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Pilar Buera

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Clare A. A Sammells

Bucknell University

Salomón Hocsman

Universidad Nacional de Tucuman

Viacheslav Kuleshov

Stockholm University

Professor Bashir O M O L A R A N Bello

University of Abuja, Nigeria

Universitat de Barcelona

Prof.Dr. Hakan Ulukan

Ankara

Ravi Aims Jaipur

Rajasthan Technical University

Institut Mines-Telecom

University of Pretoria

Patricia Krawczak

Institut Mines-Telecom

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Papers by Pilar Buera

Detection of quinoa flour adulteration by means of FT-MIR spectroscopy combined with chemometric methods

Food Chemistry, Feb 1, 2019

Quinoa flour has been receiving an increasing attention as a substitute for wheat flour in bread ... more Quinoa flour has been receiving an increasing attention as a substitute for wheat flour in bread formulations due to immuno-nutritional features. This growing interest in quinoa has increased the demand and consequently the prices, being a target for possible adulterations with cheaper cereals. Fourier transform Mid-infrared spectroscopy (FT-MIR) was used in the present work as a fingerprinting technique to detect the presence of three adulterants (soybean, maize and wheat flours). Partial least squares discriminant analysis (PLS-DA) and soft independent modelling of class analogy (SIMCA) models were used to classify pure from adulterated samples. 414 samples were measured, including pure quinoa flour, pure adulterant flours and adulterated quinoa flours using three different proportions (10, 5 and 1% w/w). PLS-DA showed better classification results than SIMCA, with error rates from 2 to 8% for the three strategies used to detect the presence of adulterants.

Efecto de la formulación y las condiciones de procesamiento sobre el desarrollo del pardeamiento no enzimático y la estabilidad de carotenoides en copos de maíz

Biolatto, Andrea, Guidi, Silvina, Nanni, Mariana y Troilo, Liliana (Comps.). (2018). Desarrollo Tecnológicos en el marco del Programa Nacional de Agroindustria y Agregado de Valor. - 1a. ed. - [s.l] : Ediciones INTA. [s.p.], Aug 1, 2018

El proceso de producción dc copos de malz por laminación comprende las etapas de cocción al vapor... more El proceso de producción dc copos de malz por laminación comprende las etapas de cocción al vapor, atemperado, laminado y tostado. Durante la cocción)' además en el tostado, ocurre la reacción de Maillard! favorecida por las elevadas temperaturas y el bajo contenido de agua en este último paso. Además, se produce la pérdida de compuestos de interés. como los carotenoides. Los diferentes ingredientes que constituyen la fonnulación de los copos de malz influyen sobre el color)' eljlavor del producto final y, por lo tanto. sobre la aceptación por parte de los consumidores. Sin embargo. en el proceso también se forman ciertos compuestos indeseables. Por lo tanto. es importante evaluar cl papel de la formulación)' del tiempo de lOstado en el desarrollo de color y la formación de marcadores químicos. Los copos de maíz se equilibraron a OM' 0.8 Y tostaron a 230°C. Luego de la extracción de pigmentos Ouorcscentes con pronasa se rc..'llizaron análisis de fluoresccncia., absorbancia a 420 nm, coordenadas de color y contenido de furfurales. Por otro lado. se evaluó la estabilidad de los carotenoides en las distintas etapas del proceso de elaboración. Respecto a la formulación. la sacarosa mostró un efecto sinérgico con la sal y la malta para acelerar la reacción de Maillard. La formulación afectó significativamente la cantidad de HMF y furfural formados. Los parámetros cromáticos Lt. y 0* fueron variables adecuadas para evaluar reacción de pardeamiento. Durante el proceso de cocción sc-perdió un 60% de lutcína y un 40% dc 7.eaxantina. Lucgo dcl tostado. la ctapa final. el porcentaje de pérdida de ambos compuestos fuc del 80%. Estos resultados permiten profundizar en el conocimiento de las reacciones que ocurren durante el procesamiento de los cereales. para poder definir las condiciones que disminuyan la generación de compuestos indeseables y la mayor retención de las sustancias de interés. Palabras clave: maiz. furfurales, fluorescencia. color, carotenoides Corn flakes produetion ineludes 1bur stages: steam cooking, drying. lamination and toasting. During steam cooking and toasting stagcs. Maillard reaclion takcs place. enhanced by the high tempcrature and the low water contenl. Morcovcr, sorne componcnts of interest are 1051. such as carolenoids. The difTerent ingredients that constitute the com flake formulation innuence color and navor 01' the final product ando thercfore, on consumer acceptancc. However, during processing. certain undesirable compounds are al so formcd. Thus. it is important to cvaluatc the importance of the ingrcdients and toasting timc on the color development and the formation 01' chemical markers. Coro llakes weTe equilibrated at 0li-0.8 and toasted at 230°C. After fluorescent pigmcnts extraction with pronase, l1uorcscencc, absorbance al 420 nm. color coordinates and furfurals content analysis ""ere perfomlcd. On the other hand. the stability of carolenoids during the difTerent stages of elabol'ation was analyzed. Regarding lhe formulation. sucrose showed a synergistic effect with salt and malt, enhancing the Maillard reaetion. Formulation signHicantly affected the amollnt of HMF and furfurals formed. Chromatic paramctcrs L * and 0* were-proper variables evaluated in relation with the browning reaction. During cooking. 60% of lutcin and 40% of 7.caxanthin \Vere lost. Aftcr toasting. the final stagc, the pcrccntage of loss was 80% for both compounds. These results allow furthcr understanding of the rcactions that take place during cereal processing, in order to define lhe best conditions to deerease the formation of undesirable compounds and the highest retention of substances of interest.

