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The objectives of this study were to examine and develop a model to describe the survival of Listeria monocytogenes in salmon as affected by salt, smoke compound (phenol), and smoking process temperature. Cooked minced salmon containing selected levels of salt (0%, 2%, 4%, and 6%) and smoke compound (0, 5, 10, and 15 ppm phenol) were inoculated with a 6-strain mixture of L. monocytogenes to an inoculum level of 6.0 log10 CFU/g. The populations of L. monocytogenes in salmon during processing at 40, 45, 50, and 55 °C that simulated cold- and hot-smoking process temperatures were determined, and the effects of salt, phenol, and temperature on the survival of L. monocytogenes in salmon were analyzed and described with an exponential regression. At 40 °C, the populations of L. monocytogenes in salmon decreased slightly with inactivation rates of <0.01 log10 CFU/h, and at 45, 50, and 55 °C, the inactivation rates were 0.01 to 0.03, 0.15 to 0.30, and 2.8 to 3.5 log10 CFU/h, respectively. An exponential regression model was developed and was shown to closely describe the inactivation rates of L. monocytogenes as affected by the individual and combined effects of salt, phenol, and smoking process temperature. Temperature was the main effector in inactivating L. monocytogenes while salt and phenol contributed additional inactivation effects. This study demonstrated the inactivation effects of salt, smoke compound, and temperature on L. monocytogenes in salmon under a smoking process. The data and model can be used by manufacturers of smoked seafood to select concentrations of salt and smoke compound and alternative smoking process temperatures at 40 to 55 °C to minimize the presence of L. monocytogenes in smoked seafood. [ABSTRACT FROM AUTHOR]

The characteristic flavors, with the exception of umami, of dried bonito stock not only enhanced saltiness but also improved palatability, namely the acceptability, of salt-reduced foods. However, the respective effects of odorants and tastants of dried bonito stock on palatability have yet to be fully explained. Thus, the effect of dried bonito stock aroma on saltiness enhancement and palatability improvement in salt-reduced food was evaluated by sensory assessment. Probit analysis indicated that aromas of the stocks, arabushi and karebushi, did not affect the intensity of saltiness. However, the test sample with aromas of dried bonito stocks was significantly more palatable than the reference sample. The effects of the taste of dried bonito stock were also evaluated. Probit analysis indicated that enhanced saltiness was not observed in the MSG solution but was observed with the dried bonito stocks, when controlled for aroma. These results suggest that saltiness enhancement by dried bonito stock was caused by the characteristic taste (excluding umami) of dried bonito stock, while its characteristic aroma and umami were involved in preventing the loss of palatability of a low-salt diet. Moreover, it was found that using a combination of karebushi and dried kelp, as material for making stock, could contribute effectively to the preparation of palatable salt-reduced foods in Japan. Invention of new seasonings for improving the palatability of salt-reduced foods could exploit these findings. [ABSTRACT FROM AUTHOR]

In recent years, health concerns related to salt/sodium chloride consumption have caused an increased demand for salt-reduced foods. Consequently, sodium chloride (NaCl) reduction in foods has become an important challenge. The more so, since a decrease in NaCl content is often reported to be associated with a decrease in consumer acceptance. The objective of the present study was to investigate whether or not it would be possible to reduce the NaCl content in standard Western European foods by replacing it with naturally brewed soy sauce. Three types of foods were investigated: salad dressing ( n = 56), soup ( n = 52), and stir-fried pork ( n = 57). In the 1st step, an exchange rate (ER) by which NaCl can be replaced with soy sauce without a significant change in the overall taste intensity was established per product type, by means of alternative forced choice tests. In the 2nd step, the same consumers evaluated 5 samples per product type with varying NaCl and/or soy sauce content on pleasantness and several sensory attributes. The results showed that it was possible to achieve a NaCl reduction in the tested foods of, respectively, 50%, 17%, and 29% without leading to significant losses in either overall taste intensity or product pleasantness. These results suggest that it is possible to replace NaCl in foods with naturally brewed soy sauce without lowering the overall taste intensity and to reduce the total NaCl content in these foods without decreasing their consumer acceptance. PRACTICAL APPLICATION: Health concerns related to salt consumption cause an increased demand for salt-reduced foods. Consequently, the development of foods with reduced salt content without decreasing the consumer acceptance is an important challenge for the food industry. A new possible salt reduction approach is described in the present article: The replacement of salt with naturally brewed soy sauce. [ABSTRACT FROM AUTHOR]

A model system consisting of ground farmed cod muscle (80%, w/w) and added brine (20%, w/w) with different content and combinations of salt (0% and 3% in brine) and phosphorus compounds (mono-, di-, tri- and hexametaphosphates; 0% and 3% in brine) was used to simulate industrial brining of muscle foods. Individual phosphorus component concentrations and breakdown as function of time (0, 23 h) were analyzed using 31P-NMR spectroscopy. The effects of salt and phosphate on water holding capacity (WHC) were measured at similar sampling times, and interrelations between phosphorous components determined by NMR and WHC were established. Addition of salt led to a significant increase (+18%) in WHC, and the combined effect of salt and phosphates was even more pronounced (+29%). The positive effect of triphosphate and salt on WHC was also seen after cooking (+36% in raw and +41% in cooked cod muscle, relative to control), although NMR analysis showed a rapid breakdown of di- and triphosphates. [ABSTRACT FROM AUTHOR]

