The following tests are used to check the efficiency of pasteurization of milk except

• Methylene Blue Reduction Test' (MBRT): Is an indirect method for detection of microorganisms in milk – MBRT test is 'carried out on milk accepted for pasteurization' • 'Cold Pasteurization': The use of ionizing radiation or other means (e.g. chemical) to kill bacteria in food. • 'Electronic pasteurization': Food irradiation