Breaking Deformation Research Articles

Carrageenans and alginate effects on properties of combined pressure and temperature in fish mince gels

Sulphated polysaccharides (kappa- and iota-carrageenan) and sodium alginate added to blue whiting mince were subjected to three different pressure/heat treatments in order to determine the functionality of each one in mince gel. The effect of the gelling treatment was largely dependent on the hydrocolloid used. In general, gelation at atmospheric pressure induced gels that were more adhesive, harder (except in the case of iota-carrageenan) and yellower, and less cohesive. Lower pressure conditions (200 MPa, 10°C, 10 min) produced more cohesive gels with higher breaking deformation and lower elasticity; these gels also had the highest values of work of penetration (especially those containing iota-carrageenan). Higher pressure conditions (375 MPa, 37°C, 20 min) induced gels with the lowest hardness; all other characteristics were similar in some cases to pressurized gels at lower gelling conditions and in others to heat-induced gels. The carrageenans (iota or kappa) appeared to form a reticular structure in the heat-induced gels, which was not observed with alginate. In the pressurized gels, iota-carrageenan was in globular form, indicating that it had not gelled; kappa-carrageenan, on the other hand, formed small, fine reticular structures. Alginate formed a fine, dense network in the higher treatment conditions, but this was not observed in the lower treatment conditions. From a technological standpoint, the composite system offers new potential, due not only to the added hydrocolloid but also to the treatment applied.

Effects of hydrocolloids and high-pressure-heating processing on minced fish gels

Multivariate statistical methods were applied to data sets of measured gelling properties of blue whiting mince with several hydrocolloids added (locust bean gum, guar gum, xanthan gum, carboxymethylcellulose, ι-carrageenan, κ-carrageenan or alginate) induced under different pressure-time-temperature gelling conditions. The main differences between gels were attributed to the process; all the gels were classified in three clusters on the basis of gelling treatment: (1) high-pressure at moderate heating, (2) high-pressure at cold temperature and (3) heating at atmospheric pressure. Cluster 1 was characterized by very elastic, light gels with high water holding capacity. In cluster 2, gels presented high puncture test properties (breaking deformation, breaking force, work of penetration) and high cohesiveness and water holding capacity. Cluster 3 gels presented low penetration test properties and cohesiveness; high adhesiveness and hardness; high lightness and yellowness. Each cluster was subdivided to describe the gel properties between the hydrocolloid groups, attributing the differences mainly to yellowness (b*), breaking deformation, breaking force and work of penetration.

Mince gels with hydrocolloids and salts: composition/function relationships and discrimination of functionality by multivariate analysis

Multivariate statistical methods were applied to gelling properties (mechanical, water holding capacity, and color) of blue whiting mince with varying combinations of hydrocolloids and different ranges of salts. Factor analysis identified five principal components which accounted for over 90% of the data variance. The role of the salts in the various functional properties was independent of the hydrocolloid used. The most important contributor was CaCl2, present in the first three factors, which negatively affected most of the target parameters and positively influenced elasticity and lightness. KCl and NaCl appeared to have a less drastic effect on the studied properties; they presented high factor loadings in the fourth and fifth principal components, respectively. Three clusters were obtained: 1) locust bean and guar gum; 2) carrageenans (iota and kappa), carboxymethylcellulose and sodium alginate; and 3) xanthan gum. Basically, breaking deformation and hardness were the variables that best discriminated in 96.4% of cases.

Pressure-induced gel properties of fish mince with ionic and non-ionic gums added

Various non-ionic gums (locust bean and guar) and anionic gums (xanthan and carboxymethylcellulose) were added to blue whiting mince and subjected to gelling treatments in different combinations of pressure–time–temperature in order to determine their behaviour in mince gel. The treatment of gelation induced more drastic effects that the kind of gums added in the fish mince. Heat treatment at atmospheric pressure generally originated higher adhesiveness and yellowness ( b*). High pressure at cold temperatures induced the highest cohesiveness and breaking deformation (except with xanthan) and the lowest elasticity, and high pressure at moderate heating generally produced the lowest hardness. The organization of the gum generally differed according to the treatment: filamentous structures forming under pressure and aggregates forming with heat (except xanthan). Water holding capacity increased under pressure in gels containing ionic gums. Overall, the combination of hydrocolloid and gelling treatment appeared to offer increased technological possibilities in that it produced a wider range of rheological characteristics, water holding capacity and colour in the gelled product.

Pressure distribution measurement in biting surimi gels with molars using a multiple-point sheet sensor.

