Thermal and Modern, Non-Thermal Method Induction as a Factor of Modification of Inulin Hydrogel Properties.

The aim of the study was to compare the properties of inulin hydrogels obtained with different methods, e.g., the traditional-thermal method and new, non-thermal methods, used in food production, like ultrasonic, high-pressure homogenization (HPH), and high hydrostatic pressures (HHPs). It was found that each of the compared induction methods allowed for obtaining inulin hydrogels. However, the use of non-thermal induction methods allows for obtaining a gel structure faster than in the case of thermal induction. In addition, hydrogels obtained with new, non-thermal methods differ from gels obtained with thermal treatment. They were characterized by higher stability (from 1.7 percent point-of-stability parameters for HHP 150 MPa to 18.8 for HPH II cycles) and in most cases, by improved microrheological properties-lower solid-liquid balance toward the solid phase, increased elasticity and viscosity indexes, and lowering the flow index. The gels obtained with the new, non-thermal method were also characterized by a more delicate structure, including lower firmness (the differences between thermal and non-thermal inductions were from 0.73 N for HHP at 500 MPa to 2.39 N for HHP at 150 MPa) and spreadability (the differences between thermal and non-thermal inductions were from 7.60 Ns for HHP at 500 MPa to 15.08 Ns for HHP at 150 MPa). The color of ultrasound-induced inulin gels, regarding the HPH and HHP technique, was darker (the differences in the L* parameter between thermal and non-thermal inductions were from 1.92 for HHP at 500 MPa to 4.37 for 10 min ultrasounds) and with a lower a* color parameter (the differences in the a* parameter between thermal and non-thermal inductions were from 0.16 for HHP at 500 MPa to 0.39 for HPH II cycles) and b* color parameter (the differences in the b* parameter between thermal and non-thermal inductions were from 1.69 for 5 min ultrasounds to 2.68 for HPH II cycles). It was also found that among the compared induction methods, the high-pressure technique has the greatest potential for modifying the properties of the created inulin hydrogels. Thanks to its application, depending on the amount of applied pressure, it was possible to obtain gels with very different characteristics, both delicate (i.e., soft and spreadable), using HHP at 150 MPa, and hard, using HHP at 500 MPa, the closest in characteristics to gels induced with the thermal method. This may allow the properties of hydrogels to be matched to the characteristics of the food matrix being created.

Editorial on the Special Issue "Novel Gels for Food Product Development".

Recently gels have gained significant attention in the food industry due to their unique properties and potential applications [...].

Quality Aspects of Designing Prohealth Liver Sausages Enriched with Walnut Paste.

The aim of the study was to determine the influence of enriching liver sausages with different levels of walnut paste on the quality properties of this product. Sausages were produced with 5, 10, 15, 20, and 25% amount additions of walnut paste and without the addition of nuts (control product). It was found that walnut paste, especially when introduced at an amount >15%, was a component that limited thermal losses and significantly modified the characteristics of liver sausages. The addition of walnut paste also increased the fat content of liver sausages by two−three times, which was one of the factors that weakened their structure, including lowering their compression, shear, and penetration force but increasing their spreadability. Moreover, the addition of walnut paste at an amount of ≥20% resulted in the products having a slightly different color, with lower values for the a* color parameter. Such changes were assessed as a favorable modification to the product, increasing its overall desirability, especially with the addition of walnut paste at the level of 20%. Walnut paste can therefore be a valuable ingredient that allows for the development of a health-promoting product with improved quality features. However, with the addition of a walnut paste at an amount of 25%, it is necessary to take into account the more rapid and unfavorable fat changes that occur during the storage of the liver sausages, as indicated by about 50% higher TBARS values (compared to the control product).

A Comparative Evaluation of the Structural and Biomechanical Properties of Food-Grade Biopolymers as Potential Hydrogel Building Blocks.

