Ranking and multicriteria decision making in optimization of raspberry convective drying processes

Abstract

Serbia is one of the leading producers and exporters of raspberry in the world, and considering the short shelf life of raspberry, the processing, storage, and transport are some of the main issues to be addressed. A comparative experiment was conducted in order to find the suitable process parameters for convective drying that may be considered as the alternatives to freeze‐drying, which is a widely used preservation method for raspberry even though it is a costly and energy‐consuming method. Twelve convective drying regimens were applied with a combination of three influencing factors: air temperature (60°C, 70°C, and 80°C), air rate (0.5 and 1.5 m·s−1), and stage of raspberry (fresh and frozen). The final product, a dried raspberry, was assessed for chemical, physical, and mechanical properties and rehydration capacity. Deep ranking analysis by power eigenvectors (DRAPE) and sum of ranking differences (SRD) were used to uncover the differences and similarities between the applied drying methods. SRD showed that convective drying of fresh raspberries proved to be more similar to freeze‐dried raspberries than convective drying of frozen ones. Fresh samples dried at 60 °C air temperature and 1.5 m·s−1 air flow proved to be the most similar to the reference freeze‐drying method. This convective regimen gives samples with the lowest color change, shrinkage, and shape deformation. With the mechanical and chemical properties of these samples being observed, statistical Duncan's test show that there is no significant difference (P < .05) in terms of hardness, shear force resistance, total phenolic, and total flavonoid preservation, compared with freeze‐dried samples. DRAPE gave similar results, but it added the variable importance in ranking as well, and total phenol reduction was defined as the most important variable. These results can help practitioners to develop cheaper and simpler drying methods that would replace the freeze‐drying but keep the same quality of the dried products.

Effect of Selected Drying Methods and Emerging Drying Intensification Technologies on the Quality of Dried Fruit: A Review

“…When it comes to comparing methods, models and products, the sum of ranking differences (SRD) method is one of the most widely applied in food science [101]. It has been successfully applied to compare horticultural products [102], sensory attributes affecting overall liking [103], energy drinks [104], the nutritional value of insect species [105] and raspberry drying [106], just to name a few.…”

Factor analysis, sparse PCA, and Sum of Ranking Differences-based improvements of the Promethee-GAIA multicriteria decision support technique

“…Recent examinations have clearly and unambiguously shown that the sum of ranking differences (SRD) yields a multicriteria optimisation. In references [60,61], SRD was used as an MCDM technique. Lourenc ¸o and Lebensztajn have illustrated in two practical examples that SRD provides a consensus of eight MCDM methods without using any subjective weights [62].…”

Physics-Based Digital Twin Identifies Trade-Offs Between Drying Time, Fruit Quality, and Energy Use for Solar Drying

“…On the other hand, over-drying should be avoided, particularly concerning the final product quality. An optimized drying time and temperature could help to retain micronutrients and bioactive compounds (Stamenković et al, 2020), which improves the quality of the diet.…”