Sodium Sulfite Presence and its Influence on Physicochemical and Microbiological Characteristics of Refrigerated Ground Beef

Background: Ground meat stands among the most consumed meat products, being its safety easily damaged by increasing the surface area of contact after grinding it, what facilitates the growth of pathogenic and deteriorating micro-organisms. In order to decrease the lost because of deterioration, trade has been utilizing fraudulent devices as the addition of intentional preservative such as sodium sulfite. This research aimed to identify the presence of sodium sulfite in cooled ground beef commercialized in business establishments located in Porto Alegre city, state of Rio Grande do Sul, Brazil. In addition, it addressed the evaluation of the influence of using this addictive in cooled ground meat front its physic-chemical and microbiological characteristics and residual capacity in the first 48 hours. Materials, Methods & Results: A total of 55 samples of cooled ground beef, from non-noble cuts, acquired in business establishments located in Porto Alegre city, were collected. Thus, microbiological analyses for total and thermotolerant coliphorms, Clostridium Sulfite reducers, Staphylococcus coagulase-positive, Salmonella sp. and a qualitative test, for verifying the presence of sodium sulfite, were carried out. Subsequently, half of the negative samples (24) in the sulfite test were separated, and 0.04 g of this addictive for each 50 g of ground beef (0.08%) was, then, added. In these samples, microbiological and color analyses, and the confirmation of the presence of sodium sulfite, at times 0, 24 and 48, after the simulation of fraud of the samples, were realized. Moreover, for the verification of safety, microbiological analyses for Salmonella sp., Staphylococcus coagulase-positive, Clostridium Sulfite reducers, total and thermo tolerant coliphorms were carried out. Data were analyzedby Analysis of Variance (ANOVA), with pairwise comparisons done by the Tukey test, for a level of significance of 5% (P < 0.05). Thereby, from the total of 55 (100%) analyzed samples of cooled ground beef, two (3.63%) showed the presence of sodium sulfite addictive, and the performed microbiological analyses indicated the presence of Salmonella sp. in eight (14.54%) samples. The values of L*, observed in the samples added with sulfite, maintained constant at times (zero, 24 and 48) compared with the control samples (without addition of sulfite) (42.92; 40.35 and 41.69, vs 44.67; 37.65 and 32.38, respectively), which demonstrated lost of luminosity in the course of time. Also, the values of a* and b* demonstrated stable at times (zero, 24 and 48) in the samples added with addictive (5.72; 6.89; 5.47 and 9.73; 10.69; 9.56, respectively), although this has not occurred with the control samples that presented a gradual lost of these tonalities (11.48; 7.21; 5.91 and 16.11; 12.88; 7.84, respectively) (P < 0.05). Discussion: The results indicated that two (3.63%) samples showed the presence of sodium sulfite, being in disagreement with the Ordinance n. 1004 that forbids the addition of addictive a in natura meat. The presence of Salmonella sp. in samples of ground meat contradicts the Resolution RDC n. 12 that advocates its absence in 25 g of meat products. Furthermore, the conducted analyses of color proved that the addition of addictive in meat maintains its fresh color and appearance, beyond inhibiting reactions of enzymatic and non-enzymatic darkness during processing and storage. By considering the obtained results, it may be concluded that despite of a low incidence of fraud for finding sodium sulfite, this practice exists in business establishments located in Porto Alegre city, state of Rio Grande do Sul, Brazil, even though it can be concealed for the lack of continuous studies and legal analytical inspections, endangering sanitary-hygienic conditions of the products.