Raw Beef Research Articles

Protective effects of sugarcane phenolic extract against lipid oxidative damages in raw ground pork and beef during refrigerated storage conditions

The study evaluated the bioactive components and antioxidant properties of sugarcane phenolic extracts (SCPE) against lipid oxidation in raw ground pork and beef during refrigerated storage conditions. Results showed that SCPE has a high total phenolic content of 35.9 g GAE/100 g sample majority of which are vanillic (799.77 mg/100 g), sinapic (434.38 mg/100 g), and coumaric (342.37 mg/100 g) acids. These phenolic compounds exhibited strong radical scavenging activities against DPPH (191.00 mg TE/g) and ABTS (359.80 mg TE/g) radical, ferric reducing capacity (97.80 mg TE/g), and lipid peroxidation inhibition (120.20 mg TE/g) activities which are comparable to BHT. Supplementation of SCPE at 400 mg/kg fresh weight of ground pork and ground beef improved the antioxidant activities of meat samples, leading to the delay in TBARS formation, lower reduction in heme iron content, and minimal increase in metmyoglobin content during 14-day refrigerated storage as compared to BHT-treated and control. Moreover, the redness of meat was preserved in SCPE- and BHT-treated samples as measured by a* color value. Correlation heat maps showed that TBARS, metmyoglobin, and ΔE are positively correlated with each other, and at the same time showed negatively correlated with heme iron and a*. This study revealed that antioxidant extracts from sugarcane presented a positive effect on the oxidative stability of raw ground pork and beef during refrigerated storage.

Comparative analysis of food heating techniques on purine release in beef

SummaryBeef is widely believed to be high in purines and should be restricted in the daily diet of hyperuricemia population. In this study, we measured and analysed the purines in beef which treated with several thermal techniques or their combination, including steam heating at 100 °C, 120 °C and 140 °C, microwave heating on low, medium and high fire, and infrared heating at 120 °C, 130 °C and 140 °C. In comparison with raw beef, steam heating at 100 °C (P < 0.0001), high fire microwaved heating (P < 0.0001), and infrared heating at 130 °C (P < 0.0001) reduced the total purine sharply, especially the uricogenic purines. And the superposition of steam heating such as SM (P = 0.002) and SI (P = 0.004) slightly decreased purine contents more than other combinations. Additionally, there were apparent differences in total purines upon the gastrointestinal digestion of processed beef. These provide a viable diet alternative for decreasing the purine contents in beef and which could be essential for managing high uric acid levels for hyperuricemia and gout.

Microbial Profiling of Biltong Processing Using Culture-Dependent and Culture-Independent Microbiome Analysis

Biltong is a South African air-dried beef product that does not have a heat lethality step, but rather relies on marinade chemistry (low pH from vinegar, ~2% salt, spices/pepper) in combination with drying at ambient temperature and low humidity to achieve microbial reduction during processing. Culture-dependent and culture-independent microbiome methodologies were used to determine the changes in the microbial community at each step during biltong processing through 8 days of drying. Culture-dependent analysis was conducted using agar-based methods to recover viable bacteria from each step in the biltong process that were identified with 16S rRNA PCR, sequencing, and BLAST searching of the NCBI nucleotide database. DNA was extracted from samples taken from the laboratory meat processing environment, biltong marinade, and beef samples at three stages of processing (post-marinade, day 4, and day 8). In all, 87 samples collected from two biltong trials with beef obtained from each of three separate meat processors (n = six trials) were amplified, sequenced with Illumina HiSeq, and evaluated with bioinformatic analysis for a culture-independent approach. Both culture-dependent and independent methodologies show a more diverse population of bacteria present on the vacuum-packaged chilled raw beef that reduces in diversity during biltong processing. The main genera present after processing were identified as Latilactobacillus sp., Lactococcus sp., and Carnobacterium sp. The high prevalence of these organisms is consistent with extended cold-storage of vacuum-packaged beef (from packers, to wholesalers, to end users), growth of psychrotrophs at refrigeration temperatures (Latilactobacillus sp., Carnobacterium sp.), and survival during biltong processing (Latilactobacillus sakei). The presence of these organisms on raw beef and their growth during conditions of beef storage appears to 'front-load' the raw beef with non-pathogenic organisms that are present at high levels leading into biltong processing. As shown in our prior study on the use of surrogate organisms, L. sakei is resistant to the biltong process (i.e., 2-log reduction), whereas Carnobacterium sp. demonstrated a 5-log reduction in the process; the recovery of either psychrotroph after biltong processing may be dependent on which was more prevalent on the raw beef. This phenomenon of psychrotrophic bloom during refrigerated storage of raw beef may result in a natural microbial suppression of mesophilic foodborne pathogens that are further reduced during biltong processing and contributes to the safety of this type of air-dried beef.

