Caracterização dos parâmetros microbiológicos, físico- químicos e nutricionais da carne de caranguejo-uçá (Ucides cordatus) comercializada nas feiras livres e mercados da cidade de São Luís- MA

Abstract

This study aimed to determine the Most Probable Number (MPN) of total coliforms and coliforms at 45°C, quantify aerobic mesophilic bacteria, investigate coagulase-positive Staphylococcus, Salmonella spp., and Aeromonas spp. in crab meat, evaluate contamination of food handlers’ hands, apply questionnaires, develop an educational leaflet on hygienic-sanitary practices, and characterize the physicochemical properties (pH and cooking test), proximate composition (moisture, protein, lipids, ash, and carbohydrates), and caloric value of crab meat. A total of 110 samples of Ucides cordatus meat were analyzed, including 30 samples collected from three public markets and 80 samples from eight open-air markets in São Luís, Maranhão, Brazil. Microbiological and physicochemical analyses were performed according to conventional methods, and the data were analyzed by ANOVA at the 5% significance level followed by Tukey’s test.

Among market samples, 19 (63.33%) exceeded the acceptable limits for total coliforms and coliforms at 45°C. Aerobic mesophilic bacterial counts ranged from 1.3 × 10³ UFC/g to > 4.7 × 10⁴ UFC/g. Staphylococcus spp. were detected in 100% of the samples, with Staphylococcus aureus isolated from 10 samples. Aeromonas caviae and Aeromonas hydrophilla were detected in 23 and 3 samples, respectively. In open-air markets, coliform counts at 45°C ranged from 3 to 2400 MPN/g, with 38 (45.71%) samples exceeding regulatory standards. Aerobic mesophilic bacteria ranged from 9.6 × 10² to > 4.7 × 10⁴ UFC/g. Staphylococcus spp. were detected in 100% of the samples, with counts ranging from 5.1 × 10² to > 2.1 × 10⁵ UFC/g. Staphylococcus aureus was isolated from 45 meat samples (10 from public markets and 35 from open-air markets) and from the hands of 20 (100%) food handlers. A total of 59 isolates of Aeromonas caviae, 29 of Aeromonas hydrophilla, and one isolate of Aeromonas veronii biovar veronii were identified. Salmonella spp. were not detected in any sample. Questionnaire results demonstrated that crab meat extraction is an important source of income for the families involved in this activity, supporting the development of an educational leaflet on hygienic-sanitary practices. Physicochemical analyses showed pH values ranging from 6.6 to 8.0, and all samples met the standards for the cooking test (absence of ammonia and hydrogen sulfide odor, clear broth, and firm texture). Ash content ranged from 2.03% to 4.02%, lipids from 0.2% to 2.6%, proteins from 12.99% to 15.82%, carbohydrates from 0.4% to 1.4% in the first group and from 0.4% to 1.6% in the second group, moisture from 36.23% to 81.05%, and caloric value from 58.23 to 73.74 Kcal. The microbiological findings indicate that crab meat marketed in public and open-air markets in São Luís, Maranhão, is unsuitable for human consumption. However, the nutritional analyses demonstrate that Ucides cordatus meat is a valuable food source, characterized by high protein content, high juiciness, adequate moisture, and low lipid content.