Sensory quality control in food companies: towards improving knowledge, attitudes and practices assessment as well as sensory quality management

Abstract

Limited knowledge and support for sensory quality control (SQC) in food companies and the associated misapplication of sensory evaluation principles may lead to defective products reaching consumers. Subsequently, customer dissatisfaction may lead to loss of sales and brand equity. It is therefore vital to assess the knowledge, attitudes and practices related to SQC in food companies to identify areas of improvement and deployment of targeted interventions. However, no tool could be found for evaluating SQC related knowledge and attitudes. Furthermore, despite the widely acknowledged link between waste and over-reliance on finished product monitoring for SQC, the practice of evaluating the sensory properties of finished products is still widely prevalent in the food industry. The focus on finished product may be due to the limited availability of research to develop a reliable system that manages sensory quality throughout the manufacturing process. Most studies focus on SQC of unit operations such as baking.

The first part of this study focused developing and validating of a questionnaire to assess SQC knowledge, attitudes and practices in the food industry. The questionnaire was developed based on sensory evaluation literature and was improved and validated through multiple phases and tests. These include content validation by sensory experts (n=6), tests to assess the clarity of questions by food company employees (n=8), item selection by item response analyses, factorial validity by exploratory factor analysis (EFA, n= 56 and 120) and confirmatory factor analysis (CFA, n= 225) and known groups validity. The knowledge questions retained in the final questionnaire had acceptable difficulty (-3 to +3) and discrimination (≥ 0.35) indices, while the attitude and practices questions had acceptable item-total correlation (≥ 0.20). Questions in the knowledge section formed one factor, which had a good model fit and good internal reliability. The attitudes questions formed two factors that accounted for negative and positive dispositions towards SQC. The model fit was however weak and will require improvement. The practices questions formed one factor with a good model fit and internal consistency. Overall, the results from the study demonstrate that the knowledge and practices sections of the questionnaire are valid measures for use in the food industry. The attitude section was not validated, hence it needs further refinement. However, the attitude section can still be used, and the results interpreted with caution. Food companies and other stakeholders can use the questionnaire developed in this study to rapidly assess the SQC related knowledge and attitudes of their employees and to audit company SQC practices towards unveiling areas of improvement of sensory quality systems. The second part of the study illustrates the development of a system (using a chocolate mousse case study) that prevents the occurrence of sensory defects across the manufacturing steps and thus ensures consumer satisfaction. First, the critical sensory quality indicators that drive consumer preferences were identified. These were used to define the product’s sensory specification and the severity of potential sensory defects. The severity and likelihood of occurrence of a sensory defect throughout the manufacturing process were used to identify the critical steps that must be controlled to prevent the occurrence of a sensory defect. Finally, a system for monitoring and control of the critical manufacturing steps was defined. The sensory quality system was developed based on established scientific principles of preference mapping and risk assessment. Thus, implementing the sensory quality system described is expected to prevent the occurrence of sensory defects and reduce the frequency of finished product testing by changing the goal from monitoring to validation. The focus on the sensory attributes that are critical to consumer preference would also ensure their satisfaction. Further research into the proposed system would be useful to validate its effectiveness. This study is the first to validate a questionnaire for assessing sensory quality control knowledge and practices in the food industry. It is also the first to demonstrate a system-based approach to sensory quality control, from the definition of sensory quality specification to control of the process from ingredient receipt to dispatch of the finished product.