Total Viable Count Research Articles

The microbial contaminants of plant-based meat analogues from the retail market

The aim of the study was to analyse the key microbial contaminants of plant-based meat analogues (PBMA) from retail. A total of 43 samples of PBMAs (12 frozen/31 chilled) in the “ready-to-cook” category, such as hamburgers, meatballs or breaded imitation steaks were purchased in retail stores in the Czech Republic in summer (n = 21) and autumn 2022 (n = 22). The detected indicator bacteria (total viable count, lactic acid bacteria, Enterobacteriaceae, yeasts, moulds) had relatively low values in the analysed PBMA samples and only rarely reached levels of 7 log CFU/g. E. coli, STEC and coagulase-positive staphylococci were not detected by isolation from plates in any of analysed samples. Mannitol positive Bacillus spp. were isolated from almost half of the analysed samples of the PBMA. B. cereus sensu lato was isolated from 3 samples by isolation from plates, and after enrichment in 35 samples (81 %). Clostridium perfringens could not be detected by isolation from plates, nevertheless after multiplication, it was detected in 21 % of samples. Analyses of PBMA samples revealed considerable variability in microbial quality. The presence of spore-forming bacteria with the potential to cause foodborne diseases is alarming. However, to evaluate the risks, further research focused on the possibilities of growth under different conditions of culinary treatment and preservation is needed.

Application of Lactiplantibacillus plantarum hydrogel coating in combination with ice temperature for the preservation of fresh yak meat

Fresh yak meat is highly nutritious and prone to spoilage, so developing suitable preservation methods is crucial. In this study, hydrogel coatings composed of konjac glucomannan, Lactiplantibacillus plantarum and gallic acid (KGX) were applied to preserve fresh yak meat under ice temperature (−1 °C). After 16 days, KGX group showed lowest total viable count (5.3 ± 0.1 log cfu/g) and total volatile basic nitrogen (13.02 ± 1.40 mg/100 g), which did not exceed the relevant standards of fresh meat. Combined assessments of color, texture, pH, drip loss rate, and thiobarbituric acid reactive substances indicated that KGX coating effectively prolonged yak meat preservation. High-throughput sequencing revealed that KGX coating effectively reduced the abundance of Pseudomonas and Candida. The application of L. plantarum hydrogel coatings in conjunction with ice temperature increased the shelf life of fresh yak meat to 16–20 days, suggesting its potential as a viable preservation method for fresh meat.

Enhancing frozen chicken meat quality by isochoric storage as compared with conventional frozen storage

Isochoric freezing is an emerging technique for preserving food at subfreezing temperatures under moderately high pressure. This study investigated the impact of isochoric frozen storage (IFS) of chicken breast for 0, 3, 6, 9, 12, and 15 days using 2.5% NaCl solution at −4 °C on qualities including physicochemical and microbial attributes, as compared with samples under conventional frozen storage (CFS) at the same temperature. Results showed IFS samples exhibited slight enhancements in various quality parameters, including pH, protein solubility, TBARS, drip loss, shear force, yellowness, cooking loss, and a slow decreasing rate in lightness, redness, Ca2+-ATPase activity, total viable count, and TVB-N, while substantial changes occurred in CFS samples for all quality parameters. This suggests that the impact of high pressure in isochoric freezing would be advantageous in terms of microbial destruction and enzymatic inhibition, potentially offering better long-term preservation techniques for the industry.

Preparation and properties of PCL coaxial electrospinning films with shell loaded with CEO and core coated LEO nanoemulsions

During storage and transportation, the reduction of microbial contamination and management of the exudation of fluids from the fish can effectively mitigate spoilage and degradation of fish fillets. In this work, the coaxial electrospinning films loaded with natural plant preservatives, namely laurel essential oil (LEO) and clove essential oil (CEO), were prepared by the coaxial electrospinning method synergistic with nanoemulsion techniques, and the hydrophilic preservation pads were prepared. The morphology of the film fiber is clear, without beads or damage, with fiber diameters falling within the 230–260 nm range. It has a distinct core–shell structure, exceptional thermal stability, and strong antibacterial and antioxidant properties. The core–shell structure of the fiber subtly regulates the release of preservatives and significantly improves the utilization efficiency. At the same time, the synergistic use of two essential oils can reduce the amount while amplifying their effectiveness. The pads significantly slowed down the increase of key indicators of spoilage, such as total viable count (TVC), pH, thiobarbituric acid reactive substances (TBA), and total volatile base nitrogen (TVB-N), during the storage of the fish fillets. Furthermore, the pads effectively slowed down the decline in water-holding capacity, the deterioration of textural qualities, and the negative changes in the microstructure of the fish muscle. Ultimately, the pads notably delayed the spoilage of fish fillets, extending their shelf life from 5 d to 9 d. The efficient utilization of biological preservatives in this film can provide technical support for the development of food preservation materials.