Multi-analytical Approach to Oxidative Stability of Unrefined Argan, Chia, Rosa Mosqueta and Olive Oils

Journal of Nutrition & Food Sciences, 2016

Fresh, unrefined argan (AR), chia (CH), rosa mosqueta (RM) and olive (OL) oils were evaluated for... more Fresh, unrefined argan (AR), chia (CH), rosa mosqueta (RM) and olive (OL) oils were evaluated for thermal stability with dielectric spectroscopy, differential scanning calorimetry, peroxide values (PV) and free fatty acids (FFAs). The dielectric constant ('), dielectric loss (''), and melting temperature (T m ) of the oils correlated with degree of unsaturation, with the highest static dielectric constant (εs') for CH oil (3.311), the most unsaturated. AR and CH oils showed the highest electrical conductivities at 500 Hz (505, 230 pS/m, respectively), and CH and RM oils the lowest T m (-41.0, -36.6°C, respectively). All oils stored at 65°C for 432 hr showed minor changes in εs'. After 180°C for 28 h, εs' and ε'' increased from 5% to 7%. Initial PVs of these oils were <3.7 mmol O 2 /kg, and for highly unsaturated CH oil this increased to 221 mmol O 2 /kg after 65°C for 432 hr. At 180°C, the FFAs increased in all oils, except AR oil. Oxidation onset temperature of the oils correlated with PVs after 65°C for 432 h (r=-0.91) and with FFAs and εs' after 180°C for 28 hr (r=-0.81, -0.83, respectively).

Solubility, sorption isotherms and thermodynamic parameters of β-cyclodextrin complexes with poplar propolis components: Practical implicances

LWT

Thermal transitions and enthalpic relaxations as related to the stability of microencapsulated paprika powders

Journal of Food Engineering, 2019

Present work investigates the effect of thermal transitions and enthalpy relaxation phenomenon on... more Present work investigates the effect of thermal transitions and enthalpy relaxation phenomenon on the physico-chemical stability of paprika microencapsulated powders. Wall materials were combinations of soy protein isolates, maltodextrin and gum arabic. Powders stability was evaluated through the solid-water interactions, determined by sorption kinetics, calorimetry and color changes. The water sorption isotherms were well described by the GAB model. Below the critical condition, a w 0.6 and water content 11 % (d. b.) the systems were in amorphous state at 25 °C, and enthalpy relaxations were detectable as endothermal events in the stored samples. The magnitude of the enthalpy relaxations increased with storage temperature below T g and with time of storage. In the amorphous microencapsulates, luminosity changes measured as (L o *-L*) values decreased as a function of time and a w , indicating pigment decoloration. The kinetics of the enthalpy relaxations changes, instead of the punctual values of the variables under study, were related to the dynamics of deteriorative changes. It can be concluded that enthalpy relaxation phenomenon can be established as a criterion for defining storage conditions or predict changes in microencapsulated and other systems that have to be stored in the glassy state. Highlights Kinetics of encapsulated paprika discoloration were related to enthalpy relaxations. Changes in glassy state can be related to enthalpy relaxation phenomenon. Enthalpy relaxations can serve for predicting changes in glassy state.

Crystallization kinetics of lactose in sytems co-lyofilized with trehalose. Analysis by differential scanning calorimetry

Food Research International, 2001

The objective of the present work was to study by differential scanning calorimetry phase/state t... more The objective of the present work was to study by differential scanning calorimetry phase/state transitions in model systems of amorphous lactose and lactose co-lyophilized with trehalose. The obtained parameters, such as glass transition temperatures (T g) and enthalpies of crystallization were employed to test the applicability of different proposed models to predict the behavior of these systems. Thermograms of low moisture lactose-trehalose mixtures showed only one glass transition temperature indicating that compatibility exists between both sugars. The increase of trehalose concentration in the mixture promoted a delay of lactose crystallization in isothermal runs, and of the crystallization temperature (T cr) in dynamic experiments. The presence of trehalose delayed lactose crystallization, without affecting the T g value. Several factors (thermodynamic, geometric, kinetics) may modify the molecular environment in the combined systems, affecting nucleation and/or crystal growth. Three models [Arrhenius, Williams-Landel-Ferry (WLF) and Vogel-Tamman-Fulcher (VTF)] were used to study the temperature dependence of the crystallization time. Although experimental points were fitted fairly well by all these models in the range of temperature from 14 to 59 C above T g value, the VTF equation appears to apply better for sugars.

