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Molecular study of Clostridium difficile isolated from beef in Isfahan, Iran
2016
Esfandiari, Zahra | Jalali, Mohammad | Ezzatpanah, hamid | Weese, Scott | Chamani, Mohammad | Shoaei, Parisa | Yaran, Majid | Ataei, Behrooz
BACKGROUND: Clostridium difficile (C. difficile) infection is one of the most important diseases in healthcare facilities and community. Ribotypes 027 and 078 are known as hyper-virulent strain of C. difficile in molecular study. PCR-ribotyping is a suitable method to interpret the relation of C. difficile isolated from food and hospital. Objectives: In the present study, the clostridim difficile binary toxin (cdtB) and ribotype pattern evaluated in toxigenic C. difficle isolated from beef. Methods: Detection of cdtB in 12 toxigenic C. difficile (encoding tcdA and tcdB gene) isolated from 100 beef samples was determined through PCR. Afterwards, PCR-ribotyping was performed to examine the ribotype patterns of C. difficile. Results: cdtB gene was not detected in any positive isolate. Ten different patterns were observed in 12 toxigenic isolates. No similarity existed in the ribotypes of our study with ribotypes 027 and 078. Conclusions: Albeit ribotyp 027 and 078 were not found in our study, the isolation of toxigenic C. difficile with new ribotypes in Iran may indicate the probable hazard of this bacterium in public health. Comprehensive research about C. difficile in different food sources is recommended on a national level.
显示更多 [+] 显示较少 [-]Influence of post-mortem muscle glycogen content on the quality of beef during aging
2016
Onopiuk Anna | Półtorak Andrzej | Wierzbicka Agnieszka
Introduction: Glycolic changes which occur post-mortem have an impact on the physical and sensory features of beef, which in turn determine the successive processes and influence such beef quality traits as colour, tenderness, and cooling loss. The aim of this study was evaluation of the post-mortem changes in bovine meat during aging, quantitative analysis of glycogen and lactic acid, as well as examination of their impact on technological and sensory quality of selected muscles from Holstein-Friesian × Limousin breed carcasses.
显示更多 [+] 显示较少 [-]Quality and acceptability of value-added beef burger
2010
F. A. Khalafalla | Fatma H. M. Ali | A. H. Abdel-Azeem | Gehan M. A. Kassem | M. M. T. Emara
The sensory quality attributes of coated and uncoated beef burger patties formulated with texture soy granules or vegetables (peas and carrots) were studied in comparison to that of the control ones. Incorporation of textured soy granules significantly reduced the color, marbling, appearance, flavor, tenderness, juiciness, taste and overall acceptability in comparison with either control or vegetable extended burger. Addition of peas and carrots to uncoated burger significantly reduced the binding scores in raw samples, as well as flavor and juiciness in cooked samples, however, no significant differences could be observed in the other sensory attributes in both raw and cooked products. Vegetable extended burger had the highest cooking loss percent (20.14), followed by control samples (17.83), while soy extended product had the lowest value (15.82%). Application of batter and breading to vegetable extended burger significantly improved the investigated sensory parameters in comparison with the uncoated samples. On the other hand, application of batter and breading to soy extended burger revealed no improvement in the sensory quality attributes in both raw and cooked samples. Addition of soy granules and vegetables significantly increased the moisture, ash and carbohydrate and reduced the fat content of raw burger patties. Moreover the incorporation of textured soy significantly increased the protein content.
显示更多 [+] 显示较少 [-]Mycological investigations in beef and chicken luncheon
2005
Fatma H. M. Ali | Refaat M. Farghaly | Hammad A. M.
