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ABSTRACT: This study aimed to investigate the effects of phosphorylated-ovalbumin (P-OVA) at different concentrations (0.5% and 1.0%) on the gel properties of pork myofibrillar protein (MP). The results showed that the textural properties such as gel hardness, cohesiveness, springiness and chewiness were improved with P-OVA addition at 0.5%. The water holding capacity (up to 75.89%) and gel strength (up to 168.56 g·mm) of MP gel were markedly increased after P-OVA addition. The absolute value of zeta potential reached 13.85 mV and maximum hydrophobicity (15.2 μg) resulted from the addition of 0.5% P-OVA. The storage modulus (G’) and loss modulus (G’’) of MP gel were significantly increased from 50°C, and the G’ and G’’ significantly increased after 1.0% P-OVA addition, evidencing that the cross-linking effect of MP protein gel was enhanced. In addition, the P-OVA addition improved the structure of MP gel protein by reducing the α-helix, while increasing the β-sheet and the r-value (the ratio between two ultraviolet second-derivative peak-to-trough distances), which further promoted the uniform and compact gel network structure. This work demonstrated that P-OVA is a highly effective modifier that significantly improves the quality of MP gel. From a view of practice, 0.5% P-OVA is the optimal addition amount.

The effects of different contents of mung bean on microstructure, cooking property, hypoglycemic activity and in vitro starch digestion of extruded buckwheat noodles were studied. The results demonstrated that as the increase of mung bean content, the cooking loss of the noodles decreased from 19.26 % to 14.59 %, the estimated glycemic index (eGI) decreased from 85.17 to 69.66, and the content of resistant starch (RS) content increased from 39.32 % to 55.45 %; Furthermore, the α-glucosidase and α-amylase inhibitory activities were significantly enhanced; however, the overall sensory attributes did not change significantly. Afterwards, XRD and FTIR analyses revealed that the addition of mung bean promoted the formation of starch-lipid complexes and improved the short-range structural order of starch; Additionally, scanning electron microscopy (SEM) results indicated that as the content of mung bean increased, the pores within the extruded buckwheat noodle gradually became smaller, and the number of pores increased gradually, contributing a more complete network structure, which favors the formation of gels with enhanced mechanical properties. In conclusion, the comprehensive quality of extruded buckwheat noodles with the addition of mung bean was effectively improved.

In present study, Rhizopus chinensis 12 mixed fermentation with Bacillus sp. DU-106 were performed to improve the quality and flavor of Semen Sojae Praeparatum (SSP). The levels of physicochemical characteristics, bioactive compounds, free amino acids, and volatile components during the mixed fermentation process were monitored. Compared to SSP fermented only with R. chinensis 12, the levels of physicochemical characteristics were not obviously changed after mixed fermentation. However, thrombolytic enzyme activity and soy isoflavone content after mixed fermentation were significantly higher when compared to those of SSP fermented only with R. chinensis 12, and reached to 3927.84 IU/g and 3.91 mg/g, respectively. The amount of bitter amino acids and umami amino acids after mixed fermentation slightly lower than those of SSP fermented only with R. chinensis 12. The contents of flavor composition were considerably altered after mixed fermentation, of which, the pyrazine prevailed in SSP fermented only with R. chinensis 12, while, alkane predominated in SSP after mixed fermentation. Overall, the Rhizopus chinensis 12 mixed fermentation with Bacillus sp. DU-106 contributed to improve the thrombolytic activity, free amino acid content, and flavors of SSP.

A flexible wipe paper for rapid nondestructive detection of ferbam residues on the surface of fruits and vegetables by surface-enhanced Raman scattering (SERS) was prepared using filter paper as the substate by a simple soaking method. The synthesis and storage conditions were optimized to ensure that the SERS method has excellent performance. The results showed that concentration factor of silver nanoparticles (AgNPs), soaking time in AgNP solution and drying method greatly affected the performance of the SERS wipe paper. The performance under the condition of soaking for 8 h in a 5-fold concentrate of AgNP solution was significantly better than that under other conditions. The SERS wipe paper prepared by vacuum drying had better performance that those prepared by other drying methods. After 9 days of storage at −20 ℃, the optimized substrate retained approximately 50% of the original peak value. Besides, it exhibited good sensitivity, uniformity, and repeatability. The limit of detection (LOD) for ferbam on a glass plate was 4.07 × 10-6 mg/mL, and the LOD for ferbam on the surface of spinach and nectarine were 0.043 and 0.062 mg/kg, respectively. This study provides an excellent basis for the development and utilization of SERS wipe paper.