Food Color and Appearance Food Appearance and Expectations J. B. Hutchings, M. R. Luo, and W. Ji ... more Food Color and Appearance Food Appearance and Expectations J. B. Hutchings, M. R. Luo, and W. Ji Color and Visual Appearance in Foods R. D. Lozano Colors Seen through Transparent Objects O. Da Pos and C. Rao What Is the Color of a Glass of Wine? I. Jung, P. Jokela, P. Brandt, and O. Victor Color as a Code in Food Packaging: An Argentine Case M. L. Musso Effect of Illuminance and Correlated Color Temperature on Visibility of Food Color in Making Meals S. Okuda , Y. Fukumoto, N. Hara , H. Iwade, and W. Iwai Effect of Hydrothermal Conditions on Translucence of Milled Rice M. O. Bello, R. J. Aguerre, M. P. Tolaba, and C. Suarez Measuring Banana Appearance Aspects Using Spectrophotometer and Digital Camera W. Ji, M. R. Luo, and J. B. Hutchings Food Colorimetry and Color Scales Is the Color Measured in Food the Color That We See? A. I. Negueruela Whiteness, Yellowness, and Browning in Food Colorimetry: A Critical Review R. Hirschler Color Classification of Veal Carcasses: Past, Present, and Future M. l Lucassen, J. Alferdinck, and R. Van Megen Application of Image Analysis to the Color-Phenolic Composition Relationships of Grape Seeds F. J. Rodriguez-Pulido, F. J. Heredia, J. M. Zaldivar -Cruz, and M. L. Gonzalez-Miret Sensing Chlorophyll, Carotenoids, and Anthocyanins Concentrations in Leaves with Spatial Resolution from Digital Image G. Cordon and M. G. Lagorio Color of Honeys from the Southwestern Pampas Region: Relationship between the Pfund Color Scale and CIELAB Coordinates L. M. Gallez, A. Marconi, E. Tourn, M. L. Gonzalez-Miret, and F. J. Heredia Influence of Different Backgrounds on the Instrumental Color Specification of Orange Juices C. M. Stinco, R. Fernandez-Vazquez, A. J. Melendez-Martinez, F. J. Heredia, E. Bejines Mejias, and I. M. Vicario Color Change as Quality Index of Food Color Determination in Dehydrated Fruits: Image Analysis and Photocolorimetry L. M. Agudelo Laverde, N. Acevedo, C. Schebor, and M. P. Buera Color Study at Storage of Lyophilized Carrot Systems A. V. Gallo, M. P. Buera, and C. Petriella Temperature Abuses during Lettuce Postharvest: Impact on Color and Chlorophyll M. V. Aguero, A. E. Bevilacqua, and S. I. Roura Changes in Color and Anthocyanin Content of Different Dried Products Based on Sweet Cherries L. Franceschinis, C. Schebor, and D. M. Salvatori Color Measurement of Nova Mandarins Submitted to Heat and Degreening Treatments during Long Storage S. Guidi, A. M. Sancho, G. Polenta, G. Meier , D. Vazquez, and C. Gonzalez Color of Vacuum-Packed Squid (Illex argentinus) Mantle Rings Treated with Gamma Radiation A. Tomac and M. I. Yeannes Evaluation of Blueberry Color during Storage by Image Analysis S. Matiacevich, P. Silva, F. Osorio, and J. Enrione Effect of Washing-Disinfection Conditions on Total Anthocyanin Retention and Color of Fresh-Cut Strawberries F. Van de Velde, M. Pirovani, D. Guemes, and A. Piagentini Effects of Postharvest Treatments in Ruby Red Grapefruit Quality A. M. Sancho, S. Guidi, A. Biolatto, A. Pazos, and G. M. Grigioni Color Variation in Nut Kernels During Storage under Different Drying Methods L. Pilatti, A. M. Sancho, M. Irurueta, and G. M. Grigioni Kinetics of Melanosis in Shrimp: Effect of Pretreatment Using Chemical Additives M. A. Loubes, C. A. Almada, and M. P. Tolaba Color of Dried Pears as Affected by Prior Blanching and Sugar Infusion S. B. Maidana, M. B. Vullioud, and D. M. Salvatori Color Changes in Fresh-Cut Fruits as Affected by Cultivar, Chemical Treatment, and Storage Time and Temperature A. Piagentini, L. Martin, C. Bernardi, D. Guemes, and M. Pirovani Cross-Sectional Color Evaluation in Borage Stems G. Alcuson, A. M. Ruiz De Castro, M. C. Urzola, R. Oria, and A. I. Negueruela Color as an Index of Food Composition and Properties Spectral Signatures: A Way to Identify Species and Conditions of Vegetables J. D. Sandoval , S. R. Gor, J. Ramallo, A. Sfer, E. Colombo, M. Vilaseca, and J. Pujol Control of Animal Stress and Welfare with Measurements of Skin Color Variation: A New Field of Applications of Colorimetry in Applied Psychology P. F. M. Conceicao Relationship between Mineral Content and Color in Honeys from Two Ecological Regions in Argentina G. P. Balbarrey , A. Andrada , J. Echazarreta, D. Iaconis, and L. M. Gallez Importance of Anthocyanic Copigmentation on the Color Expression of Red Wine in Warm Climate B. Gordillo, M. L.Gonzalez-Miret, and F. J. Heredia Color-Composition Relationships of Seeds from Red Grape Varieties M. J. Jara-Palacios, J. M. Zaldivar-Cruz, F. J. Rodriguez-Pulido, D. Hernanz, F. J. Heredia, and M. L. Escudero-Gilete Color as an Indicator for the Maillard Reaction at Mild Temperatures: The Effect of Reducing Sugars G. Leiva , L. Guida, G. Naranjo, and L. Malec Statistical Relationships between Soil Color and Some Factors of Soil Formation A. Marques-Mateu, S. Ibanez, H. Moreno, J. M. Gisbert, S. Balasch, and M. Aguilar Color Characteristics of Raw Milk from Silage and Alfalfa-Fed Cows L. Langman, L.…

