MICROBIOLOGICAL EVALUATION OF POULTRY SAUSAGES STORED AT DIFFERENT TEMPERATURES

The aim of our study was to evaluate the microbiological quality of poultry sausages, which were stored at different temperatures (4 °C, 15 °C). Total bacterial count, coliform bacteria, yeasts and filamentous microscopic fungi were detected in poultry sausages. Microbiological quality was evaluated using the horizontal method for the determination number of microorganisms. Total bacterial count in sausages stored at 4 °C ranged from 1 × 10 1 CFU.g -1 in sample 1 (after opening) to 4.35 × 10 4 CFU.g -1 in sample 1 (7 th day of storage). Total bacterial count in sausages stored at 15 °C ranged from 3.25 × 10 3 CFU.g -1 in sample 1 (after opening) to 3.12 × 10 6 CFU.g -1 in sample 1 to 3.12 × 10 6 CFU.g -1 in sample 1 (7 th day of storage). Coliform bacteria in sausages stored at 4 °C ranged from 1 × 10 1 CFU.g -1 to 3.15 × 10 5 CFU.g -1 . Coliform bacteria in sausages stored at 15 °C ranged from 1.54 × 10 3 CFU.g -1 to 1.40 × 10 6 CFU.g -1 . Yeasts and microscopic filamentous fungi in sausages stored at 4 °C ranged from 2.75 × 10 4 CFU.g -1 to 1.40 × 10 6 CFU.g -1 . Yeasts and microscopic filamentous fungi in sausages stored at 15 °C ranged from 1.30 × 10 4 CFU.g -1 to 1.44 × 10 6 CFU.g -1 . Total bacterial count, coliform bacteria, yeast and microscopic fungi were not in accordance with Codex Alimentarius of Slovak Republic on 3 rd day in samples stored at


INTRODUCTION
Meat production is one of the major activities in Europe. The main type of meat produced is pork (48.7 %) followed by poultry (23.6 %) and bovine (23.3 %). Meat and meat products present an ideal substrate supporting the growth of several spoilage and pathogenic bacteria (Mataragas et al., 2006). Kozelová et al. (2011) investigated consumer's opinion about quality of meat and meat products of Slovak and foreign production on the Slovak markets. Quality of foreign products is highly appreciated by 15% of respondents; higher quality was highlighted by 36% of respondents, 30% of respondents highlighted the quality as lower, 19% of respondents labelled the quality of those products as very low.
In the last decade, chicken-based meat products have become increasingly popular worldwide due to their high nutritional quality and low cost and are available as either fresh or precooked (i.e. fried) chicken and/or microbiological products, which after subsequent packaging are usually stored under refrigeration (Barbut, 2002). Additionally, frozen chicken-based meat products also available on the market include specialties such as: nuggets, meatballs, hamburgers, frankfurters, etc.
Pathogenic non-spore-forming/spore-forming bacteria and viruses constitute a large proportion of all foodborne illness (EFSA, 2007). The presence of these microorganisms in raw pork and poultry is the result of their contamination from the live animal, equipment, employees and environment (Gianfranceschi et al., 2003, reduce or eliminate microbial contamination (Loretz et al., 2010).
The aim of this study was to evaluate the microbiological quality of poultry sausages on the first day of storage, after three days of storage, and after seven days of storage of the products at different temperatures (4 °C and 15 °C). In poultry sausages microbiological parameters: total bacterial count, coliform bacteria, yeasts and filamentous microscopic fungi were observed.

MATERIAL AND METHODOLOGY
Microbiological quality of poultry sausages was evaluated. These products are categorized of soft meat products.
Microbiological evaluation consisted of three parts: -determination of total bacterial count, -determination of coliform bacteria, -determination of yeasts and filamentous microscopic fungi.
There were evaluated 10 samples of poultry sausage, two analyzes were performed. Evaluation of poultry sausages were performed as follows: -two samples were evaluated immediately after opening (first day of storage), -two samples were evaluated after three days of storage at temperature 4 °C, -two samples were evaluated after three days of storage at temperature 15 °C, -two samples were evaluated after seven days of storage at temperature 4 °C, -two samples were evaluated after three days of storage at temperature 15 °C.

Characteristic of coliform bacteria
Coliforms are commonly used bacterial indicators of sanitary quality of water and foods. They are rod-shaped Gram-negative non-spore forming bacteria which ferment lactose into acid and gas at 35-37 °C. Coliforms are common inhabitants of the gut of the warm-blooded animals, but they can be found in the environment, on vegetation and in soil. Their presence indicates the potential presence of pathogenic organisms. Escherichia coli is a facultative mixed-acid fermenting member of the coliform group being capable of fermenting lactose at 44 °C. Presence of E. coli is considered as an almost sure sign of fecal contamination (Harwood et al., 2002).

