2.3.1: Descriptive Methods (Profiling)

Flavour profile advantages

Holistic Approach: Considers overall flavour perception.

Qualitative Insight: Provides qualitative descriptions of flavours.

Applicability: Suitable for various food and beverage products.

Flavour profile disadvantages

Subjectivity: Relies on subjective assessments.

Limited Detail: May lack specificity in describing individual flavour components.

Training Dependency: Results can be influenced by assessor training.

Texture profile

A texture profile is defined as the organoleptic analysis of the texture complex of a food in terms of its mechanical, geometrical, fat, and moisture characteristics, the degree of each present, and the order in which they appear from first bite through complete mastication.

Texture profile advantages

- Detailed Analysis: Provides a detailed assessment of texture attributes.

- Quantifiable: Allows for quantification of texture parameters.

- Reproducibility: Can be highly reproducible with well-trained assessors.

Texture profile disadvantages

- Resource-Intensive: Requires trained assessors and significant resources.

- Complexity: Assessing multiple texture attributes can be challenging.

- Limited to Texture: Primarily focuses on texture aspects, not flavour.

Quantitative descriptive analysis (QDA)

The results from QDA® are informative for statistical practices to meet project goal. Panel performance can be examined by interaction of product and panellist; product difference can be diagnosed by means of a one-way AOV based on attributes. Statistical procedures, such as multivariate analysis of variance, principle component analysis, factor analysis, cluster analysis can be widely applied to QDA® dataset1;means of attributes in the same sensory category can be graphically presented by a "spider web".

QDA advantages

- Quantitative Precision: Allows for precise quantification of sensory attributes.

- Structured Approach: Provides a systematic and structured evaluation process.

- Statistical Rigor: Allows for statistical analysis of sensory data.

QDA disadvantages

Time consuming: Requires substantial time for both training and analysis.

- Cost: Can be expensive due to the need for trained panels.

- Potential Bias:

Results may be influenced by panel training and composition.

Spectrum method

The Spectrum method is based on the use of precise, descriptive terminology (lexicons) that can be related back to product development at the bench.

Detailed physical and chemical descriptors of sensory attributes are used to discriminate among products and document each product's sensory profile.

spectrum method advantages

- Objective Measurements: Uses instrumental analysis for objective measurements. - Efficiency: Can be more efficient compared to purely sensory methods. - Automation: Allows for some degree of automation in data collection.

spectrum method disadvantages

- Limited to Specific Attributes: May not capture the full sensory profile. - Instrument Dependency: Results depend on the accuracy of instruments used. - Supplementary to Sensory: Typically used as a complement to sensory methods rather than a standalone approach.

key methodological features of QDA (descriptive technique)

Panel training: extensive training of a sensory panel

Attribute generation: collaborative generation of a comprehensive list of sensory attributes

Reference standards: establishment of reference standards for each attribute

Quantification: use of scales for quantitative scoring.

Replication: replication of evaluations for consistency.

Statistical analysis: application of statistical analyses e.g. ANOVA.

Advantages

- provides detailed quantitative info

- enables statistic analysis for identifying differences

- systematic and structured approach ensures consistency

Key methodological features associated with TEXTURE PROFILE ANALYSIS

Selection of texture attributes: identification of specific texture attributes

- Instrumentation: use of texture analysers for instrumental measurements

- Standardisation of procedures: adoption of standardised procedures for sample preparation and testing.

- Multiple evaluations: for assessing different texture attributes.

Mathematical analysis: application for parameter calculation.

Replication: of measurements for reliability.

Modified version of flavour profile

Some sensory scientists may develop variations of the traditional flavour profile method, incorporating additional attributes or refining the scoring system to better capture nuanced flavour characteristics specific to certain products or cultural preferences.

Modified texture profile analysis

Sensory scientists may customise the selection of texture attributes or adjust testing parameters to address specific product requirements. Variations in force settings or the inclusion of additional attributes may be incorporated.

modified Spectrum method

Instrumental techniques are customised. This includes measurement parameters, or analytical approaches based on the specific sensory attributes of interest. Modifications may be made to enhance efficiency or align with the unique requirements of the study.

why is product organisation important

Product organization is crucial in sensory evaluation for various reasons, and it plays a significant role in the preparation of the product, determining the amount needed for panel training and testing, and ensuring the availability of references where required.

