In this paper, the food-grade gelatin nanoparticles (GNPs) were prepared by a two-step desolvation method and using genipin as a cross-linker. The GNPs with narrow size distribution and good dispersion could be obtained only at pH 12. The effect of the genipin dosage (8–12 wt%) on the GNPs was systematically investigated. The results showed that the cross-linking degree of the GNPs increased with the increasing dosage of genipin, thus leading to a more obvious cross-linking morphology observed from scanning electron microscope (SEM). The obtained GNPs showed a good dispersibility with a size range of 386–438 nm. However, the GNPs cross-linked by 8 wt% genipin dosage revealed a relatively higher size because of the aggregation induced by hydrogen bond. The 10 wt% group had good thermal stability and storage stability. The optical microscopy results showed that the Pickering emulsions (30–50 vol% internal phase) stabilized by the GNPs had good uniformity and stability, even after 30 days of storage time, suggesting that the stable GNPs had great potential in food-grade Pickering emulsions.

Aflatoxin B₁ (AFB₁) is a highly toxic mycotoxin found worldwide in cereals, food, and animal feeds. AFB₁ binds to human serum albumin (HSA) with high affinity. In previous experiments, it has been revealed that reducing the binding rate of AFB₁ with HSA could speed up the elimination rate of AFB₁. Therefore, we examined the ability of quercetin to compete with AFB₁ for binding HSA by fluorescence spectroscopy, synchronous spectroscopy, ultrafiltration studies, etc. It was shown that AFB₁ and quercetin bind to HSA in the same Sudlow site I (subdomain IIA), and the binding constant (K_a) of the quercetin-HSA complex is significantly stronger than the complex of AFB₁-HSA. Our data in this experiment showed that quercetin is able to remove the AFB₁ from HSA and reduce its bound fraction. This exploratory work may be of significance for studies in the future regarding decreasing its bound fraction and then increasing its elimination rate for detoxification. This exploratory study may initiate future epidemiological research designs to obtain further in vivo evidence of the long-term (potential protective) effects of competing substances on human patients.

The water-in-oil (W/O) emulsion with a medium aqueous phase may be limited in food and cosmetics due to its poor stability and high cost. Herein, this work proposed a facile strategy to improve the W/O emulsion stability by introducing gelatin. The influence of different gelatin concentrations (0, 0.5%, 1.0%, 2.0%, and 4.0%) on the stability and properties of W/O emulsions was mainly investigated. Results showed that the obtained emulsions still belonged to W/O emulsions after adding gelatin to the aqueous phase. As the gelatin concentration increased (0~4.0%), the interfacial tension decreased, which is conducive to promoting the interface adsorption of polyglycerol polyricinoleate (PGPR). Furthermore, introducing gelatin also improved the water-holding capacity (WHC) (33.50~6.32%) and viscosity of W/O emulsions and reduced the droplet size (37.47~8.75 μm) of emulsions. The enhanced interfacial adsorption and aqueous gelation induced by gelatin addition promoted the formation of a tight overall emulsion network structure by the interaction between the interfacial adsorbed PGPR, as well as PGPR and gelatin in the aqueous phase. The enhancement of the overall network effectively improved the storage stability (35 d), thermal stability (20 min, 80 °C), and freeze–thaw stability (10 cycles) of emulsions, especially at 4.0% gelatin concentration. Hence, this study can provide guidance for the improvement and regulation of the stabilities of W/O emulsions.

Pineapple peel cellulose nanofibrils (PCNFs) were facilely prepared by the ball milling method assisted by alkali solution (3 wt% NaOH) and a wet grinding medium, using various treated pineapple peels (hot water treatment (WT), bleaching treatment (BT), alkaline treatment (AT), and baleaching–alkaline treatment (ABT)) as raw materials. The structure of the obtained PCNFs (i.e., WT-PCNF, BT-PCNF, AT-PCNF, and ABT-PCNF) was characterized to analyze the influence of component intervention. The results indicated that NaOH-assisted ball milling did not change the crystal structure of cellulose, and the yield and thermal stability of the PCNFs was improved. The average diameters of WT-PCNF, BT-PCNF, AT-PCNF, and ABT-PCNF were 24.16, 21.53, 23.04, and 19.46 nm, respectively, in which BT-PCNF and ABT-PCNF exhibited a higher defibrillating degree and smaller diameter. Particularly, NaOH-assisted ball milling can promote the removal of non-cellulose components. The viscosity and modulus of BT-PCNF were relatively higher due to the presence of residual hemicellulose as a natural linker of fibers. The current research provides insights for simplifying the preparation and functionalization of nanocellulose.