J. Antonio Torres | Tecnológico de Monterrey (original) (raw)

Papers by J. Antonio Torres

Innovative Food Science & Emerging Technologies, 2013

This work focused on assessing lipid damage during the storage of frozen Atlantic mackerel (Scomb... more This work focused on assessing lipid damage during the storage of frozen Atlantic mackerel (Scomber scombrus) subjected to a high hydrostatic pressure (HHP) treatment (150, 300, 450 MPa with holding times of 0.0, 2.5, and 5.0 min) prior to freezing. The extent of lipid hydrolysis (free fatty acids) and oxidation (peroxide, thiobarbituric acid reactive substance and fluorescent and browning compound formation) as well as the polyene content were analysed during 3 months of accelerated storage at-10ºC. A marked inhibition (p<0.05) of free fatty acids and tertiary lipid oxidation compounds formation during storage was observed when increasing the pressure level or the pressure holding time of the HHP treatment. However, only minor differences in the polyene index and no effect (p>0.05) in the content of primary and secondary oxidation compounds were observed .

Innovative Food Science & Emerging Technologies, 2014

Frozen storage of horse mackerel (Trachurus trachurus) is limited by lipid damage causing sensory... more Frozen storage of horse mackerel (Trachurus trachurus) is limited by lipid damage causing sensory quality losses. This work deals with changes in functional and sensory properties during frozen storage of horse mackerel treated by high hydrostatic pressure processing (HPP) prior to freezing. Three levels of pressure (150, 300, and 450 MPa), pressure holding time (0.0, 2.5, and 5.0 min), and frozen storage time (0, 1, and 3 months) were studied. Expressible water, colour parameters, mechanical texture parameters and sensory parameters were evaluated in raw and cooked samples. The texture profile analysis of raw and cooked HPP samples suggested that a product texture similar or close to fresh muscle is possible. The sensory analysis showed that a 150 MPa treatment yielded high acceptability values. Although acceptability decreased during frozen storage, values remained close to those of fresh samples.

Food and Bioproducts Processing

Abstract Consumer preferences, and potential health risks associated with the consumption of synt... more Abstract Consumer preferences, and potential health risks associated with the consumption of synthetic food colors, explain the commercial interest in alternatives from natural sources. Betaxanthins from cactus fruit have been used to color food products, but sugars are not usually removed from these extracts leading to processing and formulation challenges. In this study, low-sugar betaxanthin preparations were obtained from a crude yellow pitaya Stenocereus pruinosus extract using aqueous two-phase systems (ATPS). This study focuses on the effect of the salts and polymer choice (polyethylene glycol (MW 1000; PEG1000) or polyalkylene glycol copolymer (MW 3930, UCON), tie line length (TLL), phase volume ratio (Vr), and crude extract percentage on the partitioning of betaxanthins and sugars in the crude extract. PEG1000-phosphates were more suitable than UCON-salts for the extraction of betaxanthin. Multivariate analysis of variance (MANOVA, α = 0.05) showed that TLL, Vr and crude extract concentration effects were statistically significant (P

Journal of food science and technology, 2018

An undesirable crispiness loss occurs when some dry fruits reach a critical moisture content () a... more An undesirable crispiness loss occurs when some dry fruits reach a critical moisture content () and their glass transition temperature () matches the storage temperature. Models for sorption isotherms and onsetvalues for dry mango, apple, and banana were used to estimatevalues at 25 and 32 °C. All models yielded > 0.97 but information theory criteria strongly supported GAB in all but one case (40 °C, mango). The Gordon-Taylormodel (GT) yielded highvalues for apple and banana but resulted in = 0.834 for mango. As moisture approached zero, mangoestimates displayed a downward concavity contrasting with a rapidly increasing trend for apple and banana. The Khalloufi-Maslouhi-Ratti (KMR) model foras a function ofshowed a linear behavior. Although the KMR model fitted data with > 0.996, it requires more parameters and whenapproached 0, estimatedvalues increased at a slower rate than for the GT model. In the case of banana and mango, both models predicted approximately the sameat 25 °...

Journal of Food Protection

The growth rate and lag phase of Pseudomonas fluorescens, Brochothrix thermosphacta, Salmonella t... more The growth rate and lag phase of Pseudomonas fluorescens, Brochothrix thermosphacta, Salmonella typhlmurium, Enterococcus faecalis, and Staphylococcus aureus were studied in liquid media as a function of temperature, water activity (aw) and solute type. The lag phase lengthened and the growth rate decreased when the temperature was lowered or the aw reduced, and these variations depended on the aw-controlling solute. In general, the magnitude order of the solute effect on the growth rate parameters was glycerol < NaCl < sucrose. This effect can be related to the ability of the solutes to permeate the cell and can be explained by the osmoregulatory mechanism. The specific growth rate was not as sensitive to the aw-controlling solute as the lag phase. A linear extrapolation method was a reliable and convenient method to estimate the minimum aw for microbial growth.