Appli cations in food science ’

Cyclodextrins (CDs) are cyclic oligosaccharides composed of linked glucopyranose subunits. The ma... more Cyclodextrins (CDs) are cyclic oligosaccharides composed of linked glucopyranose subunits. The main property of CDs is that their hydrophobic inner cavity forms inclusion complexes with a wide range of guest molecules, while the hydrophilic exterior enhances CD solubility in water. Because of their molecular inclusion capability, the properties of the materials with which they complex can be significantly modified. Particularly, solubility and stability of bioactive compounds to be used as nutraceuticals, could be improved by encapsulation in CDs. The available thermodynamic data are consistent with an exothermic and spontaneous inclusion processes. Phase solubility studies in liquid systems along with studies of physical properties of solids complex, help to elucidate complex stoichiometry and guest-CD interactions. The use of CD-complexes for improving molecules solubility and stability, for control release and as adjuvant in extraction processes, represents a promising innovative...

Toasting Time and Cooking Formulation Affect Browning Reaction Products Development in Corn Flakes

Cereal Chemistry Journal, 2016

Cereal Chem. 94(3):380-384 During toasting, the last stage of corn flake production, Maillard rea... more Cereal Chem. 94(3):380-384 During toasting, the last stage of corn flake production, Maillard reaction takes place, favored by the high temperature and low water content. The cooking formulation ingredients influence color and flavor of the final product and, therefore, consumer acceptance. However, some undesirable components are also formed. The impact of cooking formulation and toasting time on color development and on the formation of chemical markers was investigated. Samples (flakes) were equilibrated at water activity (a w) 0.8 and toasted at 230°C. After extraction of fluorescent pigments with pronase, fluorescence, absorbance at 420 nm, and furfurals analysis was performed. Sucrose showed a synergistic interaction with malt and salt. Formulation highly affected the amount of 5-hydroxymethylfurfural and furfural formed. L* and a* were sensitive variables to measure overall browning reaction. These results allow for further understanding of the influence of formulation used during cooking and would help to mitigate the formation of undesirable compounds.

Sucrose hydrolysis in a glassy starch matrix

LWT - Food Science and Technology, 1995

ABSTRACT The purpose of present work was to investigate whether the glassy state may prevent sucr... more ABSTRACT The purpose of present work was to investigate whether the glassy state may prevent sucrose inversion in an acid-containing amorphous starch powder (native or pre-gelatinized). It was found that sucrose hydrolysis occurred to a significant extent in the glassy state (in both native and gelatinized starch). Moisture content of the system affected the extent of sucrose hydrolysis but its effect was not attributable to the plasticizing effect of water. Little reaction occurred at moisture contents below the so-called B.E.T. monolayer. Temperature was a critical factor controlling sucrose inversion.

Effect of glass transition on rates of nonenzymic browning in food systems

Journal of Agricultural and Food Chemistry, 1992

Department of Food Science and Center for Advanced Food Technology, Rutgers University, PO Box 23... more

Retention of β-galactosidase activity as related to Maillard reaction, lactose crystallization, collapse and glass transition in low moisture whey systems

International Dairy Journal, 2004

Retention of b-galactosidase activity was analyzed in whey model systems in relation to browning ... more Retention of b-galactosidase activity was analyzed in whey model systems in relation to browning development and physical characteristics of the matrix (degree of matrix compression, crystallinity, glass transition). Amorphous systems were obtained by freeze-drying solutions containing b-galactosidase and reduced lactose milk whey, with or without maltodextrin. Samples (porous or previously compressed) were exposed to atmospheres of relative humidities of 0%, 22% or 44% and stored at 70 C. Remaining enzymatic activity and color development were determined at selected time intervals. The decrease of enzyme activity was simultaneous to browning development, which was in turn accelerated in the low porosity samples and affected by the glass transition of the systems and lactose crystallization. The addition of maltodextrin improved retention of enzyme activity and delayed both browning development and lactose crystallization.

A study of acid-catalyzed sucrose hydrolysis in an amorphous polymeric matrix at reduced moisture contents

Food Research International, 1995

The changes in viscosity and mobility which take place in the proximity of the glass transition a... more The changes in viscosity and mobility which take place in the proximity of the glass transition affect the physical stability of amorphous foods and could also affect the rate of chemical reactions. The effect of glass transition on the rate of acid-catalyzed sucrose hydrolysis was investigated in an amorphous polymeric matrix of polyvinylpyrrolidone (PVP). Aqueous solutions of PVP-sucrose in a citrate buffer were freeze-dried in order to obtain the amorphous matrix. Samples were then equilibrated to several relative humidities and stored at several temperatures. The difference between the glass transition temperature (T,) and the storage temperature (T), T-T,, was not a key factor determining the rate of sucrose hydrolysis, which was controlled by the water content of the system. The major effect on the rate of hydrolysis was related to changes in pH which occur when the system is dehydrated. Knowledge of the actual pH of a system, and the possible changes that may occur during concentration/drying are necessary for a better understanding of chemical changes in low and intermediate moisture foods.

