombocytes increased when the fish were fed 0.2% and 0.4% β‐glucan‐supplemented diets. The total aerobic bacteria count in the gut of golden trevally was higher (p < 0.05) and the total Vibrio counts in the gut of golden trevally were lower (p < 0.05) when the fish were fed any level of β‐glucan. Flesh protein content was higher and flesh lipid content was lower when fish were fed β‐glucan‐supplemented diets at levels greater than 0.1%. When challenged with Streptococcus iniae, fish fed diets containing 0.10% or 0.20% β‐glucan exhibited the highest survival rates. The current results suggest that supplementation with 0.05 to 0.2% β‐glucan in the diet would be beneficial for the culture of the golden trevally.

Innovative texture-improving fermented sausages prepared by refining waste seawater: Physicochemical and histological properties

This study aimed to investigate how the addition of sea-brine and -bittern obtained from waste seawater affects fermented sausage's physicochemical and histological properties from 1st to 5th week. The pH and water activity were higher in the samples containing sea-brine and -bittern (TR and TT) compared to the controls (CP and CN), while the dry yield was lower in CP (P < 0.05). This result was shown because the salt-soluble protein was easily formed by the dissociated salt. The higher lactic acid and aerobic bacteria count were observed in the BR and BT than in the controls at weeks 3, 4, and 5 (P < 0.05). Furthermore, the excellent emulsifying power (emulsion capacity and viscosity) observed in the BT may be attributed to the inorganic salts contained in the sea-bittern. Overall, the study concludes that adding seawater to fermented sausages is a promising strategy to improve their texture and other properties.

Effect of electron beam irradiation on minas frescal cheese artificially contaminated with Shiga toxin-producing Escherichia coli O157:H7

Minas frescal cheese (MFC) is a potential vehicle for Shiga toxin-producing Escherichia coli (STEC) O157:H7. The effect of electron beam irradiation on the control of STEC O157:H7 in artificially contaminated MFC (5 log cfu g−1) was evaluated. Samples were irradiated at doses of 1.0, 1.5, and 2.0 kGy and evaluated for 40 days at 4 °C. Shelf life extension and the stability of the lipid fraction of the cheeses were also evaluated. At a dose of 1.0 kGy, STEC O157:H7 was reduced by 3 log cfu g−1, while at 1.5 and 2.0 kGy, STEC O157:H7 was eliminated. Shelf life extension, measured by the count of total aerobic bacteria (TAB), occurred in up to ten days. Irradiated and non-irradiated samples were affected by lipid oxidation. Electron beam irradiation proved to be a viable technology and a good alternative to guarantee the quality and control of STEC O157:H7 in the MFC.

Evaluation of the combined effects of sodium chloride, potassium sorbate, citric acid, vacuum packaging and refrigerated storage on shelf‐life extension of desalted hake

SummaryIn this comprehensive investigation, we examined the impact of incorporating sodium chloride, potassium sorbate and citric acid, during the desalting stage to extend the shelf life of desalted hake (Merluccius hubbsi). Compared to the conventional desalting carried out in water, the desalting with the additive assayed significantly reduced total aerobic bacteria counts and extended the shelf life by threefold (from 5.7 to 21.7 days at 4 °C). After 42 days of storage in vacuum packaging, the desalted with additives hake samples showed low levels of volatile nitrogenous compounds and malondialdehyde (MDA) concentration (21.78 ± 0.56 mg TBVN 100 g−1 and 0.531 ± 0.015 mg MDA kg−1, respectively). Mechanical and colour parameters remained stable, and sensory characteristics (smell, appearance, texture, taste) did not change for 28 days at 4 °C. These findings demonstrate that the incorporation of additives into a meticulously designed three‐stage desalting process enables the production of a ready‐to‐use fishery product with an extended market life under refrigeration.

Tracking Microbial Diversity and Hygienic-Sanitary Status during Processing of Farmed Rainbow Trout (Oncorhynchus mykiss).

