1.1 本试验方法涵盖了确定两种产品样品之间是否存在可感知的感官差异的程序。 1.2 该测试方法适用于单个感官属性或多个感官属性是否存在差异。 1.3 当样品之间的差异性质未知时，本试验方法适用。它不确定差异的大小或方向。未确定导致差异的属性。 1.4 与三角测试相比，duo-trio测试在统计上效率较低，但更容易由评估人员执行。有关duo-trio测试与其他三个样本测试比较的详细信息，请参阅参考文献 ( 1- 4. ) . 2. 1.5 本试验方法仅适用于产品同质的情况。 如果同一产品的两个样本通常可以区分，那么另一种方法，例如描述性分析，可能更合适。 1.6 本试验方法仅适用于产品不会引起过度感觉疲劳、携带或适应的情况。 1.7 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 该测试方法对以下测试目标有效: 5.1.1 例如，当成分、加工、包装、搬运或储存发生变化时，确定是否会产生可感知差异或不会产生可感知差异；或 5.1.2 选择、培训和监督评估员。 5.2 测试方法本身不会改变duo-trio测试的目的是否是确定两种产品在视觉上是否不同。只有选定的值 p d 、α和β变化。如果测试的目的是确定两个产品之间是否存在可感知的差异，则为α选择的值通常小于为β选择的值。 如果目标是确定两种产品是否足够相似，可以互换使用，则为β选择的值通常小于为α选择的值和 p d 被选择来定义“足够相似” 5.3 测试方法可能会根据测试目标或评估员对产品的熟悉程度而改变。平衡参考技术（参见 9.1.1 )通常在两种产品都不比另一种更熟悉时使用。恒定参考技术（参见 9.1.2 )当一种产品是控制/当前产品或评估人员熟悉时，经常使用。

1.1 This test method covers a procedure for determining whether a perceptible sensory difference exists between samples of two products. 1.2 This test method applies whether a difference may exist in a single sensory attribute or in several. 1.3 This test method is applicable when the nature of the difference between the samples is unknown. It does not determine the size or the direction of the difference. The attribute(s) responsible for the difference are not identified. 1.4 Compared to the triangle test, the duo-trio test is statistically less efficient, but easier to perform by the assessors. For details on how the duo-trio test compares to other three-sample tests, see Refs ( 1- 4 ) . 2 1.5 This test method is applicable only if the products are homogeneous. If two samples of the same product can often be distinguished, then another method, for example, descriptive analysis, may be more appropriate. 1.6 This test method is applicable only when the products do not cause excessive sensory fatigue, carryover or adaptation. 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 The test method is effective for the following test objectives: 5.1.1 To determine whether a perceivable difference results or a perceivable difference does not result, for example, when a change is made in ingredients, processing, packaging, handling or storage; or 5.1.2 To select, train and monitor assessors. 5.2 The test method itself does not change whether the purpose of the duo-trio test is to determine that two products are perceivably different versus that the products are not perceivably different. Only the selected values of p d , α, and β change. If the objective of the test is to determine if there is a perceivable difference between two products, then the value selected for α is typically smaller than the value selected for β. If the objective is to determine if the two products are sufficiently similar to be used interchangeably, then the value selected for β is typically smaller than the value selected for α and the value of p d is selected to define “sufficiently similar.” 5.3 The test method may change based on the test objective or the assessors’ familiarity with the product. The balanced-reference technique (see 9.1.1 ) typically is used when neither product is more familiar than the other. The constant-reference technique (see 9.1.2 ) frequently is used when one product is a control/current product or is familiar to the assessors.