The bite force of three surimi gels with molars was measured in the mouth using a multiple-point sheet sensor. A peak force appeared at the breaking point of each sample, and then the force increased again, accompanied by a decrease in the opening between the upper and lower teeth. Low values in the peak force, pressure, and time at the first peak, the time at which the maximum contact area was engaged, impulse, and slope of bite curve were observed in samples with low breaking force and low breaking deformation found by the mechanical measurement of gel strength, and with less toughness in the sensory assessment. The duration of the bite force, the second peak time, and active bite pressure at the second peak did not change with a change in the surimi texture. The active pressure at the breaking point of each gel was affected by gel strength, while that at the second peak was independent of the gel strength.

Relation between external loading and its images in the Il'yushin space at finite strains

Experimental results on combined loading of tubular specimens at finite strains are not uniquely interpreted. Differential relations between deformation and strain-vector variations assigned to different bases of the Il'yushin space were established. The relationships obtained are needed to develop experimental programs for studying properties of materials at large strains. The differences appearing upon realization of a preset broken deformation trajectory were analyzed as an example. External loading patterns for a given trajectory in fixed, rotational, and polar bases were set.

INFLUENCE OF WASHING PARAMETERS ON THE CHARACTERISTICS OF HORSE MACKEREL (TRACHURUS TRACHURUS) MINCE

The objective of the present work was to establish the optimal conditions of pH, hardness and tetrasodium pyrophosphate (TSPP) in the leaching water used in the preparation of washed horse mackerel (Trachurus trachurus) mince to obtain a product with the best gelation characteristics. Total protein content and water holding capacity were affected by the wash water pH. The folding test, the breaking deformation and the water holding capacity declined considerably for pH values less than about 6.5. On the other hand, gel strength, breaking force and hardness were significantly influenced by TSPP concentration but not by pH water hardness influenced the breaking deformation and protein content of minces but not in its hardness, cohesiveness and elasticity. From these results the best conditions for leaching water to be used with horse mackerel mince seem to be pH 6.5, 0.0–2.Og TSPP/L and 50mg CaCO3/L.

Chilled storage of high pressure and heat-induced gels of blue whithing (Micromesistius poutassou) muscle

Microbiological, rheological and chemical characteristics were examined in gels made from the muscle of blue whiting (Micromesistius poutassou) and subjected to three different combinations of pressure, temperature and time: 200 MPa at 3 °C for 10 min (lot L), 375 MPa at 38 °C for 20 min (lot H) and atmospheric pressure at 37 °C for 30 min followed by 90 °C for 50 min (lot T), and kept in chilled storage for 20 days. The microorganism content dropped at the outset as pressurizing took effect, the highest microbial content being found in lot L; however as the effect was not lethal, the total load increased over the following days. Microbial load was significantly lower in lot T. During chilled storage, the values of breaking deformation, breaking force and cohesiveness of lot L were higher than those of the other lots, although they did decrease with storage. The heat-induced gel was much harder, had greater water-holding capacity and was considerably more stable than the high-pressure-induced gels. The lightness value was higher in lot H than in the other two lots. In general, changes in protein solubility tended towards the cleavage of strong bonds as a result of microbial action. The electrophoretic profiles evolved differently in each of the lots over the chilled storage period. However, all of them exhibited large numbers of bands of lower molecular mass which could have been the result of degradation. This was particularly evident in lot H. The heat-induced gels exhibited a highly porous ultrastructure, quite different from the high-pressure-induced gels; these had a more compact matrix which expanded as storage progressed.

Suppressive Effect of Phosphatidylcholine on the Thermal Gelation of Alaska Pollack Surimi

Addition of phospholipid (PL) significantly lowered the breaking force and deformation of the thermal gel of Alaska pollack surimi by suppressing the setting, while triglyceride (TG) did not affect the gelation profile. Phosphatidylcholine (PC) was responsible for the inhibitory effect of PL on setting. Neither choline nor phosphorylcholine had such an effect. PL addition did not inhibit the cross-linking reaction of the myosin heavy chain occurring in the setting process at all. It was, therefore, concluded that the amphipathic property of PC was required to inhibit the setting and that noncovalent bonds necessary for network formation in the set gel might be interfered by PL in a liposome-like form. Keywords: Gelation; phosphatidylcholine; pollack; surimi; transglutaminase

Influence of added salt and non-muscle proteins on the rheology and ultrastructure of gels made from minced flesh of sardine ( Sardina pilchardus)

A study of rheological and ultrastructural properties of gels made from sardine was undertaken in order to examine the effects of adding non-muscle proteins (egg white, soy protein, casein and gluten) at different gelling temperatures. The highest values for gel strength, breaking force and breaking deformation were obtained with 2.5% salt content, which produced a more homogeneous gel matrix. Suwari gels containing soy protein exhibited greater gel strength, while for gels cooked at 90 °C the gel strength was highest in those containing egg white and a true three-dimensional network was displayed.

