Mycoplasmas detection in milk samples ¿are the techniques reliable?

Food microbiology is an important aspect that must be considered during food manufacturing, which is, considering the possible sources of contamination, including operators. Highlighting that the group of mycoplasmas are little studied and therefore their presence in foods is not considered. Different mollicutes, particularly mycoplasmas, have been associated with economic losses in the poultry and dairy industries. The objective of this work was to determine the presence of the mycoplasma genus in milk samples through specific microbiological culture and to complement the diagnosis with the PCR technique. Two hundred milk samples were analyzed in Puebla city-Mexico. The samples obtained were centrifuge and reseeded in triplicate on SP4 agar, incubating and analyzed by stereoscopic microscopy. From each milk sample, DNA extraction was carried out with Zymo Research Quick-DNA™ Mini prep kit and primers AR1 and AR2 were used. The microbiological study showed positivity for mycoplasmas of 17% and 39%, in the liquid and solid phase, respectively. With the PCR technique, 53% positivity for mycoplasmas was obtained, which allows us to consider the presence of factors associated with samples of animal origin and that may be interfering with the sensitivity of the technique. Analyzing the viability of techniques to detect microorganisms, particularly mycoplasma, in foods is a practice that is recommended for the well-being of consumers.