Computed X-ray tomography (CT) was used to determine NaCl, water, and protein levels in dried salted cod. Cod fillets were salted and dried, and CT was conducted several times during the process. Also, homogenized cod samples with a chemical composition covering the typical composition of cod during salting and drying were produced, and CT scanned. Chemical composition of fillet and model samples was predicted from CT images acquired at 80, 110, and 130 kV. The best average prediction errors (RMSECV) obtained for homogenized samples were 0.6% NaCl, 1.3% water, and 1.5% protein; all explained variances were R2= 0.99 or above. The best RMSECVs and explained variances for cod fillet samples were 0.9% NaCl ( R2= 0.96), 0.8% water ( R2= 0.99), and 1.4% protein ( R2= 0.79). Combining CT values from 2 or 3 voltages gave the best predictions except when predicting salt in cod fillet, where 1 voltage was sufficient. [ABSTRACT FROM AUTHOR]

USDA Select striploins (IMPS 180; n= 24) were cut into thirds (anterior, medial, and posterior) and assigned to 1 of 8 treatments utilizing a randomized incomplete block design. Treatments included (1) control (C); (2) 1.5% conjugated linoleic acid (conjugated linoleic acid = CLA) (CGA); (3) 0.4% sodium tripolyphosphate (PHO); (4) 0.5% salt (SAL); (5) 0.4% sodium tripolyphosphate, 0.5% salt (SPH); (6) 0.4% sodium tripolyphosphate, 1.5% CLA (PCL); (7) 0.5% salt, 1.5% CLA (SCL); and (8) 0.4% sodium tripolyphosphate, 0.5% salt, 1.5% CLA (SPC). Treatments were injected with solutions to 110% (10% pump) of their original weight. Treatments with CLA had higher ( P < 0.05) marbling scores than treatments that did not. Not including SAL, treatments with salt, or phosphate or a combination of the two had higher tenderness values when sampled by panelists. Fresh steaks with inclusion of CLA had greater amounts ( P < 0.05) of the CLA isomers than steaks not having CLA. Cooked steaks having CLA also had greater amounts ( P < 0.05) of CLA, except for SCL, which were not different ( P > 0.05) from the non-CLA treatments. Day was a significant source of variability for a*, b*, and saturation index. Treatment × day interactions were significant ( P < 0.05) for hue angle and L* values. These data suggest that inclusion of CLA can increase amounts of CLA isomers without major deleterious effects to instrumental, physical, and quality characteristics of beef striploin steaks. [ABSTRACT FROM AUTHOR]

Functional properties of pasteurized process cheese (PPC) made with different types of emulsifying salts (ES) (2%, wt/wt) were investigated as a function of different pH values (from 5.3 to approximately 5.9). The ES investigated were trisodium citrate (TSC), disodium phosphate (DSP), sodium hexametaphosphate (SHMP), and tetrasodium pyrophosphate (TSPP). Meltability and textural properties were determined using UW-MeltProfiler and uniaxial compression, respectively. All PPC samples exhibited an increase in degree of flow (DOF) determined at 45 °C when the pH was increased from 5.3 to 5.6, presumably reflecting greater Ca binding by the ES, increased charge repulsion and therefore greater casein dispersion. When the pH of PPC was increased from 5.6 to approximately 5.9, 2 types of ES (DSP and SHMP) exhibited no further increase in DOF at 45 °C; while DOF increased in 1 type of PPC (made with TSC) but decreased in another (made with TSPP). TSPP is able to form crosslinks with casein especially in the vicinity of pH 6, which likely restricted melt; in contrast TSC does not crosslink caseins and the increase in pH helped cause greater casein dispersion. Low pH samples (5.3) were not significantly harder than higher pH samples for all ES types but exhibited fracture. The PPC with the highest hardness values at pHs 5.3 and 5.6 were made with TSPP and TSC, respectively. The pH-dependent functional behavior of PPC was strongly influenced by the type of ES and its physicochemical properties including its ability to bind Ca, the possible creation of crosslinks with casein and casein dispersion during cooking. [ABSTRACT FROM AUTHOR]

The objectives of the present study were to measure the ideal salt concentration in French-type bread among Argentine consumers in a home-usage-test (HUT) considering income status and salt content of daily bread consumption as covariables, and to compare the ideal salt concentrations measured in a HUT and a central-location test (CLT). For the HUT, 420 consumers each received a sample of bread with a single salt concentration, and for the CLT, 100 consumers each received 7 samples with different salt concentrations. For each sample, consumers responded if they found the bread “not-salty-enough,”“okay,” or “too-salty.” Neither income level nor salt content of daily bread influenced probability of rejection. The optimum sodium concentrations (milligrams per 100 g of bread dry basis) ± 95% confidence limits for the HUT and CLT were 980 ± 74 and 1157 ± 87, respectively. These values are substantially higher than 628, the mean sodium content of the bread sampled from the bakery shops where consumers bought their daily bread. [ABSTRACT FROM AUTHOR]