Foodborne disease hazards and burden in Ethiopia: A systematic literature review, 1990–2019

BackgroundFoodborne disease (FBD) affects millions of people each year, posing a health burden similar to malaria, tuberculosis or HIV. A recent World Bank study estimated the productivity losses alone attributed to unsafe food within Africa at $20 billion in 2016, and the cost of treating these illnesses at an additional $3.5 billion. Ethiopia faces multiple food safety challenges due to lack of infrastructure and basic pre-requisites for food safety such as clean water and environment, washing facilities, compounded by limited implementation of food safety regulations, and a lack of incentives for producers to improve food safety. A consolidation of our understanding and evidence of the source, nature and scale of FBD in Ethiopia is needed to inform policy and future research. We performed a Systematic Literature Review (SLR) of publications on FBD occurrence in Ethiopia including hazard presence and impact.MethodThe SLR followed Cochrane and PRISMA guidelines. We searched PubMed and CAB-Direct for relevant publications between 1990 and 2019 (inclusive). Observational studies and reviews were included. Two reviewers screened titles and abstracts, and retained publications were reviewed in full for quality and data extraction.ResultIn total 128 articles met the inclusion criteria. Most articles focused on the identification of biological hazards in food. High levels of microbial contamination in different food value chains were often found in the small,ad hoc, observational studies that dominated the literature. Raw milk (22/128, 17.0%) and raw beef (21/128, 16.4%) were the most studied food products. Foodborne (FB) parasites were often found at higher rates in food than bacterial and viral pathogens, possibly due to differences in ease of identification. High levels of bacterial contamination on the hands of food handlers were widely reported. There were no reports on the incidence of human FBDs or resulting health and economic impacts.ConclusionOur findings reflect existing concerns around food safety in Ethiopia. A lack of substantial, coordinated studies with robust methodologies means fundamental gaps remain in our knowledge of FBD in Ethiopia, particularly regarding FBD burden and impact. Greater investment in food safety is needed, with enhanced and coordinated research and interventions.

Characteristic flavor fingerprint disclosure of dzo beef in Tibet by applying SAFE-GC-O-MS and HS-GC-IMS technology

To understand the overall flavor of the dzo beef, fatty acids, volatile compounds and aroma profiles of dzo beef samples (raw beef (RB), broth (BT) and cooked beef (CB)) were investigated by head-space-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and gas chromatography-mass spectrometry (GC–MS). The fatty acid analysis showed a decrease in the ratio of polyunsaturated fatty acids, such as linoleic acid, which decreased from 2.60 % in RB to 0.51 % in CB. The principal component analysis (PCA) showed that HS-GC-IMS was able to distinguish different samples. A total of 19 characteristic compounds with odor activity value (OAV) > 1 were identified by gas chromatography–olfactometry (GC-O). Fruity, caramellic, fatty and fermented attributes were enhanced after stewing. Butyric acid and 4-methylphenol were responsible for the stronger off-odor in RB. 3-Hydroxy-2-butanone and 2,5-dimethyl-4-hydroxy-3(2H)-furanone with buttery and caramellic attributes were dominated in BT, while (E)-2-nonenal, (E,E)-2,4-decadienal and (E,E)-2,4-nonadienal prominently conferred fatty attribute on CB. Furthermore, anethole with anisic aroma was first identified in beef, which may be one of the typical chemical markers that distinguish dzo beef from other varieties.

