Beef Slices Research Articles

Malva neglecta seed polysaccharide mucilage coating enriched by the Lactobacillus brevis TD4 postbiotics: A promising strategy to promote the shelf life of fresh beef

The need for bioactive-incorporated biodegradable packaging products is growing due to the desire to achieve food goods that have a longer shelf life and enhanced safety. The current study set out to create an edible coating using Malva neglecta seed polysaccharide mucilage (MNSM) containing Lactobacillus brevis TD4-derived postbiotics (PLB), and assess how well the PLB-MNSM edible coating preserved beef slices over a 12-day period of refrigeration. PLB was rich in fatty acids, organic heteropolycyclic compounds, monoterpene and cyclohexanol derivative, prenol lipids, ester compounds, and alpha-CH2-containing aldehyde with significant antimicrobial and antioxidant activities. By adding it to the edible coating at 0, 5, 10, and 15 % v/v, it successfully prevented the proliferation of microbial agents (total viable count, psychrotrophic count, Staphylococcus aureus, Escherichia coli, total coliform bacteria count, and fungi) as well as the oxidation of lipids (thiobarbituric and peroxide values) in beef samples. The samples' pH value, hardness, and moisture content were all more successfully sustained when PLB preparation was applied to the coating solution (P < 0.05). The edible coating consisting of PLB effectively maintained the meat color (L*, a*, b*) and sensory properties. Additionally, the bioactive edible coating comprised of MNSM and PLB, specifically MNSM-15 % PLB, significantly prevented the quality deterioration of beef samples and prolonged the shelf-life of the meat to over 12 days. The outcomes indicated that the MNSM-PLB edible coating has the capacity to be utilized as an antibacterial and antioxidant-rich packing material, hence enhancing the shelf life of meat-based goods.

Effect of alterations in phospholipids and free fatty acids on aroma-active compounds in instant-boiled chuck tender, sirloin and silverside beef

Beef flavor profiles are strongly influenced by cooking methods and lipid composition. However, the effect of instant-boiling on the aroma of different beef slices was unclear. This study investigated the lipid profiles and instant-boiling volatile profiles of chuck tender (M. Supraspinatus), sirloin (M. Longissimus dorsi) and silverside (M. Biceps femoris). Quantitative lipidomics identified 336 lipid molecular species, of which 84–112 were quantitatively different among the three beef slices. Sirloin had lower phosphatidylcholine, phosphatidylinositol, phosphatidylglycerol and free fatty acids than chuck tender and silverside. The unsaturated fatty acid acyl chains in phosphatidylethanolamine differed significantly. Solid phase microextraction-gas chromatography-olfactometry-mass spectrometry (SPME-GC-O-MS) identified hexanal, octanal, nonanal, decanal, (E)-2-octenal, (E)-2-nonenal, (E)-2-undecenal, (E,E)-2,4-nonadienal, (E,E)-2,4-decadienal, 1-octen-3-ol, 2-pentylfuran and acetoin as the aroma-active compounds of instant-boiled beef. Unsaturated free fatty acids and phosphatidylglycerols with unsaturated fatty acid residues positively correlated with the aroma-active compounds and might be crucial in flavor differences among the three beef slices. These findings provide greater understanding of the lipid and instant-boiling aroma-active compound profiles in chuck tender, sirloin and silverside, and reflect the suitability of different beef slices for instant-boiling from the aroma perspective.

Exploring the potential of melittin peptide: Expression, purification, anti-pathogenic properties, and promising applications as a bio-preservative for beef slices

