Assessment of microbial quality and safety of ground beef/product sold in differrent retailers around Thohoyandou Area, Vhembe District, Limpopo

Abstract

Title: Assessment of microbial quality and safety of ground beef/product obtained from selected retailers around Thohoyandou area; Vhembe district; Limpopo. Background: It has been proven that animal products are easily contaminated with microorganisms, and this supports microbial growth if not properly handled, processed, and preserved. Ground beef and its wholesale products are becoming popular because of the demand for rapid meal preparation and services, especially in the fast-food industry. Despite the control measures in place, foodborne infections continue to be an immense problem, with millions of cases occurring annually worldwide. In South Africa, illnesses and deaths related to food consumption continue to be reported. In addition to the misery caused, the financial loss associated with meat spoilage and illnesses is enormous. Therefore, this study aimed to assess ground beef's microbial quality and safety in different retailers around Thohoyandou area, Vhembe District. Methodology: A total of 160 ground beef/product samples was randomly purchased from various retailers in Thohoyandou and transported on ice to the University of Venda microbiology laboratory for analysis. The potential microbes were cultured in enrichment media (peptone buffered water) for 5 minutes in room temperature. The culture was then sub-cultured in different plates containing selective media (e.g., EMB for E. coli, SS for salmonella and Shigella, MSA for Staphylococcus spp.) using the spread plate technique. Isolates were then identified by the Gram staining technique and biochemical tests such as Catalase, Urease, Citrate, Kligler Iron Agar, and VITEK system. Moreover, the antibiogram activity of isolated pathogens was screened against medically used and commercially available antibiotics. Furthermore, the DNA of the isolates was extracted, and multiplex PCR was conducted to determine different virulence genes and pathotypes. Hemolysin test was done in blood agar plates to identify virulence characteristics of E. coli isolates. Results: Out of 160 samples analyzed, E. coli was detected in 80 (50%), Staphylococcus spp. in 117 (73.12%), Salmonella in 60 (37.5%), and Shigella species in 108 (67.5%). Most Enterobacteriaceae (E. coli, Salmonella and Shigella) isolates were resistant to Ampicillin and Cefoxitin. Staphylococcus isolates showed high resistance to Cefoxitin (93.33%) and Oxacillin (93.33%). Out of 30 E. coli isolates subjected to mPCR assay, 23 isolates were of different pathotypes with EPEC (53.33%) being the most prevalent pathotype. Asta with 73.33% was the dominant virulence gene obtained. Thirty (30) E. coli isolates were tested for hemolysin activity and Alpha hemolytic activity was observed in 76.6% isolates, while beta hemolytic activity observed in 10% isolates. Some of the isolates presented non-hemolytic strains (13.3%). Conclusion: It was concluded that ground beef/products from established retailers were contaminated with pathogenic bacteria, and microbial quality was thus inadequate.