María Rosa Casales

Modifications in the chemical compounds and sensorial attributes of Engraulis anchoita fillet during marinating process

Marinated fish are fish products preserved by the combined action of salt and organic acids. The objective of this work was to analyze the variations in the chemical compounds of anchovy fillets that give them sensorial characteristics during the marinating process of Engraulis anchoita. The protein content decreased slightly and the TVB-N level decreased significantly in both the brining and marinating stages. In the marinating stage an increase in the total free aminoacids was observed. The NBV level in the brining and marinating solutions increased during these stages due to the solubilization of the non-protein nitrogenous compounds and the degradation of some protein compounds.The decrease of the contents of protein and TVB-N, and the increase of the acidity and the free aminoacids content during the marinating process give the marinated fillets the characteristic texture and aroma.

Influence of Water and Glycerol Contents on the aw of Fish Pastes

Abstract The influence of fish water content on the characteristics of water activity (aw) of reduced paste was studied. Two fish species were used: a fat species, mackerel (Scomber japonicus marplatensis), and a lean species, Brazilian sandperch (Pseudopercis semifasciata). Glycerol (from 15 to 50%) was used to decrease aw of the cooked fish paste.(54.12% and 77.89%) in mackerel, two relationships of aw versus percent added glycerol were obtained, and for Brazilian sandperch one relationship was obtained.

Psychophysical estimation of acid intensity and determination of sweet-acid interaction in a fish paste containing glycerol

In a fish paste made with cooked Brazilian flathead (Percophis brasiliensis), glycerol (17%), sodium chloride (1.5%) and potassium sorbate (0.1%) the following acid percentages: 0.2; 0.4; 0.6; 0.8, 1 and 1.5% w/w were incorporated to determine the relationship between added acetic acid and the sensorially perceived intensity, and the effects of the combination of sweet-acid tastes. Tests for paired comparison, ranking and structured verbal scales for sweet and acid attributes and psychophysical test were carried out. There was a perceptible difference among samples for differences of 0.4 units of acid concentration. Samples indicated as sweeter by 89.47% of the judges were those containing a lesser acid concentration. A reduction in glycerol sweetness when increasing acid levels was observed. Acetic acid reduced the sweetness of glycerol and inversely glycerol reduced the acidity of acetic acid. The data obtained with the magnitude estimation test agree with Stevens law.

Mass Transfer Modeling During Marination of Anchovy Fillets in Ternary and Multicomponent Solutions

ABSTRACT We assessed the applicability of three mathematical models (i.e., the Peleg, Zugarramurdi and Lupin and Weibull models) for water loss and solute gain of marinated Engraulis anchoita. The marinating stage was performed in a ternary solution of water/salt/acid and in a multicomponent solution of water/salt/acid/sorbitol. Based on the statistical parameters (R2 > 0.96; 0.001 < RMSE < 0.032), the models were able to predict the salt and acid gains upon marinating in the water/salt/acid solution. Water loss and solute gain could be estimated by all of the proposed models (R2 > 0.89; 0.003 < RMSE < 0.080) for the water/salt/acid/sorbitol marinating solution. The Peleg, Zugarramurdi, and Lupin and Weibull models can thus be used to represent the kinetics of mass transfer for water and solutes for marinated anchovies.

Analysis of applicability of Peleg model to the cooking-infusion of mackerel (Scomber japonicus) slices

Mass transfer kinetics in osmotic dehydration is usually modeled by Ficks law, empirical models and probabilistic models. The aim of this study was to determine the applicability of Peleg model to investigate the mass transfer during osmotic dehydration of mackerel (Scomber japonicus) slices at different temperatures. Osmotic dehydration was performed on mackerel slices by cooking-infusion in solutions with glycerol and salt (aw = 0.64) at different temperatures: 50, 70, and 90 oC. Peleg rate constant (K1) (h(g/gdm)-1) varied with temperature variation from 0.761 to 0.396 for water loss, from 5.260 to 2.947 for salt gain, and from 0.854 to 0.566 for glycerol intake. In all cases, it followed the Arrhenius relationship (R2>0.86). The Ea (kJ / mol) values obtained were 16.14; 14.21, and 10.12 for water, salt, and glycerol, respectively. The statistical parameters that qualify the goodness of fit (R2>0.91 and RMSE<0.086) indicate promising applicability of Peleg model.