Combined Effect of Microencapsulated Horseradish Juice and High-Pressure Treatment on Pork Quality During Storage

High-pressure processing (HPP) is well suited to combine consumer demand for meat products with minimal heat treatment without compromising product safety. In turn, herbs have antioxidant and antimicrobial properties. The aim of this study was to evaluate the application of hurdle technology combining microencapsulated horseradish root and leaf juice with HPP (300 MPa; 15 min) for extending of the raw pork meat shelf life. Water activity (aw), pH, colour, hardness, and micro-biological parameters of meat were evaluated during 21-day storage. Total plate count (TPC) in HPP treated samples was significantly smaller (p < 0.05) compared to untreated samples during storage until the day 14. On day 21, the TPC in processed samples was still slightly lower, however, at this point significance was not established between samples. Water activity dynamics in the HPP-treated microencapsulated pork meat samples differed significantly from other samples. Hardness decreased during storage, but no significant differences were found between samples. The L* values and pH of the meat were not significantly influenced by the added microencapsulated juice, but by high pressure treatment. Treatment with microencapsulated horseradish juice had a positive effect on the TPC and aw of the meat sample.

Effects of Pressure Level and Time Treatment of High Hydrostatic Pressure (HHP) on Inulin Gelation and Properties of Obtained Hydrogels

The aim of this study was the evaluation of the influence of different HHP levels (150 and 300 MPa) and time treatment (5, 10, 20 min) on the gelation and properties of hydrogels with different inulin concentration (15, 20, 25 g/100 g). High-pressure treatment, in tested ranges, induces inulin gels and allows obtaining gel structures even at a lowest tested inulin content (i.e., 15 g/100 g). Selecting the pressure parameters, it is possible to modify the characteristics of the created hydrogels. The use of higher pressure (i.e., 300 MPa) allows to increase the stability of the hydrogels and change their structure to more compressed, which results in higher yield stress, lower spreadability, harder and more adhesive structure. For example, increasing the inulin gelling induction pressure (concentration 20 g/100 g) from 150 to 300 MPa with a time treatment of 10 min resulted in an increase in yield stress from 38.1 to 711.7 Pa, spreadability force from 0.59 to 4.59 N, firmness from 0.11 to 1.46 N, and adhesiveness from −0.06 to −0.65 N. Extending the time treatment of HHP increases this effect, but mainly when higher pressure and a higher concentration of inulin are being used. For example, extension of time treatment at 300 MPa pressure from 5 to 20 min resulted in an increase in yield stress from 774.8 to 1273.8 Pa, spreadability force from 6.28 to 8.43 N, firmness from 1.87 to 2.98 N, and adhesiveness from −0.94 to −1.27 N. The obtained results indicate the possibility of using HHP to create inulin hydrogels tailored to the characteristics in a specific food product.

High Pressure Treatment Modifies Rigid Structure of Myoglobin and Improves Its Digestibility

Objectives Myoglobin is a special globular protein composed of a polypeptides chain and a heme group. Our previous in vitro and in vivo studies have shown that myoglobin is less susceptible to digestion because of its rigid structure. High pressure treatment is gaining more and more popularity in meat industry. To improve the digestibility and nutritional value of myoglobin, the effects of high pressure treatment on the structural and nutritional properties of myoglobin were investigated. Methods Myoglobin was treated during 100–400 MPa for 20 min, spectroscopic techniques and an in vitro digestion model were performed. Results High pressure treatment induced unfolding of globin and dissociation of heme, with an increase in the absorbance of Soret band and a reduction in the intensity of intrinsic and synchronous fluorescence spectra. Some certain changes occurred in the dissociated heme group, as the content of heme and metmyoglobin decreased. The gastric and intestinal digestibility of myoglobin increased as the pressure rose. Conclusions The results indicated that high pressure treatment could be a promising technology to improve digestibility of myoglobin by modifying its structure to improve its nutritional value. Funding Sources This work was supported by the grants from NSFC (32072211).