Aquaculture is becoming a strategic sector for many national economies to supply the increasing demand for fish from consumers. Fish culture conditions and processing operations can lead to an increase in microbial contamination of farmed fish that may shorten the shelf-life of fish products and byproducts, and ready-to-eat fishery products. The objective of this study was to evaluate the hygienic-sanitary status of water, environment, and processing of fresh-farmed rainbow trout (Oncorhynchus mykiss) fillets produced in a local fish farm in Andalusia, Spain. To achieve this, a longitudinal study was carried out by collecting environmental (air and food-contact surfaces), water from fish ponds, and rainbow trout samples. Thereby, seven sampling visits were performed between February 2021 and July 2022, where foodborne pathogens and spoilage microorganisms, together with physicochemical parameters, were analysed in the collected samples. Further, microbial identification of microbiota was achieved through a culture-dependent technique using blast analysis of 16S RNA gene sequencing. The results showed that Listeria monocytogenes and Salmonella were not detected in the analysed samples. Regarding the hygienic-sanitary status of the fish farm, the slaughtering bath, the eviscerating machine and the outlet water from fish ponds presented the highest counts of coliforms, Enterobacteriaceae, and Aerobic Mesophilic Bacteria. Staphylococcus aureus and sulphite-reducing Clostridium were identified in the conveyor belts, fish flesh, and viscera. The 16S RNA identification confirmed the presence of viable spoilage bacteria such as Citrobacter gillenii, Macrococcus caseolyticus, Hafnia paralvei, Lactococcus lactis, Lactococcus cremoris, Klebsiella, Escherichia coli, Morganella morganii, and Shewanella. Three of these genera (Citrobacter, Hafnia, and Pseudomonas) were present in all types of samples analysed. The results evidenced potential transmission of microbial contamination from contaminated packaging belts and boxes, evisceration and filleting machines to flesh and viscera samples, thus the establishment of control measures should be implemented in fish farm facilities to extend the shelf-life of farmed fishery products.

Raspberry (Rubus idaeus L.) waste-derived nanocellulose for circular application in edible films and coatings

Due to the overuse of petroleum-derived polymers and the consumer demand for nutritious and healthy products that can maintain their quality over longer periods of time, there is a need for new sustainable packaging systems that fulfill these requirements. Lignocellulosic biomass, particularly agricultural pruning residues, offer great potential for obtaining biopolymers through biorefining processes. In this study, raspberry pruning residues were used to produce lignocellulose nanofibers (LCNF) and cellulose nanofibers (CNF), by varying the intensity of TEMPO-mediated oxidation pretreatment (5 and 10 mmol/g) and examining the amount of residual lignin and its impact on reinforcement capacity in food edible films and coating using chitosan-based formulations. The addition of CNF/LCNF up to 0.05 g/g of film, improved the mechanical properties of films, with Tensile Strength (TS) reaching a highest value of 40.98 MPa for 0.03 g/g LCNF-TO5 films. The presence of residual lignin in LCNF enhanced the optical properties of the films, particularly in terms of UV light blocking, with values of 84.56% achieved for 0.15 g/g LCNF-TO5 samples. The use of a coating with concentrations of up to 0.1 g/g LCNF resulted in improved firmness values and lower counts of aerobic mesophilic bacteria (AMB) after 7 days of storage.

Transglutaminase induced whey cheese production: impact of different ratios on yield, texture, and sensory properties

The yield of whey cheese production is often low, and its texture is often soft. Therefore, this study investigated the effects of different ratios (2 U/g protein and 5 U/g protein) of microbial transglutaminase (mTG) on composition (dry matter, ash, protein, and fat), yield, and acidity (pH and lactic acid), microbiological properties (Lactococcus, Lactobacillus and total aerobic mesophilic bacteria counts), texture profile, electrophoretic properties (SDS-PAGE) and sensory properties (appearance, texture and taste) of whey cheese. The samples with 2 U/g protein mTG had better properties in terms of yield, hardness and sensory values. The results from SDS-PAGE also showed that the sample with 2 U/g protein mTG had more cross-linking than the sample with 5 U/g protein mTG. In comparison, the sample with 5 U/g protein mTG had a lower number of lactic acid bacteria and poor sensory characteristics. These results indicate that the addition of mTG in an appropriate amount (2 U/g protein) can improve the yield, texture profile, and sensory properties of whey cheese, while excessive addition of mTG can negatively affect these properties.