Nontargeted metabolomics reveals dynamic changes in the quality of fresh yak meat during ice-temperature preservation

Fresh yak meat is nutritious but susceptible to deterioration. The development of effective preservation techniques for fresh yak meat is highly important. In this study, the quality changes of fresh yak meat during ice-temperature (−1 °C) preservation and refrigerated (4 °C) preservation were evaluated. Within 15 days of preservation, the quality indicators of the yak meat preserved at ice temperature did not exceed the national standards, but the shelf life of the refrigerated meat was only 5 days. The TBARS, TVB-N, total viable counts of ice-temperature-treated meat were significantly lower than those of refrigerated meat. The dynamic changes in the metabolome of ice-temperature preservation meat were also investigated. A total of 2954 metabolites were annotated, and differentially regulated metabolites were mainly concentrated in amino acids and their metabolites, fatty acyls, benzene and its derivatives, aldehydes, ketones and esters, organic acids and its derivatives, etc. The significantly differentially regulated metabolites were mainly involved in protein and lipid oxidation. KEGG enrichment analysis revealed that the major metabolic processes involved in the deterioration of yak meat during ice-temperature preservation were purine metabolism, ABC transporters, biosynthesis of cofactors, biosynthesis of amino acids, nucleotide metabolism, glycerophospholipid metabolism, linoleic acid metabolism, and phenylalanine metabolism.

Development of Dusun Traditional Fermented Fish (Bosou Ikan) Using Different Concentrations of Tuhau (Etlingera coccinea)

This study aimed to determine the best formulation of Dusun traditional fermented fish (Bosou ikan) through sensory evaluation employing a 9-point hedonic test. Various concentrations of Etlingera coccinea, ranging from 0% to 8% w/w, were incorporated into fermented fish samples. Results revealed that the formulation containing 2% E. coccinea (F1) consistently exhibited superior sensory attributes, maintaining the traditional appearance while enhancing aroma, taste, and overall acceptability. Statistical analysis using the Friedman test confirmed F1's superiority, showing the lowest mean rank among alternatives (p<0.05). Proximate analysis of F1 demonstrated notable increases in ash, crude fat, crude fiber, and crude protein content compared to Control Bosou ikan formulations, indicating enhanced nutritional profiles. Shelf-life analysis demonstrated a more controlled trend in reducing total viable count and total yeast and mold counts for the F1 formulation compared to the control, suggesting a potential influence of E. coccinea in inhibiting excessive microbial proliferation. Comparison of microbial loads between raw and cooked samples revealed that cooking effectively eliminated microbial counts, reaching safety consumption levels of 4 log10 CFU/g (total yeast and mold) and 6 log10 CFU/g (total viable count). The decrease in pH of raw and cooked samples over one month was attributed to increased acidity resulting from the activities of Lactobacillus sp., which utilizes carbohydrates in the medium to produce lactic acid. The study highlights that the F1 formulation with 2% Etlingera coccinea offers the most favourable sensory characteristics, proximate analysis, and microbial quality, providing valuable insights for product development in Bosou ikan production.

Designing the pH-sensitive indicator based on starch nanoparticle with bromocresol green for monitoring meat spoilage

ABSTRACT The starch nanoparticle, combined with bromocresol green (BCG), served as a pH-sensitive indicator to monitor meat quality throughout an 8-day refrigerated storage period. The meat samples were sealed in package which the pH-sensitive indicator attached to the interior part of packaging lid. The changes in meat quality were evaluated by total volatile base nitrogen (TVBN), pH, total viable count (TVC), sensory analysis, and color in interval of 0, 3, 5, 7, and 8-days storage at 4°C. Initial TVBN values were recorded at 19.6 mg/100 g, increased to 26.6 mg/100 g by the end of storage period. The pH value was significantly increased after 8 days storage at 4°C. The observed color variation in the indicator from yellow to blue was attributed to the concurrent increases in TVBN, TVC, and pH. The indicator color changes had significant correlation with analyzed chemical quality of stored meat. Therefore, the designed BCG pH-sensitive indicator could be effective in monitoring the meat spoilage during storage.

