Steam-exploded camellia (Camellia oleifera Abel.) seed protein improves the stability of camellia seed oil emulsions

Summary We aimed here to investigate the ability of steam-exploded camellia seed protein (SECSP) in stabilising steam-exploded camellia seed oil-in-water emulsion in comparison with soy protein isolate (SPI). Emulsions with different SECSP and SPI contents (0.5, 1, 1.5 and 2 g 100 mL −1 ) were formulated and the effect of protein concentration on emulsion droplet size, zeta (ζ)-potential, physical stability and bioaccessibility was examined. The stability of emulsion increased with increasing protein concentration. SECSP emulsion was characterised by smaller droplet sizes, higher surface charge and better stability than SPI emulsion. Furthermore, SECSP emulsion exhibited good digestive stability. SECSP emulsion showed creaming only at protein concentrations above 0.5 g 100 mL −1 after 28 days of storage, while SPI emulsion showed stratification and flocculation during the same storage period. Hence, steam explosion pretreatment physical modification of camellia seed protein (CSP) provides a novel approach of utilising proteins for emulsions stabilisation, and digestive stability improvement under gastrointestinal conditions.