Beef Burger Samples Research Articles

COMPARATIVE STUDY BETWEEN THE EFFECT OF GAMMA IRRADIATION AND OZONE GAS ON THE INCIDENCE OF E. COLI O157:H7 IN BEEF BURGER SOLD IN ASSIUT GOVERNORATE

This study aimed to determine the prevalence of E. coli O157:H7 in beef burger, evaluate the effectiveness of gamma irradiation and ozone gas as an antimicrobial intervention on beef burger and evaluate the effect of both on sensory quality of the product. A total of 125 samples of beef burger were collected from different supermarkets in Assiut City, E .coli was isolated from 24 samples (19.2%), further examination using polymemerase chain reaction (PCR) revealed that only one confirmed to be E. coli O157:H7 with a percentage of 0.8%. Beef burgers inoculated with E. coli O157:H7 at initial level of 106 CFU/g were exposed to different doses of ƴ- radiation (2,4 and 6 KGy) at dose rate 2.32 KGy/h at a constant exposure time. The survival of E. coli O157:H7 was examined post treatments. Irradiation at doses (4 and 6 KGy) significantly decreased the count proportionally to the applied dose without any sensory changes. To explore the effect of ozone on E. coli O157:H7, inculcated samples of beef burger were subjected to 3 different gaseous ozone treatments, 20, 40 and 70 PPM with a time of contact of approximately 3 minutes. It was found that all concentrations significantly reduced the pathogen count without any color or flavor change of beef burger. Gamma irradiation at dose 6KGy is more effective in reduction of E. coli O157:H7 population (a reduction % of 56.o8) than ozone gas at concentration of 70 PPM (a reduction % of 21.14).The public health importance of the organism was discussed and the suggestive measures for safe healthful products were discussed.

DETECTION OF SALMONELLAE IN SOME MEAT PRODUCTS

A total of 150 samples of meat products (34 sausage, 35 beef burger, 39 minced meat and 42 luncheon samples) were collected randomly from different markets at Kafr-El-sheikh and El-Gharbiah governorates on Egypt .the samples were examined for isolation and identification of Salmonella Spp.. The PCR results showed that salmonella Spp were detected in 4 (11.8 %), 1(2.9%), 2 (5.1%) samples of examined sausage, beef burger and minced meat samples, respectively and not detected in luncheon samples. The isolated salmonellae were S. kentucky, S.saintpaul and S.tounouma in sausage samples, S.liverpool in beef burger samples and S. muenster and S. hadar in minced meat samples. These results showed that sausage, beef burger and minced meat might represent a source for salmonella as a food borne disease for human being.

Prevalence, molecular identification and antimicrobial resistance profile of Salmonella serovars isolated from retail beef products in Mansoura, Egypt

The present study was undertaken to determine the prevalence of Salmonella in 270 raw meat samples (90 each of fresh beef, ground beef, and beef burger) purchased on nine occasions from various supermarkets and butchers' shops in Mansoura city, Egypt. Using conventional biochemical identification, Salmonella species were recovered from 23.3% (21/90), 20% (18/90), and 12.2% (11/90) of fresh beef, ground beef and beef burger samples, respectively with an overall prevalence of 18.5% (50/270) among all the meat products examined. Higher prevalence were obtained based on molecular identification, by detecting gyrB and invA genes, which verified the presence of Salmonella species in 30.0% (27/90), 26.7% (24/90), and 16.7% (15/90) of fresh beef, ground beef, and beef burger samples, respectively with an overall prevalence of 24.4% (66/270) among all the meat products tested. Of the 2635 presumptive colonies tested, 228 were biochemically identified as Salmonella, while 272 were molecularly identified as Salmonella, which were all positive for the enterotoxin (stn) virulent gene. Of the 272 serologically tested strains, 266 were serologically identified into six Salmonella serovars, while 6 strains were untypable. Salmonella Typhimurium and Salmonella Enteritidis were the most prevalent serovars with an incidence of 38.2% (104/272) and 34.6% (94/272), respectively. The other four serovars identified were Salmonella Haifa, Salmonella Muenster, Salmonella Virchow, and Salmonella Anatum were detected at lower prevalences of 11% (30/272), 7.4% (20/272), 4% (11/272) and 2.6% (7/272), respectively. Interestingly, the antimicrobial susceptibility testing indicated that all of the 100 Salmonella serovars tested were multidrug resistant (resistant to three or more antibiotics). Our findings demonstrated that the retail beef products tested were widely contaminated with multidrug-resistant Salmonella and such contamination may constitute a major public health concern.