Effect of physical changes on the rates of nonenzymic browning and related reactions

Food Chemistry, 1995

Nonenzymic browning (NEB) due to reaction of D-XylOSe and L-lysine was studied in a dehydrated ma... more Nonenzymic browning (NEB) due to reaction of D-XylOSe and L-lysine was studied in a dehydrated matrix based on poly(vinylpyrrolidone) (PVP) of different average molecular weights. Physical changes (collapse) and NEB were studied temperatures (T) and moisture contents resulting in different values of (T-T,), where TB is the glass transition temperature. Nonenzymic browning rates at low and intermediate moisture contents in a polymeric matrix above its glass transit@ were shown to be closely related to (T-T,). The initially porous matrices underwent a time-dependent shrinkage (collapse) above Tg and this shrinkage increased the rate of browning, presumably by minimizing diffusion paths for reactants. When the reactants (xylose and lysine in PVP) were separated by a reactantfree layer of PVP, the reaction rate decreased as the thickness of the empty layer increased. A lag time was observed, which was directly related to the thickness of this layer.

Color formation due to non-enzymatic browning in amorphous, glassy, anhydrous, model systems

Food Chemistry, 1999

Polymeric matrix model systems (gelatinized starch, maltodextrin and polyvinylpyrrolidone (PVP) M... more Polymeric matrix model systems (gelatinized starch, maltodextrin and polyvinylpyrrolidone (PVP) MW 40 000) containing a low concentration of added Maillard&amp;#x27;s reactants (glucose and l-lysine) were freeze dried, further desiccated (P2O5) to `zero&amp;#x27; % moisture, and heated for 48h at 90°C. Under these conditions, all model systems were well below their measured glass transition temperature (Tg). Skim-milk powder samples (1.7 and 3.9%

Future Prospects

IUPAC Standards Online

IUPAC Standards Online

Experiences on the creation of a specialization career in Industrial Biotechnology: a case of synergistic interaction between academic and industry – oriented institutions

The proposal was originated in 2007 from an agreement between two Argentine institutions, the Sch... more The proposal was originated in 2007 from an agreement between two Argentine institutions, the School of Exact and Natural Sciences (FCEyN, University of Buenos Aires) and the National Institute of Industrial Technology (INTI), with the aim of contributing to the formation of human resources with competences in biotechnology-based industries. Professionals who work in the design and operation of bioprocesses are formed either in Schools of Sciences or in Engineering, with scarce specific orientation on the different areas relevant to bioprocesses. On the other side, even if several graduate and post-graduate careers in Biotechnology exist in Argentina, most of them are strongly oriented to molecular biology, and generally centered on the research-generated offer, not on the industrial application or demanded production at the industrial scale. Thus, there is a lack of human resources with skills in the several requirements demanded by the “changing frontiers” biotechnology industrie...

Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes

Food Chemistry, 2002

The objective was to study the remaining activity of the enzyme β-galactosidase in dehydrated dai... more The objective was to study the remaining activity of the enzyme β-galactosidase in dehydrated dairy systems and its relationship with simultaneous chemical (i.e. non-enzymatic browning, NEB) and physical changes (structural collapse) at temperatures from 70 to 105 °C. The presence of milk proteins had a structure-stabilizing effect, which was not reflected by enzymic stabilization or NEB prevention. Although the remaining enzyme

Toasting Time and Cooking Formulation Affect Browning Reaction Products Development in Corn Flakes

by Pilar Buera and Abel Farroni

Cereal Chemistry Journal, 2016

During toasting, the last stage of corn flake production, Maillard reaction takes place, favored ... more During toasting, the last stage of corn flake production, Maillard reaction takes place, favored by the high temperature and low water content. The cooking formulation ingredients influence color and flavor of the final product and, therefore, consumer acceptance. However, some undesirable components are also formed. The impact of cooking formulation and toasting time on color development and on the formation of chemical markers was investigated. Samples (flakes) were equilibrated at water activity (aw) 0.8 and toasted at 230°C. After extraction of fluorescent pigments with pronase, fluorescence, absorbance at 420 nm, and furfurals analysis was performed. Sucrose showed a synergistic interaction with malt and salt. Formulation highly affected the amount of 5-hydroxymethylfurfural and furfural formed. L* and a* were sensitive variables to measure overall browning reaction. These results allow for further understanding of the influence of formulation used during cooking and would help to mitigate the formation of undesirable compounds.

Detection of quinoa flour adulteration by means of FT-MIR spectroscopy combined with chemometric methods

Food Chemistry, Feb 1, 2019

Quinoa flour has been receiving an increasing attention as a substitute for wheat flour in bread ... more Quinoa flour has been receiving an increasing attention as a substitute for wheat flour in bread formulations due to immuno-nutritional features. This growing interest in quinoa has increased the demand and consequently the prices, being a target for possible adulterations with cheaper cereals. Fourier transform Mid-infrared spectroscopy (FT-MIR) was used in the present work as a fingerprinting technique to detect the presence of three adulterants (soybean, maize and wheat flours). Partial least squares discriminant analysis (PLS-DA) and soft independent modelling of class analogy (SIMCA) models were used to classify pure from adulterated samples. 414 samples were measured, including pure quinoa flour, pure adulterant flours and adulterated quinoa flours using three different proportions (10, 5 and 1% w/w). PLS-DA showed better classification results than SIMCA, with error rates from 2 to 8% for the three strategies used to detect the presence of adulterants.