Effect of sprayed different concentrations of Moringa oleifera leaves extract on broiler breeder hatching eggs

This research aimed to study the impact of spraying different Concentrations of Moringa oleifera leaves Extract on Broiler Breeder Hatching Eggs. The results cleared that, at 18th day the egg weight ranged from 60.50 in the group treated with 5 % M. Water extract to 62.16 gm in control group. While, the egg losses observed in group 4 that, treated with 2 % M. water extract that was 20.56 % at 21st day. The higher hatchability % of total eggs showed in control group that was 69.70 %. While, the hatchability % of fertile eggs showed a higher percentage in group 5 that treated with 5 % M. Water extract that was 99.02 %. The higher percentage of dead embryo observed in control group that was 9.10 % and the lower level observed in the group 2 that treated with 2 % M. Alchole exteract that was 5.46 %. The total aerobic bacteria counts at 18th day of incubation showed a lower level in group 5 that treated with 5 % M. water extract that was 7.88. while, the activity of chicks and in abnormal chicks increased in group that treated with 5% M. Water extract that was 8.96 % and 2 % respectively. Overall, the higher concentration of Alchole extract of M. olifera , increased the weight of hatching eggs with a reduction in total egg losses,% of the eggs. While, the higher concentration of the water extract of M. olifera improved the hatchability % a reduction in total aerobic counts on the egg shell and improved chick quality and activity.

Çaça (Sprattus sprattus, L., 1758) Protein Hidrolizatının Fizikokimyasal Özellikleri ve Alabalık (Oncorhynchus mykiss, Walbaum, 1792) Filetolarında Kaplama Malzemesi Olarak Kullanımı

Trout is the most widely cultivated and traded fish species in Turkey and many European countries, and a total of 471686 tons of production was realized in Turkey’s seas and inland waters in 2021. In addition to its nutritive value, this fish takes a crucial position in the aquaculture sector due to its continuous and intensive production. In this study, innovative bioactive protein hydrolysates (PH) produced from sprat were used as a coating to increase the quality and shelf life of trout fillets stored at +4 ˚C. The yields of traditional hydrolysate (TH) and ultrasound-assisted hydrolysate (UH) were 8.66% and 12.63%, respectively. Protein values of TH and UH were 75.88 and 74.45%, respectively. Three fillet groups were prepared from trout: uncoated control group (C), traditional enzymatic protein hydrolysate coated group (THC), and ultrasound-assisted enzymatic protein hydrolysate coated group (UHC). TVB-N value, which was 12.96 mg/100g in fresh trout, exceeded the consumable limit with 38.52 mg/100g on the 9th day of storage in the C. This value reached 32.92 mg/100g and 33.62 mg/100g on the 12th day for THC and UHC, respectively. At the beginning of storage, 0.21 mg MA/kg TBA reached the consumable limit with 7.72 mg MA/kg in the C on the 9th day, while THC and UHC remained within the limit with 6.67 mg MA/kg and 6.79 mg MA/kg, respectively. Total aerobic mesophilic bacteria (TAMB) and total aerobic psychrophilic bacteria (TAPB) counts on day 0 of storage were 2.13 log cfu/g and 1.66 log cfu/g, respectively. These values were calculated as 6.90, 5.20, 5.04, 6.95, 3.48, and 3.22 log cfu/g for C, THC, and UHC on the 12th day of storage, respectively. The application of ultrasound during the production of protein hydrolysate significantly increased the yield and hydrolysis degree of UH compared to TH. The lipid ratio of UH was also found to be significantly lower than TH. In these respects, the application of ultrasound has provided an advantage. Although both coatings have provided significant protection compared to the C, generally similar results were obtained between the THC and UHC. PH coatings delayed the chemical, physical, and microbial spoilage of trout fillets and extended the storage period. The results showed that PH can be used as a coating on fish fillets stored in cold conditions.

Street-vended grilled beef sausages as potential vehicles of bacterial and fungal pathogens: An exploratory survey in Ho, the capital city of the Volta Region of Ghana.