Consumer preferences for the color of unprocessed animal foods.

Consumer choices for food products are often based on appearance; one important aspect being product color. We systematically review the literature on consumer preferences for the color of raw beef, pork, poultry, bee honey, cow milk, and chicken eggs to inform future food technology and marketing research; a total of 40 studies were identified. Consumer preferences for pork color vary widely globally and can depend on other demographic factors. A trend toward light and bright beef was observed in six out of eight studies. A pink color was preferred in chicken by consumers in Northern Ireland and Brazil; muscle color uniformity was also related to higher acceptance. Contrarily, a diverse selection of honey colors is preferred; dark golden, yellow, and amber products were liked by consumers across the globe. One study observed a preference for white (over yellowish) milk. Worldwide, white and brown eggshells are preferred nearly equally with considerable differences between continents and regions. Our review highlights the heterogeneity of color preferences for animal products, worldwide; research methods should focus on quantifying colors associated with preferences so that food producers can accurately market their diverse products in regions with corresponding color preferences.

Determination of Verification Parameters for Using the Manual Sampling Device for Fresh Raw Beef Trim

Multifaceted food safety systems are used by the beef processing industry to minimize risk of bacterial contamination of the finished product. These systems are comprised of several parts including the conditional release of product requiring a sample to produce a negative result on a pathogen test prior to sending the product into the food supply. The methods of sample collection require verification activities that ensure the sampling protocols are performed adequately. The research described herein was done to determine the parameters for use in verifying adequate beef trim sampling for the Manual Sampling Device (MSD) method. In addition, the efficacy of repeated sampling via multiple applications of the MSD procedure on a fresh raw beef trim combo was investigated. The results show that MSD sample collection thatcoversless than the entire combo surface, but at least one-halfof the combo surface and is collected for a minimum of 90 s, is adequate for the recovery of organisms and prevalence targets from fresh raw beef trim. In addition, the evidence that MSD sample collection thatoccurs forless than the recommended time, butnot less than 30 s per side of the swab, is adequate for the recovery of organisms and prevalence targets from raw beef trim. Finally, results show that in a scenario where an in-plant MSD sample and a regulatory MSD sample are required from the same combo, two MSD samples can be collected from the same combo bin with similar test results for both samples. While the recommended MSD protocol specifications will not be changed, the data presented herein provide support for some flexibility in accepting test results when verification activities indicate that sampling did not occur as specified in the recommended procedure.

Raw Beef Patty Analysis Using Near-Infrared Hyperspectral Imaging: Identification of Four Patty Categories

South African legislation regulates the classification/labelling and compositional specifications of raw beef patties, to combat processed meat fraud and to protect the consumer. A near-infrared hyperspectral imaging (NIR-HSI) system was investigated as an alternative authentication technique to the current destructive, time-consuming, labour-intensive and expensive methods. Eight hundred beef patties (ca. 100 g) were made and analysed to assess the potential of NIR-HSI to distinguish between the four patty categories (200 patties per category): premium 'ground patty'; regular 'burger patty'; 'value-burger/patty' and the 'econo-burger'/'budget'. Hyperspectral images were acquired with a HySpex SWIR-384 (short-wave infrared) imaging system using the Breeze® acquisition software, in the wavelength range of 952-2517 nm, after which the data was analysed using image analysis, multivariate techniques and machine learning algorithms. It was possible to distinguish between the four patty categories with accuracies ≥97%, indicating that NIR-HSI offers an accurate and reliable solution for the rapid identification and authentication of processed beef patties. Furthermore, this study has the potential of providing an alternative to the current authentication methods, thus contributing to the authenticity and fair-trade of processed meat products locally and internationally.