The effect of washing water parameters (pH, hardness and sodium pyrophosphate content) on the water-holding capacity and gelation characteristics of sardine ( Sardina pilchardus ) mince

In order to determine the effect of washing water parameters [pH, hardness and tetrasodium pyrophosphate (TSPP) content] on the water-holding capacity (WHC) and gelation properties of sardine (Sardina pilchardus) mince, two experiments designed by response surface methodology were carried out. The WHC of the mince was maximum when washed in the pH range of 6.5–7.0, with TSPP>1.7 g ⋅ l-1, and CaCO3 between 30 and 60 mg ⋅ l-1. With the exception of breaking deformation and the folding test, where the highest values were obtained at 60 mg ⋅ l-1 CaCO3, the variation of water hardness did not induce any significant changes in the other rheological parameters. The use of relatively high concentrations of TSPP in the leaching water contributed to the achievement of high values of breaking deformation, though beyond 2.5 g ⋅ l-1 a detrimental effect on breaking force was observed, and consequently also on gel strength.

Effect of Measuring Temperature on the Physical Properties of Horse Mackerel Gels.

In order to investigate the difference in the protein network structure among suwari gel, kamaboko gel, and suwari-kamaboko gel, the effect of measuring temperature on their visco-elasticity was examined. These gels were prepared from the same surimi paste of horse mackerel Trachurus japonicus, by setting at 40°C for 1h, by heating at 80°C for 30min, and by heating at 80°C for 30min after setting at 40°C for 1h, respectively. With rising the measuring temperature from 5°C to 40°C, storage modulus and loss modulus obtained by dynamic test, elasticity modulus and viscosity obtained by stress-relaxation test, and compression stress before breakage in a puncture test decreased for all the gels but the breaking force and breaking deformation increased. Furthermore, master curves could be drawn from the time-stress curves recorded by the puncture test for these gels. Based on the above results, the network structure in these gels and its dispersion in them were discussed.

Ultrastructural and rheological changes during the gelation of giant squid (Dosidicus gigas) muscle

The giant squid or dosidicus (Dosidicus gigas) is normally shipped frozen from the coasts of America. During the period prior to freezing-when conditions are not always optimum-and during frozen storage, the functional capacity of the muscle proteins declines, rendering the material useless for certain processes such as conversion to gel. This paper examines the reasons for the lack of a good gel-forming capacity as measured both rheologically (breaking force, breaking deformation and gel strength) and in terms of ultrastructure (scanning microscopy). The study was carried out at four different temperatures known to be critical for fish muscle protein gel formation, and at two salt concentrations. At 35°C the structure was spongier in gels made with 1.5% NaCl, although a true gel was still not formed, as shown by rheological measurements. Above 30°C, the ultrastructure became more cellular, particularly in samples made with 2.5% NaCl, at which concentration gel strength values were higher. However, at neither salt concentration nor at any of the experimental temperatures was the mesh as spongy as in other fish gels reported in the literature. The values of rheological analysis and folding test were correspondingly low.

The use of native triticale in poultry. 3. Use in laying hens

In three trials with a total of 3240 white laying hybrids, 10 to 72% Triticale of the variety "Grado" was used as a substitute for maize and wheat. The feeding of Triticale had no influence on feed consumption, laying performance, feed efficiency, mortality or weight gain. In two of three trials the egg weight was lowered with an increasing amount of Triticale in the diet. After supplementation of 1 or 1.5% sunflower oil to the diets with 50 resp. 72% Triticale the egg weight increased again to the level of the control group. With the exception of one group, there was no correlation between breaking strength and deformation of the eggs. The colour intensity of the egg yolk was decreased with increasing amounts of Triticale in the diet. It can be concluded, that laying hen feed supplemented with oil may contain up to 50% Triticale, but in non-supplemented diets the highest amount of Triticale should be only 20% because of the risk of linoleic acid shortage.

Mechanism for the Gelation of Unheated Surimi by Vinegar Curing

The mechanism for the formation of vinegar-cured, unheated surimi-gel, so called shime-kamaboko in Japan, from Alaska pollack frozen surimi was investigated. In the SDS-PAGE pattern, a band due to the myosin heavy chain disappeared after dialyzing a sol of the salted fish flesh, shio-surimi, against Walpole buffer (pH 0.5–6.5). The breaking force and deformation of shime-kamaboko were maximized at around pH 4.0, but remained constant in the pH range of 1.0–4.2 if the muscle proteins of the surimi were succinylated. These values were increased by adding salt, but decreased by adding urea or guanidine-HCl. The fluorescence intensity of shio-surimi measured in the presence of ANS-Na was scarcely affected by reducing the pH value.