Grilled beef sausage is a popular street delicacy in many countries, and Ghana is no exception. This study assessed street-vended grilled beef sausages as a potential vehicle of microorganisms that present food safety risks to the general public in Ho City. Twenty grilled beef sausages were obtained from various vended locations within Ho municipality by convenient sampling and were analyzed by standard microbiological protocols for food safety followed by statistical analysis with a test of significant difference at p < .05. Total aerobic bacteria count of the potential foodborne pathogens ranged from 2.75 × 104 to 1.85 × 107 CFU/g. The microbial species identified included Staphylococcus aureus with a load from 6.15 × 102 to 1.67 × 105 CFU/g, Escherichia coli from 4.2 × 102 to 3.9 × 104 CFU/g, Bacillus cereus from 3.05 × 102 to 7.1 × 104 CFU/g, and Salmonella spp. from 2.8 × 102 to 5.5 × 104 CFU/g. Total fungal counts also ranged from 0.0 to 9.83 × 103 CFU/g, and the species identified included Aspergillus spp. and Rhizopus spp. all of which were within the acceptable limits of the International Commission for Microbiological Specification of Foods. However, for total viable bacteria, 75% of the samples were above the acceptable limits in the guidelines by the Ghana Standards Authority, indicating that the consumption of grilled beef sausages poses serious food safety and hygiene risks to consumers. Hygienic processing of the sausages under sanitary environments, proper handling and preservation procedures, and periodic follow-up visits to the vended areas should be employed to reduce the risk of occurrence of potential pathogens in the products.

Long‐term monitoring of the microbial quality and Legionnaires' disease risk in tap water from mass catering establishments

AbstractLegionnaires' disease is caused by Legionella (L.) pneumophila. Inhaling aerosolized water containing this bacteria is the most common transmission route. Shower heads used in the catering industry's dishwashing units are also potential amplifying systems for bacteria and possible sources of infection by generating droplets and aerosols. Therefore, these systems should not contain pathogenic bacteria. This study aims to monitor the microbial quality, Legionnaires' disease risk and L. pneumophila presence in tap water samples from the water outlet of the shower‐type dishwashing unit of mass catering establishments for a year. Seventy‐two tap water samples were microbiologically tested for total mesophilic aerobic bacteria count, coliform, Escherichia (E.) coli and L. pneumophila. DNA was isolated from L. pneumophila‐positive samples, and their serogroup was characterized by real‐time PCR. The correlation between seasonal variation and prevalence of L. pneumophila serogroup and L. pneumophila and other indicator bacteria were statistically tested by Spearman rank test (p &lt; 0.05). Findings showed that 17 (24%) samples had microbial growth, 14 (19.4%) were positive for L. pneumophila and 13 isolates were characterized as L. pneumophila serogroup 1. The statistical analysis showed no significant correlation between seasonal variation (p = 0.491) and L. pneumophila and total mesophilic aerobic bacteria count, coliform and E. coli (p = 0.923). Overall, Legionella spp. is an essential indicator of the microbial quality in the tap water from mass catering establishments and should be regularly monitored for public health independently from seasonal variation and other indicator bacteria.

Toxicity of Diphenyltin Chloride on viable count of aerobic bacteria from River Benue.

This research was carried out to determine the toxicity of diphenyltin chloride on viable count of freshwater aerobic bacteria. Water samples obtained from a depth of 15 cm at five sampling points along river Benue were spiked with 3 mM of DPTCl to have a duplicate setup of three (3) treatments. Organotin degradation was determined by measuring the decrease in the concentration of DPTCl using an X-ray fluorescence spectrophotometer on days 0, 14, 28, 42, and 56 and the viable count of bacteria was also determined using spread plate technique on MSA. DPTCl concentration was further varied (5 mM, 7 mM and 10 mM) to test levels of toxicity to viable count of bacteria as well as bacterial resistance. patio sequencing technique was used to determine the metagenomics of bacteria species capable of DPTCl degradation from the water samples. Percentage of chemically degraded (40.29%) during the initial two weeks of experiment when the bacterial population was high, was more than the percentage degraded (11.49%) during the last two weeks of the experiment when the biocidal effect of DPTCl had drastically reduced the bacterial population. Of the initial bacterial viable count of 47.2 x 102 that survived the 56 days degradation exercise, only 1.8x101 (0.38%) grew on 7 mM concentration of DPTCl, and none on 10 mM DPTCl. The impact of DPTCl on the viable count of bacteria was statistically significant. Stenotrophomonas spp (29.6%) was the dominant bacterium in DPT degradation, others include; Comamonas spp (9.31%), Microbacterium spp (8.41%) Pseudomonas viridiflava (4.18%), and Stenotrophomonas geniculata (3.46%). Organotins. Diphenyltin though a di-alkyl organotin, is equally a toxic and persistent pollutant that cannot be easily degraded without the use of nutrient amendment. The toxic effect of DPT as demonstrated in this study shows that TPT and other tri-alkyl organotin should not be considered detoxified especially against microorganisms simply because they have been de-alkylated.Sites contaminated by organotins should not be considered remediated until all di and mono alkyl derivatives are completely degraded. Since our natural environments usually have no sufficient nutrient amendments for elimination of pollutants, there is need to engage abiotic processes that can assist the activities of microorganisms in order to speed up remediation process.

