HISTOLOGICAL CHANGES IN VEINED RAPA WHELK MUSCLES (RAPANA VENOSA) AFTER FROZEN STORAGЕ

PURPOSE: The objective of this study was to establish the effect of freezing on the histological structure of veined rapa whelk (Rapana venosa). METHODS: Two hundred veined rapa whelks were collected from the Bulgarian Black Sea coast. Forty veined rapa whelks were subjected to histological analysis in the fresh state, while the remaining 160 veined rapa whelks were divided into 4 groups and frozen in a conventional freezer at -18ºС for 3, 6, 9 and 12 months, respectively. RESULTS: The histological assessment revealed irreversible damages in the entire structure. The observed changes were the smallest after 3 months and the greatest after 12 months of frozen storage. CONCLUSIONS: The histological finding can be used to distinguish fresh from frozen and thawed veined rapa whelks when making an official control

IN VITRO ANTIBACTERIAL ACTIVITY OF ROYAL GELLY AGAINST PATHOGEN ESCHERICHIA COLI

In the study was used a pathogen strain of E. coli, caused septicemia for ducks,resistant for different antibacterial agents: Amoxicillin, Lincospectin, Chloramphenicol,Doxycyclin, Enrofl oxacin, Sulfonamides and Trimetoprim. Bacterial suspension of E.coli icontaminated each from test solutions in TSB of royal jelly (n=6), mixes of royaljelly and rape honey, and independent used rape honey (10–45% v/v). Have in mindexactly counts of colonies before and after incubation from each of test substanceswas calculated the percent of reduction up to 30 min, and after incubation (24 hand 48 h). In almost all concentrations of royal jelly (10–45 v/v), were found totalinhibition effect to E. coli. Mixes from royal jelly and rape honey (1:100) possesseda higher antibacterial effect, compared with independent use of rape honey. Up to45% (v/v), rape honey does not cause total antibacterial reduction. Royal jelly andmixes from royal jelly and rape honey have potential as alternative therapeuticsagents against resistant for antibiotics pathogen strains of E. coli

An Authentication Survey on Retail Seafood Products Sold on the Bulgarian Market Underlines the Need for Upgrading the Traceability System

Economically motivated or accidental species substitutions lead to economic and potential health damage to consumers with a loss of confidence in the fishery supply chain. In the present study, a three-year survey on 199 retail seafood products sold on the Bulgarian market was addressed to assess: (1) product authenticity by molecular identification; (2) trade name compliance to the list of official trade names accepted in the territory; (3) adherence of the list in force to the market supply. DNA barcoding on mitochondrial and nuclear genes was applied for the identification of whitefish (WF), crustaceans (C) and mollusks (cephalopods-MC; gastropods-MG; bivalves-MB) except for Mytilus sp. products for which the analysis was conducted with a previously validated RFLP PCR protocol. Identification at the species level was obtained for 94.5% of the products. Failures in species allocation were reconducted due to low resolution and reliability or the absence of reference sequences. The study highlighted an overall mislabeling rate of 11%. WF showed the highest mislabeling rate (14%), followed by MB (12.5%), MC (10%) and C (7.9%). This evidence emphasized the use of DNA-based methods as tools for seafood authentication. The presence of non-compliant trade names and the ineffectiveness of the list to describe the market species varieties attested to the need to improve seafood labeling and traceability at the national level

Food safety knowledge and hygiene practices among veterinary medicine students at Trakia University, Bulgaria

The results from the first survey on food safety knowledge, attitudes and hygiene practices (KAP) among veterinary medicine students in Bulgaria are reported in this study. It was designed and conducted from September to December 2015 using structured questionnaires on food safety knowledge, attitudes and practices. Data were collected from 100 undergraduate veterinary medicine students from the Trakia University, Bulgaria. It was observed that the age and the gender did not affect food safety knowledge, attitudes and practices. There was no significant difference (p > 0.05) on food safety knowledge and practices among students based on the years of study. A high level of food safety knowledge was observed among the participants (85.06%), however, the practice of food safety was above average (65.28%) while attitude toward food safety was high (70%). Although there was a significant awareness of food safety knowledge among respondents, there is a need for improvement on food safety practices, interventions on food safety and foodborne diseases

Global Alliance for Chronic Disease researchers' statement on multimorbidity

Comment -No Abstract available

Meat Quality of Rainbow Trout (Oncorhynchus mykiss) and Brown Trout (Salmo trutta fario) Farmed in Bulgaria

Background: Fish meat is outlined with high nutritional value having essential amino acids, unsaturated fatty acids, mineral and vitamins. In this short report, we compared the meat quality of rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta fario) farmed in Bulgaria. Methods: Ten fishes from each species were purchased from a fish farm and their morphological parameters were determined. The technological properties of meat were analyzed such as water holding capacity and cooking loss as well as chemical composition such as water content, protein, fat, dry matter, and ash. Results were processed by STATISTICA 6.0 software. Results: Higher values were significantly determined in brown trout for standard body length (p0.05). Water holding capacity of rainbow trout meat (9.49±3.86%) was considerably better (p0.05). Conclusion: Meat of rainbow trout cultivated in Bulgarian farm exhibited better technological properties than that of cultivated brown trout; however, nutritional value of brown trout meat was superior. DOI: 10.18502/jfqhc.6.1.45

