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Blends of milk fat and canola oil (MF:CNO) were enzymatically interesterified (EIE) by Rhizopus oryzae lipase immobilized on polysiloxane-polyvinyl alcohol (SiO2-PVA) composite, in a solvent-free system. A central composite design (CCD) was used to optimize the reaction, considering the effects of different mass fractions of binary blends of MF:CNO (50:50, 65:35 and 80:20) and temperatures (45, 55 and 65 °C) on the composition and texture properties of the interesterified products, taking the interesterification degree (ID) and consistency (at 10 °C) as response variables. For the ID variable both mass fraction of milk fat in the blend and temperature were found to be significant, while for the consistency only mass fraction of milk fat was significant. Empiric models for ID and consistency were obtained that allowed establishing the best interesterification conditions: blend with 65 % of milk fat and 35 % of canola oil, and temperature of 45 °C. Under these conditions, the ID was 19.77 % and the consistency at 10 °C was 56 290 Pa. The potential of this eco-friendly process demonstrated that a product could be obtained with the desirable milk fat flavour and better spreadability under refrigerated conditions., Mješavina mliječne masti i kanola ulja (MF:CNO) enzimski je interesterificirana pomoću lipaze iz Rhizopus oryzae, imobilizirane na kompozitu od polisiloksana i polivinil-alkohola, u sustavu bez otapala. Da bi se reakcija optimirala, upotrijebljen je centralno složeni dizajn (CCD), pri čemu su ispitani utjecaj masenog omjera MF:CNO (50:50, 65:35 i 80:20) i temperature (45, 55 i 65 °C) na sastav i teksturu interesterificiranih produkata, uz zavisne varijable: stupanj interesterifikacije i konzistenciju pri 10 °C. Na stupanj interesterifikacije bitno su utjecali maseni udio mliječne masti u mješavini i temperatura, dok je na konzistenciju utjecao samo maseni udio mliječne masti. Dobiven je empirijski model pomoću kojeg su utvrđeni optimalni uvjeti interesterifikacije: mješavina 65 % mliječne masti i 35 % kanola ulja, te temperatura od 45 °C. Pri tim je uvjetima postignut stupanj interesterifikacije od 19,77 %, a konzistencija pri 10 °C bila je 56 290 Pa. Pomoću ovog ekološkog postupka može se dobiti proizvod poželjnog mliječnog okusa i bolje mazivosti pri hladnim uvjetima skladištenja.