Mycopopulations and ochratoxin A: Potential contaminants of Petrovská klobása

Petrovsk? klob?sa is traditionally produced dry fermented sausage from the area of Backi Petrovac (Vojvodina Province, Serbia) that has been protected with designation of origin (PDO) according to Serbian legislation. Contamination of this kind of sausage casings by different mould species often occur during the production process, mainly during the ripening and storage. The aim of this study was to isolate and identify moulds that contaminate ingredients used for Petrovsk? klob?sa production and its casings during different phases of ripening and storage. Sampling was done during the production process and after 2, 6, 9, 11, 14, 34, 65, 90, 120, 217 and 270 days. Total mould counts in components ranged from 1.60 (mechanically mixed filling) to 4.14 (red hot paprika powder) log10 CFU/g, while the number of moulds isolated from sausage casing surfaces ranged from 0.01 (C3 sausage, 217th day) to 1.60 (C1 sausage, 270th day) log10 CFU/cm2. After total mould counts were determined, isolates were identified and classified in five genera for components (Penicillium - 7 species; Fusarium - 2 species; Aspergillus - 1 species; Alternaria - 1 species; Verticilium - 1 species) and 3 genera for casings surfaces (Penicllium - 3 species; Aspergillus - 1 species; Eurotium - 1 species). It was appointed that 83.33% of isolated species are potential producers of toxic metabolites. The analyses of ingredients and sausages on the presence of ochratoxin A, following the ELISA method, gave the negative results.

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Non-thermal inactivation of Listeria spp. in a typical dry-fermented sausage: “Bergamasco” salami

Italian Journal of Food Safety ◽

10.4081/ijfs.2019.8112 ◽

2019 ◽

Vol 8 (3) ◽

Cited By ~ 1

Author(s):

Erica Tirloni ◽

Vanessa Di Pietro ◽

Giuseppe Rizzi ◽

Francesco Pomilio ◽

Patrizia Cattaneo ◽

...

Keyword(s):

Lactic Acid ◽

Listeria Monocytogenes ◽

Lactic Acid Bacteria ◽

Production Process ◽

Water Activity ◽

Growth Potential ◽

Worst Case ◽

Fermented Sausage ◽

Dry Fermented Sausage ◽

Control Samples

Aim of the present study was the evaluation of the growth potential of Listeria spp. inoculated in the typical North Italian dry fermented sausage “Bergamasco” salami during its production. As it was necessary to carry out the challenge test in the production line of the industry, according to the guidelines of the European Reference Laboratory for Listeria monocytogenes, a non-pathogenic “surrogate” microorganism was used: for the inoculum, two strains of Listeria innocua (1 ATCC, 1 strain isolated from a similar substrate) were used. The inoculation of the samples occurred during grinding and mixing of the sausage mass, before the filling. To avoid cross-contamination, the control samples were produced before the contaminated ones. After the dripping, salamis were subjected to the normal production process (drying and maturation in five steps at specific temperatures and humidity rates). The inoculated products were subjected to the enumeration of Listeria spp. at T0 (day of inoculation) and at T4 (post-drying), and every 10 days during curing (T10, T20, T30, T40, T50, T60, T70, T80 and T90), as this salami is generally sold as whole piece with varying levels of curing (from T20 to T90). Since the product may be cut in half and vacuumpacked, at each of the times starting from T20, half salami was vacuum-packed and stored for 30 days at 12°C, at the end of the which Listeria spp. enumeration was performed again. At all times and for each type of samples of each of the three batches, the enumeration of the natural microflora (Total Viable Count, lactic acid bacteria, Pseudomonas spp., Enterobacteriaceae) and the determination of water activity and pH were performed on control samples. The product was characterized by a high concentration of microflora (8-8.5 Log UFC/g), consisting mainly of lactic acid bacteria, added to the mixture at the beginning of the production process. The pH showed a decrease over time, expected for this type of products, due to the development of lactic acid bacteria (final pH: 5.42-5.55). The water activity reached values able to inhibit the development of Listeria spp. (final aw: 0.826-0.863). Listeria counts in the tested batches of “Bergamasco” salami showed the absence of significant growth in the product with a reduction of loads if compared to T0, between -0.59 and -1.04 Log CFU/g. Even in the samples subjected to vacuum packaging and storage at 12°C, the absence of significant increase of lactic acid bacteria in the product was highlighted with further decrease of bacterial loads (-0.70/-0.79 Log CFU/g if compared to T20). Considering the worst case scenario (thus the batch with the highest growth potential), in the products stored in the curing room at 14-16°C, at humidity of 80% and in the samples stored at 12°C and vacuum packaged, the threshold indicated by the EURL Lm guidelines (+0.5 Log CFU/g) for the growth of Listeria spp. was not reached, allowing to classify “Bergamasco” salami in the category 1.3 of the EC Reg. 2073/2005 as “Ready-to-eat food unable to support the growth of Listeria monocytogenes”.

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Effects of Temperature, Humidity and Additives on the Formation of Biogenic Amines in Sucuk during Ripening and Storage Periods

Food Science and Technology International ◽

10.1177/1082013204041992 ◽

2004 ◽

Vol 10 (1) ◽

pp. 21-28 ◽

Cited By ~ 25

Author(s):

H. Bozkurt ◽

O. Erkmen

Keyword(s):

Biogenic Amines ◽

Histamine Concentration ◽

Fermented Sausage ◽

Dry Fermented Sausage ◽

Effects Of Temperature ◽

And Storage

The effects of temperature (20, 30 and 40 C), humidity (50, 65 and 80% RH) and additives on the formation of biogenic amines (tryptamine, -phenyl ethylamine, putrescine, cadaverine, histamine, 1,7-diamino heptane, serotonin, tyramine, spermidine and spermine) in sucuk (Turkish dry-fermented sausage) were studied during ripening and storage periods. Cadaverine was not detected in any sausage. Tryptamine, -phenyl ethylamine, 1,7-diamino heptane, serotonin, spermidine and spermine were the minor biogenic amines found in sucuk. The formation of tryptamine, -phenyl ethylamine, histamine, 1,7-diamino heptane and spermidine were affected significantly (P<0.05) by temperature and% RH during the storage. Preservatives had also a significant effect (P<0.05) on the formation of biogenic amines. The lowest putrescine formation was observed in sucuk type containing the highest amount of additives after 60 days of storage, whereas the highest putrescine formation was obtained in the control sucuk made without additives. Histamine concentration ranged from 0.0 to 242.2 mg/kg and 0.0 to 135.8 mg/kg during ripening and storage periods, respectively. In general, tryptamine formation increased during ripening and decreased during the storage periods. Temperature and% RH of the storage might be used as hurdle factors to control the formation of biogenic amines in sucuk.

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