Objective: To develop healthier comminuted meat products to meet consumer demand, the gel properties, rheological properties, microstructure and water distribution of pork meat batters formulated with various amounts of bamboo shoot dietary fiber (BSDF) were investigated.Methods: Different levels of BSDF (0% to 4%) were added to pork batters, and the pH, color, water-holding capacity, texture and rheological properties of pork batters were determined. Then, pork batters were analyzed for their microstructure and water distribution using scanning electron microscopy (SEM) and low-field nuclear magnetic resonance (LF-NMR).Results: Compared with the control, BSDF addition into meat batters showed a significant reduction in L*-value and a significant increase in b*-value (p<0.05). BSDF addition of up to 4% reduced the pH value of pork batters by approximately 0.15 units; however, the cooking loss and expressible water loss decreased significantly (p<0.05) with the increased addition of BSDF. The hardness and gel strength were noticeably enhanced (p<0.05) as the content of BSDF increased. The rheological results showed that BSDF added into pork batters produced higher storage modulus (G′) and loss modulus (G″) values. The SEM images suggested that the addition of BSDF could promote pork batters to form a more uniform and compact microstructure. The proportion of immobilized water increased significantly (p<0.05), while the population of free water was decreased (p<0.05), indicating that BSDF improved the water-holding capability of pork batters by decreasing the fraction of free water.Conclusion: BSDF could improve the gel properties, rheological properties and water distribution of pork meat batters and decrease the proportion of free water, suggesting that BSDF has great potential as an effective binder in comminuted meat products.

The effect of bamboo shoot dietary fibre (BSDF) (0%-4%) on the gel quality, protein thermal stability and secondary structure of pork salt-soluble proteins (SSP) was investigated. The water holding capacity (WHC), breaking force and particle size were increased with the addition of 2% BSDF. Differential scanning calorimetry (DSC) analysis indicated that the addition BSDF changed the thermal denaturation temperature of myosin tail and actin, and led to the disappearance of myosin head as the increase of BSDF up to 4%. SDS-PAGE showed that the band intensity of actin was obviously enhanced by the addition of BSDF. Fourier transform infrared (FTIR) spectroscopy showed that BSDF could affect the protein secondary structure. The α-helix content was significantly decreased and the β-sheet content was significantly increased (P<0.05). In conclusion, BSDF could improve gel quality of salt soluble proteins and has a potential to be applied in meat products.

Ultrasound treatment can improve enzymolysis efficiency by changing the amounts of sulfhydryl groups (SH) and disulfide bonds (SS) in protein. This paper proposes an in-situ and real-time monitoring method for SH and SS during ultrasound application processes using a miniature near-infrared (NIR) optical fiber spectrometer and a chemometrics model to determine the endpoint of ultrasonic treatment. The results show that SH and SS contents fluctuated greatly with the extension of ultrasonic time. The optimal spectral intervals for SH content were 869–947, 1207–1284, 1458–1536 and 2205–2274 nm, the optimal spectral intervals of SS content were 933–992, 1388–1446, 2091–2148 and 2217–2274 nm. According to the optimal spectral intervals, the synergy interval partial least squares (Si-PLS) and error back propagation neural network (BP-ANN) for SH, SS contents were established. The BP-ANN model was better than the Si-PLS model. The correlation coefficient of the prediction set (R_p) and the root mean square error of prediction (RMSEP) for the BP-ANN model of SH were 0.9113 and 0.38 μmol/g, respectively, the R_p² and residual prediction deviation of SH were 0.8305 and 2.91, respectively. For the BP-ANN model of SS, the R_p and the RMSEP were 0.7523 and 6.56 μmol/g, respectively. The R_p² and residual prediction deviation (RPD) of SS were 0.8305 and 2.91, respectively. However, the R_p² and RPD of SS was 0.5660 and 1.64, respectively. This work demonstrated that the miniature NIR combined with BP-ANN algorithms has high potential for in-situ monitoring of SH during the ultrasonic treatment process, while the spectral prediction model of SS needs to be further developed.