Novel sous-vide pressure technique affecting properties of local beef muscle

The low-temperature, long-time method of cooking known as sous-vide was used with increased pressure to enhance the tenderness and cook yield of local Thai beef round. The cooking was done in specialized equipment at 60 °C and 101, 200 or 300 kPa for 0–4 h. Beef treated with pressure was slightly lighter in color, and samples cooked for 2 h at 200 kPa had greater red saturation. Cooking at 200 kPa improved cook yield while reducing cook loss, with values of 78% after 4 h at 200–300 kPa versus 67% at 101 kPa. Cooking at 200–300 kPa resulted in more tender beef than at 101 kPa after 2 h. Sensory evaluation showed sous-vide pressure beef had higher ranking scores for tenderness and juiciness compared to control. SEM showed connective tissue of sous-vide pressure-cooked beef was diffuse and with looser muscle fibers than boiled or raw beef. Electrophoretic profiles showed that thick and thin filament bands decreased with cooking time. However, myosin heavy chain was sensitive to both heat and pressure. Reducing conditions showed pressure and heat induced disulfide bonding. Studies by FTIR showed cooking at 200 kPa caused the greatest decrease in α-helix content and increase in β-structures than non-treated and boiled beef.

Prevalence and characterization of quinolone-resistant Escherichia coli isolated from retail raw beef and poultry meat in Egypt.

The goal of this study was to look at quinolone-resistant (QR) Escherichia coli (E. coli) from retail beef and poultry meat in Egypt by looking at the QR mechanisms in the resistant strains. In total, 120 samples of raw poultry meat (n = 60) and beef meat (n = 60) were purchased from Mansoura retail stores between January and March 2021, and evaluated microbiologically for E. coli. Then, an antimicrobial sensitivity test was applied to all isolates. The prevalence of QR E. coli with concern for the QR determinants, including quinolone resistance-determining regions (QRDRs) mutations, the plasmid-mediated quinolone resistance gene (PMQR), and the efflux pump activity were determined. The total prevalence of E. coli was 34.2% (41/120). Noticeably, the prevalence of E. coli in poultry meat (40%, 24/60) was higher than that of beef (28%, 17/60). All strains were assessed for their antimicrobial susceptibility using the disc diffusion technique; the highest rate of resistance (100%) was displayed to clindamycin and cefuroxime, followed by ampicillin (97.6%), doxycycline (92.7%), amoxicillin-clavulanate (92.7%), nalidixic acid (NA) (80.5%), sulfamethoxazole/trimethoprim (70.7%), chloramphenicol (63.4%), gentamicin, and azithromycin (58.5% each). Multiple antimicrobial resistance (strains resistant to three or more antimicrobial classes) was displayed by 97.6% of E. coli isolates. Regarding QR, 37 isolates could resist at least one of the examined quinolones. Regarding PMQR genes, qnrS was determined in 70% (7/10) of QR E. coli, while qnrA, qnrB, and qnrD were not identified. While the mutations determined regions of QR in the resistant E. coli isolates, S83L was the most prevalent in gyrase subunit A either alone or combined with D87N and D87Y, and three isolates of QR E. coli isolates revealed a topoisomerase IV subunit mutation harboring S80I. 20% of the isolates displayed efflux activity, as NA showed a considerable difference between its zones of inhibition. The high prevalence of antimicrobial-resistant E. coli, with concern for QR strains harboring different resistance mechanisms in poultry meat and beef, threatens the public's health. Thus, standard manufacturing procedures and adequate hygiene conditions must be followed in all phases of meat preparation, production, and consumption, and public knowledge should be improved.

Gelatin/carboxymethyl cellulose edible films: modification of physical properties by different hydrocolloids and application in beef preservation in combination with shallot waste powder.

In this work, a gelatin/carboxymethyl cellulose (CMC) base formulation was first modified by using different hydrocolloids like oxidized starch (1404), hydroxypropyl starch (1440), locust bean gum, xanthan gum, and guar gum. The properties of modified films were characterized using SEM, FT-IR, XRD and TGA-DSC before selecting of best-modified film for further development with shallot waste powder. SEM images showed that the rough or heterogeneous surface of the base was changed to more even and smooth depending on the hydrocolloids used while FTIR results demonstrated that a new NCO functional group non-existent in the base formulation was found for most of the modified films, implying that the modification led to the formation of this functional group. Compared to other hydrocolloids, the addition of guar gum into the gelatin/CMC base has improved its properties such as better color appearance, higher stability, and less weight loss during thermal degradation, and had minimal effect on the structure of resulting films. Subsequently, the incorporation of spray-dried shallot peel powder into gelatin/CMC/guar gum was conducted to investigate the applicability of edible films in the preservation of raw beef. Antibacterial activity assays revealed that the films can inhibit and kill both Gram-positive and Gram-negative bacteria as well as fungi. It is noteworthy that the addition of 0.5% shallot powder not only effectively decelerated the microbial growth but also destroyed E. coli during 11 days of storage (2.8 log CFU g-1) and the bacterial count was even lower than that of uncoated raw beef on day 0 (3.3 log CFU g-1).

