Impact of Sweet Orange Peel Essential Oil on the Nutrient and Oxidative Stability of Aquafeed During the Storage Condition

Abstract

The main goal of this study was to assess the qualitative composition of essential oil (P), a natural extract produced from wasted orange peels in the citrus processing sector. Additionally, the study aimed to investigate the alterations in fish feeds when this essential oil is incorporated and stored. The essential oil was extracted from the orange peels provided for the study using the hydrodistillation method and the Clevenger apparatus. The study determined the volatile components of the oil with 100% accuracy. The primary constituent was identified as D-limonene, comprising 59.27% of the total composition. Subsequently, experimental feed groups were established by including the essential oil in the feed rations at ratios of ‰0 (P0), ‰0.5 (P5), ‰1 (P10), and ‰3 (P30). Under storage conditions, the feeds were stored in feed sacks for 60 days. Periodic samples were collected during storage and subjected to nutritional, microbiological, structural, and oxidation tests. The results of the study show that P had no protective effect in fish diets against the growth of yeasts, molds, and other mesophilic aerobic bacteria (p > 0.05). It was shown that the nutritional values varied over time during storage. However, this variation was not substantially correlated with the amount of P in the diets (p > 0.05). There was no discernible impact of the addition of P on the structural characteristics of the feed grains. Nevertheless, the inclusion of P substantially impeded the process of lipid oxidation in the diet (p<0.05). After the two-month storage period, it was shown that adding at least 1 ‰ of P to the fish meals prevented the peroxide generated from oxidation in the feed from exceeding acceptable levels.

Keywords

• sweet orange peel essential oil
• aquafeed
• oil oxidation
• antioxidant
• shelf life
• industrial waste