Melittin peptide is a short cationic linear peptide derived from honey bee venom with 26 amino acids, demonstrates potential in controlling and eliminating pathogens. In this study, the genetic sequence of melittin was inserted into the pcDNA3.1+ plasmid and expressed in HEK-293 cells with a His-tag. Purification was done through affinity chromatography and a nickel column. In this study, the antimicrobial effect of melittin in beef sirloin was first investigated, and the minimum inhibitory concentration (MIC) was determined. Then, the effect of combining it with nanochitosan (n-CH) coating, melittin (0.1% and 0.2%v/v), and nanochitosan alone on the physicochemical, microbiological, and sensory properties of beef was examined over a 9-day at 4 °C. At the end of the storage period, the coated samples effectively prevented an increase in pH (5.75 ± 0.06) and showed a significant decrease in the peroxide value (PV) (4.50 ± 0.07). The most favorable result was observed when using the n-CH+0.2%M, which led to malondialdehyde level of 0.44 ± 0.0.05 mg/kg in the amount of thiobarbituric acid reactant. Additionally, the total volatile base nitrogen content in the treatment involving 0.2%M and n-CH+0.2% and 0.1%M was deemed acceptable. Although the total viable count (TVC) of microorganisms in samples covered with melittin increased over time (7.88 ± 0.12 CFU/g), the microbial growth rate in these samples was lower than the control sample (12.10 ± 0.13 CFU/g). Therefore, the use of nanochitosan based edible coatings in combination with melittin in meat packaging reduces microbial population and increases its shelf life.

Potency of Chitosan as A Bioactive Edible Coating on Some Meat Cuts

The goal of this study was to examine how chitosan and nano-chitosan affected beef quality criteria. Moisture, ash, protein, fat, and pH were all measured. In beef slices, enterobacteria, psychophilic bacteria, yeast, mold, HPC, and coliforms were enumerated to see how much chitosan and its nanoform affect them as an antibacterial. For this experiment, 27 beef slices were purchased from a neighboring market and delivered to the lab in a chilled box. Nine of which had meat portions treated with a 1% chitosan solution, nine with a 1% nano-chitosan solution, and nine as a control (not treated). According to the study's findings, adding chitosan to meat cuts in both forms enhances meat quality by reducing levels of HPC, yeast, mold, coliforms, enterobacteria, and psychrotrophic bacteria while boosting moisture, ash, protein, fat, and pH. According to the results, treating the beef slices with 1% nano-chitosan was more effective than chitosan alone. In conclusion, treating meat and its byproducts, as well as diets and feeds, with nanoparticles derived from natural materials such as chitosan may be more efficacious than utilizing metal nanomaterials.

Comparative analysis of helium and air surface micro-discharge plasma treatment on the microbial reduction and quality attributes of beef slices

This work aimed to compare the effects of helium and air surface micro-discharge (SMD) plasma on the microbial safety and quality of beef tissues. For the beef tissue model, the concentration and diffusion depth of hydroxyl radical and ozone have different change patterns over plasma treatment time and distance in helium and air SMD plasma. The inactivation efficiency of helium plasma depended on the plasma treatment time and distance, while the inactivation efficiency of air plasma only depended on the treatment time. For the fresh beef slices, air SMD plasma treatment exhibited a higher antimicrobial activity against S. aureus and E. coli than helium SMD plasma treatment (1.5 versus 0.9; 0.9 versus 0.28 log CFU/g at 10 min). However, air SMD plasma treatment caused more adverse effects on beef quality, leading to a smooth surface, extensive lipid oxidation, protein structure damage, low pH and discoloration compared to helium SMD plasma treatment. This work provides valuable guidelines for the working gas choice in the practical application of plasma to meat decontamination.

Image based beef and lamb slice authentication using convolutional neural networks

Meat adulteration affects customers and the market. Existing meat authentication methods usually rely on special devices, and thus are limited to professional use only. Fake lamb or beef slices made from duck and fat appear in some Chinese hotpot restaurants. This study present a customer–conducted method for detecting such adulteration. The method takes a single image as input, and authenticates it by using the textural features of meat slices. The authentication is rapid and non–destructive. The only device required is a mobile phone with a camera. A lightweight (thus high–efficient) convolutional neural network architecture called MTx–Net was built for this task. Fourteen convolutional layers in four blocks were used for extracting valid visual features. Techniques like residuals, depth–wise convolution, dropout and batch normalization were employed in the neural network. For training and testing the neural network, 77956 meat images were collected using 225Kg of meats. This method achieves 99.38% and 98.20% accuracy on lamb and beef slice authentication, respectively.