Salt effect on gelling properties of fish protein isolate (FPI) prepared by acid- and alkali-aided extraction was investigated. Acid- or alkali-extracted FPI formed significantly better gel texture with 0% NaCl than with 3% NaCl. Texture properties of acid- or alkali-extracted FPI decreased as NaCl content increased, especially at 2% to 3% salt. Contrarily, salt significantly promoted texture qualities of conventional surimi gels. The effect was highlighted when they were subjected to low temperature setting. The myofibrillar proteins in FPI were not solubilized when NaCl was added, perhaps due to protein aggregation caused by acid or alkali extraction. FPI solubility, however, was not closely related to their texture properties. Cold setting did not promote texture properties of FPI gels as much as conventional surimi gels. Acid-extracted gels gave the best color properties. [ABSTRACT FROM AUTHOR]

Nutrient-deprived Listeria monocytogenes have increased resistance to processing control measures. Heat-stressed L. monocytogenes cells produce higher counts under anaerobic conditions and SigB reportedly contributes to the survival of environmentally stressed Gram-positive bacteria. In this study, a wild type (wt) strain, L. monocytogenes 10403S, and a Δ sigB mutant, FSLA1-254, were stressed by starvation in phosphate buffered saline coupled with exposure to chemicals with/without oxygen. In the absence of chemicals, the mutant survived starvation almost as well as the wt, suggesting that the starvation survival response (SSR) in L. monocytogenes was SigB-independent. Conversely, in the presence of chemical stresses the SSR results differed depending on the chemical used. In the presence of sodium chloride (SC), both strains were able to express an SSR under aerobic conditions but not under anaerobic conditions. However, in the presence of sodium propionate (SP), the mutant yielded counts that were 2 log CFU/mL lower than the controls and their aerobic counterparts. In the presence of sodium lactate (SL), the mutant yielded counts that were approximately 3 log CFU/mL lower than the wt under anaerobic conditions. Thus, for the chemical stress produced by SC, the SSR appeared to be SigB-independent. The SSR of L. monocytogenes appeared to be SigB-dependent following exposure to SP or SL under anaerobic conditions. Following exposure to sodium diacetate or lauric acid, both strains were unable to express an SSR. No detectable CFUs were observed after 14 to 21 d under either aerobic or anaerobic incubation. Therefore, these 2 chemicals could be used in biocidal formulations against L. monocytogenes cells under aerobic or anaerobic conditions. [ABSTRACT FROM AUTHOR]

Coconut milk (16% to 17% fat, 1.8% to 2% protein) was extracted from coconut ( Cocos nucifera L.) endosperm and diluted in buffer to produce natural oil-in-water emulsions (10 wt% oil). The effect of pH (3 to 7) and NaCl (0 to 200 mM) on the properties and stability, namely, mean particle size, ζ-potential, viscosity, microstructure, and creaming stability, of the natural coconut milk emulsions was investigated. At pH values close to the isoelectric point (IEP) of the coconut proteins (pH 3.5 to 4) and in the absence of NaCl, coconut milk flocculated, but did not coalesce. Flocculation corresponded to low surface charges and was accompanied by an increase in emulsion viscosity. Adding up to 200 mM NaCl to those flocculated emulsions did not change the apparent degree of flocculation. Coconut milk emulsion at pH 6 was negatively charged and not flocculated. Upon addition of salt, the ζ-potential decreased from –16 to –6 mV (at 200 mM NaCl) but this was not sufficient to induce flocculation in coconut milk emulsions. At low pH (< IEP), the positively charged droplets of coconut milk emulsions only flocculated when the NaCl concentration exceeded 50 mM, as the ζ-potential approached zero. [ABSTRACT FROM AUTHOR]

There is a pressing need for the development of ways of preparing palatable salt-reduced foods to reduce the salt intake of the Japanese population. The salt-reducing effect of the characteristic flavors other than umami of dried bonito stock, which is widely used in everyday Japanese food, was examined by sensory evaluation. In the 1st sensory evaluation, the effect was evaluated in a model solution. The saltiness of 0.80% NaCl solution was equivalent to that of 0.12% monosodium glutamate (MSG) solution containing 0.81% NaCl and dried bonito stock containing 0.68% NaCl. Saltiness enhancement could not be found when MSG solution was used, but was found with 6% dried bonito stock. The 2nd evaluation examined whether the effect was valid for 2 everyday Japanese foods—traditional Japanese clear soup ( sumashi-jiru) and steamed egg custard ( tamagodoufu). Although enhancement of saltiness by dried bonito stock could not be clearly demonstrated in the soup, a change in NaCl concentration within 15% did not affect the palatability of the soup. However, dried bonito stock not only enhanced the saltiness but also improved the palatability of steamed egg custard. These findings are expected to be useful for improving the palatability of salt-reduced food. [ABSTRACT FROM AUTHOR]