Important of product preparation

Importance: Proper organization of products is essential for the systematic preparation of samples before they are presented to the sensory panel.

Explanation: Products need to be prepared in a consistent and controlled manner to ensure that each sample is presented to the panel under standardized conditions. This includes factors such as cooking methods, storage conditions, and presentation format. Well-organized product preparation contributes to the reliability and repeatability of sensory evaluations.

Amount of preparation for panel training and testing

Importance: Efficient product organization helps determine the quantity of product needed for both panel training and formal testing sessions.

Explanation: Understanding the amount of product required is crucial for planning and resource management. It ensures that an adequate supply is available for panel training sessions, allowing panellists to become familiar with the products. Additionally, it helps in estimating the quantity needed for the formal testing phase, avoiding shortages or wastage. Proper organization in this regard contributes to the smooth flow of sensory evaluations.

Product organisation: references when required

Importance: Some sensory evaluations may require the inclusion of reference samples for comparison or calibration purposes.

Explanation: Proper product organization includes the identification and preparation of reference samples that may be necessary for certain sensory tests. These references serve as benchmarks, aiding panellists in calibrating their sensory perceptions and providing a standard for comparison. Well-organized referencing ensures that the sensory panel has the necessary tools to make accurate and consistent evaluations.

Importance of Panel Performance in Descriptive Methods:

Data Quality: Trained panels are relied upon to provide accurate and consistent assessments of sensory attributes. Good panel performance ensures the quality of the data collected during descriptive analysis.

Consequence of Poor Performance: Inconsistent or inaccurate assessments can lead to unreliable data, impacting the validity of the results and the overall quality of the sensory analysis.

Product discrimination

Trained panels should be capable of discriminating subtle differences between products, contributing to the precision of descriptive methods.

Consequence of Poor Performance: If the panel lacks the ability to discriminate effectively, the method may fail to identify important sensory distinctions between products, limiting its utility in product development and

quality control.

Reproducibility: The reproducibility of sensory data is crucial for obtaining consistent results across multiple evaluations. A well-

performing panel ensures that assessments are repeatable over time.

Consequence of Poor Performance: Poor reproducibility may lead to inconsistent findings, making it challenging to draw meaningful conclusions about the sensory characteristics of products.

Attribute Intensity Scaling: Trained panellists need to use intensity scales consistently to quantify the intensity of sensory attributes. This ensures that results are expressed in a standardized and comparable manner.

Consequence of Poor Performance: Inconsistent scaling can lead to variations in attribute intensity scores, making it difficult to interpret and compare results accurately.

Consequences of poor panel performance

Unreliable Results: Poor panel performance can lead to unreliable and inconsistent results, undermining the credibility of the sensory analysis.

Ineffective Product Development: Inaccurate assessments may hinder the ability to identify and optimize sensory attributes during product development.

Resource Wastage: Poor performance may result in the waste of resources, including time and money invested in training and conducting sensory evaluations.

Incorrect Consumer Insights: If the panel fails to accurately represent consumer preferences, product modifications based on faulty sensory data may not align with actual consumer expectations.

Compromised Quality Control: In industries where sensory analysis is used for quality control, poor panel performance can lead to inadequate monitoring of product quality.

Recognise that the technique chosen will be dependent upon the number of products to be used, the test objectives and type of analysis.

The choice of sensory evaluation technique is highly dependent on several factors, including the number of products, the test objectives, and the type of analysis desired.

single sample tests (few products)

For a small number of products, single sample tests, such as the Duo-Trio test or the Triangle test, may be suitable.

These tests are designed to determine whether a perceptible difference exists between a reference sample and a test sample.