Effects of Sodium Alginate Edible Coating with Cinnamon Essential Oil Nanocapsules and Nisin on Quality and Shelf Life of Beef Slices during Refrigeration

The effects of a new edible sodium alginate (SA) coating incorporating cinnamon essential oil nanocapsules (CEO-NPs) and nisin were investigated with beef slices in refrigerated storage for 15 days. All beef samples were analyzed for physicochemical properties (pH, weight loss, and total volatile base nitrogen) and antimicrobial activity against total bacteria. Changes in color parameters and sensory attributes of all beef samples also were evaluated. Incorporation of the complex of CEO-NPs and nisin into the SA coating retarded the growth of microorganisms and reduced lipid oxidation, as determined by pH, total volatile base nitrogen, and total bacteria counts. This treatment also extended the shelf life of beef slices to 15 days. The SA coating with CEO-NPs and nisin significantly reduced weight loss and improved color, odor, texture, and purge quality of the beef samples. These results suggest that treatment with the SA coating enriched with CEO-NPs and nisin can significantly retard the deterioration of beef slices, and the complex of CEO-NPs and nisin can improve antioxidant, antibacterial, and sensory properties of the SA coating. This new edible coating could be useful for preserving beef slices.

Droplet Digital PCR (ddPCR) Analysis for Detecting Shiga-Toxin-Producing Escherichia coli (STEC)

Verocytotoxin-producing Escherichia coli, also referred to as Shiga-toxin-producing Escherichia coli (STEC), can be transmitted to humans through person-to-person contact, consumption of contaminated food or water, or by direct contact with animals. Its clinical and economic consequences have prompted the development of alternative approaches to the official method of analysis “UNI CEN ISO/TS 13136: 2012”, which describes the identification of STEC through the detection of its main virulence genes. Recently, droplet digital PCR (ddPCR) has been proposed as a technique for the sequence-specific detection and direct quantification of nucleic acids. The present study aimed to investigate if ddPCR could be able to detect STEC in less time than that required by the official method. This study consisted of the ddPCR of slices of beef contaminated with STEC and of the sponges used for beef official control at the slaughter stage. The results showed the ability of ddPCR to detect STEC in slices of beef already after sample incubation for 7 h at 37 °C while, in the case of sponges used for official controls, 9 h at 37 °C was needed. In this way, the ddPCR could represent an efficient method for detecting STEC and providing results in less time than the official method.

Monitoring of moisture contents and rehydration rates of microwave vacuum and hot air dehydrated beef slices and splits using hyperspectral imaging

Effects of food microstructure and processing methods on moisture migration in food during processing are important for improving product quality. This study evaluated the effects of fibre directions and dehydration methods on beef dehydration and rehydration behaviours using near-infrared hyperspectral imaging. Beef slices (transversal cut) and splits (longitudinal cut) were dehydrated by hot air drying (HAD) and microwave vacuum drying (MVD). Results indicated the moisture in the slices evaporated faster than that in the splits during HAD and MVD processed samples exhibited higher rehydration rates than HAD ones. Principal component analysis showed great performance in clustering samples based on fibre directions, processing methods and time. The established simplified RC-SG-PLSR and RC-2nd Der-PLSR models possessed good prediction accuracies for moisture (R2p = 0.994) and rehydration rate (R2p = 0.889), respectively. Chemical distribution maps also confirmed the influence of fibre directions and dehydration methods on moisture migration in samples.

Translocation of Phthalates From Food Packaging Materials Into Minced Beef.

