RESUMO
AIM: Determination of the effect of microorganisms on spoilage of meat products during various temperature regimes of storage by integral indexes of luminescent lines in their spectra and development of an algorithm of microorganism indication by an express method using laser Raman-luminescent spectroscopy. MATERIALS AND METHODS: Minced meat from beef and pork was used. Determination of quantity of mesophilic aerobic and opportunistic-anaerobic microorganisms was carried out by serial 10-fold dilutions with subsequent parallel seeding into Rida count total 24 plates and Petri dishes with 5% blood agar. Sample study was carried out in luminescent software-hardware complex Enspectr L405 (a variant of Enspectr M software-hardware complexes). RESULTS: Meat spoilage was established to be caused to a large degree by Pseudomonas genus (P. fluorescens, P. putida, P. fragi et al.) bacterial growth. Raman-luminescent spectra of bacteria that compose microflora, characterizing and accompanying beef and pork spoilage, were measured and recorded into a database. CONCLUSION: The results obtained will allow to use this technique in the future for both express-indication and differentiation of microorganisms and express-evaluation of quality of meat products at all stages of their manufacturing, storage, transport and realization.
Assuntos
Microbiologia de Alimentos , Pseudomonas/isolamento & purificação , Carne Vermelha/microbiologia , Animais , Bovinos , Humanos , Lasers , Medições Luminescentes , Pseudomonas/patogenicidade , Análise Espectral Raman , Suínos , TemperaturaRESUMO
AIM: Development and evaluation of express diagnostics of microorganisms for reduction of time spent on study execution. MATERIALS AND METHODS: Giant Raman scattering effect and proposed substrate with metallic nano-balls of silver were used for identification and indication of microorganisms. Staphylococcus aureus, Staphylococcus haemolyticus, Staphylococcus saprophyticus, Candida albicans, Escherichia coli, Bacillus subtillis, Pseudomonas aeruginosa were used as objects of study. All the microorganisms were cultivated in dense nutrient media and non-fluorescent microbiological membrane filters. RESULTS: Giant Raman scattering method on the substrates used increases sensitivity of indication and specificity of identification of microbes compared with other existing express methods and allows to see the signal from a single bacterium when exposed to laser light. The methodic proposed was also used to determine sensitivity of bacteria to antimicrobial preparations. CONCLUSION: The proposed hardware and method may be used for express diagnostics of processes of microbial nature.