Novel Halogenated Curcumin-Mediated Photodynamic Inactivation for the Preservation of Small Yellow Croaker (Larimichthys polyactis).

A novel class of halogenated curcumin, X-Cur (X = F, Cl, or Br), was synthesized, and its photosensitivity was evaluated. The results showed that Br-Cur with the highest singlet oxygen (1O2) generation capacity exhibited a better photodynamic inactivation (PDI) effect on the small yellow croaker (Larimichthys polyactis) than curcumin. This was attributed to the heavy atom effect of Br, which resulted in Br-Cur having the smallest singlet-triplet energy difference ΔEst(S1-T3) (0.140 eV) and the largest spin-orbit coupling value (0.642262 cm-1). When L. polyactis was treated with 0.025 wt % Br-Cur and exposed to blue LED irradiation (450 nm, 20 mW/cm2) for 20 min, the increase in the total volatile basic nitrogen content (28.23 ± 2.38 mg/100 g on day 6), pH, and total viable count (6.13 ± 0.06 log CFU/g on day 6) could be effectively controlled. Accordingly, Br-Cur is a promising photosensitizer for PDI preservation.

Quality tracking of largemouth bass (Micropterus salmoides) fillets during superchilling storage by pretreatment with NaCl

The objective of this research was to investigate the effect of salt pretreatment (1 % and 2 %) on the physicochemical properties, sensory characteristics and safety indices of largemouth fillets during superchilling storage. During superchilling storage, the 2 % group had the lowest values of ice crystal formation temperature, thiobarbituric acid (TBA), total volatile basic nitrogen (TVB-N), and total viable counts (TVC), and the deterioration of fish quality in the 2 % group was significantly slower than that in the 1 % group (P<0.05). At the later stage of storage, low-field nuclear magnetic resonance (LF NMR) results showed that moisture in the fish fillets showed a mixture of ice crystals and water, and TBA, TVB-N, and TVC values were significantly higher in the salt-treated group (P<0.05); the proteins interacted with unfrozen fractions to form relatively ordered structures, which promoted the intensity of protein bands. The pH of the fillets transferred from neutral to weakly acidic throughout the period of storage, and the L*, W and b* values of the 2 % group were significantly lower (P<0.05) than those of the other two groups. The results of shear force, microstructure and western blot (WB) indicated that salt pretreatment significantly improved fillet tenderness and odor. These indicated that the ideal salt pretreatment concentration and quality of the bass fillets for superchilled storage were 2 % and 21 d, respectively. This study provides a theoretical basis for the application of the preservation of aquatic products.

Real-time tracking of fish quality using a cellulose filter paper colorimetric indicator incorporated with prickly pear fruit betacyanins

In the present work, a freshness indicator was developed by immobilizing extracted betacyanins from prickly pear fruit (PFB) onto cellulose filter paper to visually determine fish spoilage. Various properties of the prepared indicator, including color stability, moisture uptake, sensivity to hydrogen sulfide (H2S) gas and pH changes, and chemical analysis were studied. The PFB-based indicator exhibited good color stability at various temperatures and times, with no significan color changes observed during storage at 25, 4, and −18 °C for 8 days. The moisture absorption of the indicator based on PFB was lower than that of cellulose paper, which is crucial for colorimetric indicators. Basic nitrogen and sulfur compounds are the main volatile compounds produced during fish spoilage. The results of the present study showed that both total volatile basic nitrogen (TVB-N) and H2S gas produced during fish spoilage contributed to the color changes of betacyanin-based colorimetric indicators. The prepared freshness indicators were pH-sensitive, with significant color changes due to TVB-N and H2S production during fish storage. A significant correlation was observed between fish quality (pH, TVB-N and total viable count) and the visible color changes of the indicators. The color of the designed indicator shifted from dark pink to pale pink/white during fish storage. These prepared freshness indicators were inexpensive, easy to use, and non-toxic, making them suitable for assessing the quality and shelf life of fish fillets.