A total of 40 samples of beef and chicken luncheon (20 samples for each) were collected from different markets in Giza city. Samples were subjected to Mycological investigations. Beef luncheon were highly contaminated than chicken luncheon (3.1 x 103 /g ±0.3x 10³) and (4.0 x 102 /g ±0.2x 10² ) respectively . Seven mould genera were isolated from examined samples. The majority of which were Aspergillus (19.7% and 18.1%) and Penicillium (18.9% and 15.7 %), while, Mucor (7.1% and 4.7%), Cladosporium (4.7% and 3.9%) and other genera were also isolated from the same samples but in low percentages from beef and chicken luncheon respectively. The predominant identified Aspergillus species were; A. niger (18.7% and 14.5%), A. flavus (18.7% and 12.5%) and A. ochraceous (6.3% and 6.3%) in the two products respectively. The main identified Penicillium species were; P. citrinium (20.6% and 13.6%), P. expansum (11.4% and 13.6%) and P. verrucosum (6.8% and 6.8%) from the same products respectively. Examination for mycotoxin production revealed the detection of ochratoxin A at a higher level (mean 21.0 and 27.0 ng /kg) from 2 (10%) samples of beef luncheon and one (5%) sample of chicken luncheon, respectively. Aflatoxin B1 (mean 15.3 and 9.8 ng / kg) was detected in 4 (20%) samples of beef luncheon and 3 (15%) samples of chicken luncheon, respectively. Other mycotoxins (AFB2, AFG1, AFG2 and T-2) were detected but in minor levels. Public health significance of the identified mould species and the detected mycotoxins were discussed.
显示更多 [+] 显示较少 [-]Effect of gamma irradiation on beef quality
2005
H. M. Mohamed | M. M. T. Emara. | M. D. H. Farag | F. A. Elnawawi
Beef longissimus dorsi steaks were treated with 10, 25, and 50-kGy gamma irradiation and weekly examined during refrigeration storage at 5ºC to evaluate the changes in their organoleptic, bacteriological, chemical and nutritional quality characteristics as well as deterioration criteria. The signs of spoilage became apparent after 17 days of refrigeration storage in control untreated samples compared with 52 days for 10 kGy treated samples; however, samples treated with 25 or 50 kGy remained without signs of spoilage until the end of storage period (4 months). A characteristic burnt flavor was distinguished in irradiated beef samples, which was intensified with high irradiation dose, but decreased during storage. High doses of irradiation especially 50 kGy resulted in a brownish color of meat surface. Moreover, gamma irradiation resulted in high thiobarbituric acid values after treatments and during storage due to lipid oxidation. Thiamin content of beef was severely reduced and the reduction was dependant on the irradiation dose. Riboflavin was also affected by irradiation, but it was much stable than thiamin. The proximate chemical composition of beef was slightly affected by irradiation.
显示更多 [+] 显示较少 [-]Isoelectric focusing of proteins in the pH gradient as a tool for identification of species origin of raw meat
2018
Różycki, Mirosław | Chmurzyńska, Ewa | Bilska-Zając, Ewa | Karamon, Jacek | Cencek, Tomasz
Health, religious, and commercial aspects justify the need for meat species identification. The lack of officially approved methods prompts the undertaking of research on validation of isoelectric focusing of proteins (IEF) for official purposes. Samples were prepared from pigs (Sus scrofa ferus domestica), cattle (Bos taurus), and poultry (Gallus gallus domesticus). Meat mixtures were made by blending 50%, 25%, 10%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.2% meat of other species. Samples were examined on ultrathin polyacrylamide gels with pH 3–9 gradient. The results of the study confirmed the stable and reproducible pattern of meat protein bands. The detection limit of raw meat admixtures from pigs, cattle, and poultry mostly ranged from 2% down to 0.2% (0.2% for poultry). However, the IEF method can be used to detect the addition of pig meat to bovine meat in an amount higher than 3%. At the significant mixture level (i.e at least 5% addition of meat of another species) IEF proves itself with 100% specificity, sensitivity, and accuracy. The achieved detection limits provide a basis for recommending the IEF method for routine tests in laboratories detecting the species origin of meat.
显示更多 [+] 显示较少 [-]Effects of packaging methods on shelf life of ratite meats
2017
Horbańczuk, Olaf K. | Wierzbicka, Agnieszka
Over the last years a growing demand for ratite meat, including ostrich, emu, and rhea has been observed in the world. Ratite meat is recognised as a dietetic product because of low level of fat, high share of PUFA, favourable n6/n3 ratio, and higher amounts of iron content in comparison with beef and chicken meat. The abundance of bioactive compounds, e.g. PUFA, makes ratite meat highly susceptible to oxidation processes. Moreover, pH over 6 creates favourable environment for fast microbial growth during storage conditions affecting its shelf life. However, availability of information on ratite meat shelf life among consumers and industry is still limited. Thus, the aim of the present review is to provide current information about the effect of ratite meat packaging type, i.e. air packaging, vacuum packaging with skin pack, modified atmosphere packaging (MAP), on its shelf life quality during storage, including technological and nutritional properties.