This study was aimed at developing value-added low sodium chloride (NaCl), phosphate-free restructured patties using minced channel catfish ( Ictalurus punctatus) belly flap meat. The effect of microbial transglutaminase (MTGase) and nonmeat proteins (isolated soy protein, ISP, and whey protein concentrate, WPC; 1.7%, respectively) alone and in combination were evaluated to improve cooking yield and textural properties in patties with reduced NaCl and no phosphate. The concentration effect of MTGase (0.05% to 0.7%) was also studied. The addition of MTGase increased textural properties such as binding strength, hardness, cohesiveness, chewiness, and springiness, but decreased cooking yield of the patties ( P < 0.05). Isolated soy protein increased cooking yield ( P < 0.05), but did not affect textural properties. Inclusion of WPC did not increase cooking yield or impact textural properties of patties. The combination of MTGase and ISP significantly increased both the cooking yield and textural properties of patties. As the concentration of MTGase increased at constant ISP, the textural properties of cooked patties significantly increased, but cooking yield decreased ( P < 0.05). In conclusion, we suggest that the combination of 0.05% to 0.1% of MTGase with 1.7% ISP is optimal for development of a low NaCl, phosphate-free patty using minced catfish belly flap meat. [ABSTRACT FROM AUTHOR]

We examined the effects of NaCl and glucose on cold-set ovalbumin gelation. Cold-set gels were prepared by adding glucono-δ-lactone (GDL) to a 2% heated ovalbumin solution. For the gel prepared from ovalbumin heat-denatured with NaCl and glucose, the gel with 10 mM NaCl was most transparent and had high gel strength. Its maximum complex shear modulus ( G*) and turbidity were 2.5 times greater and 3 times lower, respectively, than those of the gel without NaCl. The turbidity of the gel with the higher NaCl content increased steeply after the addition of GDL and did not change during the experimental period. The maximum G* of the gel exhibited positive correlations with the molar mass, radius, and surface hydrophobicity of soluble aggregates and the NaCl content, but the turbidity exhibited negative correlations with these factors. The presence of glucose did not significantly affect the turbidity or rheological properties of the gel. For the gel prepared by adding NaCl and glucose with GDL, the presence of glucose did not affect the turbidity, but the maximum G* decreased in inverse proportion to the glucose content. The turbidity of the gel with higher NaCl content (≥ 50 mM) was the greatest among all samples, and the increased turbidity was maintained throughout the measurements. The gels with 50 and 100 mM NaCl exhibited thixotropy during shearing at a constant shear rate. Therefore, the presence of NaCl and glucose during cold gelation could facilitate the preparation of cold-set gels having various properties for food applications. [ABSTRACT FROM AUTHOR]

The molecular characteristics of ovalbumin aggregates formed by heating with NaCl and glucose were investigated with a multi-angle laser light scattering system. The presence of NaCl and glucose affected the formation and molecular structure of the aggregates. Specifically, glucose increased the denaturation temperature of ovalbumin due to thermal stabilization of the native state of ovalbumin, regardless of the content of added NaCl. The surface hydrophobicity of the aggregates was increased by the addition of NaCl, which induced the denaturation of ovalbumin at a lower temperature. Aggregates with a larger weight-average molar mass ( Mw) and root mean square radius ( Rg) formed from heat-denatured ovalbumin with NaCl and glucose. The presence of NaCl during heat denaturation caused the formation of aggregates with a larger Mw (1.9 × 105 and 3.5 × 106 g/mol for 0 and 10 mM NaCl, respectively) and Rg (14.8 and 80.4 nm for 0 and 10 mM NaCl, respectively). Over a certain amount of NaCl, the addition of more glucose resulted in the formation of more aggregates with greater Mw and Rg values. In sum, the thermostability of ovalbumin was affected primarily by glucose, but the molecular characteristics of the soluble aggregates formed by heat denaturation varied primarily with NaCl content. [ABSTRACT FROM AUTHOR]

BSTRACT: Thermal texture degradation of carrots was studied at a temperature of 100 °C in aqueous solutions containing sodium chloride, citric acid, ascorbic acid, and ethylenediaminetetraacetic acid (EDTA) at different concentrations. To enhance the texture of the final product, the carrot samples were pretreated at 65 °C for 30 min in an aqueous calcium chloride solution (5 g/L). For all case studies considered, the pH of the solutions was adjusted to pH = 6.0. In parallel, both the changes in degree of esterification (DE) and the progress of the β-elimination reaction of carrot pectin under the same conditions were investigated. The kinetic parameters for texture degradation (rate constant kt and final texture value [TP∞/TP0]) were estimated using a fractional conversion model. The results indicate that both the rate constant for texture degradation ( kt) and the rate constant for the β-elimination reaction ( kb) increased with increasing additive concentration, while the final texture values (TP∞/TP0) and DE decreased with increasing additive concentration in all systems studied. A high correlation was observed between the relative rate constant for texture degradation and the relative rate constant for the β-elimination reaction on the one hand, and the relative final texture value and the relative rate constant for the β-elimination reaction on the other hand, suggesting that the influence of the solutes on texture degradation can be explained by their influence on the β-elimination reaction. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the optimization of salt concentration in the salting-in step and the effects on β-conglycinin yield, purity and subunit distribution. Some changes were made for the control fractionation procedure of the study. Results of the study showed an inverse correlation between yields of protein and solids of the intermediate fraction and salt concentration. It also found that low yields for β-conglycinin-rich fraction at low ionic strengths.

