CHEMICAL COMPOSITION AND MICROBIAL SAFETY OF PORK MEAT PRODUCTS ORIGINATING FROM HERZEGOVINA

Th is paper presents the results of chemical composition and microbiological safety testing of dry cured meat products, fermented and semi-dry or pasteurized sausages produced by several meat industries from Herzegovina. In the period from 2016 to 2018, a total of 85 meat products were sampled. Th ese included 20 samples of fermented pork sausages, 10 samples of dry-cured pork loin, 5 samples of dry-cured pork neck and 50 samples of heat-treated sausages. Quality control testing of the samples included determination of meat protein, crude fat, moisture, sodium nitrite and polyphosphates content in sausages, using standard analytical methods. It was confi rmed that all analysed samples meet the requirements in terms of chemical composition, level of additives and microbiological safety. In comparison with dry cured meat products and sausages analyses results, with minimum requirements that are set forth in regulations for that product category. Th e above mentioned suggests that the analysed samples are good quality products and they are in compliance with the regulations.


INTRODUCTION
Food legislation lays down general principles and requirements for meat products and ensures that only safe products can be placed on the market.
According to current regulations, the quality of foodstuff s including meat products is determined according to their chemical composition and product specifi cation, i.e., specifi cation sheet. Production process and quality of food products is systematically addressed by relevant legislative and inspection authorities, but it is also in the spotlight of consumers. Increased health awareness and knowledge about food-related risks strongly aff ects current consumer demand trends. An accurate insurance of the safety of food products requires determination of product composition by application of appropriate chemical and microbiological analyses (Aćimović et al., 2014).
Dry cured meat products are common traditional foods, which have been produced and consumed worldwide over the centuries. Th ey contain a variety of fl avours and textures and are considered an important segment of local economy and an essential part of the cultural and gastronomic heritage. Technology of production of dry cured products, regardless of the type, involves salting, drying and ripening procedures (Krvavica et al., 2012). However, the quality of these products relies upon the selection of raw materials and processing technologies. Knowledge and understanding of highly complex chemical reactions in the tissues facilitate improved control of the processing system and the quality of fi nished products as well. Cured meat products are widely accepted and popular among consumers. However, the adverse eff ects of dry cured meat products and sausages such as high contents of salt, saturated fats and cholesterol, etc. must not be neglected (Popelka, 2016;Čop, 2016). Traditional manufacturing process might be associated with certain risks related to environmental conditions, hygiene, animal health, welfare on the farms, etc. (Oiki et al., 2016). Sausages are produced by stuffi ng selected ground mixture (meat, fat tissue, skin, off al, connective tissue and other ingredients) into natural or artifi cial casings (Kovačević, 2001). Dry fermented sausages are considered products of highest quality. In the region of Herzegovina, such sausages are commonly produced from pork meat, sometimes mixed with certain amount of beef, which undergo fermentation, smoking and drying process. Fermented dry sausages from Bosnia and Herzegovina are usually put on the market under commercial names "kulen", "zimska salama", "srijemska kobasica", "sudžuk" and "čajna kobasica" and a wide range of similar products is also available. According to the Regulation for minced meat, semi-fi nished meat products and meat products (Anonymous 2013 a,b,; Anonymous 2017) heattreated sausages are defi ned as meat products manufactured from the mixture of minced meat, mechanically deboned meat, fat and adipose tissue, off al, blood and blood products of diff erent mincing degree and additional nonmeat ingredients. A portion of fi lling for heat-treated sausages, i.e. meat batter or meat emulsion, is shaped into natural or artifi cial casing, pouch, mold, and subjected to heat treatment -pasteurization with/without smoking or boiling and sterilization. In Bosnia and Herzegovina, heat-treated sausages are marketed as fi nely minced or roughly minced boiled semi-durable sausages, whole-cut meat sausages or boiled and other heat-treated sausages.
As there is lack of relevant information on meat products manufactured in B&H, the aim of this research was to identify basic nutritional parameters and microbial safety of nine diff erent types of semi-dry and dry meat products manufactured in several meat factories from the region of western Herzegovina and sampled over a three-year period. An overview of the results of analyses of chemical composition and microbial safety of fi nished products from the group of fermented dry sausages, dry cured meat products and heattreated sausages (fi nely minced boiled, semi-dry, whole-cut meat sausages) is presented. For each sample, the contents of proteins, crude fat and water were determined and the microbial population were determined. Quantifi cation of sodium nitrite and polyphosphates was performed for all the samples from the category of dry fermented and heat-treated sausages. Th e obtained results were compared with the reference values laid down in the national regulations with the aim to evaluate the quality and microbial safety of meat products as well as to determinate the content of nitrites and polyphosphates (Anonymous 2013a,b,c, 2016, Anonymous 2017; Anonymous 2018a,b).

MATERIAL AND METHODS
Th is research was conducted on 85 samples of semi-dry and dry processed meat products manufactured by several meat companies. According to the classifi cation laid down by the Regulations (Anonymous 2013a and 2017), the samples were categorized into fi ve categories -20 samples of fermented dry sausages ("čajna kobasica" and "zimska salama"), 15 samples of dry cured meat products (dry-cured pork tenderloin and dry-cured pork collar -"budjola"), 10 samples of heat-treated sausages (fi nely minced cooked sausages -frankfurter), 20 samples of roughly minced cooked sausages ( "kranjska kobasica" and "narodna kobasica") and 20 samples of sausages made of whole cuts of meat ("kuhana šunka" and "pica šunka"). Th e sampling was performed randomly over a 3-year period (2016-2018) in the territory of western Herzegovina -municipalities of Široki Brijeg, Ljubuški, Grude, Čitluk and Posušje as well as in the city of Mostar.
Sampling and sample preparation were conducted according to the standard procedure (ISO 3100-1:1991). All analyses were performed in the labora-

Statistical data analyses
Th e results are presented as a mean value± standard deviation. Descriptive statistics (minimum, maximum, mean value, standard deviation, variance, modus and median) was calculated for all analysed variables. Th e data were processed using Microsoft Offi ce Excel 2016 (Microsoft , SAD) soft ware package.