There has been increased concern regarding the potential human health risks associated with exposure to phthalates. Research indicates that food intake is the most critical exposure pathway for phthalates. This study aimed to investigate packaged beef samples for the presence of dimethyl terephthalate (DMTP), di-n-butyl phthalate (DnBP), and diisooctyl phthalate (DiOP) and to assess their translocation from the common form of food packaging procured from various Saint-Petersburg and Leningrad region shops. The packaging samples include paper and different types of plastic. Phthalates were extracted by dichloromethane and analyzed by gas chromatography coupled with mass spectrometry (GC-MS). While DnBP had the highest mean values in beef from 34.5 to 378.5 μg·kg−1, DiOP displayed the lowest mean values from LOD to 37 μg·kg−1. The larger contact area and the presence of distributed fat on the surface of the minced meat resulted in significantly higher phthalate translocation than beef slices. Further, DMTP was not detected in any samples. However, the examined food packages do not meet the requirements of Russian, EU and USA legislation, as DnBP migrates to meat. Calculated maximum DnBP daily intake of 0.167 μg·kg−1·day−1 for chilled minced beef in vacuum packaging did not exceed tolerable daily intake (TDI) level. The most alarming results are concerning the phthalates presence in beef farmed in the Leningrad region and not subjected to any plastic packaging. A full-scale study is warranted to determine the pathways and sources of phthalates migration in the food chain.

Effects of 405 ± 5-nm LED Illumination on Environmental Stress Tolerance of Salmonella Typhimurium in Sliced Beef.

Salmonella Typhimurium is a widely distributed foodborne pathogen and is tolerant of various environmental conditions. It can cause intestinal fever, gastroenteritis and bacteremia. The aim of this research was to explore the effect of illumination with 405 nm light-emitting diodes (LEDs) on the resistance of S. Typhimurium to environmental stress. Beef slices contaminated with S. Typhimurium were illuminated by 405 nm LEDs (18.9 ± 1.4 mW/cm2) for 8 h at 4 °C; controls were incubated in darkness at 7 °C. Then, the illuminated or non-illuminated (control) cells were exposed to thermal stress (50, 55, 60 or 65 °C); oxidative stress (0.01% H2O2 [v/v]); acid stress (simulated gastric fluid [SGF] at pH 2 or 3); or bile salts (1%, 2%, or 3% [w/v]). S. Typhimurium treated by 405 nm LED irradiation showed decreased resistance to thermal stress, osmotic pressure, oxidation, SGF and bile salts. The transcription of eight environmental tolerance-related genes were downregulated by the illumination. Our findings suggest the potential of applying 405 nm LED-illumination technology in the control of pathogens in food processing, production and storage, and in decreasing infection and disease related to S. Typhimurium.

Vacuum Frying Below the Triple Point of Water (VFBTPW) of Frozen Unmarinated Beef Slices

Vacuum Frying Below the Triple Point of Water (VFBTPW) of Frozen Unmarinated Beef Slices

Listeria monocytogenes sensitivity to antimicrobial treatments depends on cell origin

In this study we investigated how cell origin could affect the efficacy of an antimicrobial treatment (mild heating combined with terpenoids) in Listeria monocytogenes Scott A, considering cells from: 1. single colony, 2. glycerol stock, 3. cold adapted culture, and 4. fresh culture in stationary phase. After treatment, culturability on BHI medium and viability assessed by flow cytometry were evaluated. Our results showed that the cell origin significantly impacted viability and culturability of L. monocytogenes towards antimicrobial treatment. The mild heat treatment combined or not with terpenoids mainly affected culturability rather than viability, although the culturability of cells from single colony was less impacted. Therefore, to mimic the worst scenario, these latter were selected to contaminate Gorgonzola rind and roast beef slices and we evaluated the ability of L. monocytogenes cells to recover their culturability (on ALOA agar medium) and to growth on the food matrix stored at 4 °C for 7 days. Our results suggest that only Gorgonzola rind allowed a partial recovery of the culturability of cells previously heated in presence or not of terpens. In conclusion, we found a connection between the cell history and sensitivity toward an antimicrobial treatment, underlying the importance to standardize the experimental procedures (starting from the cells to be used in the assay) in the assessment of cell sensitivity to a specific treatment. Finally, our study clearly indicated that VBNC cells can resuscitate under favorable conditions on a food matrix, becoming a threat for consumer’s health.

