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Polyphenols, a group of secondary metabolites, have well-known relevant effects on human health. During traditional alkalization, this content dramatically lowers. We aimed to evaluate an alternative alkalization method based on extrusion on cocoa functional characteristics. The results showed that the antioxidant capacity and total phenolic values increased as alkali concentration and temperature did, and these values doubled under less extreme conditions. Comparing the functional properties between extruded and traditionally produced powders revealed that catechin, epicatechin and dimers B1 and B2 contents were 43%, 33%, 54% and 34% lower in the extruded samples, respectively. However, this reduction was partially balanced by increased clovamide content up to 50%. Thus the total phenol content and antioxidant capacity of the extruded samples were statistically above those of the commercial one. Hence extrusion alkalization should be considered a new processing alternative to avoid markedly reducing functional properties.

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The effect of different essential oils on the quality and shelf life of fish and seaweed burgers during storage was evaluated. For this purpose, thyme and oregano essential oils were selected at a concentration of 0.05% (v/w). Three types of salmon and seaweed burgers were prepared: without essential oil, burgers with red thyme essential oil (0.05% (v/w)) and burgers with oregano essential oil (0.05% (v/w)), which were vacuum packaged and stored at 4 ℃ for 17 days. Physicochemical and microbiological analyses were carried out periodically throughout storage. The addition of both essential oils did not have any effect on the evolution of the pH, the moisture content or texture parameters. Only the thyme essential oil managed to slightly slow down the increase of total volatile basic nitrogen and trimethylamine nitrogen. The samples with oregano essential oil and especially those with thyme essential oil showed minor oxidation. The salmon and seaweed burgers without essential oils and those which contained oregano essential oil showed a faster increase of mesophilic counts than those which had thyme essential oil, but no noticeable improvement was observed in the shelf life of the burgers with thyme essential oil. To improve the shelf life of the fish and seaweed burgers, it would be necessary to increase the concentration of both essential oils.

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The objective of this work was to study the effect of partial sodium replacement by potassium and packaging conditions on the physicochemical properties of smoked sea bass during cold storage. Sea bass fillets were salted with 100% NaCl (Na samples) or with 50% NaCl-50% KCl (Na:K samples), smoked, packaged under three different conditions (air, vacuum and modified atmosphere) and stored at 4 °C for 42 days. Physicochemical parameters, color and texture were periodically determined in the raw material and in smoked samples during cold storage. The smoking process led to a reduction in moisture, pH and a(w) values, and an increase in water holding capacity, ash and mineral contents. Smoked fish exhibited significant differences in color and texture as compared to fresh fish. The type of packaging had an effect on the pH, water holding capacity and texture. Samples in air exhibited the highest pH values and water holding capacity in these samples gradually decreased during storage. Textural parameters decreased during storage in samples packaged in vacuum and modified atmosphere. The pH of Na samples was initially higher than in Na:K samples, and this difference remained over the rest of the study. The type of salt did not affect the texture or other physicochemical parameters.

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Simultaneous brine thawing/salting process was applied as an alternative to traditional pile salting process using 51 frozen Iberian hams. The effect of this type of salting process on endogenous enzyme activity and sensory quality of Iberian dry-cured hams was analysed. The frozen hams were simultaneously thawed and salted with saturated brine, with and without vacuum pulses, and were compared to hams thawed under refrigeration and traditionally salted. The peptidase and lipase activities were measured at the end of salting and post-salting stages. The activity of cathepsin B+L was reduced in the two brine salted batches while few differences among batches were observed for the other peptidases. Several lipase activities were significantly reduced in the two brine salted batches. The brine thawed processing affected the free fatty acid content at the different stages although the differences were more appreciated at the beginning of the process and no differences were observed at the end. The long ripening time makes these differences negligible and the consumer did not appreciate any differences between the sensory quality of Iberian brine/thawed hams and traditional Iberian thawed pile salted hams.

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The aim of this work was to investigate the effect of pre-cure freezing on the physicochemical, texture and sensory characteristics of raw and dry-cured hams. Both, refrigerated (R) and pre-cure frozen (F) hams showed the same weight losses during the processing. At the green stage F Iberian hams had lower moisture content, higher values of a* and chroma, lower hardness and chewiness and higher adhesiveness and springiness than R ones. However, at the end of the processing R and F Iberian hams only were different in salt content, F hams showing lower values than R ones. Sensory analysis of Iberian dry-cured ham did not show differences in salty taste. Panelist detected a higher fat hardness and lean pastiness in F than in R hams. The overall acceptability for both groups of dry-cured hams was between average and good.

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The influence of sodium chloride on the water holding capacity of meat is well known and described in literature. An increase in water holding capacity is associated with an increase in the swelling pressure in the protein matrix. A novel device was used to measure the swelling pressure during brine salting of muscle cylinders (40×50 mm), in different NaCl brine concentrations (2.5 to 25%) over 6 days at 4°C. Changes in meat composition, weight and height of non-constrained control samples were also measured. The aim of this work was to prove the feasibility of using the developed device in order to quantify the influence of the brine concentration on the magnitude of the swelling pressure. The obtained results indicated the adequacy of the developed device for measuring the meat swelling, while a good correlation of the swelling pressure and the changes in weight and height of the samples was observed.