RESULTS
In dry cured products, water content varied between 29.0% in dry pork collar and 52.1% in dry-cured pork tenderloin. Total fat content ranged from minimum value in pork tenderloin (15.5%) to a maximum of 45.0% in drycured pork collar. Th e highest average protein content (21.8%) was determined in a dry-cured pork collar "budjola" (Figures 1 and 2). In dry fermented sausages, the highest protein and fat contents were determined in "zimska slama", amounting29.7% and 43.4%, respectively. High water content (27.7%) was found in "čajna kobasica". Th e highest protein and fat contents in the group of semi-dry sausages were determined in sausages "narodna kobasica" and "kranjska kobasica" amounting 28.6% and 53.3%, respectively. Water content ranged between 24.3% in "kranjska kobasica" and 29.8% in "narodna kobasica". Th e average contents of proteins, fat and water in frankfurter sausage were 17.6%, 24.1% and 58.3%, respectively. Th e analyses of sausages made of whole cuts of meat revealed an average protein content of 13.2% in cooked ham and 14.7% in "pizza šunka", whereas lower fat content (9.0%) was determined in "pizza šunka" and higher moisture content (73.3%) was found in cooked ham.  Food additives are used in meat industry with the aim to improve sensory properties of food, enhance processing procedures or extend durability of the products, results are presented in Table 1. Th ese results revealed high variation of sodium nitrite concentration between dry sausages and heat-treated sausages comparing to low variation between polyphosphates content. 3.2 ± 0.7 Our research did not reveal the presence of food borne pathogens Salmonella spp., L. monocytogenes in any of the analysed samples. Th e indicators of process hygiene -total counts of aerobic mesophilic bacteria, Enterobacteriaceae, sulphitoreducing clostridia, E. coli and Staphylococcus aureus and other coagulase positive staphylococci were less than 10 colony forming units per 1g products, which is in compliance with the minimum requirements laid down in the Regulation.

DISCUSSION
Chemical composition of meat products from Herzegovina is similar to industrial products from neighbouring countries, where similar processing technologies are applied (Croatia, Slovenia and Serbia). Th e water, protein and fat content in dry cured products is typical and comparable with the results for similar types of products from Bosnia and Herzegovina (B&H) and Croatia industrial products in our research is higher than content in traditional homemade product from Croatia (15.4% and 19.5%, respectively) (Kozačinski et al., 2008). Pleadin et al., (2009;2017) reported somewhat lower contents of proteins (15.1%) and fat (24.6%) for semi-dry sausages from B&H, which could be attributed to diff erent recipes used by specifi c manufacturers (the amount of added bacon, the use of more or less lean meat). Th e results of this study for sausages made of whole cuts of meat correspond with previously reported results (Pleadin et al., 2009) for similar heat-treated sausages from Croatia.
All the analysed products were in accordance with requirements of the Regulation No. 82/13 (Anonymous 2013a) with regard to their chemical composition. Th e results of this research suggest that dry sausages are products of highest quality and commercial value due to their ingredients and nutritive value, i.e. the selection of best-quality meat and long ripening period. Compared to semi-dry and cooked sausages, dry products are characterized by lower moisture content.
Th is research revealed low concentration of sodium nitrite and polyphosphates. Kovačević  . According to this Regulation, a maximum permitted level for sodium nitrite (mg kg-1) in dry-fermented sausages is 50 mg kg-1, 100 mg kg-1 for heat-treated sausages, 50 mg kg-1 for dry-cured meat products and 100 mg kg-1 for semi-dry-cured meat products. Maximum permissible level for polyphosphates is 5 g kg-1 for all meat products.
From a public health perspective, fermented and heat-treated meat products can be analysed for their technological, biochemical, toxicological, nutritive and other properties. Complex production process and diverse health aspects of fermented meat products require a multidisciplinary approach enabling an insight into potential risks and control thereof (Zdolec, 2016). Meat and meat products are highly suitable medium for microbial growth. Th us, meat products can contain organisms that are responsible for desirable specifi c taste of fermented products (sensory properties), harmful agents that can cause undesired changes of the texture, colour or taste of fermented products as well as pathogens, which can harm the health of consumers. Some of the most important foodborne pathogens that can be found in fermented meat products and heat-treated sausages are Salmonella spp, L. monocytogenes, S. aureus and E. coli (De Cesare et al., 2007;Stojanac et al., 2015). Fermented meat products are a food vehicle in the outbreaks usually caused by Salmonella spp. or verocytotoxigenic E. coli (Paramithiotis and Drosinos, 2016). Fermented meat products with a pH ≤ 4.4 and water activity (aw) ≤ 0.92, or with pH ≤ 5.0 and aw ≤ 0.94 do not enhance the growth of pathogenic bacteria. However, although considered formally safe, the risk still exists and is associated with post-processing contamination -e.g. during slicing or packaging. Regarding the aforementioned, fermented meat products could still be considered potentially risky food. Th e results of microbiological analyses confi rmed the microbiological safety of pork meat products originating from Herzegovina.

CONCLUSION
According to the results obtained in this research and data from the literature, we can conclude that fermented dry sausages, dry cured meat products and heat-treated sausages have chemical composition similar to products from other parts of B&H, Croatia, Serbia and Slovenia. Th e analyses of the obtained results strongly indicate that all product samples are of good quality and in compliance with relevant legislation.