Fabrication and Physicochemical Characterization of Pseudosciaena crocea Roe Protein‐Stabilized Emulsions as a Nutrient Delivery System

Abstract

The aim of this study was to develop a protein emulsifier that can be used to construct a nutrient delivery system. Pseudosciaena crocea roe protein isolate (PRPI) was prepared and tested for its emulsifying properties. Benzyl isothiocyanate (BITC) was used as a model delivery nutrient in the constructed emulsions. The average particle size, zeta potential, and BITC retention rate of the emulsions were used as the main evaluation indexes, and confocal laser scanning microscopy was used to test the storage stability of the emulsions (composition: 5 mg/mL protein, 5% oil, 0 to 5 mg/mL BITC, pH 8). After storing at 20 °C for 7 days, the largest particle size of the emulsion at pH 8 increased from 274.27 to 280.82 nm. Storing at higher temperatures had a negative impact on the particle size and BITC retention rate. On the seventh day, the average particle size at 20 and 4 °C was 289.63 nm and 275.67 nm, respectively, and the BITC retention rate at 20 °C (83.30%) was found to be 15.50% lower than that at 4 °C (98.58%). These results demonstrate that the PRPI‐based emulsion system is effective in protecting nutrients and has excellent stability at 4 °C. Practical Application This study provides some useful information for the food industry to develop a nutrient delivery system emulsified with fish roe protein isolate. The properties of the isolated protein and its protective effect on nutrients are discussed.

Pseudosciaena crocea roe protein‐stabilized emulsions for oral delivery systems: In vitro digestion and in situ intestinal perfusion study

“…Therefore, the interfacial proteins distributed on the surface of the droplets during in vitro digestion should be separated and detected. According to previous study, the protein components with molecular weights approximately between 116 and 66.4 kDa had higher proportions of vitellogenin B and vitellogenin (Tang et al., 2019). Compared to PRPI, the low molecular weight bands (55 to 72 kDa) of PRPI‐corn and PRPI‐MCT initial emulsion were relatively shallow (Figure 5).…”

“…The above‐mentioned results confirmed that PRPI‐stabilized emulsions were suitable for storing under nonacidic pH conditions. Based on the previous study, pH 8 was selected as the aqueous phase of the emulsions for the next experiments (Tang et al., 2019).…”

“…PRPI extraction was performed using the Tang et al. (2019) fractional preparation method. Freeze‐dried large yellow croaker roe powder (20 g) was mixed with 0.6 M NaCl (400 mL) and stirred at room temperature for 3 hr.…”

Influence of fish skin gelatin–sodium alginate complex stabilized emulsion on benzyl isothiocyanate stability and digestibilityin vitroandin vivo

“…After being sublimated, the samples were plated with gold under argon atmosphere. Under the condition of accelerating voltage of 2 kV, images were obtained using cryo‐SEM 22 …”

“…Under the condition of accelerating voltage of 2 kV, images were obtained using cryo-SEM. 22 Fluorescence microscopy images Fluorescence microscopy was used to characterize the microstructure of the emulsions at the different digestion phases. The method was slightly modified according to Han et al 23 FSG and corn oil were covalently stained with fluorescein isothiocyanate (FITC) (10 mg mL −1 in dimethyl sulfoxide) and Nile red (10 mg mL −1 in methyl alcohol).…”