Comparison of Traditional and Industrial Sausages - Baranjski Kulen and Kulenova Seka Using Comprehensive Proteome, Peptidome and Metabolome Techniques

Research background. Baranjski kulen is one of the most popular fermented meat sausages originating from Croatia. It has protected geographical indication, and is traditionally produced in the Baranja region of Croatia. Kulenova seka is a fermented sausage very similar to Baranjski kulen, but it has a different caliber and consequently, a shorter time of production. In recent decades, due to the high demand and popularity of these products, industrially produced Baranjski kulen and Kulenova seka have become available on the market. This work aims to identify specific characteristics of traditional and industrial sausages, Baranjski kulen and Kulenova seka on proteome, peptidome and metabolome level which could potentially lead to better optimization of the industrial production process in order to obtain an equivalent to the traditional product. Experimental approach. Protein profiles of Baranjski kulen and Kulenova seka (traditional and industrial) were analysed using two-dimensional gel electrophoresis followed by differential display analysis and protein identification using mass spectrometry. Peptidomics profiling analysis was performed via liquid chromatography-tandem mass spectrometry. Furthermore, aroma profiles were investigated via headspace solid phase microextraction and gas chromatography-mass spectrometry. Results and conclusions. The major identified characteristics of each product were: industrial Baranjski kulen - specific degradation of MYH1 and TITIN, overabundance of stress-related proteins and increased phenylalanine degradation; traditional Baranjski kulen - decreased concentration of phenylalanine and overabundance of ALDOA and CAH3; industrial Kulenova seka - specific MYH4 and HBA degradation process; traditional Kulenova seka - overabundance of DPYD and MYL1, degradation of ALBU and MYG, decreased concentrations of almost all free amino acids and increased amounts of smoke derived volatile compounds. Novelty and scientific contribution. In this preliminary communication, the first insights into protein degradation processes and generation of peptides, free amino acids and aroma compounds of industrial and traditional Baranjski kulen and Kulenova seka are presented. Although further research is needed to draw general conclusions, the specific profile of proteins, peptides, amino acids, and volatile compounds represents the first step in the industrial production of sausages that meet the characteristics of traditional flavour.

Mycobiota and Mycotoxin Contamination of Traditional and Industrial Dry-Fermented Sausage Kulen

The aim of this study was to identify and compare surface mycobiota of traditional and industrial Croatian dry-fermented sausage Kulen, especially toxicogenic species, and to detect contamination with mycotoxins recognized as the most important for meat products. Identification of mould species was performed by sequence analysis of beta- tubulin and calmodulin gene, while the determination of mycotoxins aflatoxin B1 (AFB1), ochratoxin A (OTA), and cyclopiazonic acid (CPA) was carried out using the LC-MS/MS (liquid chromatography-tandem mass spectrometry) method. The results showed a significantly higher number of mould isolates and greater species (including of those mycotoxigenic) diversity in traditional Kulen samples in comparison with the industrial ones. P. commune, as a potential CPA-producer, was the most represented in traditional Kulen (19.0%), followed by P. solitum (16.6%), which was the most represented in industrial Kulen samples (23.8%). The results also showed that 69% of the traditional sausage samples were contaminated with either CPA or OTA in concentrations of up to 13.35 µg/kg and 6.95 µg/kg, respectively, while in the industrial samples only OTA was detected (in a single sample in the concentration of 0.42 µg/kg). Mycotoxin AFB1 and its producers were not detected in any of the analysed samples (<LOD).

Electricity Generation from Hospital Wastewater in Microbial Fuel Cell using Radiation Tolerant Bacteria

Hospital waste is a type of hazardous waste that contains a wide range of dangerous substances, including radioactive materials. Radiation-tolerant microbes have shown an interest in treating this liquid waste. Radiation-resistant microorganisms were chosen from irradiated fermented sausage in this investigation. The activity of enzymes such as protease, lipase, and laccase was studied. For hospital wastewater treatment, a single chamber microbial fuel cell (sMFC) with a radiation-tolerant bacterial consortium was deployed. The microbial structure analysis showed the selected consortium was similar to Acinetobacter sp. The COD was removed at a rate of 90.10±0.30%, and the power density (PD) was 168.91±3.89 mW/m2. This was the first study to use the radiation-resistant Acinetobacter sp. bacterial consortia to treat hospital waste and generate power simultaneously.