Descriptive Analysis:

If detailed information about specific sensory attributes is needed, even for a small number of products, descriptive analysis methods like QDA may be employed.

ranking tests

For a larger set of products, ranking tests, such as the Rank Sum test, can help establish the relative order of preference or intensity among samples. Sorting Tests: In cases where products need to be grouped based on sensory characteristics, sorting tests can be used

Test objectives

Discrimination Testing: Duo-Trio, Triangle, Discrimination tests: If the primary objective is to determine whether a perceptible difference exists between samples, discrimination tests are appropriate.

Preference Testing: Ranking Tests, Preference Mapping: If the goal is to understand preferences among products, ranking tests or preference mapping techniques may be chosen.

Descriptive Analysis: Quantitative Descriptive Analysis (QDA): When a detailed profile of sensory attributes is needed for each product.

types of analysis

Quantitative Analysis: QDA, Texture Profile Analysis (TPA): When precise, quantitative data on sensory attributes or textures is required.

Qualitative Analysis: Flavour Profile, Descriptive Analysis: If a more qualitative and detailed description of sensory attributes is the goal.

Nature of the Products: similar Products: Duo-Trio, Triangle tests: If the products are expected to be very similar, discrimination tests may be suitable.

Descriptive Analysis: For nuanced differences between similar products.

Diverse Products: Preference Mapping: When dealing with a diverse set of products, preference mapping can help identify patterns and preferences.

meaningful insights and practical application

Meaningful Insights: Profiling similar products provides meaningful insights into the sensory landscape of a specific product category. It helps in understanding the variation and preferences within that category.

Practical Application: From a practical standpoint, grouping similar products streamlines the sensory evaluation process. It allows for more efficient testing sessions and facilitates easier communication of results.

Name the main traditional descriptive methods

Flavour Profile

Texture Profile

Quantitative Descriptive Analysis (QDA)

SpectrumTM Method

Flavour profile

A method that considers overall flavour perception, providing qualitative descriptions of flavours.

Sweet

Savoury

Bitter

Sour

Umami

Recognise that many sensory scientists use a modified version of one of the above techniques.

It's common for sensory scientists to adapt and modify existing sensory evaluation techniques to better suit the specific needs and characteristics of their research or product development.

These modifications acknowledge the flexibility and versatility within the field of sensory science, where researchers often employ tailored versions of established methods to better meet the demands of their research objectives, or the characteristics of the products being evaluated. The adaptability of these techniques allows for a more nuanced and targeted approach in sensory analysis.

modified version of QDA

QDA protocols are often tailored to the unique characteristics of the products being investigated in the study. This may involve refining attribute lists, adjusting scales, or introducing novel evaluation criteria.

importance of panel performance for descriptive methods and mention the consequences of poor panel performance.

The performance of a sensory panel is of paramount importance in descriptive methods, where trained assessors play a critical role in evaluating and describing the sensory attributes of food products. The consequences of poor panel performance can have significant implications for the reliability and validity of sensory data.

Product harmony

A harmonious and collaborative panel is essential for reaching a consensus on attribute descriptions and scoring, contributing to the overall reliability of descriptive methods.

Consequence of Poor Performance: If there is disagreement or lack of consensus among panellists, the reliability of the method may be compromised, and the resulting data may be less robust.

Number of products

few products > single sample tests

Many products > ranking tests

Recognise that in general products profiled should be of a similar type or generic group, e.g. different brands/development samples of same flavour yoghurt.

Products used in a sensory test should be of a similar type or generic group for example different brands or development samples of same flavour yoghurt. When conducting sensory profiling, it's generally advisable to evaluate products that belong to a similar type or generic group. This ensures that the sensory analysis is focused and meaningful.

- consistency in evaluation

relevance of attributes

- effective discrimination

- meaningful insightful

- practical applications

consistency in evaluation

When products belong to a similar type or generic group, panellists can apply consistent criteria for evaluation. This consistency is crucial for generating reliable and comparable sensory data.

relevance of attributes

Products within the same type or group share common sensory characteristics. Profiling similar products allows panellists to focus on attributes that are relevant and meaningful for that specific product category.

effective discrimination

When comparing products within the same category, panellists are more likely to detect subtle differences or nuances in sensory attributes. This is particularly important for discrimination testing.