An Adenosine Triphosphate Bioluminescence Method for Evaluating the Microbial Contamination of the Salad-Preparing Tables and Salad-Serving Dishes in Restaurants of Mashhad City, Iran

Introduction: Consumption of vegetable products is increasing commonly in the world because they are recognized as an important source of nutrients, vitamins, and fiber for humans. Salads are among the most widely used foods that are also known as the most contaminated foods in restaurants. This study was conducted to determine the microbial contamination of salad-preparing tables and salad-serving dishes. Materials and Methods: This study was conducted at 39 restaurants in Mashhad City in Iran during 2017. In this regard, 78 samples were determined from the salad preparing tables and serving dishes. Samples were tested for cleanliness status using Adenosine Triphosphate (ATP)-bioluminescence method as a rapid test.  Results: According to the ATP bioluminescence device, 43.6% of the assessed dishes were clean, 38.5 % were dirty, and 17.9 % were not adequately clean. According to the results of ATP bioluminescence device for tables, 23.1 % of the tested tables passed the test, 15.4 % were classified in the caution status, and 61.5% failed. Conclusion: The ATP method has been widely used, especially in the food industry, as a rapid method for measuring general levels of cleanliness. However, this method is not a reliable replacement for measuring the microbial contamination. The ATP bioluminescence should not be used as a substitute for quantitation of microbial load.