Cienc Tecnol Aliment, 2007

Soluble proteins from surimi wash water (SWW) can be insolubilized by complexing with chitosan-al... more Soluble proteins from surimi wash water (SWW) can be insolubilized by complexing with chitosan-alginate allowing its recovery and the reduction of the organic matter in the processing water discharged from surimi processing plants. The objective of this work was to evaluate the effect of adding soluble proteins recovered from Pacific whiting SWW on the mechanical and functional properties of commercial

Food and Bioprocess Technology, 2015

This research focuses on biochemical changes related to quality losses observed in Atlantic macke... more This research focuses on biochemical changes related to quality losses observed in Atlantic mackerel (Scomber scombrus) muscle stored under commercial frozen storage conditions (9 months,-18 ºC) when subjected to high-hydrostatic pressure (HHP) treatments (125, 150, 175 and 200 MPa for 0 min) before freezing. After freezing, free fatty acid (FFA) formation (lipid hydrolysis assessment) showed a marked inhibition in HHP-treated fish and during frozen storage of samples treated at 175 MPa. Fluorescence ratio (FR) assessment of tertiary lipid oxidation showed a partial inhibitory effect during the 0-9-month period for samples treated at 175 and 200 MPa. After 3 months storage of samples treated at these pressure levels, one-dimensional SDS-PAGE analysis of the sarcoplasmic protein fraction revealed the disappearance of a band; additionally, samples treated at 150 MPa showed the same effect at month 9. After gel excision, trypsin digestion, tandem mass spectrometry (MS/MS) and sequence database analysis, the band was identified as phosphoglycerate mutase 2 (28.7 kDa). On the other hand, HHP processing did not show a significant effect on trimethylamine (TMA) values, primary and secondary lipid oxidation, PUFA levels, 1-D myofibril protein pattern and the activity of acid phosphatase and cathepsins B and D. Biochemical quality indices such as FFA, TMA, and FR, and the activity of acid phosphatase and cathepsin B showed a progressive increase throughout the frozen storage of all samples.

Handbook of Food Chemistry, 2014

Ciencia y Tecnologia Alimentaria, 2004

Edible barrier films complement modified atmosphere in preserving food quality and extending shel... more Edible barrier films complement modified atmosphere in preserving food quality and extending shelf life. The effects of plasticizer (stearic acid or propylene glycol), pH (4.4 or 9.4) and degree of hydration (58 or 84% RH) on the water vapor permeability, tensile strength and percent elongation at breakpoint were determined for zein and ethylcellulose films. Zein film hydration increased water permeability

Ciencia y Tecnologia Alimentaria, 2007

An optical method using a custom-built system was investigated to study heating effects on bovine... more An optical method using a custom-built system was investigated to study heating effects on bovine serum albumin (BSA) as affected by pH and ionic strength (IS). Changes in the optical rotation (OR) and transmitted light (TL) of BSA in 0.01 M phosphate buffer at pH 6.1, 7, and 7.9 with IS maintained at 0.04, 0.08, and 0.16 were monitored while heating the solution at ~6 °C/min from room temperature to ~85 °C. There was no significant effect of IS on BSA's denaturation temperature (T d) values. T d was affected by pH with lower values observed at pH 7.9 than at pH 7 but not statistically different from values at pH 6.1. Values at pH 6.1 and 7 were not significantly different either. These observations were consistent with literature values determined by differential scanning calorimetry. Changes in the TL signal, reflecting the formation of an opaque gel, were not detected at pH 7.9, identified only at the two highest IS at pH 7, and observed always at pH 6.1, i.e., closest to the pH value for the isoelectric point (pI) of BSA reported to be around pH 4.7 to 5.2. Promoting of gel formation by IS was attributed to the screening of intra-and intermolecular electrostatic forces. Resumen Un método óptico basado en un sistema experimental especialmente construido para este propósito fue usado para investigar la influencia del pH y la fuerza iónica sobre los efectos térmicos en la seroalbúmina bovina (BSA). Los cambios en la rotación óptica (OR) y la luz transmitida (TL) de soluciones buffer de fosfato 0,01 M con 2,5% de seroalbúmina bovina (BSA) a pH 6,1, 7 y 7,9 y una fuerza iónica (IS) de 0,04, 0,08 ó 0,16 fueron monitoreados durante su calentamiento a ~6 °C/min desde temperatura ambiente hasta ~85 °C. No se observó un efecto estadísticamente significativo de IS sobre la temperatura de desnaturalizacion térmica (T d). T d fue afectada por el pH con valores menores observados a pH 7,9 que a pH 7 pero no estadísticamente diferentes del valor a pH 6,1. Valores a pH 6,1 y 7 tampoco fueron estadísticamente diferentes entre ellos. Estas observaciones son consistentes con valores reportados en la literatura y obtenidos por el método de Calorimetría Diferencial de Barrido (DSC). Cambios en la señal de TL, reflejando la formación de un gel opaco, no fueron detectados a pH 7,9, encontrados solo a los valores mayores de IS a pH 7, y observados consistentemente a pH 6,1, el valor de pH incluido en este estudio más cercano al punto isoeléctrico de BSA y reportado entre pH 4,7 y 5,2. El efecto de la IS en la mayor formación de geles fue atribuido al su capacidad de bloquear fuerzas electrostáticas intra-e intermoleculares.

Journal of Dairy Science, 2006

Volatile sulfur compounds have been reported to be responsible for the sulfurous off-flavors gene... more Volatile sulfur compounds have been reported to be responsible for the sulfurous off-flavors generated during the thermal processing of milk; however, their analysis has been a challenge due to their high reactivity, high volatility, and low sensory threshold. In this study, reactive thiols were stabilized and the volatile sulfur compounds in milk were extracted by headspace solidphase microextraction, and analyzed by gas chromatography and pulsed-flame photometric detection. Calibration curves for 7 sulfur-containing compounds were constructed in milk by the standard addition technique. Raw, pasteurized, and UHT milk samples with various fat contents were analyzed. Compared with raw and pasteurized samples, UHT milk contained substantially higher concentrations of hydrogen sulfide, methanethiol, carbon disulfide, dimethyl trisulfide, and dimethyl sulfoxide. The high odor activity values calculated for methanethiol and dimethyl trisulfide suggested that these 2 compounds, in addition to dimethyl sulfide reported in a previous study, could be the most important contributors to the sulfurous note in UHT milk.

Ciencia Y Tecnologia Alimentaria, 2007