Spatial distribution of faecal indicator bacteria around Kanyakumari coast, Southernmost point of Mainland India

Coastal and marine ecosystems should be sustained by maintaining the better environmental quality for our well-being. The goal of this study was to assess the water quality on the coastlines of Kanyakumari, the southernmost part of Indian mainland. Distribution and abundance of indicator bacteria and opportunistic pathogens related to fecal contamination and antibiotic resistance of the isolates were studied to observe the influence of anthropogenic pressures on coastal waters. Water samples were collected from July’22 to September‘22 from three different ecosystems: Chinnamuttom harbor, Kovalam coast and Manakudy estuary. At each site physio–chemical parameters were noted. Simple main effects analysis showed that the sites have a statistically significant difference in total viable count and total coliform count (p < 0.05). A total of eight indicator bacteria such as E. coli, Klebsiella sp., Enterococcus sp., Aeromonas sp., Proteus mirabilis, Salmonella typhi, Vibrio cholerae and Vibrio paraheamolyticus were identified. Antibiotic sensitivity test by Kirby-Bauer Disk Diffusion method was performed to identify sensitivity pattern of antibiotics. The isolates were exposed to ten antibiotics. All the isolates were resistant to at least one antibiotic, and penicillin was the predominant. Presence of fecal indicators indisputably reveals that the chosen sites are receiving untreated sewage loaded with fecal matter which might have detrimental effect on coastal waters.

Impact of Packaging Methods Coupled with High Barrier Packaging Loaded with TiO2 on the Preservation of Chilled Pork.

This study investigated the impact of packaging methods coupled with high barrier packaging loaded with titanium dioxide (TiO2) on the quality of chilled pork. The experiment consisted of three treatment groups: air packaging (AP), vacuum packaging (VP), and vacuum antibacterial packaging (VAP). Changes in total viable count (TVC), pH value, total volatile basic nitrogen (TVB-N) value, sensory attributes, and water holding capacity of pork were analyzed at 0, 3, 6, 9, and 12 d. TVC of the VAP group was 5.85 Log CFU/g at 12 d, which was lower than that of AP (6.95 Log CFU/g) and VP (5.93 Log CFU/g). The antibacterial film incorporating TiO2 effectively inhibited microorganism growth. The VAP group exhibited the lowest pH value and TVB-N value among all the treatment groups at this time. The findings demonstrated that the application of VAP effectively preserved the sensory attributes of pork, the hardness, cohesiveness and adhesiveness of pork in VAP group were significantly superior than those in AP group (p<0.05), but not significantly compared with VP group. On the 12 d, the CIE a* value of pork in VAP group was significantly higher (p<0.05). This exhibited that VAP could effectively maintain the freshness of chilled pork and extend the shelf life for 3 d compared to the AP group. These findings provide empirical evidence to support the practical implementation of TiO2-loaded packaging film in the food industry.

Microbial Assessment of Spoilt Tomatoes (Solanum lycopersicum Linn) Being Sold in Some Markets in Ondo City, Nigeria

Tomatoes (Solanum lycopersicum Linn) are one of the most consumed fruits in Nigeria and the world at large but they are highly susceptible to microbial spoilage. Consumption of these spoilt tomatoes could increase the risk of food poisoning and also cause serious health issues which are of public health concern. This study was therefore designed to investigate the bacteria and fungi associated with spoilt tomatoes being sold in some selected markets in Ondo city. Different media (Nutrient, MacConkey, Mannitol Salt, Salmonella –Shigella, Eosin Methylene Blue, Sorbitol MacConkey and Potato Dextrose agar) were used for the determination of the total viable bacterial and fungal counts from the samples collected from Odoshida, Adeyemi and Iyalaje markets in Ondo using the pour plate technique. The isolates obtained after subculturing were characterized based on their cultural, morphological and biochemical characteristics. The total bacterial count ranged from 1.25 ×108 to 8.06 ×108cfu/mL while the total fungal count ranged from 2.75 ×105 to 5.65 ×106 cfu/mL. The identified bacteria obtained were Staphylococcus species, Proteus species, Salmonella species, Pseudomonas species, Escherichia coli, Klebsiella species, Shigella species, Enterobacter species and Bacillus species, while the fungi were Alternaria species, Penicillium species, Aspergillus species, and Rhizopus species. This study has shown that all the isolates obtained from the selected samples are of public health concerns because of their pathogenic and toxigenic nature; an indication that spoilt tomatoes ordinarily should not be consumed or consumed with utmost caution.