Coliform Contamination of Raw Beef at the Slaughterhouse and Butchery Levels in Herat City, Afghanistan

Background: Contaminated food products are responsible for causing various food borne diseases all over the world. Microbial contaminants are present in various food products, particularly raw meat. Among the most common microbial contaminants in meat and meat products are coliform bacteria. This study aimed to determine the coliform quality of raw beef with special emphasis on Escherichia coli in Herat city, Afghanistan and to compare the coliform contamination levels in the slaughterhouse and butchery levels. Materials and Methods: In this study, 150 samples of raw beef were randomly selected from butcheries and slaughterhouses of Herat city. Coliform identification was performed by standard bacteriological methods. Findings: The findings of this study revealed that coliform bacteria were detected in 70% and 75 % of beef samples from slaughterhouses and butcheries respectively. A total of 58 % of positive samples were upon the standard accepted ratio of coliforms contaminant per gram. The E. coli contamination ratio of samples in slaughterhouses and butcheries were 52% and 72% respectively. Our study demonstrates a significant difference in coliform bacteria contamination between slaughterhouse samples and butcheries. Conclusion: It was concluded that more than half of the coliform contamination in raw beef from the slaughterhouse and butcheries was exceeded the maximum limit which highlights the need to focus on effective monitoring of the slaughterhouse and butcheries in Herat city for prevention of meat borne intoxication and infection.

Molecular detection of methicillin-resistant Staphylococcus aureus isolated from different foodstuffs in Egypt.

Methicillin-resistant Staphylococcus aureus (MRSA) infection is a major public health problem. Therefore, this study was aimed to estimate the prevalence of MRSA in various food products. A total number of 204 food samples including raw milk (n = 30), cheese (n = 60), chicken (n = 25), beef (n = 24) and fish (n = 65) were collected from August to November of 2021 within different localities in Kafr El-Sheikh governorate, the northern region of Egypt. All samples were assessed through a series of bacteriological and biochemical techniques to identify MRSA. Out of 204 samples, 52(25.49%) isolates were presumptively identified as MRSA on oxacillin resistance screening agar base media. Of these 52 isolates, 17(32.69%) were characterized as coagulase-positive. For the molecular confirmation of MRSA, all isolates were subjected to polymerase chain reaction assays to detect mecA and mecC. In addition, mecA was identified in all the isolates (100%), whereas, none was positive for mecC. Therefore, based on the detection of mecA, the overall occurrence rate of MRSA among the samples was 8.33%. The isolates were also subjected to antimicrobial susceptibility tests. Cefoxitin, cefuroxime, oxacillin and amoxicillin-clavulanic acid were completely resistant (100%) to the isolates, however, susceptible to vancomycin and ciprofloxacin. Raw milk had the highest prevalence of MRSA (13.30%), followed by chicken (12.00%), fish (9.20%), cheese (5.00%) and beef (4.20%). Due tothe possibility of transmission of these strains to humans, the high prevalence of MRSA in various foodstuffs in Egypt poses a potential public health risk.

