Time filter

Source Type

Cofrades S.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Santos-Lopez J.A.,Complutense University of Madrid | Freire M.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Benedi J.,Complutense University of Madrid | And 2 more authors.
LWT - Food Science and Technology | Year: 2014

The aim of this paper was to evaluate the oxidative stability of healthier lipid cooked meat systems (MS) in which pork backfat was replaced by a double emulsion (DE, W1/O/W2) prepared with hydroxytyrosol (HXT) within an inner aqueous phase and chia oil as lipid phase. Physical characteristics of DEs and oxidative stability of DEs and MS during chilled storage were analysed. In DEs, which were highly stable, the presence of HXT improved oxidative stability, increasing (P < 0.05) DPPH free radical scavenging and ferric reducing ability (FRAP) and reducing (P < 0.05) levels of thiobarbituric acid-reactive substances (TBARS). In MS, replacement of pork backfat by chia oil promoted lipid oxidation, which was more pronounced when chia oil was incorporated in the DE than when it was added in liquid form. HXT demonstrated antioxidative capacity, although it was less efficient when incorporated as part of a W1/O/W2 emulsion. In conclusion, MS including DE formulated with chia and HXT display oxidative stability throughout their commercial life, assuring successful development of potential healthier meat products. © 2014 Elsevier Ltd.


Herranz B.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Borderias A.J.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Solas M.T.,Complutense University of Madrid | Tovar C.A.,University of Vigo
Food Research International | Year: 2012

Samples of 3% glucomannan gels made with 0.6M KOH and preheated at T ht: 25°C (A), 50°C (B), 70°C (C) and 90°C (D) were studied at two measurement temperatures (T m: 50 and 70°C) and compared to T m: 25°C. Samples B and C were gels more thermo-stable at high measurement temperatures. This means that a preliminary heating at 50 and 70°C would be needed to retain their structural integrity of these gels. When the preheated gels were subjected to high deformation (puncture test), rigidity increased with increasing T m. Similarly, small deformation tests showed that at T m: 50°C and 70°C, the C sample had better gel characteristics than the others: i.e. higher elasticity and lower frequency-dependence of viscoelastic moduli. This means that there was more particle aggregation, so that when gels C were heated they would maintain a high degree of internal cohesion and connectivity. Mechanical and rheological analyses were consistent with the structures shown in SEM photographs. © 2012 Elsevier Ltd.


Herranz B.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Borderias A.J.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Solo-de-Zaldivar B.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Solas M.T.,Complutense University of Madrid | Tovar C.A.,University of Vigo
Food Hydrocolloids | Year: 2012

This paper examines the thermostability of glucomannan gels (3 and 5 %) deacetylated with 0.6 N KOH (A3, A5) and 1 N NaOH (B3, B5) at both concentrations. Gels were heated at heat treatment temperature (T ht): 25, 50, 70 and 90 °C for 20 min. Different analyses: puncture, small amplitude oscillatory shear (SAOS) and scanning electron microscopy (SEM) were made at 25 °C. All gels (irrespective of alkali and glucomannan concentration) behaved as thermo-irreversible with permanently bonded networks. Some structural differences were found depending on the alkali and glucomannan concentration and T ht range: increased T ht produced stronger networks in A3 and B3, which were more orderly in A3. At high T ht, A3 had a more elastic network, with higher water binding capacity (WBC) than B3. At 5% glucomannan, gel networks (A5-B5) were tighter and were less reinforced by temperature. Mechanical and rheological analyses were consistent with the structures shown in SEM photographs. © 2012 Elsevier Ltd.


Sanchez-Alonso I.,CSIC - Institute for the Structure of Matter | Martinez I.,University of the Basque Country | Martinez I.,University of Tromsø | Martinez I.,Ikerbasque | And 2 more authors.
Food Chemistry | Year: 2012

The potential of low field NMR (LF NMR) as a fast monitoring technique to estimate the quality of hake (Merluccius merluccius) frozen stored at -10 °C for up to 6 months was evaluated. LF NMR clearly detected three populations of water: water strongly bound to macromolecules (T2b), trapped water (T21) and free water (T22). As storage time increased, and concomitant with an increase in the T22 and a decrease in the T 21 water populations, the water holding capacity (WHC) and apparent viscosity values decreased and the shear strength increased, reflecting the characteristic loss of juiciness and tougher texture developed by hake during frozen storage. Two mathematical models were constructed: a simple regression using the biexponential analysis of the relaxation times (T21, T 22) and amplitudes (A21, A22) and a partial least square regression (PLS) of CONTIN analysis. Both models seemed suitable to estimate the quality of the product. © 2012 Elsevier Ltd. All rights reserved.


