Scientific journal "Meat Technology"

Detection of celery and mustard food allergens in foods of animal origin in Serbia for the period 2021-2023

Vesna V. Janković — 2024-11-28

Food Allergy is a growing global public health concern. The presence of undeclared allergenic ingredients or the presence of traces of allergens due to contamination during food processing poses a great health risk to sensitised individuals. Celery and mustard belong to the group of 14 basic food allergens, and thus, they are potentially hazardous. Therefore, the objective of this mini-review is to evaluate the presence of celery and mustard in foods of animal origin in Serbia for the period 2021-2023. The present study provides a summary of qualitative detection of specific DNA sequences by real time PCR techniques conducted on 179 retail products of animal origin, i.e., coarse-ground cooked sausages, cooked sausages with meat pieces, fermented sausages, smoked products, chicken meat, dairy and meat alternatives, quick-frozen dough products and snacks. Celery DNA (the mannitol dehydrogenase gene region was used for specific celery identification in samples) was detected in 15 samples, while mustard DNA was detected in 14 samples.

Effect of vacuum packaging on microbial and sensory quality indicators of cold-smoked freshwater fish

Milan Milijašević — 2024-11-28

The aim of this research was to monitor the effect of vacuum packaging on selected microbial and sensory parameters of cold-smoked common carp (Cyprinus carpio) and cold-smoked bighead carp (Hypophthalmichthys nobilis) fillets stored at 3±0.5 ℃, and to determine the shelf-life of the products. Fillets were analysed on days 1, 7, 10,12, 14, 15 and 16. The APCs were significantly higher (p < 0.05) in common carp than in bighead carp from storage day 12. At the end of study, the APC in both species of fish had not reached 7 logcfu/g. No significant differences (p ˃ 0.05) were determined between the PBCs in common carp and bighead carp during the whole period of storage. In cold-smoked bighead carp, the lactobacilli group was dominant at the end of the storage period. According to sensory assessment, it was concluded that vacuum-packaged cold-smoked common carp remained acceptable for up to 15 days of storage, while vacuum-packaged cold-smoked bighead carp remained unchanged until the end of the study (16 days).

Effect of pomegranate (Punica granatum) fruit molasses as a natural marinade on the microbiological quality and shelf life of refrigerated chicken fillet

Hanaa S. Bekeir — 2024-11-28

Pomegranate molasses (PM) could be suitable as a marination ingredient in Mediterranean cuisine. This study is, thus, aimed at investigating the effects of PM on the microbial characteristics of chicken breast fillets. For this purpose, PM marinades were prepared at three different concentrations for the marination of chicken breast fillets, which were assigned to three treatment groups: T1 (immersed in 0.5 % v/w PM), T2 (immersed in 1.0 % v/w PM) and T3 (immersed in 1.5 % v/w PM). Chicken breast fillets were marinated for 2 hours and then aerobically stored at 4°C for 15 days. Non-marinated fillets were used as the control. Levels of aerobic bacteria, psychrotrophic bacteria, coliforms, and lactic acid bacteria were determined to evaluate the evolution of spoilage. The results revealed that the growth rate of the microbial populations during storage at 4°C decreased with the increasing concentration of PM. The groups of aerobic, psychrotropic, and lactic acid bacteria may be continuously increased on each sampling day, with bacteria numbers on the control and T1 fillets surpassing those on fillets exposed to the other treatments (p < 0.05) from day 3 until day 15, when sampling stopped. All PM treatments had significantly decreased coliform counts (p < 0.05) than did the control group. At 4°C, the shelf life of PM-marinated chicken breast fillets was significantly extended compared to the controls, achieving up to 6, 9, and 12 days for T1, T2, and T3, respectively, as evaluated by microbiological analyses. The findings of this study suggest that pomegranate molasses could be used as an ingredient to improve the microbiocidal quality of marinade or as a sole marinade, both of which uses could prolong the shelf life of chicken breast fillets.