Occurrence, serotypes and virulence genes of non-O157 Shiga toxin-producing Escherichia coli in fresh beef, ground beef, and beef burger

This study determined the prevalence, serotypes and virulence genes distribution of non-O157 Shiga toxin-producing Escherichia coli in meat products collected from butchers shops and supermarkets in Mansoura city, Egypt. We have characterized 18 non-O157 STEC strains among the identified 100 E. coli isolates recovered from the examined 87 meat product samples. The prevalence of non-O157 STEC strains in fresh beef, ground beef and beef burger samples were 11.1% (3/27), 16.7% (5/30), and 33.3% (10/30), respectively. The eighteen non-O157 STEC isolated strains were serotyped into seven (38.9%) O111:H8, six (33.3%) O26:H11, two (11.1%) O111:H–, and one (5.56%) for each of O55:H7, O126:H5 and O128:H2. PCR assays for different virulence genes showed that nine (50%), eleven (61.1%), and nine (50%) strains carry stx1, stx2, and eae genes, respectively. The distribution of shiga toxin genes among the isolated strains indicated that seven (38.9%) strains harbored stx1 only, nine (50%) strains harbored stx2 only, and two (11.1%) strains harbored both stx1 and stx2. The eae gene was present in association with five (27.8%), three (16.7%), and one (5.6%) strains that harbored stx1 only, stx2 only, and both stx1 and stx2, respectively. This study concluded that the examined meat products, particularly beef burger, consumed in Egypt are considerably contaminated with a variety of non-O157 STEC serotypes, and hence consumption of such products may constitute a potential health risk for consumers.

Detection of Offal Adulteration in Beefburgers Using near Infrared Reflectance Spectroscopy and Multivariate Modelling

The main aim of this study was to develop a rapid and reliable tool using near infrared (NIR) reflectance spectroscopy to confirm beefburger authenticity in the context of offal (kidney, liver, heart and lung) adulteration. An experimental design was used to develop beef burger formulations to simultaneously maximise the variable space describing offal-adulterated samples and minimise the number of experiments required. Authentic ( n = 36) and adulterated ( n = 46) beefburger samples were produced using these formulations. Classification models (partial least squares discriminant analysis, PLS1-DA) and class-modelling tools (soft independent modelling of class analogy, SIMCA), were developed using raw and pre-treated NIR reflectance spectra (850–1098nm wavelength range) to detect authentic and adulterated beefburgers in (1) fresh, (2) frozen-then-thawed and (3) fresh or frozen-then-thawed states. In the case of authentic samples, the best PLS1-DA models achieved 100% correct classification for fresh, frozen-then-thawed and fresh or frozen-then-thawed samples. SIMCA models correctly identified all the fresh samples but not all the frozen-then-thawed and fresh or frozen-then-thawed samples. For the adulterated samples, PLS1-DA models correctly classified 95.5% of fresh, 91.3% of frozen-then-thawed and 88.9% of fresh or frozen-then-thawed beefburgers. SIMCA models exhibited specificity values of 1 for both fresh and frozen-then-thawed samples, 0.99 for fresh or frozen-then-thawed samples; sensitivity values of 1, 0.88 and 0.97 were obtained for fresh, frozen-then-thawed and fresh or frozen-then-thawed products, respectively. Quantitative models (PLS1 regression) using both 850–1098nm and 1100–2498 nm wavelength ranges were developed to quantify (1) offal adulteration and (2) added fat in adulterated beefburgers, both fresh and frozen-then-thawed. Models predicted added fat in fresh samples with acceptable accuracy ( RMSECV=2.0; RPD=5.9); usefully accurate predictions of added fat in frozen-then-thawed samples were not obtained nor was prediction of total offal possible in either sample form.

Efeito de extratos de caqui (Diospyros kaki L.) cultivar Rama Forte e do extrato oleoso de alecrim (Rosmarinus officinalis L.) nas características sensoriais e na estabilidade da cor de hambúrguer de carne bovina congelado

This study aimed to evaluate the effect of the extract of persimmon cv. ‘Rama Forte’ and rosemary oily extract on the sensory characteristics and color stability of frozen beef burgers. The crude hydroethanolic extract was prepared and subjected to fractionation resulting in the hexane, chloroform and ethyl acetate fractions as well as residual fraction. For the preparation of the burger samples a basic formulation was prepared and divided into parts: control, standard formulation ( 0.1% of sodium erythorbate), treatment 1 (0.5% of hydroethanolic crude extract), treatment 2 (0.7% of hydroethanolic crude extract), treatment 3 (0.5% of the residual fraction), treatment 4 (0.7% of the residual fraction ) , treatment 5 ( 0.5% of ethyl acetate fraction), Treatment 6 (0.7% of ethyl acetate fraction) and treatment 7 (0.10% of oily extract of rosemary). The beef burger samples were stored at-25° C for 14 months and subjected to sensory analysis (color, aroma, flavor, and texture) at the beginning of the experiment and the measurement of color (parameters L a*, b* and h*) every two months. The addition of the extracts did not promote changes in the sensory attributes of the beef burgers at time zero of storage. A tendency to decrease a* values and increase of the h* values of the samples of frozen beef burgers occurred over the period of storage. Samples added with ethyl acetate fraction (0.5 and 0.7%) and the oily extract of rosemary showed higher a* values than the other samples throughout the storage period and lower h* values than the standard sample at the end of the period evaluated. This indicates that the addition of ethyl acetate fraction and rosemary extract contributed to the retention and stability of the red color of the samples of beef burgers during the storage of the frozen product.