Sanchez-Alonso I.,CSIC - Institute for the Structure of Matter | Sanchez-Alonso I.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Moreno P.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Careche M.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic
Food Chemistry | Year: 2014

Low field NMR T2 transverse relaxation measurements were performed on muscle samples from sixty hake (Merluccius merluccius, L.). Fish fillets from hake stored in ice for 3 and 14 days were subjected to different freezing methods (air blast, liquid nitrogen or walk-in freezer) and storage conditions (-20 and -10 C for 5 days, 8 and 18 weeks). Distribution analysis of T2 data of unfrozen muscle displayed a major band (T21), accounting for 90-92% of the total signal, with a relaxation time centred at 47-60 ms and a broad band with protons of higher mobility between 300 and 800 ms, accounting for 3-5% of the signal. Upon freezing, T21 became wider and an extra band appeared within the range 120-360 ms. Whereas no changes were detected at -20 C, the T21 time constant decreased during frozen storage at -10 C in a similar way for all three freezing methods. The relative abundance of T21 declined with storage time but differences were found as a function of freezing. Results are discussed in the light of morphological alterations and protein denaturation, and it is concluded that LF NMR relaxometry is sensitive to different freezing and frozen storage conditions which can have important implications for the quality of fish muscle. © 2013 Elsevier Ltd. All rights reserved.


Del Castillo M.L.R.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Rodriguez-Valenciano M.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | De La Pena Moreno F.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Blanch G.P.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic
Talanta | Year: 2012

A new method based on the use of SPME followed by the MDGC-MS analysis was developed to determine pesticides in fruit juice. Different pesticide mixture standards (i.e. Mix 101, 13 and 164) were initially analyzed to optimize the separation conditions. To evaluate the advantages of the two-dimensional system over monodimensional GC, a comparative study on relative standard deviations, detection limits and correlation coefficients was carried out. As a result, selective transfers of some pesticides from the first to the second dimension were at times essential to avoid overlapping. The selected separation conditions from the study with standards were applied to fruit juices spiked with some pesticide standards. The results found in this work prove that the employment of a multidimensional analysis technique permits to avoid false positives obtained frequently on monodimensional techniques as a consequence of interferences of the analytes with matrix components. © 2011 Elsevier B.V. All rights reserved.


Lopez-Tobar E.,CSIC - Institute for the Structure of Matter | Blanch G.P.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Ruiz Del Castillo M.L.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Sanchez-Cortes S.,CSIC - Institute for the Structure of Matter
Vibrational Spectroscopy | Year: 2012

FT-Raman and UV-visible adsorption spectroscopy are applied for the first time in the structural study of the antioxidant, antitumoral polyphenol curcumin and its complexation with β- and γ-cyclodextrin. Additionally, high performance liquid chromatography linked to UV spectroscopy was employed to monitor the encapsulation yield of curcumin. These techniques indicate that the effectiveness of the encapsulation is higher in the case of γ-cyclodextrin (γ-CD) likely due to the better fit of the polyphenol size with the dimensions of the γ-CD cavity. Raman spectra provided specific structural information from the ligand which indicates that the encapsulation takes place at the level of the aromatic rings, through H-bonds, and that a tautomerization from the planar keto enol form to the non-planar diketo form of curcumin also occurs. These changes may lead to an increase of the chemical stability, the bioavailability and the biological activity of curcumin. © 2012 Elsevier B.V.