Development, Characterization and Investigation of Antimicrobial and Antioxidant Potential of Sodium Caseinate-Based Edible Films Infused with Berberis pseudumbellata Fruit Extract, and Effects of the Films on the Quality of Raw Ground Beef During Refrigeration

Development, Characterization and Investigation of Antimicrobial and Antioxidant Potential of Sodium Caseinate-Based Edible Films Infused with <i>Berberis pseudumbellata</i> Fruit Extract, and Effects of the Films on the Quality of Raw Ground Beef During Refrigeration

Tracing models for checking beef adulterated with pig blood by Fourier transform near-infrared paired with linear and nonlinear chemometrics

Faced with the aggravating issue of meat fraud caused by the addition of low-cost animal blood food, the present work aims to develop FT-NIR-based tracing models for detecting beef adulterated with pig blood. A total of 210 samples were analyzed, including raw beef, beef adulterated with pig blood-based gel, and pure pig blood-based gel prepared. For spectrum denoising, the first derivative, second derivative, centralization, standard normal variate transform, and multivariate scattering correction algorithms were performed and compared. We built, optimized, and compared partial least squares (PLS), support vector machine (SVM), and extreme learning machine (ELM) models for identifying the adulterated beef and predicting adulteration levels. Results indicated that second derivative was the best preprocessed technique for all chemometrics modeling; ELM model achieved the optimal performance when the sin function was used, achieving 100% accuracy for identifying the adulterated beef, and all root mean square errors were less than 0.16% for predicting adulteration levels in training and test sets. These results suggest the optimal ELM models could be employed for rapidly checking beef adulterated with pig blood-based gel using FT-NIR technology.

Modified, innovative method for detection of adulteration of meat pro­ducts with meat of other species

The aim of this study was to detect illegal adulteration of beef meat products with meat from other species. Samples (n=120) of industrial and handmade beef products were randomly collected from retail outlets in Assiut city, Egypt: raw beef burger, oriental beef sausage, beef kofta, and beef luncheon (30 samples each). Samples were analysed using agar gel immunodiffusion (AGID) and modified AGID (MAGID) assays. Results showed that 17.5% of examined products were adulterated with chicken meat. MAGID detected that 14.1% of samples were adulterated with donkey meat, whereas all AGID results were negative. Human tissue was detected in 8.3% (AGID) and 10% (MAGID) of examined samples. Histological examination was then used to detect foreign tissue, and all categories of products were found to be adulterated, and some of them - contaminated with human blood cells. Polymerase chain reaction analysis confirmed that MAGID was more accurate and sensitive than AGID, especially for false negative AGID results. Consumers are advised not to consume too much of the studied meat products to avoid exposure to adulterated or contaminated products that might constitute a health hazard.

Antimicrobial Susceptibility Pattern of Enterohaemorrhagic Escherichia coli (EHEC O157:H7) in Raw Beef samples collected from abattoirs and Meat Vendors in Ile Ife and its environs, South-West, Nigeria

Nigeria bears a large burden of foodborne diseases in Africa, and the second leading causes of premature deaths in Africa is linked to diarrheal diseases. Enterohemorrhagic Escherichia coli O157 (EHEC O157:H7) causes an asymptomatic infection to severe diarrhea and/or hemolytic-uremic syndrome in humans which are serious health conditions that calls for serious health concern. The present investigation was done to study the prevalence and antibiotic resistance of Enterohaemorrhagic Escherichia coli O157:H7 strains isolated from raw meat samples. Raw beef samples were collected from abattoirs and retail outlets in three local government areas (LGAs) in Ile- Ife axis namely: Ife North, Ife Central and Ife East for isolation and identification of EHEC O157:H7. Standard microbiological methods were used to isolate and identify EHEC O157:H7 and antibiotics susceptibility pattern was carried out on the isolates to determine their susceptibility or otherwise. EHEC O157 was detected in 16% of meat samples from Abbatoirs slabs and 33% from meat vendors and retailers. EHEC O157 was not detected in one of the beef samples obtained from a particular Abbatoir. The EHEC O157:H7 isolates were found to be most susceptible to meropenem (91.50%) followed by vancomycin (90.80%) and ceftazidime (88.8%). Isolates were found to be most resistant to ampicillin (90.85%), followed by chloramphenicol (86.93%) and cefixime (85.63%). Furthermore, isolates were resistant to a range of more than five antibiotics and three classes of antibiotics, depicting multi drug resistance pattern. Five isolates were resistant to ampicillin, two isolates to streptomycin and three isolates to chloramphenicol. One isolate was resistant to two drugs and another to three drugs. The present study shows a bit higher prevalence of EHEC O157 in beef sold directly at abattoirs. Considering, the high infective dose of this pathogen and the deep-rooted tradition of consuming raw or undercooked beef, the current prevalence should not be considered lightly from a public health perspective.

