Effects of microcapsule constitution on the quality of microencapsulated walnut oil

Abstract

The encapsulation is a process by which small particles of core products are packaged within a wall material to form microcapsules. One of the most useful processes for drying thermosensitive substances that are unstable in aqueous solutions is the freeze-drying technique (lyophilization), which involves conversion of liquid oils in the form of an emulsion into dry powders. In this paper, the chemical composition of walnut oil and microencapsulation conditions (microcapsule wall material composition) have been evaluated in order to assess the influence of the microencapsulation process on the quality and shelf-life of microencapsulated walnut oil. Highest encapsulation yield was achieved when maltodextrin, carboxymethylcellulose, and lecithin were used as encapsulation agents and the ratio of oil-wall material was 1:1.5. Under these conditions all the oil was encapsulated. The presence of protein constituents in the microcapsule wall material extended the shelf-life of the microencapsulated walnut oil regardless of the use of antioxidant additives.

The Influence of Drying Process Conditions on the Physical Properties, Bioactive Compounds and Stability of Encapsulated Pumpkin Seed Oil

“…The observed changes in fatty acids generally agreed with previous findings reported in literature, e.g., the loss of unsaturated fatty acids normally increased with heating time and temperature (Choe and Min 2007), and unsaturated fatty acids are more susceptible to oxidation than the saturated fatty acids (Roszkowska et al 2015). Also, Calvo et al (2011) observed a similar dependency when analyzing encapsulated walnut oil, in which the content of linoleic acid was lower by 0.5-3.5% compared to the control sample. Results of our study also demonstrated that homogenization of the emulsion before spray-drying had no significant influence (p ˂ 0.05) on PUFA losses.…”

“…Generally, our study indicates that long-term aeration of the sample (72 h) during freeze-drying caused greater degradation of this group of compounds compared to shortterm high-temperature treatment. Opposite results were achieved by Calvo et al (2011Calvo et al ( , 2012, who encapsulated walnut and olive oils with the method of freeze-drying and found SFA saturated fatty acids, MUFA monounsaturated fatty acids, PUFA polyunsaturated fatty acids a Increase/decrease compared to the control sample that the content of tocopherols in the encapsulated samples differed insignificantly from that assayed in the samples of control oils. In general, high degradation of tocopherols in all analyzed powders could be explained by the presence of light and oxygen during the drying process (Anwar and Kunz 2011) since these compounds are not resistant to high temperatures (Bruscatto et al 2009).…”

“…This method can minimize product damage likely to occur as a consequence of high drying temperature used in spray-drying. Freeze-drying was used for the encapsulation of cardamom oil (Najafi et al 2011), flaxseed oil (Liu et al 2010;Karaca et al 2013), walnut oil (Calvo et al 2011), and fish oil (Anwar and Kunz 2011) and of functional ingredients like β-carotene (Spada et al 2012).…”

Single step extraction and derivatization of intramuscular lipids for fatty acid Ultra Fast GC analysis: application on pig thigh

“…The susceptibility was associated with the sample storage, while freeze-drying of samples is considered the safest drying process to preserve PUFA, because they are kept trapped within intact cellular matrices (Calvo et al 2011;Lee et al 2012). Moreover, the higher performance of the freeze-dried method for C 20:4 (n-6) does not confirm what reported by Ficarra et al (2013) about a better reliability of Folch method for PUFA determination.…”

Microencapsulation of Bioactive Food Ingredients and Controlled Release - A Review

“…Encapsulation technology has proven to be an excellent method to protect the sensitive food ingredients and to develop the novel foods formulations with improved properties [2][3]. Microencapsulation defined as a process of coat¬ing small particles of solids, liquids, or gaseous components, with protective coating material [4]. Microcapsules or micron size ranged from 2-5000μm.…”