The viability of probiotics is strictly influenced by the production, storage, and digestion, while microencapsulation is a technology that can protect them against harsh environments. In this study, the impact of different core-to-wall ratios and wall material formulations on physical properties and the cell number of the microcapsules were investigated. The samples with core-to-wall ratio 1:1 have a significantly higher cell number, encapsulation efficiency, and bulk density than samples with core-to-wall ratio 1:1.5. The yields of the encapsulation method were changes in the opposite direction. Meanwhile, core-to-wall ratios and formulation have a significant effect on the cell number of the microcapsules during the in vitro SGJ test, whereas time, core-to-wall ratios, and formulation have a similar influence in the in vitro SIJ test. Moreover, probiotic apple juices stored at 4 °C for 6 weeks kept the highest cell number at the end. Furthermore, probiotic apple juices fortified by microcapsules coated with WP:DWP 1:1 in core-to-wall ratio 1:1 and stored at 4 °C for 4–8 weeks exhibited a significantly lower pH value. In summary, both whey proteins and denatured whey proteins are as good as coating material for microencapsulation of probiotic bacteria Lactobacillus plantarum 299v strains. These microcapsules have high potential in the production of probiotic apple juice even by fermentation or fortification methods.
Egg yolk undergoes an irreversible gelation process at temperatures below −6 °C, which greatly impairs its application and increases its apparent viscosity. This work was aimed to investigate the effect of salt and pH in preventing the gelation of frozen-thawed egg yolk. Before freezing, 5% of salt was added into the pasteurized liquid egg yolk, then pH was adjusted to different levels (5.7, 6.0 and 6.3) with citric acid. After that, the yolk was stored at −18 °C for four weeks. Rheological and thermal properties of the fresh and frozen-thawed egg yolk were measured. In addition, the colour, turbidity and emulsifying properties were also determined. The results showed that pH of all samples increased during frozen storage, but at different rates. The combination of 5% of salt and pH at 6.0 and 6.3 could prevent the gelation, resulting in rheological properties more like the fresh liquid egg yolk. In addition, emulsifying properties also obtained better results for treated yolk. Moreover, L* value of treated egg yolk was higher before freezing and became lower after storage compared to control. The results of this work found that the combination of 5% of salt and adjusted pH could prevent the gelation of frozen-thawed liquid yolk.
Currently, there is a growing demand for ready-to-eat, prepared, high-quality, preservative-free products. However, the shelf-life of these products is often so short that a relatively high percentage of these products cannot be sold and end up as food waste. In this study, pork loin with different marinades (paprika and herbs) was treated with different high hydrostatic pressures (0 MPa, 300 MPa, 450 MPa and 600 MPa) and a bioactive component (piperine) and then the quality of the meat was examined after 0, 4, 8, 12 and 14 days of cold storage. Changes were monitored using color, pH, texture and microbiological analyses. Both pressure, piperine enrichment, storage time and the interactions of different factors had a significant effect on the quality of the loin samples with different marinades. Due to the denaturation of myoglobin, meat slices were less red and lighter after HHP treatment. The addition of piperine reduced this lightness. The pH increased with increasing pressure and decreased with storage time. HHP treatment significantly increased meat hardness, with samples treated at 600 MPa being 19% harder than those treated at 450 MPa. Microbiological results indicated that HHP at 450 MPa and 600 MPa effectively reduced anaerobic total live plate counts, ensuring satisfactory sensory and microbiological quality throughout storage. Piperine fortification also resulted in a more favorable microbiological status during storage without any perceptible change in quality properties during storage. These findings underscore the effectiveness of HHP and piperine enrichment in enhancing the safety and quality of marinated meats.
In the last few decades, convenience has become one of the most important factors for consumers. Therefore, food products that take a short time to prepare are gaining in popularity. The aim of this study was to develop a gluten-free egg-pie product which is quick-frozen in pre-baked form and remains usable for a long time. Besides, it satisfies various consumer needs while remaining sustainable by not having a great impact on the environment. A dough containing rice, millet, and buckwheat flour was developed. The fillings also appeared in unflavored and flavored form (spinach onion, cheese) with and without increased egg white content. Acceptance of the product was measured by sensory test. Texture and dry matter content measurement, triangular test, and color measurement were performed to track changes through six months of frozen storage. The stored pies’ hardness declined for three months, then doubled the original value at the end of the frozen storage. The stored pies hardness declined for three months (from 10.76 ± 1.78 and 11.22 ± 1.47 N to 8.52 ± 1.74 and 9.91 ± 1.16 N), then doubled the original value at the end of the frozen storage (21.69 ± 2.55 and 19.62 ± 1.67 N). The dry matter content showed increasing tendency. Results of the triangular tests showed that the stored flavored pies were less distinguishable from freshly baked ones than the unflavored egg-pies. Color measurement showed that the fillings of the pies were darkening during the frozen storage. Consumer liking test showed values between 6.52 ± 1.76 and 7.56 ± 1.2 on a 9-point hedonic scale. Color measurement showed that the fillings of the pies were darkening during the frozen storage, and the lightness values decreased from 90.17 ± 0.06 and 90.53 ± 0.11 to 81.43 ± 0.41 and 83.22 ± 0.87 in six months. Results generated in this study suggest that consumers’ acceptance was high, though results of penalty analysis showed that more flavorings would increase the overall acceptability.
In our experiment, the effect of electrical and CO2 stunning on pork meat quality attributes was studied. A total of thirty PIC337 female pigs were allocated to two equal groups which were stunned electrically (50 Hz, 210 V, 2.6 A, 15 s) or by CO2 (85 V% CO2, 15 V% O2, 90 s) and slaughtered at a commercial slaughterhouse. For 24 h post mortem, the carcass m. gluteus medius (GM) was used to evaluate meat quality attributes such as pH, color, hardness, water holding capacity (WHC), and total pigment content, and meat classification was also carried out. The CO2 stunning resulted in muscle with significantly lower pH (p < 0.01) and poorer water holding capacity (p < 0.05) compared to electrical stunning. The GM of pigs stunned electrically showed significantly increased lightness (L*) and redness (a*) (p < 0.05) compared to CO2-stunned. The time course of development of rigor mortis was similar for both stunning methods. Pale, soft, exudative (PSE) or dark, firm, dry (DFD) meat defects were not observed. Based on total pigment content, stunning methods did not significantly affect the amount of removable blood.
15 December 2025 in Progress in Agricultural Engineering Sciences
In the present study, egg white suspensions (12 w/v%) were HHP-treated at 300, 400, 450, 500, 550 and 600 MPa for 5 min. The effects of HHP treatment on the colour, rheological properties, microbiological status and digestibility of the samples was investigated. Colorimetric analysis revealed increased lightness (L*) and yellowness (b*), with decreased redness (a*), indicating enhanced visual appeal. The rheological evaluation at 500 MPa and above showed a transition from dilatant to pseudoplastic behaviour, which is favourable for food processing due to improved flow under shear stress. SDS-PAGE and in vitro digestion confirmed extensive protein denaturation and enhanced digestibility—especially the complete hydrolysis of ovotransferrin—potentially reducing allergenicity and increasing nutrient bioavailability. Microbiologically, treatments at 500–600 MPa significantly reduced mesophilic aerobic bacteria and extended shelf-life, maintaining safety over 44 days. Overall, HHP-treated egg white demonstrates promising potential as a functional ingredient in safe, nutritious, and technologically adaptable food products.