Dynamics associated with fermentation and aerobic deterioration of high-moisture Italian ryegrass silage made using Lactobacillus plantarum and caproic acid.

To determine the fermentation quality, aerobic stability, and chemical composition of Italian ryegrass silage prepared with Lactobacillus plantarum (LP), caproic acid (CA), and their combination during ensiling and feed-out phase. Six treatments: control (CON), LP, 0.15% caproic acid (LCA), 0.2% caproic acid (HCA), LCA+LP, and HCA+LP were employed for 30 days ensiling and an 8-days aerobic stability test. LP had similar pH value and lactic acid content with LCA+LP, while the contents of NH3-N and total VFAs in LCA+LP were significantly lower than those in LP and CON, and the fermentation quality of LCA+LP performed best among all silages. As air-exposure extended, contents of water-soluble carbohydrates (WSC), lactic, and acetic acids decreased, while pH, and NH3-N content increased significantly. The population of lactic acid bacteria gradually decreased in contrast to increased counts of aerobic bacteria and yeasts. Compared with LCA, 0.2% CA delayed the aerobic deterioration as judged by a slower increase in pH and high residual of WSC and lactic acid, and negligible ethanol content and anaerobe spores counts remained in HCA at the end of air exposure. Compared with CON (73 h), LP showed less aerobic stability (38 h), whereas HCA and HCA+LP prolonged aerobic stability for 210 and 152 h, better than LCA (109 h) and LCA+LP (146 h). Lactobacillus plantarum apparently improved the fermentation quality, and combined with CA exhibited greater efficiency in inhibiting undesirable microorganism during ensiling. CA at 0.2% optimally extended the aerobic stability.

Effect of Aloe vera and carboxymethyl cellulose-derived binary blend edible coating on the shelf life of fresh-cut apple.

In recent years, the demand and market for minimally processed fruits are increasing worldwide. Fresh-cut apples are extremely sensitive to environmental factors including oxygen, temperature, and microorganisms in resulting the browning of apples. Therefore, in this study, different concentration of blended edible-coating solution was prepared using Aloe vera and carboxymethyl cellulose (1:1, 1:2, 2:1, 3:3, 3:2, 4:2, 2:4, 3:4, and 4:3, respectively). Lease particle size (101.74 ± 0.67 nm) of the coating solution was observed with 3% A. vera and 2% carboxymethyl cellulose (CMC). Afterward, the shelf life of the apples was evaluated for 10 days at refrigeration condition. Results showed that a significant difference was found in weight loss of coated (6.42%-10.26%) and uncoated apples (8.12%-15.32%) for 2-10 days. Moreover, the titrable acidity of the cut apples increased during the storage time. Rheological data emerged that the viscosity of the coating solution decreases with the increasing temperature from 0 to 50°C. Fourier transform infrared spectroscopy data confirmed the presence of hydroxyl group (-OH), C=O, C-O, and N-H banding in the A. vera, CMC, and blend-coating solution. The blend solution indicated excellent antimicrobial efficiency. Total phenolic content of coated and uncoated apples at 0 day was 737.55 mg GAE kg-1 for uncoated and 717.88 mg GAE kg-1, respectively. Whereas, aerobic and psychrotrophic bacteria counts for edible coated apples significantly lower than control apples. For coated apples, aerobic and psychrotrophic bacteria counts were 1.59 ± 0.84 and 1.25 ± 0.49 log CFU g-1 were 4.26 ± 0.67 and 2.68 ± 0.22 log CFU g-1 at 10th day, respectively. Overall, it can be inferred that blend of A. vera and carboxymethyl cellulose could be used as a nontoxic potential anti-browning and antimicrobial component for the enhancement of the shelf life and additional nutritional value of fresh-cut apples.