Efecto de la formulación y las condiciones de procesamiento sobre el desarrollo del pardeamiento no enzimático y la estabilidad de carotenoides en copos de maíz

Biolatto, Andrea, Guidi, Silvina, Nanni, Mariana y Troilo, Liliana (Comps.). (2018). Desarrollo Tecnológicos en el marco del Programa Nacional de Agroindustria y Agregado de Valor. - 1a. ed. - [s.l] : Ediciones INTA. [s.p.], Aug 1, 2018

El proceso de producción dc copos de malz por laminación comprende las etapas de cocción al vapor... more El proceso de producción dc copos de malz por laminación comprende las etapas de cocción al vapor, atemperado, laminado y tostado. Durante la cocción)' además en el tostado, ocurre la reacción de Maillard! favorecida por las elevadas temperaturas y el bajo contenido de agua en este último paso. Además, se produce la pérdida de compuestos de interés. como los carotenoides. Los diferentes ingredientes que constituyen la fonnulación de los copos de malz influyen sobre el color)' eljlavor del producto final y, por lo tanto. sobre la aceptación por parte de los consumidores. Sin embargo. en el proceso también se forman ciertos compuestos indeseables. Por lo tanto. es importante evaluar cl papel de la formulación)' del tiempo de lOstado en el desarrollo de color y la formación de marcadores químicos. Los copos de maíz se equilibraron a OM' 0.8 Y tostaron a 230°C. Luego de la extracción de pigmentos Ouorcscentes con pronasa se rc..'llizaron análisis de fluoresccncia., absorbancia a 420 nm, coordenadas de color y contenido de furfurales. Por otro lado. se evaluó la estabilidad de los carotenoides en las distintas etapas del proceso de elaboración. Respecto a la formulación. la sacarosa mostró un efecto sinérgico con la sal y la malta para acelerar la reacción de Maillard. La formulación afectó significativamente la cantidad de HMF y furfural formados. Los parámetros cromáticos Lt. y 0* fueron variables adecuadas para evaluar reacción de pardeamiento. Durante el proceso de cocción sc-perdió un 60% de lutcína y un 40% dc 7.eaxantina. Lucgo dcl tostado. la ctapa final. el porcentaje de pérdida de ambos compuestos fuc del 80%. Estos resultados permiten profundizar en el conocimiento de las reacciones que ocurren durante el procesamiento de los cereales. para poder definir las condiciones que disminuyan la generación de compuestos indeseables y la mayor retención de las sustancias de interés. Palabras clave: maiz. furfurales, fluorescencia. color, carotenoides Corn flakes produetion ineludes 1bur stages: steam cooking, drying. lamination and toasting. During steam cooking and toasting stagcs. Maillard reaclion takcs place. enhanced by the high tempcrature and the low water contenl. Morcovcr, sorne componcnts of interest are 1051. such as carolenoids. The difTerent ingredients that constitute the com flake formulation innuence color and navor 01' the final product ando thercfore, on consumer acceptancc. However, during processing. certain undesirable compounds are al so formcd. Thus. it is important to cvaluatc the importance of the ingrcdients and toasting timc on the color development and the formation 01' chemical markers. Coro llakes weTe equilibrated at 0li-0.8 and toasted at 230°C. After fluorescent pigmcnts extraction with pronase, l1uorcscencc, absorbance al 420 nm. color coordinates and furfurals content analysis ""ere perfomlcd. On the other hand. the stability of carolenoids during the difTerent stages of elabol'ation was analyzed. Regarding lhe formulation. sucrose showed a synergistic effect with salt and malt, enhancing the Maillard reaetion. Formulation signHicantly affected the amollnt of HMF and furfurals formed. Chromatic paramctcrs L * and 0* were-proper variables evaluated in relation with the browning reaction. During cooking. 60% of lutcin and 40% of 7.caxanthin \Vere lost. Aftcr toasting. the final stagc, the pcrccntage of loss was 80% for both compounds. These results allow furthcr understanding of the rcactions that take place during cereal processing, in order to define lhe best conditions to deerease the formation of undesirable compounds and the highest retention of substances of interest.

Multi-analytical Approach to Oxidative Stability of Unrefined Argan, Chia, Rosa Mosqueta and Olive Oils

Journal of Nutrition & Food Sciences, 2016

Fresh, unrefined argan (AR), chia (CH), rosa mosqueta (RM) and olive (OL) oils were evaluated for... more Fresh, unrefined argan (AR), chia (CH), rosa mosqueta (RM) and olive (OL) oils were evaluated for thermal stability with dielectric spectroscopy, differential scanning calorimetry, peroxide values (PV) and free fatty acids (FFAs). The dielectric constant ('), dielectric loss (''), and melting temperature (T m ) of the oils correlated with degree of unsaturation, with the highest static dielectric constant (εs') for CH oil (3.311), the most unsaturated. AR and CH oils showed the highest electrical conductivities at 500 Hz (505, 230 pS/m, respectively), and CH and RM oils the lowest T m (-41.0, -36.6°C, respectively). All oils stored at 65°C for 432 hr showed minor changes in εs'. After 180°C for 28 h, εs' and ε'' increased from 5% to 7%. Initial PVs of these oils were <3.7 mmol O 2 /kg, and for highly unsaturated CH oil this increased to 221 mmol O 2 /kg after 65°C for 432 hr. At 180°C, the FFAs increased in all oils, except AR oil. Oxidation onset temperature of the oils correlated with PVs after 65°C for 432 h (r=-0.91) and with FFAs and εs' after 180°C for 28 hr (r=-0.81, -0.83, respectively).