Some Physicochemical Characteristics of Fish Products Sampled from Bulgarian Retail Markets

Background: The quality and safety of fish products is determined by chemical, physical, and microbiological parameters, important for satisfying consumers’ requirements. Also, the freshness of fish is essential for evaluation of its quality. On the Bulgarian retail market, fish is commonly offered chilled, frozen, or processed. The purpose of this study was to determine some physicochemical characteristics of fish products sampled from Bulgarian retail markets. Methods: During June to July 2017, this survey was performed on 45 samples from smoked, semi-dried, marinated, and frozen fish products sold in Bulgarian markets. The samples were collected from specialized stores for fish products, and transported to the laboratory for analysis. Water content, water activity (aw), pH, salt content, and ash content were determined according to the standard protocols. Results: The highest average water content was established in frozen products, followed by almost equal values in marinated, smoked, and semi-dried fish products. The average aw value was also the highest in frozen products (0.975), it was almost the same in marinated and smoked (0.892); and the least in semi-dried fish products (0.905). Semi-dried (3.36%), marinated (3.19%), and smoked (3.03%) fish products had considerably higher average salt content than frozen ones (0.1%). The average pH value of marinated fish products (5.26) was lower than frozen (6.88), smoked (6.76), and also semi-dried (6.68) ones. Average ash content was substantially higher in smoked (7.16%), semi-dried (6.57%), and marinated (5.97%) fish products compared with frozen products (1.18%). Conclusion: It is concluded that the frozen fish products sold in Bulgarian markets are probably more susceptible to spoilage than marinated, smoked, and semi-dried ones. DOI: 10.29252/jfqhc.5.1.3

Histamine Level in Freshwater and Marine Fish Sold in Bulgarian Markets

Background: Histamine is an essential biogenic amine produced as a result of microbial decomposition of histidine during seafood processing and storage. The objective of this study was to evaluate histamine concentration in freshwater and marine fish marketed in Stara Zagora region, Bulgaria.&#x0D; Methods: Forty fish samples were purchased from local fish farms and retail stores in Stara Zagora, Bulgaria. Enzyme-Linked Immunosorbent Assay was used to determine histamine levels. The data were processed using GraphPad Software InStat 3.&#x0D; Results: Histamine was detected in 26 out of 40 (65%) samples, and none of them exceeded the regulatory limit of 200 mg/kg. The average histamine content in marine fish (6.965±3.187 mg/kg) was insignificantly (p&gt;0.05) higher than that in freshwater fish (4.503±1.133 mg/kg).&#x0D; Conclusion: The results reveal low levels of histamine in freshwater and marine fish indicating their good quality. However, its presence in seafoods remains a major food safety problem that requires permanent regulation of histamine concentration in fish.&#x0D;  </jats:p

Antimicrobial resistance of Aeromonas hydrophila isolated from different food sources: a mini-review

Aeromonas hydrophila is a Gram-negative, oxidase-positive, facultative, anaerobic, opportunistic aquatic pathogen. A. hydrophila produces virulence factors, such as hemolysins, aerolysins, adhesins, enterotoxins, phospholipase and lipase. In addition to isolation from aquatic sources, A. hydrophila has been isolated from meat and meat products, milk and dairy products, and vegetables. However, various studies showed that this opportunistic pathogen is resistant to commercial antibiotics. This is attributed to factors such as the indiscriminate use of antibiotics in aquaculture, plasmids or horizontal gene transfer. In this report, we highlight the occurrence, prevalence and antimicrobial resistance of A. hydrophila isolated from different food samples. The presence of antimicrobial-resistant A. hydrophila in food poses threats to public and aquatic animal health

Influence of Freezing on Muscles of Rainbow Trout (Oncorhynchus mykiss): A Histological and Microbiological Study

Background: Freezing is a common and ancient method for preservation of foods which is applicable both under household and industrial conditions. The objective of the study was to establish histological and microbiological changes in dorsal and abdominal muscles of rainbow trout (Oncorhynchus mykiss) after freezing once and twice.&#x0D; Methods: Forty-five fresh rainbow trout specimens were distributed into three groups of 15 fish each. The first group was subjected to histological and microbiological analysis immediately after delivery at the laboratory. The second fish group was frozen at -18 °C for 15 days, while the third group of fish was frozen at -18 °C for 15 days, thawed and frozen again at -18 °C for 15 days. Data were analyzed using GraphPad InStat 3 software.&#x0D; Results: After freezing once, muscle fibers with intracellular void spaces were observed and retained stable peripheral boundary. In some muscle fibers, the endomysium boundaries were visible and with retained integrity. After freezing twice, damages and deformities were observed resulting in completely destructured muscle fibers. Large void spaces among the muscle fibers and bundles were greatly the result of shrinking and grouping of fibers and the laceration of endomysium and perimysium internum. Total microbial count and Enterobacteriaceae count had no significant differences (p&gt;0.05) between fresh, frozen once, and frozen twice trout.&#x0D; Conclusion: Muscles of rainbow trout (O. mykiss) are histologically damaged to a greater extent after freezing twice and thawing. However, microbiological indicators had no change significantly after freezing once and twice.</jats:p