The aim of this study was to conduct a comparative assessment of the structural and biomechanical properties of eight selected food-grade biopolymers (pea protein, wheat protein, gellan gum, konjac gum, inulin, maltodextrin, psyllium, and tara gum) as potential hydrogel building blocks. The prepared samples were investigated in terms of the volumetric gelling index, microrheological parameters, physical stability, and color parameters. Pea protein, gellan gum, konjac gum, and psyllium samples had high VGI values (100%), low solid−liquid balance (SLB < 0.5), and high macroscopic viscosity index (MVI) values (53.50, 59.98, 81.58, and 45.62 nm−2, respectively) in comparison with the samples prepared using wheat protein, maltodextrin, and tara gum (SLB > 0.5, MVI: 13.58, 0.04, and 0.25 nm−2, respectively). Inulin had the highest elasticity index value (31.05 nm−2) and MVI value (590.17 nm−2). The instability index was the lowest in the case of pea protein, gellan gum, konjac gum, and inulin (below 0.02). The color parameters and whiteness index (WI) of each biopolymer differed significantly from one another. Based on the obtained results, pea protein, gellan gum, konjac gum, and psyllium hydrogels had similar structural and biomechanical properties, while inulin hydrogel had the most diverse properties. Wheat protein, maltodextrin, and tara gum did not form a gel structure.

Effect of Differentiated Relative Humidity of Air on the Quality of Traditional Speciality Guaranteed "Krakowska Sucha Staropolska" Sausage.

The aim of the study was to determine the effects of air relative humidity (RH: 60 and 80%) during the drying process of "krakowska sucha staropolska" (KSS) sausages on selected quality characteristics. The composition and production process of KSS sausages complied the requirements of traditional specialities guaranteed. It was found that the use of lower RH of drying air allowed a time reduction of 20%. Lowering the RH of air during the drying process did not affect the cross-sectional colour and odour of the sausages, colour components, TBARS values, protein, fat and salt content. However, the acceleration of the drying process resulted in very dried outer layers and less dry interior of KSS sausages. As a result, the sausages had lower scores in the sensory evaluation of hardness and overall acceptability. For this reason, shortening the drying process of sausages by using air with lower relative humidity is not recommended.

Sodium Alginate and Chitosan as Components Modifying the Properties of Inulin Hydrogels.

The aim of the study was to investigate the influence of addition of sodium alginate (SA) and chitosan (CH) on the properties of inulin hydrogels. Inulin hydrogels (20 g/100 g) containing various additions (0.0, 0.1, 0.3, and 0.5 g/100 g) of SA and CH were produced. The hydrogels' properties were assessed based on the volumetric gel index, microstructure, yield stress, texture, stability, and color parameters. According to the findings, the inclusion of these polysaccharides had no influence on the gelation ability of the inulin solution. The physical properties of the hydrogels containing SA or CH differed from hydrogels containing only inulin (INU). The obtained microstructural pictures revealed that the addition of SA and CH resulted in the formation of hydrogels with a more compact, smooth, and cohesive structure. Consequently, they had higher yield stress, strength, and spreadability values than INU hydrogels. The addition of chitosan in comparison with sodium alginate also had a greater effect in strengthening the structure of hydrogels, especially at the level of 0.5 g/100 g. For example, the addition of this amount of SA increased the yield stress on average from 195.0 Pa (INU) to 493.6 Pa, while the addition of CH increased it to 745.3 Pa. In the case of the strength parameter, the addition of SA increased the force from 0.24 N (INU) to 0.42 N and the addition of CH increased it to 1.29 N. In the case of spreadability this increase was from 2.89 N * s (INU) to 3.44 N * s (SA) and to 6.16 N * s (CH). Chitosan also caused an increase in the stability of inulin hydrogels, whereas such an effect was not observed with the addition of sodium alginate. The gels with the addition of SA and CH also had significantly different values of color parameters. Inulin-alginate hydrogels were characterized by higher values of the color parameter a *, lower values of the color parameter b *, and in most concentrations higher values of the color parameter L * compared to inulin-chitosan hydrogels. Based on the collected data, it can therefore be concluded that through the addition of sodium alginate and chitosan, there is a possibility to modify the properties of inulin hydrogels and, consequently, to better adapt them to the characteristics of the pro-health food products in which they will be used.

Changes in the microbiological quality and content of biogenic amines in chicken fillets packed using various techniques and stored under different conditions.