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The reduction of added sodium chloride in dry-cured ham has been proposed to reduce dietary sodium intake in Mediterranean countries. The effect of substituting sodium chloride with potassium chloride, calcium chloride and magnesium chloride on some physicochemical characteristics of dry-cured ham during processing was evaluated. The results showed that hams salted with a mixture of sodium and potassium chloride registered higher salt concentrations and lower water contents and thus, needed less time to reach the required weight loss at the end of the process. The opposite effect was observed when calcium and magnesium chloride were added to the salt mixture. The observed differences in the texture and colour parameters were mainly due to differences in water and salt content.

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The consumption of cured meat products is not recommended to hypertensive consumers due to its high sodium content. This constitutes an important restriction for this industry, which is becoming more and more important due to the current trends in consumption. The partial replacement of sodium chloride by potassium chloride has been proposed as a possible strategy to reduce the sodium content of this type of products. The aim of this study was to evaluate the effect brought about by partial replacement of sodium chloride with potassium chloride (up to 70%) on physicochemical and microbiological parameters of dry-cured pork loin after the curing and drying process. The results showed that it is possible to obtain low sodium dry-cured loin, up to a 50% replacement of sodium by potassium, with similar physicochemical characteristics to the commercial product with usual amounts of sodium.

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The use of frozen/thawed raw material in the processing of Iberian dry-cured ham has been studied to determine its effect on the sensory quality of the final product. The proteolysis and lipolysis processes were measured by the proteolytic and lipolytic enzyme activities and free amino acids and free fatty acids. The thawed Iberian hams had lower salt contents throughout the process. The use of thawing raw material did not affect the proteolytic enzymes, cathepsins, aminopeptidases and dipeptidylpeptidases, only the activity of dipeptidylpeptidase III was reduced due to thawing. Moreover, there were no differences in the content of free amino acids between fresh and thawed hams during the whole process. However, the use of thawing hams affected the lipolytic activity. The activity of phospholipase and neutral lipase were significantly higher in the thawed hams and also the content of free fatty acids, at all the stages analyzed. Consumer sensory analysis showed thawed Iberian hams had the lowest hardness, probably due to an intense proteolysis. The acceptability of the Iberian hams was similar between fresh and thawed hams.

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Dry-cured ham consumption is restricted by hypertensive consumers due to its high sodium content. This constitutes an important matter for this industry, being relevant due to the current trends in consumption. In order to prevent the problems related to the high sodium intake, one of the possibilities is the total or partial replacement of sodium by other ions, such as potassium, calcium and magnesium. The aim of this study was to characterise the post-salting stage in Spanish cured ham production with the results obtained after salting with low sodium salt content. The results showed that lower sodium hams needed more time of post-salting to reach similar water activity values than those achieved by hams salted with 100% NaCl. Nevertheless, no differences in microbial counts were observed among the studied batches, although a sharp decrease in microbiota was observed when the, post-salting time was prolonged in the lower sodium hams.

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Previous results on apple tissue equilibration during osmotic dehydration showed that, at very long processing times, the solute concentrations of the fruit liquid phase and the osmotic solution were the same. In the present study, changes in apple liquid phase composition throughout equilibrium in osmotic dehydration were analyzed and modeled. Results showed that, by the time osmosed samples reached the maximum weight and volume loss, solute concentration of the fruit liquid phase was higher than that of the osmotic solution. The reported overconcentration could be explained in terms of the apple structure shrinkage that occurred during the osmotic dehydration with highly concentrated osmotic solutions due to the elastic response of the food structure to the loss of water and intake of solutes. The fruit liquid phase overconcentration rate was observed to depend on the concentration of the osmotic solution, the processing temperature, the sample size, and shape of the cellular tissue.

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Salting is one of the most important stages of the traditional process of cured ham manufacturing. During pile salting a saturated brine is formed and drips through the orifices located at the bottom of the salting containers. The objective of the present work was to quantify the released brine in the ham manufacturing industry in Spain and to relate the brine generation with the salt gained by hams in the process. The total released brine during ham and shoulder salting in Spain was determined theoretically and from the experimental values obtained from the industry (around 38,000 metric tons in 2002). In addition to that, an easy method for the estimation of the NaCl gained by hams and shoulders was developed by using the measurements of the released brine (the estimated NaCl gained differed 3.5% from the experimental data).

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The use of the simultaneous brine thawing/salting on frozen raw material was compared in a previous work with the traditional pile salting method. The aim of this study was to characterise and compare the post-salting stage in Spanish cured ham production by processing fresh and thawed raw material with the traditional pile salting method (which can be considered as the reference method), with the results obtained using the brine thawing/salting method, with and without applying vacuum impregnation. The obtained results show that the thawed salted hams exhibited a higher NaCl diffusion than the fresh ones, implying a shorter post-salting period. Post-salting stage could be reduced from the 50 days employed in the traditional fresh raw material salting, to 25 days when using frozen hams brine thawed/salted. No influence of the use of vacuum impregnation during the salting stage was observed on the post-salting period.

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Salting, is one of the fundamental operations in Spanish cured ham manufacturing, and is basic in order to preserve the product throughout its processing and storage. Pile salting is the method traditionally employed to accomplish this step. The use of frozen raw material has become quite frequent in the industry, and it implies a preliminary thawing step in a cold chamber. The aim of this study is the analysis of the first step in ham production (salting) and the influence of simultaneous brine thawing/salting and vacuum impregnation in the salting stage of Spanish cured ham. The results indicated a reduction in the salting time when using the brine thawing/salting method, which was performed together with vacuum impregnation. Further studies need to be done in order to fully understand the influence of these new salting methods on the following manufacturing steps and the final quality characteristics.