Optimization of production of blanched apple chips using sublimation drying

Abstract

The aim of the research is to investigate the efficiency of producing blanched apple chips utilizing an innovative technology, namely sublimation drying. Apples of the “Aport Almaty” variety were stored at a temperature of 4°C prior to processing. They were peeled, seeded, sliced into segments of specific thickness, and subjected to drying in a drying chamber at temperatures of 45, 50, and 60°C. Following drying, the samples were analyzed for antioxidant content, phenolics, minerals, and vitamins. For comparative analysis, methods such as sublimation drying, conventional drying, and low‐temperature drying were also employed. Atomic absorption spectroscopy and high‐performance liquid chromatography methods are employed for the analysis of the mineral and vitamin composition. Each group consists of 30 samples. Analysis of variance revealed statistically significant differences in antioxidants (F(3, 116) = 12.48, p < .001), water activity (F(3, 116) = 7.22, p < .01), and phenols (F(3, 116) = 9.85, p < .001) among the drying methods. Sublimation drying demonstrated higher levels of antioxidants and phenols (p < .05). At 45°C, sublimation drying resulted in higher levels of antioxidants (p < .05) and vitamin C, as well as low water activity (p < .05). Dry mass significantly correlated with storage stability (r = −0.75, p < .05). Sublimation drying exhibited superiority in moisture loss (F > 24.17, p < .001). The correlation coefficient between dry mass and moisture content was −0.82 (p < .01). Blanching improved antioxidant activity (75% vs. 65%) and color preservation.Practical applicationsOur study deepened the understanding of sublimation drying processes in apple chip production by determining optimal conditions for achieving high product quality. The obtained results provide valuable recommendations for practical application in the food industry, including optimal temperature regimes and the use of blanching to enhance chip quality. The universality of our study results supports their applicability in various sectors of the food industry that involve the drying of fruits and vegetables. Sublimation drying with blanching demonstrated high effectiveness in preserving the biochemical characteristics of the product, extending shelf life, and enhancing organoleptic properties.