The aim of this study was to determine the biogenic amines (BAs) formed in chicken breast meat packaged using different techniques (AP, Hi-O2-MAP or VP) during the storage under different conditions (cold room or display case), to correlate the microbiological quality (TPC, LAB, Pseudomonas spp. and Enterobacteriaceae) of chicken meat with BAs formation and to assess the suitability of selected biogenic amines as indicators of chicken meat spoilage. The initial TPC of chicken fillets was 2.57-3.04 log cfu/g. Over time a systematic significant (p ≤ 0.05) increase in TPC was observed to >7.5 log cfu/g (AP and VP; display case) determined on day 9. It was found that cadaverine and tyramine dominated in quantitative terms in chicken fillets, regardless of packaging technique and storage conditions (166.00 mg/kg in AP meat in cold room on day 9 and 175.03 mg/kg on day 9 in MAP meat in display case, respectively). Taking into account the BAI, high and significant (p ≤ 0.05) correlation coefficients (from 0.51 to 0.95) were obtained with all analyzed indicators of microbiological quality. The concentration of cadaverine, putrescine contents or BAI can potentially serve as chemical quality indicator for freshness of chicken meat.

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.

Applications of Biosensors for Meat Quality Evaluations.

The aim of this study was to apply biosensors in the assessment of meat quality. The research was carried out on 20 samples of the Longissimus muscle obtained from pork of Polish Landrace and Polish Large White hybrids of fattening pigs. In the samples, 48 h after slaughter pH values, color parameters in the CIE system (L* a* b*), the volume of natural drip loss and intramuscular fat content were measured. The commercially available biosensor Accutrend Plus was used to measure glucose, triglycerides and lactic acid in meat juice. Significant (p ≤ 0.05) relationships between glucose, triglycerides, lactic acid levels and pork quality characteristics, i.e., pH (r = -0.62; r = -0.78; r = -0.68 respectively), natural drip loss and (r = 0.57; r = 0.58; r = 0.49), color parameters as L*, a* and b* (r = from 0.47 to 0.79) were demonstrated. The study showed a negative correlation between the intramuscular fat content and acidification of muscle tissue (r = -0.49), and a positive one with the brightness of color (r = 0.46). The results of the canonical analysis show that the measurement of all three metabolites in muscle juice allows the evaluation of the technological quality of meat with an accuracy of 86.54% (Rc = 0.93, p < 0.01).

Performance and Meat Quality of Intrauterine Growth Restricted Pigs.

Intrauterine growth restricted (IUGR) pigs are characterized by high perinatal mortality and dysfunction of internal organs, adipose, and muscle tissues. However, little is known about the post-weaning performance and meat quality of the IUGR pigs. The aim of this study was to compare normal pigs and pigs with IUGR from birth until slaughter, also with respect to their meat quality. Pigs with the IUGR achieved lower slaughter weight but did not differ significantly from normal pigs in terms of their meat content. The IUGR did not negatively affect the culinary quality of the obtained meat, including its content of basic chemical components and energy value, as well as hardness, chewiness, cohesiveness, elasticity, and penetration force. The meat of the IUGR pigs, when compared to the meat of normal pigs, was characterized by higher pH, lower EC (Electrical Conductivity) and drip loss; it was also tenderer and obtained higher scores in sensory evaluation of taste, smell, and general desirability. Therefore, such raw material can be appreciated by the consumers and can be used for the production of culinary portions similarly to the raw material obtained from normal pigs.

Addition of Selected Plant-Derived Proteins as Modifiers of Inulin Hydrogels Properties.

The aim of the study was to determine the effects of pea and soy protein addition (1, 3, 6 g/100 g) on inulin hydrogels properties. Inulin hydrogels (20 g/100 g) were obtained by thermal induction. It was stated that tested plant protein might be used as a modifier of inulin hydrogels properties. The addition of pea and soy protein to inulin hydrogels resulted in networks with more a compact and homogeneous structure. The increase of the protein concentration caused the structure of the hydrogels to get smoother, more cohesive, and less granular. Pea and soy protein addition (3-6 g/100 g) to hydrogels allowed to obtain higher values of yield stress, texture (firmness, adhesiveness) and spreadability parameters. At a protein concentration of 6 g/100 g, the firmness of inulin hydrogels was seven times higher for those with pea protein (1.87 N) and ten times higher for those with soy protein (2.60 N) compering to the control hydrogel (0.24 N). The transmission profiles of hydrogels with incorporated 6 g/100 g of soy proteins showed the slowest motion of the particles, which indicates the highest stability of gel. As the concentration of protein addition increased, a reduction in the lightness was observed.