In vitro evaluation of Hydrilla verticillata extract as a natural preservative for chicken meat

Pandi Prabha Srinivasana — 2024-12-02

The intent of this research is to study the preservative effect of ethanolic extract of Hydrilla verticillata enriched with chitosan coating on the meat sample to increase the shelf life of the palatable product. The chemical, microbiological, sensory, and nutritional analysis such as pH, the amount of lipid peroxidation, total bacterial count, protein, and fat content of the fresh chicken meat coated with ethanolic extract of H. verticillata and chitosan were performed for 21 days. The results of the experiment show that H. verticillata extract enriched with chitosan coating met the need to act as a preservative by degrading the growth of microorganisms, maintaining the pH, and also by increasing the nutritional values.

Biofilm production and acetic acid sensitivity of Staphylococcus aureus and Escherichia coli isolated from poultry slaughterhouse environment, broiler carcasses and offal in Algeria

Saïd Derbal — 2024-12-02

The environment of poultry slaughterhouses, broiler carcasses and offal can act as reservoirs and spread various zoonotic bacterial pathogens such as Staphylococcus aureus and Escherichia coli. The objectives of this study were to determine the prevalence of S. aureus and E. coli in broiler carcasses and offal, and the environment of poultry slaughterhouses, and to evaluate the capacity for biofilm formation and sensitivity to acetic acid of certain bacterial isolates. A total of 210 samples were taken from different parts of the carcasses (wings, thighs and breasts) and offal (livers and hearts) of broiler chickens, and 19 environmental samples were collected from various compartments of poultry slaughterhouses (walls, floors and equipment) to determine the prevalence of S. aureus and E. coli. Fourteen S. aureus strains and 14 E. coli strains isolated from broiler products, as well as 14 S. aureus strains and 14 E. coli strains isolated from the environment of poultry slaughterhouses, were specifically selected to evaluate their ability to form biofilms. The tube and the tissue culture plate methods were used to evaluate biofilm forming capacity, while the minimum inhibitory concentration (MIC) of acetic acid on these bacterial isolates was determined by the agar dilution method. The total quantities of biofilm produced by the different categories of bacterial strains were compared by statistical analysis. The prevalences of S. aureus and E. coli were 100% in broiler carcass and offal samples, while in environmental samples, the prevalence of E. coli was 94.73% and that of S. aureus was 78.94%. Using the tube method, 35.71% of S. aureus strains demonstrated strong biofilm production, 50% demonstrated moderate production and 14.28% demonstrated weak production. No strain was categorized as non-biofilm producing. Similarly, for E. coli strains, 32.14% had strong biofilm production, 21.42% moderate production, and 46.42% weak production, with no strain being non-biofilm producing. Using the tissue culture plate method, 39.28% of S. aureus strains had moderate biofilm production, while 60.71% showed weak production. No isolates were identified as having strong production or being non-biofilm producers. For E. coli strains, 14.28% showed strong biofilm production, 39.28% moderate production, and 46.42% weak production, with no isolate being categorized as a non-biofilm producer. The two methods made it possible to detect biofilm production by all studied bacterial isolates. The tube method revealed a higher rate of isolates with strong biofilm production (33.92%) compared to the tissue culture plate method (7.14%). In contrast, the tube method recorded a lower rate of isolates exhibiting moderate biofilm production (35.71%) compared to the tissue culture plate method (39.28%). Similarly, the tube method showed a lower rate of isolates with weak biofilm production (30.35%) compared to the tissue culture plate method (53.57%). Regarding measures of total biofilm produced, environmental bacteria presented a not significantly higher value (total optical density (OD)=12.45) than did bacteria isolated from broilers (total OD=11.83). Likewise, the total quantity of biofilm produced by all 14 E. coli (total OD=12.78) was numerically but not significantly higher than that produced by all S. aureus isolates (total OD=11.5). Among the isolates from broilers, the 14 E. coli strains produced a numerically not significantly higher amount of biofilm (total OD=6.76) than the 14 S. aureus strains (total OD=5.07). The minimum inhibitory concentration (MIC) of acetic acid was ≤0.08% for all bacterial isolates, except for two S. aureus isolates, for which the minimum inhibitory concentration was 0.16%. In conclusion, S. aureus and E. coli are frequently present in the environment of poultry slaughterhouses and in broiler products. All bacterial isolates demonstrated an ability to form biofilms. These bacteria were very sensitive to acetic acid, which is therefore considered an ideal agent for disinfection of the poultry slaughterhouses environment and decontamination of broiler carcasses.

