**Karolina Brki´c Bubola \* , Marina Luki´c, Anja Novoseli´c, Marin Krapac and Igor Luki´c**

Institute of Agriculture and Tourism, Karla Huguesa 8, 52440 Poreˇc, Croatia; marina@iptpo.hr (M.L.); anovoselic@iptpo.hr (A.N.); marin@iptpo.hr (M.K.); igor@iptpo.hr (I.L.)

**\*** Correspondence: karolina@iptpo.hr; Tel.: +385-(0)52-408-341

Received: 11 September 2020; Accepted: 9 October 2020; Published: 12 October 2020

**Abstract:** With the aim to investigate the influence of post-harvest olive fruit storage temperatures on virgin olive oil production parameters, composition and quality, Istarska bjelica (IB) and Rosinjola (RO) fruits were stored for seven days at room temperature (RT), +4 ◦C and −20 ◦C prior to oil production. Lower temperatures delayed post-harvest maturation of IB fruits. Theoretical oil content did not change depending on the storage temperature, while the highest oil yield and extractability index were obtained after storage at RT. Chlorophylls decreased in IB-RT and in IB-20. A decrease in the sensory quality of oils was detected after fruit storage at RT and −20 ◦C, while the refrigeration temperature of +4 ◦C preserved it. Regarding the content of fatty acid ethyl esters, an increase was observed in IB-RT oils. Storage at RT increased the content of waxes, while the lower temperatures partially suppressed this phenomenon. In oils of both cultivars, storage at +4 ◦C preserved the concentration of most phenolic compounds at a level more similar to that of the fresh oil when compared to the other two treatments. In the production conditions, when prolonged fruit storage is necessary, refrigeration seems to be the most suitable option.

**Keywords:** olive fruits; storage temperature; virgin olive oil; FAEE; waxes; phenolic compounds; sensory analysis