Characteristic of total bacteria count
Detection of microbial contamination, particularly total bacterial count, sterility testing and selective determination of microorganisms, are common microbiological tests used on a large scale on food, environmental, medical and biological samples. Total bacterial count includes determination of mesophilic aerobic and facultative anaerobic microorganisms (Baylis, 2003).

Characteristic of microscopic fungi
Microscopic fungi include yeasts and microscopic filamentous fungi (moulds) are very important organisms. They are employed in the production of pharmaceuticals, enzymes, organic acids and food, and some of them are associated with several diseases affecting humans and other animals (Domingues et al., 2005).

Determination of total bacterial count, coliform bacteria, yeasts and filamentous microscopic fungi
The total bacterial count (TBC), coliform bacteria (CB), yeasts (Y) and microscopic filamentous fungi (MF) were determined. Plate diluting method was applied for quantitative CFU (Colony Forming Units) counts determination of respective groups of microorganisms in 1 g of meat products. Homogenized samples of meat components were prepared in advance by sequential diluting based on decimal dilution system application. Basic dilution (10 −1 ) was prepared as follows: 5 g of meat product was added to the bank containing 45 mL of distilled water. The cells were separated from substrate in shaking machine (30 minutes). Petri dishes of gelatinous nutritive substrate were inoculated with 1 mL of meat samples (TBC, CB, Y, MF) in three replications. For microorganism cultivation three types of cultivating mediums were used, to segregate individual microorganism groups. Plate count agar (E. coli) was used for CFU segregation of TBC (incubation 48-72 h at 30 °C, aerobic cultivation method). Dilutions of 10 -3 and 10 -4 were used to determine of TBC. Violet red bile agar (E. coli) was used for CFU segregation of CB (incubation 24 h at 37 °C, aerobic cultivation method). Dilutions of 10 -1 and 10 -2 were used to determine of CB. Chloramfenicol yeast glucose agar (E. coli) was used for CFU segregation of Y and MF (incubation 5-7 days at 25 °C, aerobic cultivation method). Dilutions of 10 -1 and 10 -2 were used to determine of Y and MF.
Al-Dughaym and Altabari (2010) found that the total bacterial count (TBC) in chicken nuggets were 2.7 × 10 4 and 3.0 × 10 6 CFU.g -1 . The Staphylococcus aureus counts were less than 10 2 CFU.g -1 and Escherichia coli was isolated from chicken nuggets in incidence of 60%, while Salmonella sp. was not detected. No. 1/2014 Coliform bacteria (CB) in sausages after opening of product was lower than 1 × 10 1 CFU.g -1 in sample 1 and 1.0 × 10 1 CFU.g -1 in sample 2. CB on 3 rd day of storage at 4 °C was lower than 1 × 10 1 CFU.g -1 in sample 1 and 2.20 × 10 2 CFU.g -1 in sample 2. CB in poultry sausages on 7 th day of storage at 4 °C was lower than 1 × 10 2 CFU.g -1 in sample 1 and 3.15 × 10 5 CFU.g -1 in sample 2 (Tab. 3). The number of coliform bacteria in meat products on 7 th day of storage at 4 °C were not in accordance with CA SR ( . Most common places of exposure were home and restaurants (malpractices/mishandling during food preparation). CB in poultry sausages on 3 rd day of storage at 15 °C was 1.95 × 10 3 CFU.g -1 in sample 1 and 1.54 × 10 3 in sample 2. CB in meat products on 7 th day of storage at 15 °C was 3.05 × 10 4 CFU.g -1 in sample 1 and 1.40 × 10 6 CFU.g -1 in sample 2 (Tab. 4). The number of coliform bacteria in meat products at 15 °C were not in accordance with CA SR (2006).
Enterobacteriaceae, a hygiene indicator (Zeitoun et al., 1994), were also part of the microbiota of ground chicken meat.
The population of Enterobacteriaceae (3.4 log CFU.g -1 ) is indicative of adequate hygiene conditions of production in the poultry plant.
According to Adams and Moss (1997) Enterobacteriaceae can grow under vacuum packaging and high-pH values in meat and produce high levels of H 2 S giving meat objectionable odours.
Pérez-Rodrígues et al. (2010) determined number of coliforms in cooked meat products from different establishments. Coliforms were found in 65% of analyzed samples, and counts were significantly lower than the other groups of microorganisms. The average value was 1.88 log CFU.g -1 , though it was obtained a maximum value of 4.90 log CFU.g -1 . E. coli was detected in 8 samples (<10 CFU.g -1 ).