Effect of Calcium Chloride and Trisodium Phosphate Fortification on Low Fat Buffalo Milk Cheeses

Cheese is a dairy product that is highly preferred by consumers. Cheese is a delectable and nutritious food item. Enhancing the quality of cheese necessitates innovation in cheese processing. The objective of the study was to determine the impact of calcium chloride and trisodium phosphate on the physical, chemical, microbiological, and rheological characteristics (namely firmness) of low-fat buffalo milk cheeses. This study had a fully randomized design, consisting of nine treatments and three replications. The cottage cheese, mozzarella, and cheddar were treated with varying quantities of calcium chloride and trisodium phosphate (10, 20, and 30 mM) and then stored for a period of 30 days. The cheeses supplemented with salt exhibited a noteworthy (p≤0.05) rise in pH, total nitrogen (TN), non-casein nitrogen (NCN), and non-protein nitrogen (NPN) for nearly all treatments. However, a subsequent decline was noted after storage. Similarly, the hardness (N) significantly improved (from 330.33 to 454) among treatments and reduced (from 427 to 276.33) after 30 days of storage, with a p-value of ≤0.05. In addition, the total plate count (TPC) and total viable count (TVC) showed an upward trend during the ripening phase. In conclusion, it was observed that the physicochemical, rheological, and microbiological quality characteristics of cheeses can be effectively regulated with appropriate mineral fortification.

An antibacterial film using κ-carrageenan loaded with benzyl isothiocyanate nanoemulsion: Characterization and application in beef preservation

Benzyl isothiocyanate (BITC) is a naturally active bacteriostatic substance and κ-carrageenan (KC) is a good film-forming substrate. In the present study, a nanoemulsion incorporating BITC was fabricated with a particle size of 224.1 nm and an encapsulation efficiency of 69.2 %. Subsequently, the acquired BITC nanoemulsion (BITC-NE) was incorporated into the KC-based film, and the light transmittance of the prepared composite films was lower than that of the pure KC film. Fourier transform infrared spectroscopy and scanning electron microscopy revealed that BITC-NE was compatible with the KC matrix. BITC-NE incorporation enhanced the tensile strength of the KC-based films by 33.7 %, decreased the elongation at break by 33.8 %, decreased the water vapor permeability by 60.1 %, increased the maximum thermal degradation temperature by 48.8 %, and decreased the oxygen permeability by 42 % (p < 0.05). Furthermore, the composite films showed enhanced antimicrobial activity against Staphylococcus aureus, Salmonella typhimurium, and Pseudomonas fluorescens. The developed KC-based composite films were applied to wrap raw beef, which significantly delayed the increase in total viable count, total volatile base nitrogen content, and thiobarbituric acid reactive substances, and prolonged the shelf-life of the raw beef by up to 10 days. These results indicated that the composite films prepared by incorporating BITC nanoemulsions into KC matrices have great antimicrobial application potential.

The drainome: longitudinal metagenomic characterization of wastewater from hospital ward sinks to characterize the microbiome and resistome and to assess the effects of decontamination interventions

BackgroundHospital drains and water interfaces are implicated in nosocomial transmission of pathogens. Metagenomics can assess the microbial composition and presence of antimicrobial resistance genes in drains (‘the drainome’) but studies applying these methods longitudinally and to assess infection control interventions are lacking. AimApply long-read metagenomics coupled with microbiological measurements to investigate the drainome and assess the effects of a peracetic acid-containing decontamination product. Methods12-week study in three phases: a baseline phase, an intervention phase of enhanced decontamination with peracetic acid, and a post-intervention phase. Five hospital sink drains on an intensive care unit were sampled twice weekly. Each sample had 1) measurement of total viable count (TVC), 2) metagenomic analyses including i) taxonomic classification of bacteria and fungi ii) antibiotic resistance gene detection iii) plasmid identification, and 3) immunochromatographic detection of antimicrobial residues. FindingsOverall TVCs remain unchanged in the intervention phase (+386 CFU/mL, SE 705, p=0.59). There was a small but significant increase in the microbial diversity in the intervention phase (-0.07 in Simpson’s index, SE 0.03, p=0.007), which was not sustained post-intervention (-0.05, SE 0.03, p=0.08). The intervention was associated with increased relative abundance of the Pseudomonas genus (18.3% to 40.5% [+22.2%], SE 5.7%, p<0.001). Extended spectrum beta-lactamases were found in all samples, with NDM-carbapenemase found in 3 drains in 6 samples. Antimicrobial residues were detected in a large proportion of samples (31/115, 27%), suggesting use of sinks for non-handwashing activities. ConclusionsMetagenomics and other measurements can measure the composition of the drainome and assess the effectiveness of decontamination interventions.