Drying kinetics and quality characteristics of microwave-assisted hot air dried beef chips

In this study, the drying kinetics and quality characteristics of microwave-assisted hot air dried beef chips were investigated. For this purpose, beef slices were treated with spice mixture (4 g/100 g beef) and then dried with 2 different air temperature (60 and 70 °C) and 3 different microwave power (0, 90 and 180 W at fixed product weight). Drying process was terminated when moisture content of samples went below 15% and then drying kinetics and quality characteristics of the beef chips were analyzed. Drying time of beef chips reduced due to the increase in the microwave power and temperature whereas Page model was the most suitable model for identifying drying kinetics. It was also noted that average moisture content of microwave-assisted hot air dried beef chips was 12.8% (dry basis), water activity (aw) value was 0.70, pH value was 5.8 and thiobarbituric acid reactive substances (TBARS) value was 30.48 µmol MDA/kg. It was further found that those beef chips that were dried at high temperature (70 °C) and microwave power (180 W) had darker color (higher a* value) and shorter, thicker and harder (high cutting force). Moreover, it was finally noted that such fast drying samples had better microbial and sensory quality.

Effect of sodium alginate-agar coating containing ginger essential oil on the shelf life and quality of beef

Edible coatings based on agar/sodium alginate (AS) and AS containing ginger essential oil (AS + GEO) were prepared and their effects on the quality and shelf-life of fresh beef during refrigerated storage studied. Uncoated (control) and coated beef samples were analyzed periodically during storage at 4 °C for microbial colony growth (total viable counts, psychrotrophs, Escherichia coli , Staphylococcus aureus , yeasts and molds), physico-chemical (thiobarbituric acid reactive substances, peroxide value), pH value, sensory evaluation, odor (electronic nose) and texture characteristics (springiness, chewiness and hardness). Coating treatments significantly ( p < 0.05) retarded the oxidation of beef slices, with TBARS values of 3.132, 1.868, 0.986 mg MDA/kg and PV values of 8.86, 7.46, 4.26 meq/kg for uncoated, AS coated and AS + GEO coated samples on day 18 of storage respectively. A similar reduction trend was observed for microbial population. TVC, PTC, E. coli , S. aureus , yeasts and molds were 7.50, 6.86, 6.20, 4.70 and 3.90 log CFU/g at the end of storage for AS + GEO coated samples lower than those of uncoated and AS coated samples. The comprehensive results from the lipid oxidation and microbial assays (especially the TVC) showed that the shelf-life for uncoated, AS coated and AS + GEO coated samples was ~7 d, ~10 d, ~16 d, indicating the AS and AS + GEO coatings could extend the shelf life of fresh beef by 3–6 and 9 days respectively, compared with the control samples. Furthermore, the odor and texture evaluations demonstrated that the beef coated with AS + GEO had improved sensory attributes during the storage period. The results from this study may provide a basis for the development of AS + GEO as an antibacterial coating material for chilled beef storage.

Impact of drying temperature and salt pre-treatments on drying behavior and instrumental color and investigations on spectral product monitoring during drying of beef slices

Drying behavior and instrumental color development of beef slices untreated or pretreated with salt or salt and vinegar solutions were monitored by determining the moisture content and the color change by measuring CIELAB values during drying at 50, 60, and 70 °C. Time-series hyperspectral imaging (400–1000 nm) was applied with regard to the development of non-invasive measurement systems based on robust models to predict moisture and color independent of the pre-treatment and drying temperature. Samples pretreated with salt dried the slowest which became more prominent at increasing drying temperatures and the least color change (∆E = 23) was observed at 60 °C drying temperature. Robust prediction models for moisture content and CIELAB values irrespective of pre-treatment and processing conditions were developed successfully and improved by wavelengths selection with high R2 (0.94–0.98) and low RMSEP (1.05–5.22) which will support the future development of simple and cost-effective applications regarding non-invasive product monitoring systems for beef drying processes.

Control of microbial growth and lipid oxidation in beef using a Lepidium perfoliatum seed mucilage edible coating incorporated with chicory essential oil.

