The detection of the antibacterial and odor-removing efficacy of dishwasher capsules should follow relevant standards and be comprehensively evaluated by combining multiple detection methods. The following is a specific analysis:
Antibacterial efficacy test
The basis of the testing standards: Mainly refer to standards such as QB/T 5133-2017 “Technical Requirements and Test Methods for Antibacterial and Bactericidal Functions of Household and Similar Dishwashers” and GB 21551.2-2010 “Special Requirements for Antibacterial Materials for Antibacterial, Bactericidal and Purification Functions of Household and Similar Electrical Appliances”. These standards specify the scope, definition, technical requirements, marking and test methods of antibacterial and bactericidal functions, providing norms and guidance for the detection of the antibacterial efficacy of dishwasher capsules.
The types of microorganisms to be detected: Escherichia coli, Staphylococcus aureus, etc. are usually selected as the detection strains. These strains of bacteria are common pathogenic bacteria, and the inhibitory effect on them can well reflect the antibacterial ability of dishwasher capsules.
Detection steps
Prepare the initial bacterial suspension with a concentration generally ranging from 5.0×10⁵ to 1.0×10⁶ CFU/mL or (5.0×10⁵ – 10.0) ×10⁵ CFU/mL.
Take 0.2mL of the bacterial suspension and add it respectively to the test samples (tableware treated with dishwasher capsules, etc.) and the control samples (tableware treated without dishwasher capsules, etc.).
The sterilized covering film was respectively applied to the experimental samples and the control samples, and they were cultured under the conditions of (37±1) ℃ and relative humidity >90% for (24±1) h.
Take out the culture samples, add 20mL of eluent respectively, wash off the test samples, control samples and the bacterial solution on the covering film, dilute them and count.
Evaluation indicators and determination: The calculation formula for the antibacterial rate R is R=
fracB−AB
times100
Among them, A represents the average number of recovered bacteria in the test sample, with the unit of CFU/ piece; B represents the average number of recovered bacteria in the control sample, with the unit of CFU per piece. When the antibacterial rate is ≥90.0% or ≥99.0%, it is evaluated as having antibacterial effect. The requirements for the antibacterial rate may vary slightly among different standards.
Odor removal effect test
The basis for the testing standards: Standards such as T/CAQI 87-2019 Cl.4.1.3 “Technical Requirements and Evaluation Methods for the Storage Function of Dishwashers” can be referred to. These standards put forward technical requirements and evaluation methods for the storage functions of dishwashers such as odor removal.
Detection method: Due to the complexity of odor components, current odor removal detection may involve multiple methods. For instance, the odor components in the air inside the dishwasher can be detected through professional detection equipment, and the concentration changes of the odor components before and after using the dishwasher capsules can be compared. Sensory evaluation methods can also be adopted, where professional evaluators score the degree of odor from the tableware or air inside the dishwasher.
Evaluation indicators: may include the removal rate of odor components, the degree of reduction in odor intensity, etc. For instance, by detecting the concentration of a specific odorous gas and calculating the reduction ratio of the gas concentration after using dishwasher capsules, the odor removal effect can be evaluated.