Evaluation of the efficacy of rice bran and sesame oil for producing nutritionally-superior quality functional tofu

Paneer prepared from edible-quality de-oiled soy flour is known as tofu. Functional tofu was augmented with specific antioxidants such as oryzanol and lignan obtained from rice bran oil (RBO) and sesame oil (SO), respectively. All the fortified and control tofu were evaluated for physicochemical (proximate composition, oxidative stability, antioxidant activity, penetration, and color property), microbiological, and sensory properties. The total viable count and yeast and mold counts increased slowly in the samples stored at 4 °C in the refrigerator for 9 days. Fortified tofu showed higher oxidative stability and antioxidant activity than the control tofu during storage conditions. Additionally, tartaric acid-coagulated tofu retained its quality attributes, especially taste and overall acceptability, during refrigerated storage. Functional tofu aided in an innovative technological technique for making functional non-dairy products with boosted healthy constituents.

Sun-Dried and Convective-Dried Octopus vulgaris Quality Parameters and Estimated Shelf Life During Ambient Temperature Storage

ABSTRACT Drying process was used in this study as a preserving method of octopus quality during storage. Octopus vulgaris quality attributes in terms of pH, water activity, color properties, total volatile basic nitrogen (TVB-N), trimethylamine (TMA), total viable count, and yeast and molds (YM) were evaluated. Samples were dried under sun drying and convective air drying and stored at ambient temperature. During storage, TVBN and TMA obtained were within the recommended level for good quality of dried samples. Accelerating shelf-life test was evaluated based on TVB-N, TMA, and YM, with shelf lives of 388 and 603 days for convective air drying and sun drying, respectively.

Integrated approach of ultrasound with mild heat treatment on the quality characteristics of yacon (Smallanthus sonchifolius) tuber juice

AbstractThe research delved into the ascendancy of thermosonication (TS) on elevating the alimentary components of yacon (Smallanthus sonchifolius) tuber juice, derived from the yacon plant. This investigation introduces an innovative approach utilizing artificial neural networks (ANNs) coupled with genetic algorithm (GA) for the multifaceted optimization of extraction procedures. It aims to pinpoint the most effective processing parameters for TS, including variations in amplitudes: X1 (40, 50, and 60%) and temperatures: X2 (30, 40, and 50°C) over sonication times: X3 (15, 30, 45, and 60 min). Further, the approach is focused to amplify quality of yacon juice (YJ) and microbial attributes by enhancing certain quality characteristics such as anti‐oxidant activity (AOA), ascorbic acid (AA), total phenolic content (TPC), total carotenoid content (TCC), total flavonoid content (TFC), yeast and mold count (YMC) and total viable count (TVC). The maximum levels of AOA (33.73 ± 2.21%), AA (25.82 ± 2.03 mg/100 ml), TPC (85.08 ± 3.67 mg GAE/ml), TCC (115.82 ± 2.46 βCE μg/ml), TFC (22.52 ± 2.11 mg QE/ml), TVC, and YMC (not detected) were achieved in thermosonicated YJs under optimal conditions using ANN coupled with GA.Practical ApplicationsYacon tuber juice (YJ) treated with thermosonication (TS) showed improved nutritional characteristics, making them a valuable source of functional compounds for nutraceuticals and food industries. Research emphasizes the effectiveness of artificial neural network in predicting the extraction efficiency of YJ and proposes TS as a potential replacement for traditional thermal pasteurization to maintain or enhance YJ quality and functionality. TS provides cost‐effective and sustainable solutions to the food industry by reducing processing time and energy consumption when compared to pasteurization.

Fabrication and characterization of Karaya gum-based films reinforced with bacterial nanocellulose stabilized valerian root extract Pickering emulsion for lamb meat preservation

A novel biodegradable film was fabricated by incorporating bacterial nanocellulose stabilized valerian root extract (VRE) Pickering emulsion into karaya gum with better antioxidant and antibacterial properties for lamb meat preservation. The valerian root extract Pickering emulsion (VPE) exhibited 98 ± 1.84 % encapsulating efficiency and excellent physical stability with an average particle size of 274.6 nm. The incorporation of VPE-5 into the film matrix increased its elongation at break (EAB), and improved water resistance and barrier properties against oxygen, water vapor, and UV light. Moreover, the antioxidant and anti-bacterial properties against S.aerous and E. coli were also improved based on VPE-5 concentration. The SEM images showed a uniform distribution of VPE-5 while FTIR and XRD revealed its compatibility with karaya gum, which improved its thermal stability. The active films showed a significant preservative effect by reducing the pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), and total viable count (TVC) value of lamb meat and maintained its texture and color during the storage period of 9 days at 4 °C. These results demonstrated the inclusion of VPE-5 into Karaya gum was a promising technique and offers a great potential application as a bioactive material in food packaging.