Symmetry breaking in thermally activated NH 4 rotation studied by NMR level crossing spectroscopy

Hindered ammonium ions and level crossing NMR are used to study thermally activated rotation. Hindered rotation is a quantum trajectory occurring with a symmetry breaking deformation of the ion which creates rotational coordinates with an associated vector potential. The coordinates label the protons and modify the proton spin symmetry rules which apply to the wavefunctions of an ion in a static hindering potential. The degeneracy of the Kramers doublets is lifted and twelve orientations of the tetrahedron are identified instead of the six distinguished by the proton spin in the static case. Level crossing NMR spectra of ammonium persulphate between 4 and 20 K demonstrate the splitting through the large difference in the thermal broadening of transitions involving doublet and singlet states. New discrete structure which appears in the tunnelling spectrum with increasing temperature may be due to frequency modulation due to precession of the rotation axis about the crystal field symmetry axis. The symmetry breaking makes the quantum and classical descriptions of hindered rotation compatible.

Several technical factors affecting the texture of reconstructed sardine meat.

Reconstructed sardine meat was prepared from a mixture of sardine mince and sodium alginate by the aid of dialysis with respect to CaCl2 solution. A soft consistency was preferred to match with Western style dishes. The effect of NaCl or MgCl2 included in the CaCl2 solution and the effect of enzyme treatment of sardine mince were investigated to obtain a soft consistency. When the NaCI concentration was more than 0.1M, the jelly strength became remarkably smaller than that at 0.00M NaCl. As the NaCl concentration increased, breaking deformation increased at the early stage of dialysis. A suitable soft consistency was obtained by 0.1M NaCl and 48h dialysis. The jelly strength at 0.004M MgCl2 was remarkably smaller than that at 0.000M MgCl2. As the MgCl2 concentration increased, breaking deformation increased at the early stage of dialysis, but decreased at the late stage. A moderate consistency was obtained by 0.016M MgCl2 and 48h dialysis but was unacceptable due to other attributes. As the enzyme concentration increased, the jelly strength increased at the early stage of dialysis, but decreased at the late stage and as the enzyme concentration increased, breaking deformation increased, and maximum breaking deformation was observed when enzyme concentration was 0.5%. When the time for enzyme treatment was increased, the jelly strength and breaking deformation increased once and then decreased, and the maximum jelly strength and breaking deformation were observed when the time for enzyme treatment was 30min. A suitable soft consistency was obtained by enzyme treatment for 30min at 0.5% enzyme and 48h dialysis.

Statistical aspects of the plastic fracture of a filled high-density polyethylene

The study object was a statistical model of the localized plastic fracture of a filled polymer. With HDPE as an example we studied the extent to which macroscopic breaking deformations of the material are influenced by the filler content and by the uniformity of its distribution in the matrix. Fluctuations in the volume content of filler in the material due to the technology of the composite preparation have a marked effect on the plastic properties of the material. The scale effects of the localized fracture were investigated.

Depression of elasticity of kamaboko induced by pregelatinized starch.

The reason for the depression of the elasticity of kamaboko upon the addition of pregelatinized starch was investigated. The breaking force and breaking deformation of the kamaboko from Alaska pollack frozen surimi were decreased and its expressible water was increased by increasing the amount of the pregelatinized corn, potato, and tapioca starches added and this was especially remarkable for the latter two starches. Such the depression in the elasticity was accelerated by the previous soaking of them in water immediately before their addition, but prevented by retarding their addition to the surimi during its grinding. The pregelatinized starch absorbed more water than the raw one during heating within 3% sodium chloride and its mechanical strength was decreased. Furthermore, it was observed that the pregelatinized starch existed as granules within the kamaboko. From the results, it was proposed that the depression of the elasticity of the kamaboko upon the addition of the pregelatinized starch is due to the reduction of its mechanical strength upon the marked absorption of water during the kamaboko processing.

Textural characterization of new fish product with plastic consistency.

In the trial to develop various methods for utilization of minced fish, a new fish product with plastic consistency was manufactured from enzyme-treated minced fish and palm oil. By the sensory evaluation of texture, our new fish product was evaluated to be fairly similar to processed cheese. The quality of our product depended mainly on its texture. Therefore the texture of our product was investigated rheologically. In the creep and recovery measurements, our product appeared to have plastic (non-recoverable) properties in instantaneous and retarded parts while processed cheese appeared to have plastic property only in instantaneous part. In the stress relaxation measurement, the relaxation modulus of our product decreased very quickly. These results mean that the structure of our product was easily broken down during the measurements. In the plunger penetration test of our product, the large drop of force after the first peak of the force vs. deformation curve, was not observed. Though this curve was steep at the origin and the instantaneous modulus was large in our product, the jelly strength and the breaking deformation were small. These properties of our product were similar to those of processed cheese, and quite different from those of kamaboko. However, the structural breakdown was more remarkable in our product than in the processed cheese, in creep and stress relaxation measurements and also in plunger penetration test.