Reveron I.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | de las Rivas B.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Munoz R.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Lopez de Felipe F.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic
Molecular Nutrition and Food Research | Year: 2012

Scope: To advance knowledge of the stress tolerance mechanisms of a probiotic Lactobacillus plantarum strain to dietary hydroxycinnamic acids and the role of gut commensal microorganisms in the bioactivation of polyphenols. Methods and results: To understand how gut commensal microorganisms tolerate toxicity of hydroxycinnamic acids and bioactivate these compounds, we used whole genome transcriptional profiling to characterize the response of a L. plantarum human isolate during challenge with p-coumaric acid (p-CA). The transcriptional profile reveals a massive induction of genes involved in stress resistance and detoxification-related functions and a global shutdown of growth-associated processes. A specific oxidative stress response, including a large reshape of nitrogen metabolism toward methionine production, was induced, probably to counteract a p-CA-induced oxidative protein stress. The transcriptional datasets revealed overlapping behaviors with the response of L. plantarum to the gut environment. Conclusion: Contact with p-CA triggers responses that would be potentially beneficial for the intestinal function such as detoxification of dietary hydroxycinnamic acids and induction of a marked antioxidant response. Elicited responses indicated that contact with p-CA could provide preparedness to L. plantarum for adaptation to the gut environment. This knowledge facilitates the way to design methods to improve probiotic cell survival in this habitat. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Herranz B.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Tovar C.A.,University of Vigo | Solo-de-Zaldivar B.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Borderias A.J.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic
LWT - Food Science and Technology | Year: 2013

The effect of type and concentration of alkali on 5 g/100 mL of glucomannan gels was examined in depth by mechanical and thermo-rheological analysis. Four KGM gels were made from aqueous glucomannan solutions deacetylated with 0.6 mol/L and 1 mol/L of KOH (A0 and A1) and NaOH (B0 and B1), respectively. At 25 °C all physical networks were too tight and dense due to the large number of extended junction zones, as indicated by the high breaking force (BF), complex modulus (G*) and low strain amplitude (γmax). The influence of alkali concentration was noticeable only in KOH gels, of which A0 was significantly more elastic and time stable than A1 over both short and longer-time scales. 0.6 mol/L KOH was the most suitable alkali, producing the most stable and homogeneous gel, with the highest level of connectivity, the lowest relaxation exponent (n) and the highest gel strength (S).Increasing temperature resulted in loss of elasticity in A0, where γmax, G* and S decreased, and the loss factor (tan δ), creep and recovery compliances (J) and n increased. Thus, the networks become less flexible and more unstable at high temperatures, especially between 25 and 50 °C. © 2012 Elsevier Ltd.


Solo-de-Zaldivar B.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Tovar C.A.,University of Vigo | Borderias A.J.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic | Herranz B.,Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic
Food Hydrocolloids | Year: 2014

This paper focuses on the relationship between network structure and physicochemical and rheological properties of aqueous glucomannan dispersions (AGD) as a function of pH, to establish optimal conditions of glucomannan gelation for making restructured seafood products. Various lots of AGD were prepared from 3% (L1) and 5% (L2) konjac glucomannan adding different amounts (0.5-5%) of 0.6N KOH to obtain samples with successively increasing degrees of alkalinity, from pH=8.9 to=11.9 (samples L1.1-L1.6 for 3% AGD) and from pH=7 to 11.4 (samples L2.1-L2.6 for 5% AGD). The spectra of the different AGDs were obtained by Fourier Transform Infrared spectroscopy (FT-IR) to quantify the deacetylation ratio, whose effect on the physicochemical, mechanical (puncture), viscoelastic (at both small and large time scales) and structural characteristics (scanning electron microscopy (SEM)) was analysed. A linear dependence was found between the relative area of acetyl bands of AGD and pH, showing a discontinuous region in the function or gap zone between pHs 9.3 (L1.2) and 9.8 (L1.3) for 3% AGD and between 9.2 (L2.3) and 10.7 (L2.4) for 5% AGD. Samples before the gap zone (L1.2 and L2.3) were gels of varying degrees of weakness, becoming strong gels thereafter. The gelation conditions were best at pH~10.7 for both 3 and 5% AGDs, corresponding to high and moderate deacetylation ratio, respectively. The resulting gels possessed elastic, cohesive and time-stable networks and thus formed basic structures able to contain several ingredients for making restructured seafood products. The SEM photographs corroborated the physicochemical and rheological characteristics. © 2013 Elsevier Ltd.

Loading Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic collaborators
Loading Institute Ciencia Y Tecnologia Of Los Alimentos Y Nutricion Ictan Csic collaborators