Estimation of Chemical Composition of Pork Trimmings by Use of Density Measurement-Hydrostatic Method.

This study aims to determine the possibility of using density measurements by using the hydrostatic method for the estimation of the chemical composition of pork. The research material included 75 pork samples obtained during industrial butchering and cutting. The density measurements were performed using the hydrostatic method based on Archimedes' principle. The meat samples were minced, and the content of the basic chemical components in them was determined. The usefulness of density measurement using the hydrostatic method in chemical composition estimation was determined by analyzing the correlation for the entire population, and after grouping the samples with a low (<15%), medium (15-25%), and high (>25%) fat content. High (in absolute value) coefficients of correlation between the meat density and the content of water (0.96), protein (0.94), and fat (-0.96) were found based on the results obtained. In order to achieve higher accuracy of the estimation, the applied regression equations should be adjusted to the presumed fat content in the meat. The standard error of prediction (SEP) values ranged from 0.67% to 2.82%, which indicates that the calculated estimation accuracy may be sufficient for proper planning of the production. Higher SEP values were found in fat content estimation and the lowest ones were found in protein content estimation.

Chemical Composition of Edible Ostrich Offal.

The offal (hearts, stomachs, and livers) of 24 African ostriches (Strutio camelus var. domesticus) from Polish farms were used in this study. Offal were taken directly from the production line; they were weighed and their water, fat, protein, ash and total collagen contents were determined. Ostrich hearts and stomachs were found to have high protein (18.1% and 19.0%, respectively) and low fat content (2.0% and 0.9%, respectively), typical of lean meat. Thus, the offal could be used in processed offal products or in pet food. Ostrich livers had slightly lower protein content (16.6%) and significantly higher and diverse fat content (4.4-28.4%). Heavier livers had significantly (P<0.05) higher fat and lower protein, water, and ash content. The utilization of ostrich liver should be preceded by classification of its fat content.

The effect of pale, soft and exudative meat on the quality of canned pork in gravy.

The objective of the study was to evaluate the use of PSE meat in the production of sterilized pork type canned meat in its own gravy. Canned meat products were produced with 50% of PSE meat as well as with 100% PSE meat, and compared with canned meat products of good quality (RFN). It was found that decreased quality of PSE meat had a small impact on the quality of canned meat products. Substitution of both 50% as well as the total quantity of RFN meat with PSE meat did not affect the course of the sterilization process, neither increase the quantity of excreted fat and jelly in canned meat. It also had no effect on the instrumentally-measured parameters of texture and neither did it affect different sensory quality features, including the overall desirability of the product. The PSE canned meat product were characterized by higher values of L* and b* color parameters.

A Potential Use of 3-D Scanning to Evaluate the Chemical Composition of Pork Meat.

UNLABELLED: The aim of this study was to determine the possibility of 3-D scanning method in chemical composition evaluation of pork meat. The sampling material comprised neck muscles (1000 g each) obtained from 20 pork carcasses. The volumetric estimation process of the elements was conducted on the basis of point cloud collected using 3-D scanner. Knowing the weight of neck muscles, their density was calculated which was subsequently correlated with the content of basic chemical components of the pork meat (water, protein and fat content, determined by standard methods). The significant correlations (P ≤ 0.05) between meat density and water (r = 0.5213), protein (r = 0.5887), and fat (r = -0.6601) content were obtained. Based on the obtained results it seems likely to employ the 3-D scanning method to compute the meat chemical composition. PRACTICAL APPLICATION: The use of the 3-D scanning method in industrial practice will allow to evaluate the chemical composition of meat in online mode on a dressing and fabrication line and in a rapid, noninvasive manner. The control of the raw material using the 3-D scanning will allow to make visual assessment more objective and will enable optimal standardization of meat batches prior to processing stage. It will ensure not only the repeatability of product quality characteristics, but also optimal use of raw material-lean and fat meat. The knowledge of chemical composition of meat is essential due to legal requirements associated with mandatory nutrition facts labels on food products.