Influence of homogenization cycle on the thermal and storage stability of kenaf seed oil (KSO) emulsion

The effects of homogenization cycles on the kenaf seed oil (KSO) emulsion stability was checked in this study. KSO nanoemulsions were prepared using a high-pressure homogenizer at 1, 3, and 5 cycles. Results showed that higher homogenization cycles provided the samples with a significant (p ≤ 0.05) smaller size of KSO droplets, but slightly disturbed the polydispersity index (PDI) and reduced (p ≤ 0.05) the zeta potential. All samples were within nano size (78.05—111.5 nm) and one high-pressure homogenization cycle treatment was chosen to proceed to the storage study. Over 28 days of storage at 4 and 30 °C, results showed that KSO nanoemulsion degradation was gradual in terms of increasing oxidation, droplet size, and PDI. There was no creaming and minimal flocculation until 21 days storage. The 30 °C storage maintained KSO emulsion at smaller droplet sizes, with minimal flocculation which was due to narrower PDI and higher zeta potential. Briefly, one cycle of high-pressure homogenization was sufficient to produce a stable KSO nanoemulsion, which was in small droplets, and physically stable during 28 days storage at 30 °C.