Solubility, sorption isotherms and thermodynamic parameters of β-cyclodextrin complexes with poplar propolis components: Practical implicances

LWT

Thermal transitions and enthalpic relaxations as related to the stability of microencapsulated paprika powders

Journal of Food Engineering, 2019

Present work investigates the effect of thermal transitions and enthalpy relaxation phenomenon on... more Present work investigates the effect of thermal transitions and enthalpy relaxation phenomenon on the physico-chemical stability of paprika microencapsulated powders. Wall materials were combinations of soy protein isolates, maltodextrin and gum arabic. Powders stability was evaluated through the solid-water interactions, determined by sorption kinetics, calorimetry and color changes. The water sorption isotherms were well described by the GAB model. Below the critical condition, a w 0.6 and water content 11 % (d. b.) the systems were in amorphous state at 25 °C, and enthalpy relaxations were detectable as endothermal events in the stored samples. The magnitude of the enthalpy relaxations increased with storage temperature below T g and with time of storage. In the amorphous microencapsulates, luminosity changes measured as (L o *-L*) values decreased as a function of time and a w , indicating pigment decoloration. The kinetics of the enthalpy relaxations changes, instead of the punctual values of the variables under study, were related to the dynamics of deteriorative changes. It can be concluded that enthalpy relaxation phenomenon can be established as a criterion for defining storage conditions or predict changes in microencapsulated and other systems that have to be stored in the glassy state. Highlights Kinetics of encapsulated paprika discoloration were related to enthalpy relaxations. Changes in glassy state can be related to enthalpy relaxation phenomenon. Enthalpy relaxations can serve for predicting changes in glassy state.

Crystallization kinetics of lactose in sytems co-lyofilized with trehalose. Analysis by differential scanning calorimetry

Food Research International, 2001

The objective of the present work was to study by differential scanning calorimetry phase/state t... more The objective of the present work was to study by differential scanning calorimetry phase/state transitions in model systems of amorphous lactose and lactose co-lyophilized with trehalose. The obtained parameters, such as glass transition temperatures (T g) and enthalpies of crystallization were employed to test the applicability of different proposed models to predict the behavior of these systems. Thermograms of low moisture lactose-trehalose mixtures showed only one glass transition temperature indicating that compatibility exists between both sugars. The increase of trehalose concentration in the mixture promoted a delay of lactose crystallization in isothermal runs, and of the crystallization temperature (T cr) in dynamic experiments. The presence of trehalose delayed lactose crystallization, without affecting the T g value. Several factors (thermodynamic, geometric, kinetics) may modify the molecular environment in the combined systems, affecting nucleation and/or crystal growth. Three models [Arrhenius, Williams-Landel-Ferry (WLF) and Vogel-Tamman-Fulcher (VTF)] were used to study the temperature dependence of the crystallization time. Although experimental points were fitted fairly well by all these models in the range of temperature from 14 to 59 C above T g value, the VTF equation appears to apply better for sugars.