BSTRACT The effect of various pre-drying treatments on the subsequent quality of sun-dried tomatoes was evaluated by determining moisture, color, rehydration ratio, mold, yeast, sulfur dioxide, and/or salt content. The 4 pre-drying treatments under investigation were (1) steam blanching or (2) boiling brine blanching, followed by gas sulfuring and (3) dipping in either salt (0%, 10%, 15%, 20%) or (4) sodium metabisulfite (0%, 4%, 6%, 8%) for 0, 2.5, 5.0, and 7.5 min. Neither blanching pretreatment improved the quality of the dried product. Salt dipping resulted in significant differences in rehydration ratio, yeast, and salt. The most effective salt pretreatment conditions were a 10% or 15% salt dip for 5 min. Sodium metabisulfite dipping caused significant differences in rehydration ratio, yeast, color, and sulfur dioxide. Dipping tomatoes in 6% or 8% sodium metabisulfite for 5 min before drying established the best color. The 9 pretreatments studied were also evaluated for storage stability at 25 °C and 30% to 34% relative humidity for 3 mo. [ABSTRACT FROM AUTHOR]

BSTRACT: To reduce the microbial load of ready-to-use desalted cod, 2 different concentrations of sodium chloride (3.13% and 5.78% in water phase), potassium sorbate (0.14% and 0.20% in water phase), and citric acid (pH 6.10 and 5.77), with 2 kinds of packaging procedures (air or vacuum), have been used. The vacuum packaging was effective only in the samples with 3.13% salt after 28 d of storage, whereas no important differences between both packaging procedures were observed in samples with 5.78% salt. This last salt level only limited the Pseudomonas growth, however it was necessary to combine this salt concentration with potassium sorbate plus citric acid to inhibit mesophilic, psychrotrophic, and molds and yeasts. [ABSTRACT FROM AUTHOR]

BSTRACT: Increased survival of freeze-dried cells of Lactobacillus bulgaricus was observed when the drying medium was supplemented with sucrose; however, the magnitude of such protection was dependent on the growth medium used. Supplementing the growth medium with NaCl markedly increased survival of dried cells, and only a small effect was exerted by the composition of the drying medium or prior to starvation of cells. The D57 values of Lactobacillus bulgaricus cells grown in MRS were about half of those of cells grown in MRS supplemented with sucrose, with sucrose plus NaCl, or with NaCl. [ABSTRACT FROM AUTHOR]

The article presents information on a study which evaluated the stability of local salt dual fortified with iodine and 19 iron compounds in Morocco and Côte d'Ivoire. A review of the related literature on the fortification of salt is given. The color and iodine content were quantified following storage for one, two, four and six months. Findings showed that encapsulation did not protect against adverse sensory changes and iodine losses.

The article presents information on a study which identified how brine components, namely, salt and sodium tripolyphosphate (STPP) might influence the immunological quantification of lactate dehydrogenase isozyme 5 (LDH5) in preparations of beef Semimembranosus muscle following heating to particular end point temperatures (EPT). The likelihood that EPT could be identified accurately at 1°C intervals by quantifying LDH5 levels was also determined.

The extractability of proteins by NaCl, KCl, and LiCl as affected by different ionic strengths and pH was compared to determine the best protein extractant. The individual proteins in the extracts were identified by electrophoresis. The optimum ionic strength (IS) at pH 7.0 for the protein extractability (PE) of NaCl, KCl, and LiCl were 0.8, 0.9, and 1.0, respectively. The PE of NaCl and KCl declined as pH changed from 6.0 to 8.0, whereas an opposite effect was observed for the LiCl. The NaCl had the highest PE, followed by LiCl and KCl. The maximum number of proteins (15 bands) was found at the optimum IS of each salt. However, the resolution and clarity of the protein bands were better in the NaCl extracts. [ABSTRACT FROM AUTHOR]

BSTRACT: Artificial neural networks (ANN) was evaluated and compared with Response Surface Model (RSM) results using growth response data for E.coli O157:H7 as affected by 5 variables: pH, sodium chloride, and nitrite concentrations, temperature, and aerobic/anaerobic conditions. The best ANN obtained, where the 2 kinetic parameters, growth rate and lag-time, were estimated jointly, contained 17 parameters and displayed a slightly lower Standard Error of Prediction (% SEP) than those obtained with RSM. Mathematical lag-time validation with additional data gave a lower %SEP for ANN (18%) than for RSM (27%), although growth-rate values were the same (22%). ANN thus should provide the innovative possibility of obtaining a single predictive model for the estimation of several kinetic parameters. [ABSTRACT FROM AUTHOR]

BSTRACT: In a case study on green peas, nonuniformity in microbial lethality and nonuniformity in quality retention (color) in retort processing was investigated by combining nonuniformity in the product (heat penetration data) and nonuniformity in the retort (heat distribution data) through simulations. The fractional conversion model was applied to model the color degradation of peas. The temperature dependence of color degradation decimal reduction times could be described by TDT (Thermal Death Time) equations with a z-value of 47.5 ± 5.9 °C. Heat penetration trials were conducted on peas in brine to determine the variability in heating parameters. A theoretical optimization procedure was carried out, and an experimental verification of the calculated results was conducted. [ABSTRACT FROM AUTHOR]