Detailed evaluation of a newly attained fungal pigment from Monascus purpureus in meat burgers

Beef burgers with red pigment extracted from Monascus purpureus, used as a natural colouring agent, were examined for chemical compositions, physical properties, microbiological aspects and organoleptic evaluation. Beef burgers with Monascus pigment showed higher nutritional values compared with control samples. Nutritional values were proportionally enhanced by increasing pigment concentration. Synthetic dye samples had the lowest values of nutrients. Cooking loss percentage and water holding capacity were lower in all treatments compared with control samples, and vice versa for plasticity. The initial total bacterial count, Staphylococcus aureus count and coliform count were determined. Extending storage period up to 90 days severely reduced all tested microorganisms. By increasing the M. pigment concentration, the colour was significantly increased. Insignificant differences in colours were noticed among various treatments. Flavour and body and texture scores were insignificantly different. Microbial inhibition percentage of beef burger samples was increased by increasing the Monascus pigment concentration up to 0.8 g/kg.

The rapid detection of E. coli 0157 Antigen in meat products by using ELISA Test Kit

This study was conducted for rapid detection of contamination of meat products with E. coli 0157 by usage of ELISA test kit as one of the most rapid and newest test. The study showed the efficiency of ELISA test kit used in this study in detection of bacteria antigen in meat products samples of raw beef meat , kabab and beef burger which subjected to improper storage conditions or undercooked and hence when some peoples uptake some of these products they suffered from clinical intoxication signs like diarrhea ,vomiting and hyperthermia. The kit showed the presence of (9) samples positive among (90) samples ; (2) positive out of (30) kabab samples,(3) positive out of (30) beef burger and (4) positive out of (30) raw beef meat after 16 hrs of enrichment of all samples in EC Modified broth including Novobiocin supplement as inhibitor of other bacteria and then the liquid supernatants from all prepared samples got tested by ELISA kit used in this study and the data recovered in less than 1 hr.The study indicated the ability of using ELISA kit for detection of E. coli 0157 antigens in food stuffs and reduce the time for releasing the results in less than 24 hrs when compared with conventional culturing procedure which reuiqred more than 3 days and launch the food products for consumption with focusing on the main point here which is the protection of our consumer safety.

DETERMINATION OF CHEMICAL PARAMETERS OF BEEF AND ITS PRODUCTS

A total of 120 samples of frozen beef and its products (beef burger, kofta and sausage), 30 samples of each, were collected from different supermarkets in Alexandria governorate to evaluate their chemical quality. The results revealed that the highest mean total volatile nitrogen (TVN) (25.688 mg/ 100gm) was found in sausage samples while the lowest (19.456 mg/100gm) was in frozen beef meat samples. Concerning pH, beef burger samples showed the highest mean levels (6. 130) while frozen beef samples had the lowest (6.088). In case of acid value, sausage had the highest mean concentration (1.149 mgkoH /gm of fat) while, frozen beef samples showed the lowest value (1.130 mgkoH /gm). Rgarding free fatty acids, the highest mean concentration (0.750ml/gm) was found in sausage while the lowest (0.565 ml /gm) was in frozen beef samples. In case of conjugated dienes (CD), the highest level (0.069 n mole/mg) was in sausage samples while the lowest (0.041 n mole/mg) was in frozen beef. Concerning thiobarbeturic acid value (TBA), sausage also showed the highest level (0.901 mg malonaldhyde /kg of sample) while frozen beef samples showed the lowest (0.7018 mg malonaldhyde /kg of sample).

Beef burger patties incorporated with Boletus edulis extracts: Lipid peroxidation inhibition effects

The objective of this study was to analyse the lipid peroxidation inhibition in beef burgers after incorporation of Boletus edulis extracts at different concentrations. Beef burger samples were stored for 8 days, and chemical and nutritional parameters, including the free fatty acid profile, were evaluated. Furthermore, the inhibition of thiobarbituric acid reactive substances (TBARS) formation, free radical scavenging activity and reducing power were determined. Polyunsaturated fatty acids, mainly arachidonic (C20:4n6) and cis-5,8,11,14,17-eicosapentaenoic (C20:5n3) acids were protected in the presence of mushroom extract. The antioxidant potential increased in beef burgers supplemented with mushroom extract, giving higher radical scavenging properties, reducing power and TBARS inhibition capacity. These findings indicated that beef burger patties were protected from lipid peroxidation in the presence of mushroom extract.

