An interval valued Pythagorean fuzzy AHP integrated quality function deployment methodology for hazelnut production in Turkey

This study aims to investigate the effect of customer expectations and cultivation processes on the hazelnut industry in Turkey. Hazelnut is an essential fruit for meeting the energy needs of the body, and it grows in temperate climates, with Turkey being the largest producer in the world. However, changing climatic conditions, activities carried out unconsciously in the field of production, and the use of agricultural products and their content affect the quality of hazelnuts. To survive in this competitive environment, hazelnut producers in Turkey need to improve the cultivation process and meet customer expectations. In this context, the Pythagorean Fuzzy Analytic Hierarchy Process (PF-AHP) integrated Quality Function Deployment methodology is employed to analyze the cultivation process of hazelnuts grown in Turkey. Firstly, customer expectations are defined through literature review, experts' opinions, and customers' opinions on the Quality Function Deployment application. The expectations are then prioritized using PF-AHP. In order to meet the customer expectations, strategies to achieve required technical characteristics are designed based on interviews with producers. A relationship matrix is established to examine the impact of customer expectations on the product and production process, taking into account the technical characteristics. This process is examined using Quality Function Deployment. The results show that "Price stability due to state policies" is the most important customer expectation, and "Low costs" is a vital strategy to improve the quality of hazelnut production. Sensitivity analysis and comparative analysis are performed to evaluate the proposed method and test its accuracy. This study presents a practical and effective approach for farmers and companies to improve the quality of hazelnut production, and can be used as a reference for other agricultural products. The results of the study can provide directions to be developed in the cultivation process for hazelnuts grown in Turkey.