The effect of Storage on Physicochemical and Sensoric Properties 
of Cold-pressed Oils 
 Agnieszka Kita, Damian Janusz, Magda Aniołowska
Wrocław University of Environmental and Life Sciences, 
Department of Food Storage and Technology, Wrocław, Poland

The aim of the study was to determine the effect of storage time and temperature on physicochemical and sensoric properties of cold-pressed oils of cumin seeds, milk thistle and almonds. The material used for investigation were cold-pressed oils from black cumin seeds (Nigella sativa L.), milk thistle seeds (Silybum marianum L.) and almonds (Prunus dulcis L.).  The oils packed in dark glass were stored for 12 months under standard (20oC) and cooling (4oC) conditions. In fresh and after every two months of storage, the samples were analysed for acid, peroxide and anisidine values, fatty acid composition, conjungated dienes and trienes content, colour by spectroscopic method as well as for organoleptic properties. 
It has been stated that storage influenced properties of oils in different ways depended on raw material. Hydrolytic and oxidative changes were most intensive in the black cumin oil, while the best stability exhibited almond oil. The lowest TOTOX value after 12 months of storage was detected in the samples of almond and milk thistle oils and the highest in cumin oil. The highest losses of C 18:2 fatty acid were observed in cumin oil, while the lowest in milk thistle oil. The content of conjungated dienes and trienes increased only in cumin oil during storage. The stable colour during storage exhibited black cumin and almond oils, while the bigger changes were observed in milk thistle oil. Storage deteriorated the organoleptic properties of all oils. The most stable flavour during storage exhibited cumin oil, while  the least – almond oil. Decreasing storage temperature reduced adverse effects in all oils. 

Publication supported by Wroclaw Centre of Biotechnology, programme The Leading National Research Centre (KNOW) for years 2014-2018