BSTRACT: Arctic char hatched at 6.5 and 9.5 °C and later divided into large, medium, and small size groups were assigned to processing (1) without handling stress, (2) immediately after handling stress, (3) at 24 h after handling stress, and (4) at 48 h after handling stress. Stress reduced gut weight and muscle a* value, increased muscle L* for the 9.5 °C group, decreased muscle L* for the 6.5 °C group, and increased fillet weight loss after brining. Fillets from the stressed, 9.5 °C group absorbed more brine, increasing salt and ash content of smoked products. A 24-h stress recovery decreased total- and water-phase salt. Fish hatched at 9.5 °C appeared to be more sensitive to handling stress than fish hatched at 6.5 °C. A 48-h stress recovery increased gut weight and enhanced muscle L*. [ABSTRACT FROM AUTHOR]

BSTRACT: Citrus and jelly fig achene pectinesterase (PE) (1 U/mL) activity was remarkably inhibited by PE inhibitor (PEI) (2 mg/mL) from jelly fig ( Ficus awkeotsang Makino) achenes, in the absence or presence of 0- to 500-mM salts or 0 to 30% of sugars. Changes in temperature (20 to 40 °C) apparently decreased the activity of citrus PE in PE-PEI reaction mixture. Enzyme-activity curves for jelly fig PE alone and for that in combination with PEI were parallel. Activity of crude PEs (1 U/mL) from tomato, apple, asparagus, and guava was reduced remarkably. Cloud loss of fresh tomato juice, apple juice, and papaya juice was greatly inhibited by PEI (1 mg/mL) during 12-wk storage. [ABSTRACT FROM AUTHOR]

BSTRACT: Salt and moisture contents in cold-smoked salmon were determined using short-wavelength near-infrared (SW-NIR) reflectance spectroscopy (600 to 1100 nm). Partial least square (PLS) regression models yielded the best results among 3 linear regression methods tested. Back-propagation neural networks (BPNN) exhibited a somewhat better capability to model salt and moisture concentrations (Salt: R2= 0.824, RMS = 0.55; Moisture: R2= 0.946, RMS = 2.44) than PLS (Salt: R2= 0.775, RMS = 0.63; Moisture: R2= 0.936, RMS = 2.65). Selection of samples from different axial locations on a fish did not affect the prediction error for salt or WPS but affected the prediction error for moisture. [ABSTRACT FROM AUTHOR]

Frozen rainbow trout fillets were brined in 8.7 or 17.4% sodium chloride solutions for various periods. Brine uptake, brined and cooked pH, cook yield, shear force, total and water-phase salt content, and brined and cooked proximate composition were determined. Fish mince was used for texture (hardness and cohesiveness) and protein solubility (total soluble and myofibrillar proteins) evaluations. Increasing the brine concentration increased fillet weight loss after brining, cook yield, water-phase salt content, shear force, brined fat, brined and cooked ash, brined pH, and brined and cooked moisture. [ABSTRACT FROM AUTHOR]

The formation of histamine in fish sauce made from Stolephorus sp. was studied. In the first experiment, fish were iced on board and mixed with salt at the factory, while in the second experiment fish were mixed with salt on board collection vessels. Eight batches were fermented for 12 mo. Histamine levels increased during fermentation to 22 to 159 and 589 to 686 ppm in the first and second experiments respectively. Good correlation between histamine levels in raw material and final products was found. It was concluded that histamine was formed both in the raw material and during fermentation. It was speculated that histidine decarboxylase enzymes formed prior to fermentation produced histamine during fermentation. [ABSTRACT FROM AUTHOR]

Variation in dielectric properties of aqueous solutions with different concentrations and ratios of NaCl, D-sorbitol, and sucrose were investigated at 21 °C using the open-ended coaxial probe technique at 2450 MHz. Several equations to estimate dielectric properties of mixed or pure solutions were formulated. The equations were tested with other concentrations of solutions and surimi as a food sample containing the solutes. The correlation between the new measured dielectric properties and the calculated values were analyzed using a General Linear Model. The resultant prediction equations are suitable for pure and mixed aqueous solutions of (0 to 6%) NaCl, (0 to 18%) D-sorbitol and (0 to 60%) sucrose. For surimi, only loss factor was successfully predicted. [ABSTRACT FROM AUTHOR]

The article investigates the production of low salted and fermented shrimp by irradiation. Findings showed an increase in volatile basic nitrogen contents as the salt concentration and irradiation dose decreases during fermentation. The researchers observed the effectiveness of combined low salt concentration and gamma irradiation in the processing of low-salted and fermented shrimp based on the results of sensory analysis, total bacterial count and ion concentration (pH).

The article identifies the factors determining yield stress and overrun of whey protein foams. The study investigates the effects of co-solutes including sodium chloride, calcium chloride, lactose and glycine, as well as the relative amounts of βlactoglobulin and α-lactalbumin, and protein hydrolysis on whey protein foam yield stress. The researchers studied the link between yield stress and overrun of whey protein foams.

The article examines the influence of increasing brine concentration in the cod-salting process. The researchers investigated the water-weight changes, sodium chloride (NaCl) concentration in the cod liquid phase, and changes to the texture properties of the salted cod product. They also studied changes in the standard deviation throughout the salting process. Results showed increased cod weight in the case of 20 percent brine concentration and reduced weight at saturated brine level.

The article examines the texture changes during the ripening of Port Salut Argentino cheese for two different sampling zones. The study investigated the relationships between the textural characteristics in cheese and physicochemical factors such as equilibrium moduli, salt concentration, moisture content and maturation indexes. The researchers calculated the compression and stress relaxation rates of the cheese samples.

