What is ISO 4120 about?
ISO 4120 specifies a procedure for determining whether a perceptible sensory difference or similarity exists between samples of two products. The method is a forced-choice procedure. The method is applicable whether a difference exists in a single sensory attribute or in several attributes and only if the products are homogeneous.
The forced-choice method specified in ISO 4120 is statistically more efficient than the duo-trio test but has limited use with products that exhibit strong carryover and/or lingering flavours.
The method specified in ISO 4120 is effective for determining that either a perceptible difference result or a perceptible difference does not result. The method also determines selecting, training, and monitoring assessors.
Who is ISO 4120 for?
ISO 4120 on sensory analysis via triangle test is useful for:
- Food technologists
- Food manufacturers
- Food research and development agencies
- Quality testing department in the food and beverage industry
Why should you use ISO 4120?
A person's choices of food are influenced by factors such as price, preferences, previous experiences and what is healthy, but, more importantly, also by their senses. These include appearance, texture, taste, and smell. A sensory analysis of food products can provide manufacturers with insights that can be used in product development and marketing to cater to the right audience.
ISO 4120 specifies the forced-choice method that helps users to determine whether a perceptible sensory difference or similarity exists between samples of two products. It uses trial sizes and processes to generate sufficient superior quality data for statistical analyses.
Data from the triangle test can be analysed with the number of correct responses defined in ISO 4120. If the number of correct responses is greater than or equal to the number given in the tables (corresponding to the number of assessors and the α-risk level chosen for the test), conclude that a perceptible difference exists between the samples.
The method is effective for:
Determining that:
- Either a perceptible difference result (triangle testing for difference)
- Perceptible difference does not result (triangle testing for similarity) when, for example, a change is made in ingredients, processing, packaging, handling or storage
- Selecting, training and monitoring assessors
ISO 4120 benefits users by providing triangle test that is devoid of biases, errors and effects that can produce inaccurate results.
With ISO 4120, you will be able to determine the similarities and differences between samples of two products with the triangle test. As a result of this statistically more-efficient method you will be able to introduce newer and improved food products for your specified target audience. The accurate analysis of food can also help you enhance food quality, leading to better product development decisions in the food and beverage industry.
What is changed since the last update?
BS EN ISO 4120:2021 supersedes ISO 4120:2004. BS EN ISO 4120:2021 includes some technical changes with respect to ISO 4120:2004. These include:
- BS EN ISO 4120:2021 has been generalized beyond food and beverage applications
- Guidance on how to use the Thurstonian model in addition to the previously emphasized guessing model has been added