ABSTRACT. Meat and meat products are highly perishable as they can provide an appropriate environment for microbial growth due to their high water activity and proper pH level. Quality, safety, sensory and nutritional properties of meat products are highly influenced by pathogenic and spoilage microorganisms. To prevent microbial growth, artificial antimicrobials have been used in food matrices, however safety concerns regarding the use of synthetic preservatives is a challenging issue. Additionally, consumer’s trend towards natural mildly processed products with extended shelf life necessitates the identification of alternative additives originating from natural sources of new acceptable and effective antimicrobials. Although the effectiveness of some natural antimicrobial agents has already been reported, still, there is lack of information regarding the possibility of using lysozyme as a preservative in meat and meat products either alone or in combination with other hurdles. In the present review the applications and beneficial effects of applying lysozyme in meat products, considering its limitations such as allergic problems, interactions with food constituents, reducing sensory changes and toxicity due to high required concentrations to prevent spoilage and oxidation in foods will be discussed.

This study was conducted to evaluate the antibacterial effect of Carum copticum essential oil (Ajowan EO) against Listeria monocytogenes in fish model system. Ajowan EO chemical composition was determined by gas chromatography/mass spectral analysis and the highest concentration of Carum copticum essential oil without any significant changes on sensory properties of kutum fish (Rutilus frisii kutum) was assigned. Then the inhibitory effect of Ajowan EO at different concentrations in presence of salt and smoke component was tested on L. monocytogenes growth in fish peptone broth (FPB), kutum broth and cold smoked kutum broth at 4 ºC for 12 days. Ajowan EO completely decreased the number of L. monocytogenes in FPB after 12 days of storage, however, antimicrobial effect of EO significantly reduced in kutum and cold smoked kutum broth. Addition of 4% NaCl and smoke component improved the anti-listerial activity of Ajowan EO in all fish model broths.

Um método simples confirmatório para determinação em HPLC-UV de resíduos de cetoconazol e clotrimazol em leite de vaca, após extração da fase sólida (SPE), é relatado neste artigo. Foram removidos das amostras proteínas e lipídeos por tratamento com acetonitrila e conseqüente extração em n-hexano. Os extratos foram posteriormente limpos e concentrados através de extração em fase sólida. Os analitos foram determinados quantitativamente usando um método validado de cromatografia líquida de alta eficiência. O método foi linear no intervalo de 0,1 a 1,0 µg mL-1 para ambos analitos. Os limites de detecção e quantificação para os analitos foram iguais a 0,01 e 0,1 µg mL-1, respectivamente. Parâmetros importantes que influenciam a eficiência da extração foram investigados e otimizados. O método proposto foi aplicado à análise de amostras de leite. Foram obtidas recuperações satisfatórias no intervalo de 95,9 a 101,78%, usando SPE.

A simple confirmatory method for HPLC-UV determination of ketoconazole and clotrimazole residues in cow's milk after solid phase extraction (SPE) is reported in this article. The samples were deprived of proteins and lipids by treating with acetonitrile and consequent extraction in n-hexane. Extracts were further cleaned-up and concentrated via solid phase extraction. The analytes were determined quantitatively using a validated high performance liquid chromatography method. The method was linear in the range of 0.1-1.0 µg mL-1 for both analytes. Limits of detection and quantification for both analytes were equal to 0.01 and 0.1 µg mL-1, respectively. Important parameters influencing the extraction efficiency were investigated and then optimized; the proposed method was applied to the analysis of milk samples. Satisfactory recoveries were obtained in the range of 95.9-101.78% using SPE.