The article determines the feasibility of using salt and microbial transglutaminase (MTGase) as binding agents in restructured fish products resembling hams from frozen sucrose fish-stabilized paste of silver carp Hypophthalmichthys molitrix. The researchers assayed salt and MTGase. The study evaluated the effects of salt on protein solubility of pastes, mechanical properties, water-holding capacity and sodium dodecyl sulphate-polyacrylamide gel electrophoresis of the cooked product.

BSTRACT The effects of α-tocopherol at 0.03%, sodium tripolyphosphate (STP) at 0.3%, alone and in combination, and STP alone at 0.5% on hexanal and sensory attributes of refrigerated cooked ground turkey or pork, with and without salt (1% NaCl), were studied. For turkey, a combination of α-tocopherol with 0.3% STP was nearly as effective as 0.5% STP. Turkey and meaty flavor of samples from these 2 treatments did not decline; hexanal content and staleness scores remained low throughout storage. Slick mouthfeel and metallic aftertaste were less for turkey with the antioxidant combination than with 0.5% STP. In pork, STP alone at 0.3% adequately prevented oxidative flavor changes. α-Tocopherol, when used with STP, provided no additional effect. [ABSTRACT FROM AUTHOR]

Pectinesterase (PE) (7 U/mL), extracted from ripe and soft banana flesh (RSBF), was prepared with a ratio of 4 parts (1:4) 2% NaCl. PE activity in the 2% NaCl extracted from homogenized RSBF and rubbery banana flesh (RBF) were 7 and 2 U/mL, respectively, during the 16 h PE extraction, suggesting the existence of the PE inhibitor (PEI) in RBF. Crude PEI extracts from RBF and RSBF exhibited about 80% and 17% inhibitory ratios, respectively, on banana PE activity. Crude PEI from RBF, boiled for 30 to 180 min, showed a 79 to 82% inhibitory ratio of banana PE activity. [ABSTRACT FROM AUTHOR]

Microbial transglutaminase (MTGase) forms nondisulfide covalent crosslinks in proteins. Changes in activity of MTGase from Streptoverticillium mobaraense after exposure to pressure (100 to 600 MPa for 10 to 60 min, respectively) were analyzed. MTGase activity increased linearly with enzyme concentration, regardless of pressures in the range examined. The Vmax value was changed by pressure while the Km value was indepenent of pressure. Sodium chloride (0 to 0.86 N) apparently caused MTGase destabilization under pressure. Oscillatory pressurization (400 to 600 MPa, 25 °C, 10 min/cycle, 0 to 5 cycles) resulted in a higher degree of inactivation when pressures were greater than 500 MPa. MTGase maintained 60% of its initial activity even after pressurization at 600 MPa for 60 min, indicating that MTGase was pressure-resistant as compared to other enzymes. [ABSTRACT FROM AUTHOR]

BSTRACT: The effect of the addition of corn flour and salt on the textural properties of a commercial dry-mix batter used as coating in fried, battered squid rings was studied. Although salt-containing formulations had significantly lower viscosity values than the other samples, the batter pickup values were not significantly different. The crispness of the fried, battered squid rings was measured. The peak force of penetration, slope of the curve, and area up to the peak force did not show big differences, except the values for the formulation that contained leavening agent. In this case, the force value was significantly lower than the rest and the penetrometry profile was also different, corresponding to a crispy product. Finally, the influence on crispness of time lapsed after frying was also studied. [ABSTRACT FROM AUTHOR]

Sodium chloride of different shapes (hollow pyramid, crushed flake, cube, and porous cube) and sizes (50-200 mesh) were applied by nonelectrostatic and electrostatic powder coating to popcorn coated with 1.2 to 3.3% soybean off. Electrostatic coating was more efficient than nonelectrostatic in all cases. The smaller the particles, the higher the coating efficiency for both electrostatic and nonelectrostatic coating. Crushed flake and hollow pyramid were more efficient than cube and porous cube shapes. Coating efficiency improved as the oil content increased for nonelectrostatic but not electrostatic coating. Use of electrostatic coating can reduce waste and provide a more efficient coating method by decreasing seasoning or oil needed to reach the target level. [ABSTRACT FROM AUTHOR]

An electrochemical treatment system consisting of a pulsed electrical power supply and an electrical treatment chamber was designed and evaluated for inactivation Listeria monocytogenes in recirculated brine for chilling processed bacons. The brine was tested under different currents and temperatures. An average D-value of 1.61 min in the storage tank could be achieved at 7 mA/cm3 current with the fresh brine (t = 0 h). For the spent brine (t = 20 h), the D-value was 2.5 min in the treatment chamber at 35 mA/cm3. The average D-values in the treatment chamber were approximately 2.5 min at all three temperatures (4, 0, -8 8C) at 35 mA/cm3. [ABSTRACT FROM AUTHOR]

The speed of sound and the acoustic reflection coefficient of sucrose (0 to 60 wt%), glycerol (0 to 50 wt%), sodium chloride (0 to 27 wt%) solutions and tomato ketchup (0 to 100 wt%) dispersions were measured using a modified pulse-echo technique (2.25 MHz transducer, 20 °C). The density of all solutions is measured using a vibrating tube densitometer. All measured parameters are linear functions of concentration. Ultrasonic reflectance can provide equally precise measurements of concentration as conventional ultrasonic velocity measurements. For all samples except concentrated ketchup (> 50 wt%), measured reflectance is demonstrated to be a function of ultrasonic velocity and density. [ABSTRACT FROM AUTHOR]