Integration of Non-targeted Proteomics Mass Spectrometry with Machine Learning for Screening Cooked Beef Adulterated Samples

The degradation of ingredients in heat-processed meat products makes their authentication challenging. In this study, protein profiles of raw beef, chicken, duck, pork, and binary simulated adulterated beef samples (chicken-beef, duck-beef, and pork-beef) and their heat-processed samples were obtained by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Heat-stable characteristic proteins were found by screening the overlapping characteristic protein ion peaks of the raw and corresponding heat-processed samples, which were discovered by partial least-squares discriminant analysis. Based on the 36 heat-stable characteristic proteins, qualitative classification for the raw and heat-processed meats was achieved by extreme gradient boosting. Moreover, quantitative analysis via partial least squares regression was applied to determine the adulteration ratio of the simulated adulterated beef samples. The validity of the approach was confirmed by a blind test with the mean accuracy of 97.4%. The limit of detection and limit of quantification of this method were determined to be 5 and 8%, respectively, showing its practical aspect for the beef authentication.

Kappa-carrageenan-poly(vinyl alcohol) electrospun fiber mats encapsulated with Prunus domestica anthocyanins and epigallocatechin gallate to monitor the freshness and enhance the shelf-life quality of minced beef meat

The current study was conducted with the aim of fabricating k-carrageenan-poly(vinyl alcohol) (KC-PVA) electrospun fiber mats containing Prunus domestica extract (PDE; 3%) and epigallocatechin gallate (EGCG; 5 and 10 µg/ml) to monitor the spoilage and enhance the shelf-life quality of raw minced beef meat during prolonged chilled storage. The anthocyanin-rich electrospun fibers displayed color change when subjected to the different pH buffer solutions as follows: pH 1 = light pink; pH 2-5 = red; pH 6-8 = purplish-red; pH 9-10 = green; and pH 11-12 = brown. By incorporating PDE and PDE + EGCG into the KC-PVA electrospun fibers, tensile strength, water vapor permeability, moisture content, and water solubility decreased significantly, while thickness and elongation at break increased significantly compared to the control group (P < 0.05). Among different treatments, the lowest microbial and chemical changes and the highest sensory scores were found in the minced beef meat packaged with KC-PVA-EGCG 5 µg/ml-PDE 3% and KC-PVA-EGCG 10 µg/ml-PDE 3% electrospun fibers. At the end of the study (day 15), the total viable count, pH, and total volatile basic nitrogen of samples packaged with KC-PVA-PDE 3% electrospun fibers reached 7.21 log CFU/g, 6.63, and 28.07 mg N/100 g, respectively. In this group, the color of the electrospun fiber mats changed from white to purplish-red. Our findings indicate that the fabricated electrospun fibers with antimicrobial and antioxidant activities can be utilized as a smart packaging material for minced beef meat during refrigerated storage.

Effect of freezing raw meat on the physicochemical characteristics of beef jerky

The effect of freezing raw meat on the quality characteristics of beef jerky was evaluated in the present study. Jerky was made using different types of raw beef (fresh, frozen, and frozen-thawed) with different curing times (6 h and 12 h). Frozen-thawed beef had a lower moisture content than fresh or frozen beef due to higher exudate loss (P < 0.05). Jerky made using frozen and frozen-thawed beef showed lower drying yield and higher shear force than jerky prepared using fresh beef (P < 0.05). Freezing raw beef decreased the fat content and increased the redness, yellowness, chroma, and hue values of jerky (P < 0.05). The microstructure of beef jerky was showed to increase the deformation and contraction of muscle fibers due to freezing. Longer curing times increased the moisture content of jerky made using frozen meat (P < 0.05). Jerky made using frozen or frozen-thawed meat was tough due to excessive fat and moisture loss.