Preliminary investigation of possible effects of mineral clay treatment applied to oils produced from olives: focus on moisture removal and compositional changes

In this preliminary study, two non-filtered virgin olive oils (one freshly produced VOO-N; one VOO-O stored for one year) were subjected to moisture removal with mineral clay (raw or activated) and analyses were performed to attest possible effects on the quality of the product. The results demonstrated that the treatment of oil with mineral clay at 36-38 degrees C had no negative effect on the basic quality parameters or on the volatile comound profile. On the other hand, a significant decrease in the water amount as well as in pigments was observed in the samples subjected to this kind of treatment, in particular with raw clay. Regarding the colour measurement, the lightness (L) as well as the consumers' acceptability exhibited a marked increase when oils were treated with raw clay.

Automated summary

The preliminary study showed that removing moisture from virgin olive oil with mineral clay did not negatively affect quality parameters or volatile compound profiles. Instead, it significantly reduced water content and pigments, resulting in increased brightness and consumer acceptability of the oil when treated with raw clay.