Effect of salt content, grinder pore size, and mixing temperature on structure of sausage meat were investigated after 1 and 4 d. Protein solubility, texture characteristics and muscle ultrastructure were measured. Cellular structure is conserved when salt amount is under 0.3% for all temperatures and grinder pore sizes, or when salt amount is of 0.8% for a temperature higher than 6 °C or a grinding size of 10 mm. Cellular structure is modified when salt amount is above 1.3% whatever the temperature and grinding size, or when salt amount is of 0.8% for a temperature below 6 °C or a grinding size of 1.5 mm. The use of statistical tools permitted to distinguish modified meat from intact preparations. [ABSTRACT FROM AUTHOR]

The combined effect of salt, acetic acid, and pasteurization temperature on the retention of carotenoids in canned pickled carrots and green jalapeño peppers was studied by a central composite design. The results were analyzed by response surface methodology. The carotenoid standards were obtained by open column chromatography and the quantitation was done by HPLC. Only the main carotenoids were quantified: α- and β-carotene in carrots and α-, β-carotene, lutein, and violaxanthin in peppers. After analyzing the experimental results and the restrictions of the Mexican Regulations, 2% NaCl and 2% acetic acid concentrations were recommended. The optimal pasteurization conditions were 70 °C/12.45 min for carrots and 83 °C/5.2 min for peppers. [ABSTRACT FROM AUTHOR]

The influence of inoculum size on the growth kinetics of Clostridium botulinum 56A and percentage of growth-positive samples was studied in a complete factorial design with factors of inoculum size (1, 100, or 10,000 spores), pH, and sodium-chloride concentration. Growth was followed hourly as change in A620. Polynomial regression was used to analyze the data. The time-to-detection and percent growth-positive samples were significantly affected by inoculum size and its quadratic term. When inoculum size increased from 1 to 100 spores/sample, the percent growth-positive samples increased, and the time-to-detection decreased. When the inoculum was 1000 spores/sample or higher, there was little additional effect. Inoculum size might influence results through simple probability or quorum sensing. The maximum growth rate was independent of inoculum levels. [ABSTRACT FROM AUTHOR]

Gelation properties of 4 major protein additives were measured with and without salt during various hydration times. As hydration time increased, stress and strain of beef plasma and egg white gradually decreased regardless of salt. Unsalted whey proteins did not form a gel until the hydration time reached 48 h. Stress values of salted beef plasma with no hydration were significantly high. Soy protein isolate did not form a measurable gel at 9% concentration regardless of the presence of salt under rheological instruments, however its denaturation temperature was detected under DSC. Effect of salt on gel color was more pronounced with whey protein concentrate. [ABSTRACT FROM AUTHOR]

The phase transition temperatures, rheological properties and gel-network characteristics for gelation of κ-carrageenan-salt (NaCl, KCl and CaCl2) solutions and their aged gels were investigated. The effectiveness of increasing gelling and gel-melting temperatures at the salt concentrations examined followed the sequence of K+ > Ca2+ > Na+. This sequence was also true for the gel strength and the melting enthalpy (DH) of the most crosslinked junction zones of aged gels at low salt concentrations. Nonetheless, a different order (Ca++ > K+ and Na+) was found for increasing storage modulus and gelation rate during early-stage gelation, thermal hysteresis and the DH of aged gels in some salt-carrageenan systems. [ABSTRACT FROM AUTHOR]

Channel catfish (Ictalurus punctatus) fillets were treated with hydrogen peroxide (HP), ozonated water (OZ), and ascorbic acid plus salt (AS) or salt solution (BR). All treatments except AS decreased (p ≥ 0.05) Aeromonas, while OZ did not decrease Staphylococcus and Acinetobacter. All treatments except 5 ppm OZ reduced {p ≥ 0.05) initial TCC and PPC. At 0.7% HP, BR, and 10 ppm OZ fillets showed odor spoilage after 8, 10 and 10.5 d, respectively. Fillets treated with HP, OZ, and BR bad higher (p ≥ 0.05) TBARs than control fillets. HP treated fillets had lower (p ≥ 0.05) Hunter 'L' values, while BR treated fillets had higher 'a' and lower (p ≥ 0.05) Hunter 'L', 'b', and SI values than controls. [ABSTRACT FROM AUTHOR]

Two-cycle rapid-visco analysis was performed on the admixture of 1% hsian-tsao leaf gum and 2% wheat starch as a function of salt types and concentrations. The salt concentrations (Cs) studied were 5 to 75 mM for sodium and potassium chloride, and 3.4 to 8.5 mM for calcium and magnesium chloride. The gelling temperature, gelling rate and gel viscosity of the mixed system increased with increasing Cs. In addition, the melting temperature increased, but melting rate and percentage of viscosity loss decreased with increasing Cs. These results indicated the presence of appropriate amount of salts could facilitate and reinforce the formation of junction zones, and provided a more pronounced thermal resistance. [ABSTRACT FROM AUTHOR]