Evaluation of food additive analyses based on five years of food safety and quality controls

Radivoj Petronijević — 2024-12-02

Analyses of eight groups of additives in food and animal feed for nearly five years were included in this research. Food samples were grouped according to EU directive 1333/2008 and national regulation 53/2018 into 18 food categories. A total of 4539 samples was analysed, of which the most numerous categories were meat and dairy products, with 2833 (62.4%) and 649 (14.3%) samples, respectively, and a total of 8203 analyses. Over 90% of all analyses were determinations of food colourants, inorganic anions and preservatives & sweeteners, accounting for 3478 (42.4%), 2937 (35.8%) and 1122 (13.7%) of the analyses, respectively. The least common were tartaric and fumaric acid determinations, and the food categories with the lowest numbers of analyses were: food supplements (rarest), fats and oils and fat and oil emulsions (second rarest), and sugars, syrups, honey and table-top sweeteners (third rarest). The analyses of additives are unevenly represented in food and animal feed and it is necessary to balance and harmonise them with legislative requirements. Adequate control of food additives is an important part of the regulatory requirements and can only be fulfilled by continuous monitoring of additive use in food and animal feed.

Assessment of carcass contamination in a slaughterhouse in the governorate of Blida, Algeria

Djamila Baazize Ammi — 2024-12-02

The initial contamination of meat occurs during slaughter procedures. The objective of this study was to evaluate the hygiene in a slaughter establishment by evaluating the surface contamination of the carcasses and the level of hygiene of the workforce, the environment and the equipment. Altogether, 122 samples were taken, (50 from carcasses and 72 from personnel, equipment and environment). The state of cleanliness of animals was assessed for 125 sheep and 150 cattle. Bacteriological analyses conducted were the enumeration of total coliforms, thermo-tolerant coliforms and Escherichia coli and the detection of Salmonella.

The carcasses were significantly contaminated with bacterial hygiene indicators and there were no significant differences (P> 0.05) in contamination levels between the carcass species, or between the days of the weeks or the microbial groups enumerated. Evaluation of animals’ cleanliness showed that 68% of the examined sheep were dirty or very dirty, and 91.33% of the cattle were lightly soiled or dirty. Examination of the contamination of personnel, equipment and the environment between the start and the end of the week did not reveal a significant difference (P> 0.05). In order to minimize the contamination of carcasses at the slaughterhouse level, it is recommended to apply good hygiene practices.

On-farm welfare conditions of dairy donkeys: A case study in Northern Serbia

Marija Kovandžić — 2024-12-04

The use of donkey milk in human nutrition and the cosmetic industry has led to increased interest in donkey breeding and, consequentially, the intensification of dairy donkey farms, particularly in Europe. Despite the expanding number of farms and greater milk production, there is still no consensus on the management and welfare conditions of donkeys. Therefore, this study aimed to assess and compare the welfare, health and housing conditions of dairy donkeys on five farms in Northern Serbia. The welfare of dairy donkeys on the five farms (A, B, C, D and E) was assessed using the Animal Welfare Indicator (AWIN) protocol for donkeys, represented by four principles (Good Feeding, Good Housing, Good Health and Appropriate Behaviour). Body condition scores were the highest on farms C and D. In addition, none of the examined dairy donkeys on farm D showed any signs of the examined health indicators (except for nasal discharge and hoof neglect) or inappropriate behaviour. Furthermore, the lowest percentage of nasal discharge and hoof neglect was recorded in dairy donkeys on farm D. In contrast, the highest frequency of alopecia, skin lesions, unhealthy hair coat, faecal soiling and hoof neglect was recorded in dairy donkeys on farm A. In conclusion, welfare conditions on farm A were rated as the most unacceptable, while the welfare conditions on farm D were rated as the most acceptable.