Chemical quality parameters (water, protein, fat, NaCl ash and nitrites) in fermented sausage with the addition of Yersinia enterocolitica

The connection between diet and health was known to the oldest civilizations. Meat processing has influenced the increase of meat consumption, protein utilization and its energy value. Fermented sausages which are prepared in a safe way are rich in animal proteins and are an important part of the diet. Meat and adipose tissue are the basic ingredients in the production of fermented sausages, along with spices and salts, and other additives depending on the specifics of the product. Ripening is a process that separates raw sausages from all other types of sausages, and the quality of raw materials and their treatment directly affects the quality of the finished product, because the process of fermented sausage production is dominated by biological and biochemical processes. Different types of foods can cause food-borne illnesses, one of which is zoonotic yersiniosis caused by Yersinia enterocolitica. Due to the importance of Yersinia in meat, the European Food Safety Authority (EFSA) recommended that in addition to controlling the presence of Salmonella, it is mandatory to examine pork carcasses for the presence of Y. enterocolitica.

Influence of polyphenols on sensory properties of fermented sausages

In the current research, the use of polyphenols in the production of fermented sausages as a natural preservative and their influence on the sensory characteristics of these products were investigated. Polyphenols could have antimicrobial and antioxidant roles in meat products, but also a range of positive biological effects on consumers. The results of the research showed that the addition of polyphenols did not significantly affect the sensory properties (colour, cross-section appearance, consistency, odour and flavour) of the three groups of sausages (control fermented sausage and two sausage variants, one with nitrite and one without nitrite), and that sausages were highly rated during most of the storage period. In addition, all tested sausages were evaluated as acceptable until the end of the entire storage period, i.e., throughout the 280-day period after sausage production.

Prevalence, serovar, and antimicrobial resistance of Salmonella isolated from meat and minced meat used for production smoked sausage

The objective of this study was to research the prevalence, serovars, and antimicrobial resistance profiles of Salmonella isolated from meat and minced meat used for the production of fermented sausage. A total of 116 samples were tested, and among them, 20 (17.2%) were positive. Salmonella was detected in 3 (10.3%) beef samples, 5 (19.2%) pork samples, and 6 (20.7%) poultry samples. In minced meat, the Salmonella prevalence was 18.8%. Salmonella enterica serovar Agama (5.2%) was the most commonly identified serovar, followed by S. Enteritidis (4.3%), S. Typhimurium (3.4%), S. Infantis (2.6%), and S. Lindenburg (1.7%). Most of the serovars identified in the present study are recognized as frequent causes of human salmonellosis. Thus, the presence of these serovars means foods with these meats are a likely source of human infections. We found the Salmonella isolates exhibited high rates of resistance to antimicrobials tetracycline, ampicillin, streptomycin, and ciprofloxacin. The highest level of resistance was to tetracycline (75%), followed by resistance to ampicillin (50%), streptomycin (30%), ciprofloxacin (20%), gentamicin (20%), and neomycin (10%). The high-level resistance observed for some of the serovars calls for concern. Salmonella with multidrug resistance in meat used to produce fermented sausages is considered a high additional risk for human health.

Controlling Food Poisoning Bacteria in Fermented Chicken Sausage Using Lactobacillus plantarum

Lactobacillus plantarum (L. plantarum) bacteria is generally recognized as safe and widely used in the food industry. The current study aimed to study the antimicrobial effects of L. plantarum against some food poisoning microorganisms, such as Staphylococcus aureus (S. aureus), Bacillus cereus (B. cereus), and Escherichia coli (E. coli) in oriental fermented chicken sausage for 18 days of storage at 4ᵒC. The L. plantarum has broad-spectrum antimicrobial effects that enhance the quality and safety of food products. L. plantarum reduced the count of S. aureus, B. cerus, and E. coli to 1.54, 4.26, and 3.03 Log10, respectively, after 18 days of refrigerated storage. Moreover, there were significant effects of L. plantarum on pH, thiobarbituric acid, total volatile basic nitrogen, and sensory attributes of fermented sausage samples during storage time. It was revealed that L. plantarum enhanced the physic-chemical, sensory attributes, and shelf life of fermented chicken sausage. Moreover, L. plantarum inhibited the inoculated food poisoning bacteria in fermented chicken sausage. In conclusion, it is recommended to use L. plantarum in fermented meat products as a starter and a bio-preservative to enhance the quality of the fermented chicken sausage.