Prevalence of bacterial isolates from cell phone surfaces in Madonna University Elele Campus

Cell phones is a major revolution in the communication industry. In recent times, cell phone is carried by almost everybody, however, in some areas where not everyone has a cell phone, people patronize paid phone booths to communicate with loved ones. Madonna University, Elele Campus, is in Rivers State Nigeria and accommodates the University where all the students and staff are living on campus, The Madonna University Teaching Hospital, the pilgrimage center where pilgrims from all over the world visit regularly. There are phone booths at strategic locations where individuals pay and use their phone. Since different people use the same phone with their hands and mouth to make calls, this research was aimed at accessing the prevalence of bacteria isolates from cell phone surfaces in Madonna University, Elele campus, and the susceptibility of these organisms to commonly used antibiotics. Fifty swab samples were collected from the surface of cell phones at various locations in Madonna University, Elele Campus, and were microbiologically analyzed for the aerobic bacteria count and susceptibility to different antibiotics using the pour-plate method. Madonna University Teaching Hospital phone booth recorded the highest total aerobic bacterial count and number of bacteria isolates compared to other centers. Staphylococcus species was significantly (p&lt;0.05) the most prevalent bacteria species isolated on the cell phones, and the percentage occurrence of various isolates were: Staphylococcus species (59.5%), Salmonella species (19.1%), Streptococcus specie (9.5%) Psuedomonas species (3.1%) and Escherichia coli (2.1%). Among the gram-negative bacteria, Escherichia coli had 100% susceptibility against all the antibiotics, Salmonella species recorded 100% susceptibility against ciprofloxacin, nalidixic acid, gentamycin, chloramphenicol and ampicillin while Proteus species had 100% against streptomycin and chloramphenicol. For the gram-positive, Streptococcus species and Staphylococcus species recorded a significant percentage of susceptibility ranging from 62.5% to 100% against some of the antibiotics used. This study conclude that cell phone surfaces could be a reservoir for different disease causing micro-organism and users should take precaution against bacterial infection while using cell phone.

Effect of high pressure processing on traditional Turkish meatballs properties and microbiological safety during frozen storage

In this study, physical, chemical, and microbiological properties of high-pressurized Inegol meatballs (at 4 °C, for 10 min at 100, 200, 400, and 600 MPa) were investigated during frozen storage for 11 months. Water content, cooking loss, pH, protein solubility, SDS-PAGE, color parameters, textural and microbiological parameters were evaluated in both raw and cooked samples. Application of high pressure at 400–600 MPa had significant effects on protein solubility of the samples and these results corresponded with the SDS-PAGE. The pH of the samples increased as pressure levels increased. It was observed that ΔE and L* values of raw samples increased and a* and b* values decreased slightly as a result of the high pressure treatment. Aerobic bacteria count decreased significantly after the high pressure processing with increasing pressure levels, and that remained high throughout the storage period.

Antimicrobial Coating Based on Tahiti Lemon Essential Oil and Green Banana Flour to Preserve the Internal Quality of Quail Eggs.

This study evaluated the microbiological and internal quality of quail eggs stored for 21 days at room temperature (29.53 ± 1.36 °C) after being coated with green banana flour and Tahiti lemon essential oil (GBF/TAH). One hundred and sixty-two quail eggs were equally distributed into three treatments: (1) uncoated eggs, (2) eggs coated with green banana flour (GBF), and (3) eggs coated with GBF/TAH. The Haugh unit (HU) of the eggs was significantly lower in the third week for uncoated eggs (70.94 ± 1.63, grade A) compared to eggs coated with GBF/TAH (81.47 ± 2.38, grade AA). On the 21st day of storage, the eggs coated with GBF/TAH had significantly lower total counts of aerobic mesophilic bacteria in the shell and egg contents compared to the other treatments. GBF/TAH coating is an effective blending approach to reduce the microbial load of the shell and egg contents and preserve the sensory and internal quality of the eggs.

Effects of Plasma-Activated Water Treatment on the Inactivation of Microorganisms Present on Cherry Tomatoes and in Used Wash Solution.

