© 2022, The Author(s), under exclusive licence to Springer Nature B.V.Apple pomace was used as a sole raw material for single cell oil (SCO) production by the oleaginous yeast Rhodosporidium toruloides DSM 4444. Preliminary studies with glucose medium revealed 100 mL of working volume in 500 mL Erlenmeyer flask as the most efficient in terms of lipid content. Thus, apple pomace hydrolysate was tested in six different conditions using 100 mL medium. The detoxified hydrolysate without chemical supplement (D medium) was found to be the most viable medium by 47.5 ± 2.47% lipid on dry cell basis (w/w). Apple pomace hydrolysate was also proven effective for SCO productions in bench-top fermenter (1 L working volume) under controlled temperature (25 °C), pH (5.0), and aeration (1vvm) by 40.1 ± 5.51% (w/w) lipid content. The same medium resulted in 50.9% (w/w) lipid on a dry cell basis in 30 L industrial-type bioreactor with 10 L of working volume, without exact control of temperature and pH. The results confirm that apple pomace is a prosperous raw material for SCO production in flask and fermenter scales. Graphical Abstract: [Figure not available: see fulltext.].