BACTERIOLOGICAL ASSESSMENT OF SOME READY-TO-EAT FOODS

A total of sixty random samples of grilled chicken, chicken luncheon, beef shawerma, beef burger, yoghurt and veta cheese (10 samples of each) were collected from different cafeterias in Giza Governorate and examined bacteriologically. Our study revealed presence of E. coli by ratio of 20%, 10%, 10%, 20% 10% and zero% in the examined samples of grilled chicken, chicken luncheon, beef shawerma, beef burger, yoghourt and veta cheese respectively. Whereas Salmonella spp. were not detected, but Staph aureus spp. were detected by ratio of 40%, 10%, 20%, 30%, 20% and 20%, respectively in the examined samples. While mean Yerisina were detected by ratio of 10% in each of grilled chicken, beef shawerma and beef burger samples but failed to be detected from the examined samples of chicken luncheon, yoghourt and veta cheese samples.This study determined aerobic plate count, enterobacterial count, Bacillus cereus count and Staph aureus count in the examined samples.

Utilization of hazelnut pellicle in low-fat beef burgers

Hazelnut pellicle was used as a dietary fiber in the production of beef burgers. The effects of hazelnut pellicle addition on proximate composition, pH, cook loss, dimensional changes, color and sensory characteristics of beef burgers were evaluated. Hazelnut pellicle addition affected some quality parameters of beef burgers. The control samples had the lowest moisture and protein contents ( P < 0.05). The cooking yield and reduction in diameter and thickness of beef burgers improved by the addition of hazelnut pellicle. Beef burgers formulated with hazelnut pellicle had lower L, a and b values than control samples ( P < 0.05). There were differences among beef burger samples in respect to sensory properties, control samples and 1% and 2% pellicle added samples had high acceptability. The results indicate that, 1–2% hazelnut pellicle can be used as a suitable dietary fiber source in low-fat beef burger production.

A survey of the prevalence of Escherichia coli O157 in raw meats, raw cow's milk and raw-milk cheeses in south-east Scotland

2429 samples of foodstuffs were examined for the presence of verocytotoxigenic Escherichia coli O157 (VTEC O157) by means of immunomagnetic separation (IMS) over a 2-year period commencing April 1997. Specimens comprised 1190 raw meats, 500 raw milks and 739 raw-milk cheeses. The meat and cheese samples were purchased from retail premises in south-east Scotland; raw milk samples were obtained directly from farms. In addition, total E. coli counts were performed on milk and cheese samples, and the pH of cheese specimens measured. The water activity ( A w) was also measured for a representative sample of each cheese type, and for all of the samples with high levels of E. coli. VTEC O157 was isolated from two samples of beef burger, both manufactured on the premises of the same butchers shop. Control studies with artificially inoculated foodstuffs demonstrated a sensitivity of detection of <5 organisms 25 g −1. These findings, which contrast with the results of similar studies elsewhere in the UK, suggest that other sources of infection may be important in explaining the high rates of infection with this organism in south-east Scotland.

Occurrence of aflatoxins and aflatoxin‐producing moulds in fresh and processed meat in Egypt

A survey was carried out to detect aflatoxins and isolate aflatoxigenic moulds contaminating fresh and processed meat products. The fungal contamination was examined in 215 samples of fresh and processed meat products and 130 samples of spices used in the meat industry collected from different local companies in Cairo, Egypt. Processed meat products such as beefburger, hot-dog, kubeba, sausage, luncheon meat had the highest count of moulds as compared with fresh and canned meat. Out of 150 samples of meat products and 100 samples of spices, aflatoxin B1 was detected in five samples of beefburger, (8 micrograms/kg), four samples of black pepper (35 micrograms/kg), and four samples of white pepper (22 micrograms/kg). Aflatoxins B1 and B2 were detected in one sample of kubeba (150 micrograms B1/kg and 25 micrograms B2/kg); hot-dog (5 micrograms B1/kg and 2 micrograms B2/kg) sausage (7 micrograms B1/kg and 3 micrograms B2/kg) and luncheon meat (4 micrograms B1/kg and 2 micrograms B2/kg). Also, aflatoxins B1 and G1 were detected in two samples of turmeric (12 micrograms B1/kg and 8 micrograms G1/kg) and coriander (8 micrograms B1/kg and 2 micrograms G1/kg). Aspergillus flavus (24 isolates), and Aspergillus parasiticus (16 isolates) were the predominant aflatoxin-producing moulds isolated from both processed meat products and spices. Aflatoxins were absent in fresh meat, canned meat, salami, beefsteak and minced meat. The contamination of processed meat with aflatoxin was shown to correlate with the addition of spices to fresh meat.