In this study, chicory essential oil (CEO) was obtained by hydrodistillation‐based extraction method and it was rich in camphor (31.3%) and phenolic compounds with outstanding antioxidant and antimicrobial properties. The CEO was then incorporated into Lepidium perfoliatum seed mucilage (LPSM) based aqueous solution to prepare an active CEO‐loaded LPSM edible coating. The effect of the edible coating was then investigated on the quality and shelf life of beef slices during 7 days storage at 4°C. The results revealed that beef slice coated with CEO‐loaded LPSM edible coating had a significant inhibitory effect on its lipid oxidation and microbial growth. The CEO‐LPSM coating also inhibited the weight and texture losses of beef slices during display more efficiently compared with the control and CEO‐free LPSM coating. Besides, the beef slices coated with CEO‐LPSM were the preferred samples in terms of sensory scores throughout the storage. Thus, using CEO‐rich LPSM edible coating might inhibit decay and significantly improve the shelf life of fresh beef.

Chitosan based coatings extend the shelf-life of beef slices during refrigerated storage

Chitosan is a food additive with antibacterial and antioxidant activities, ϵ-polylysine has antibacterial activity, and glutathione has potent antioxidant activity. This study aimed to investigate the effects of chitosan based coatings combined with ϵ-polylysine and glutathione (0.5% chitosan + 0.2% ϵ-polylysine + 0.1% glutathione) on preservation of beef slices during refrigerated storage. The beef slices treated with chitosan based coatings combined with ϵ-polylysine and glutathione had lower bacterial growth, pH value, total volatile basic nitrogen and thiobarbituric acid reactive substance values as well as higher red index and sensory quality than those of the control group during refrigerated storage. Treatment with chitosan based coatings combined with ϵ-polylysine and glutathione extended the shelf life of the treatment groups at least 6 days compared to the control group. The results indicated that chitosan based coatings combined with ϵ-polylysine and glutathione could be a promising method to extend the shelf-life of beef slices quality during refrigerated storage.

Method comparison between real-time spectral and laboratory based measurements of moisture content and CIELAB color pattern during dehydration of beef slices

In this study, partial least square (PLS) regression models were developed to predict moisture content (MC) (model 1), CIELAB color (model 2) or all four parameters (model 3) of beef slices during drying. Model development was based on data from two measurement campaigns of MC (%), CIELAB L*, a* and b*values and hyperspectral data in the range of 500–1009 nm. To increase the robustness of the models, the beef samples varied dependent on cattle breed, cut and pre-treatment. With low-cost, non-invasive continuous monitoring systems in mind, the models were simplified by wavelengths selection. The Deming and Passing-Bablok regression and the Bland-Altman plot revealed high model performances. Mean differences (full/reduced model) of −0.64/-0.64 for MC, −0.14/-0.15 for CIELAB L*, 0.05/0.04 for a* and 0.08/0.06 for b* values were achieved for model 3, which shows the high potential for simple real-time monitoring applications combining all investigated factors and parameters. • Robust models for spectral measurements of moisture and color during drying of beef. • High accordance between spectral and laboratory measurements. • Simplified high performance models by selection of maximum ten wavelengths. • High potential of simple non-invasive spectral monitoring systems for beef drying.

In vitro antimicrobial effects of Myristica fragrans essential oil on foodborne pathogens and its influence on beef quality during refrigerated storage

AbstractNutmeg (Myristica fragrans) seed was subjected to the hydro‐distillation method to extract its essential oil (NEO). Its main constituents were α‐pinene (20.16%), sabinene (14.45%), and β‐pinene (13.26%) with great antimicrobial and antioxidant actions. A novel edible coating was then fabricated based on the sage seed mucilage (SSM) and NEO, to ameliorate the quality and shelf‐life of beef slices. The NEO‐loaded SSM coating was able to significantly decrease the population of total viable count, Escherichia coli, Staphylococcus aureus, psychrotrophic bacteria, and fungi. Moreover, lipid oxidation of beef slices was remarkably suppressed upon the application of bioactive NEO‐loaded SSM edible coating, as compared with the control by Day 6. The coated beef sample, especially NEO‐rich SSM coated ones perceived a higher consumer acceptance and firmness than the SSM coated and noncoated samples. The SSM edible coating containing NEO could therefore have the potential to control the growth of pathogenic microorganisms and lipid oxidation, and to improve the color stability and sensory properties of meat and meat products.