Herein, we investigated the potential of plasma-activated water (PAW) as a wash solution for the microbial decontamination of cherry tomatoes. We analyzed the efficacy of PAW as a bactericidal agent based on reactive species and pH. Immersion for 5 min in PAW15 (generated via plasma activation for 15 min) was determined as optimal for microbial decontamination of fresh produce. The decontamination efficacy of PAW15 exceeded those of mimic solutions with equivalent reactive species concentrations and pH (3.0 vs. 1.7 log reduction), suggesting that the entire range of plasma-derived reactive species participates in decontamination rather than a few reactive species. PAW15-washing treatment achieved reductions of 6.89 ± 0.36, 7.49 ± 0.40, and 5.60 ± 0.05 log10 CFU/g in the counts of Bacillus cereus, Salmonella sp., and Escherichia coli O157:H7, respectively, inoculated on the surface of cherry tomatoes, with none of these strains detected in the wash solution. During 6 days of 25 °C storage post-washing, the counts of aerobic bacteria, yeasts, and molds were below the detection limit. However, PAW15 did not significantly affect the viability of RAW264.7 cells. These results demonstrate that PAW effectively inactivates microbes and foodborne pathogens on the surface of cherry tomatoes and in the wash solution. Thus, PAW could be used as an alternative wash solution in the fresh produce industry without cross-contamination during washing and environmental contamination by foodborne pathogens or potential risks to human health.

Rice flour coating supplemented with rosemary essential oil to preserve the internal, microbiological, and sensory quality of quail eggs

AbstractCoatings of rice flour (RF), reinforced or not with rosemary essential oil (ROS), were used to evaluate changes in the internal quality of quail eggs stored at room temperature. Quality parameters [egg weight loss (EWL, %), Haugh unit (HU), yolk index (YI), albumen and yolk pH], microbiological (counts of total aerobic mesophilic bacteria and Enterobacteriaceae) and sensory (colour, aroma, odour, texture, taste, and general acceptability) parameters were evaluated during the experiment. Compared to the number of total aerobic mesophilic bacteria on the shell of uncoated eggs (2.02 ± 0.49; 1.78 ± 0.20 log10 CFU mL−1), RF/ROS exhibited significant inhibition effects for these bacteria on 0. (1.16 ± 0.25 log10 CFU mL−1) and 21. (0.84 ± 0.11 log10 CFU mL−1) days of storage at room temperature. On days 7, 14, and 21, RF had no effect on HU (P &gt; 0.05), but eggs coated with RF/ROS had significantly higher HU (P &lt; 0.05) than uncoated eggs from day 14, maintaining grade AA (73.88 ± 2.67) on day 21, while uncoated eggs had grade A (68.90 ± 1.55) at that time. The RF coating reinforced with ROS was a bioactive, efficient, and safe formulation for application based on internal quality, microbiological and sensorial aspects of quail eggs.

In Vitro Rumen Fermentation of Coconut, Sugar Palm, and Durian Peel Silages, Prepared with Selected Additives

Understanding the nutritive values of fruit peel residues could expand our feed atlas in sustaining livestock production systems. This study aimed to investigate the effects of lactic acid bacteria (LAB), cellulase enzyme, molasses, and their combinations on the fermentation quality and in vitro digestibility of coconut peel (CCP), sugar palm peel (SPP), and durian peel (DRP) silage. The CCP, SPP, and DRP were ensiled in a small-scale silo without additive (control), and with LAB strain TH14 (TH14), molasses, or Acremonium cellulase (AC) using a small-scale silage preparation technique according to a completely randomized design. All fresh peels had sufficient factors for ensiling such as moisture content (78–83%), water-soluble carbohydrates (WSC, 4.20–4.61% dry matter (DM)), and epiphytic LAB population (104–105 colony-forming units (cfu)/g fresh matter (FM)). However, aerobic bacteria counts were high (107–109 cfu/g FM). The fiber content of these fruit peels was high, with lignin abundances ranging from 9.1–21.8% DM and crude protein was low (2.7–5.4% DM). After ensiling, the pH values of the silage were optimal (≤4.25) and lower (p &lt; 0.01) for SPP silage. The addition of molasses+TH14, molasses+AC, and molasses+TH14+AC has the potential to enhance fermentation characteristics and improve chemical composition. Silages treated with molasses alone improved the in vitro digestibility of tropical fruit peels. The residue of tropical fruits has the potential to be used as an alternative feed source for ruminants. Adding molasses, TH14, and AC during silage preparation could improve its nutritive value and digestibility.