显示更多 [+] 显示较少 [-]Technological and nutritional properties of ostrich, emu, and rhea meat quality
2016
Horbańczuk, Olaf K. | Wierzbicka, Agnieszka
In recent years a growing demand for ratite meat, including ostrich, emu, and rhea has been observed all over the world. However, consumers as well as the meat industry still have limited and scattered knowledge about this type of meat, especially in the case of emu and rhea. Thus, the aim of the present review is to provide information on technological and nutritional properties of ostrich, emu, and rhea meat, including carcass composition and yields, physicochemical characteristics, and nutritive value. Carcass yields and composition among ratites are comparable, with the exception of higher content of fat in emu. Ostrich, emu, and rhea meat is darker than beef and ratite meat acidification is closer to beef than to poultry. Ratite meat can be recognised as a dietetic product mainly because of its low level of fat, high content of polyunsaturated fatty acids (PUFA), favourable n6/n3 ratio, and high iron content in comparison with beef and chicken meat. Ratite meat is also rich in selenium, copper, vitamin B, and biologically active peptides such as creatine (emu) and anserine (ostrich), and has low content of sodium (ostrich). The abundance of bioactive compounds e.g. PUFA, makes ratite meat highly susceptible to oxidation and requires research concerning elaboration of innovative, intelligent packaging system for protection of nutritional and technological properties of this meat.
显示更多 [+] 显示较少 [-]Influence of post-mortem muscle glycogen content on the quality of beef during aging
2016
Onopiuk, Anna | Półtorak, Andrzej | Wierzbicka, Agnieszka
Introduction: Glycolic changes which occur post-mortem have an impact on the physical and sensory features of beef, which in turn determine the successive processes and influence such beef quality traits as colour, tenderness, and cooling loss. The aim of this study was evaluation of the post-mortem changes in bovine meat during aging, quantitative analysis of glycogen and lactic acid, as well as examination of their impact on technological and sensory quality of selected muscles from Holstein-Friesian × Limousin breed carcasses.Material and Methods: The study included three muscles of different metabolic qualities and sarcomere length: m. semitendinosus, m. longissimus dorsi, and m. psoas major, collected from nine bull carcasses aged 24 ±2 months.Results: Significant correlations were found between the volume of cooling loss on individual days of aging and the pH value of muscle tissue, lactic acid and glycogen content, as well as beef lightness. However, no significant dependency between the volume of glycogen and the intensity of red and yellow colours was detected.Conclusion: The colorimetric analysis of glycogen and lactic acid can be an effective tool in predicting the quality of beef.
显示更多 [+] 显示较少 [-]Beef tenderness improvement by dietary vitamin D3 supplementation in the last stage of fattening of cattle
2017
Półtorak, Andrzej | Moczkowska, Małgorzata | Wyrwisz, Jarosław | Wierzbicka, Agnieszka
Tenderness is the most important characteristic of meat, determining consumer approval. There are numerous methods of its improvement, although of diverse effectiveness. addition of vitamin D₃ to the feed for a short period before slaughter (7–10 days) is one of the natural ways to enhance the tenderness. Vitamin D₃ is responsible for Ca²⁺ mobilisation in serum and increase in activity of proteolytic enzymes belonging to calpains, which results in significant improvement of beef tenderness and reduction of ageing time. The use of vitamin D₃ is an application tool determining tenderness improvement of beef with substantial reduction in processing costs. Moreover, shorter post mortem ageing process will exceed the retail display time, which will consequently reduce losses due to unsold meat being returned from shops to the manufacturers. Based on the results of studies conducted over the last 15 years, this paper presents the possibility and the effects of the use of vitamin D₃ to improve beef tenderness.
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