Oils from kernels of various peach cultivars for the development of a craft technology

Abstract

The study provides a basis for a craft technology of producing oils from the kernels of stones of various peach cultivars harvested in the Odesa region and Moldova in 2020, 2021, and 2022. The most suitable cold pressing modes (extra virgin) have been chosen for kernels obtained from different cultivars. Crushed peach kernels should be wet-treated and

heat-treated at 40–50 °C for 15–20 min. During extraction by pressing, it is recommended that the crushed kernels (extraction mash) should not be heated above 50—60 °C for 5–7 min. The effectiveness of pressing has been established to be 33–47 % of oil. The thickness of an oilcake piece determines the effectiveness of pressing extraction. The thinner the oilcake piece, the more effective the pressing is: the load withstanding time, the compressive force, and the loading rate are significantly reduced, and the yield of oil increases. Thus, the most effective parameters of the pressing extraction stage for the kernels of all the peach cultivars are: residual oil content in the oilcake 5.0—6.0 %, oil yield 94.0 %, oilcake thickness 33.0 mm, load withstanding time 3.0 min, compressive force 10.0 kN, loading rate 5.0 kN/cm. The proposed technological mode of producing oils allows retaining the original fatty acid composition of the raw material to the maximum extent. After determining the

fatty acid composition of oils produced from the kernels of peach stones and their mixtures (harvested in 2020, 2021, and 2022), it was shown that the difference in ω-6 PUFA was 2.8 % and that in ω-9 MUFA was 1.9 %, depending on the cultivar.