Food Color and Appearance Food Appearance and Expectations J. B. Hutchings, M. R. Luo, and W. Ji ... more Food Color and Appearance Food Appearance and Expectations J. B. Hutchings, M. R. Luo, and W. Ji Color and Visual Appearance in Foods R. D. Lozano Colors Seen through Transparent Objects O. Da Pos and C. Rao What Is the Color of a Glass of Wine? I. Jung, P. Jokela, P. Brandt, and O. Victor Color as a Code in Food Packaging: An Argentine Case M. L. Musso Effect of Illuminance and Correlated Color Temperature on Visibility of Food Color in Making Meals S. Okuda , Y. Fukumoto, N. Hara , H. Iwade, and W. Iwai Effect of Hydrothermal Conditions on Translucence of Milled Rice M. O. Bello, R. J. Aguerre, M. P. Tolaba, and C. Suarez Measuring Banana Appearance Aspects Using Spectrophotometer and Digital Camera W. Ji, M. R. Luo, and J. B. Hutchings Food Colorimetry and Color Scales Is the Color Measured in Food the Color That We See? A. I. Negueruela Whiteness, Yellowness, and Browning in Food Colorimetry: A Critical Review R. Hirschler Color Classification of Veal Carcasses: Past, Present, and Future M. l Lucassen, J. Alferdinck, and R. Van Megen Application of Image Analysis to the Color-Phenolic Composition Relationships of Grape Seeds F. J. Rodriguez-Pulido, F. J. Heredia, J. M. Zaldivar -Cruz, and M. L. Gonzalez-Miret Sensing Chlorophyll, Carotenoids, and Anthocyanins Concentrations in Leaves with Spatial Resolution from Digital Image G. Cordon and M. G. Lagorio Color of Honeys from the Southwestern Pampas Region: Relationship between the Pfund Color Scale and CIELAB Coordinates L. M. Gallez, A. Marconi, E. Tourn, M. L. Gonzalez-Miret, and F. J. Heredia Influence of Different Backgrounds on the Instrumental Color Specification of Orange Juices C. M. Stinco, R. Fernandez-Vazquez, A. J. Melendez-Martinez, F. J. Heredia, E. Bejines Mejias, and I. M. Vicario Color Change as Quality Index of Food Color Determination in Dehydrated Fruits: Image Analysis and Photocolorimetry L. M. Agudelo Laverde, N. Acevedo, C. Schebor, and M. P. Buera Color Study at Storage of Lyophilized Carrot Systems A. V. Gallo, M. P. Buera, and C. Petriella Temperature Abuses during Lettuce Postharvest: Impact on Color and Chlorophyll M. V. Aguero, A. E. Bevilacqua, and S. I. Roura Changes in Color and Anthocyanin Content of Different Dried Products Based on Sweet Cherries L. Franceschinis, C. Schebor, and D. M. Salvatori Color Measurement of Nova Mandarins Submitted to Heat and Degreening Treatments during Long Storage S. Guidi, A. M. Sancho, G. Polenta, G. Meier , D. Vazquez, and C. Gonzalez Color of Vacuum-Packed Squid (Illex argentinus) Mantle Rings Treated with Gamma Radiation A. Tomac and M. I. Yeannes Evaluation of Blueberry Color during Storage by Image Analysis S. Matiacevich, P. Silva, F. Osorio, and J. Enrione Effect of Washing-Disinfection Conditions on Total Anthocyanin Retention and Color of Fresh-Cut Strawberries F. Van de Velde, M. Pirovani, D. Guemes, and A. Piagentini Effects of Postharvest Treatments in Ruby Red Grapefruit Quality A. M. Sancho, S. Guidi, A. Biolatto, A. Pazos, and G. M. Grigioni Color Variation in Nut Kernels During Storage under Different Drying Methods L. Pilatti, A. M. Sancho, M. Irurueta, and G. M. Grigioni Kinetics of Melanosis in Shrimp: Effect of Pretreatment Using Chemical Additives M. A. Loubes, C. A. Almada, and M. P. Tolaba Color of Dried Pears as Affected by Prior Blanching and Sugar Infusion S. B. Maidana, M. B. Vullioud, and D. M. Salvatori Color Changes in Fresh-Cut Fruits as Affected by Cultivar, Chemical Treatment, and Storage Time and Temperature A. Piagentini, L. Martin, C. Bernardi, D. Guemes, and M. Pirovani Cross-Sectional Color Evaluation in Borage Stems G. Alcuson, A. M. Ruiz De Castro, M. C. Urzola, R. Oria, and A. I. Negueruela Color as an Index of Food Composition and Properties Spectral Signatures: A Way to Identify Species and Conditions of Vegetables J. D. Sandoval , S. R. Gor, J. Ramallo, A. Sfer, E. Colombo, M. Vilaseca, and J. Pujol Control of Animal Stress and Welfare with Measurements of Skin Color Variation: A New Field of Applications of Colorimetry in Applied Psychology P. F. M. Conceicao Relationship between Mineral Content and Color in Honeys from Two Ecological Regions in Argentina G. P. Balbarrey , A. Andrada , J. Echazarreta, D. Iaconis, and L. M. Gallez Importance of Anthocyanic Copigmentation on the Color Expression of Red Wine in Warm Climate B. Gordillo, M. L.Gonzalez-Miret, and F. J. Heredia Color-Composition Relationships of Seeds from Red Grape Varieties M. J. Jara-Palacios, J. M. Zaldivar-Cruz, F. J. Rodriguez-Pulido, D. Hernanz, F. J. Heredia, and M. L. Escudero-Gilete Color as an Indicator for the Maillard Reaction at Mild Temperatures: The Effect of Reducing Sugars G. Leiva , L. Guida, G. Naranjo, and L. Malec Statistical Relationships between Soil Color and Some Factors of Soil Formation A. Marques-Mateu, S. Ibanez, H. Moreno, J. M. Gisbert, S. Balasch, and M. Aguilar Color Characteristics of Raw Milk from Silage and Alfalfa-Fed Cows L. Langman, L.…

Appli cations in food science ’

Cyclodextrins (CDs) are cyclic oligosaccharides composed of linked glucopyranose subunits. The ma... more Cyclodextrins (CDs) are cyclic oligosaccharides composed of linked glucopyranose subunits. The main property of CDs is that their hydrophobic inner cavity forms inclusion complexes with a wide range of guest molecules, while the hydrophilic exterior enhances CD solubility in water. Because of their molecular inclusion capability, the properties of the materials with which they complex can be significantly modified. Particularly, solubility and stability of bioactive compounds to be used as nutraceuticals, could be improved by encapsulation in CDs. The available thermodynamic data are consistent with an exothermic and spontaneous inclusion processes. Phase solubility studies in liquid systems along with studies of physical properties of solids complex, help to elucidate complex stoichiometry and guest-CD interactions. The use of CD-complexes for improving molecules solubility and stability, for control release and as adjuvant in extraction processes, represents a promising innovative...

Toasting Time and Cooking Formulation Affect Browning Reaction Products Development in Corn Flakes

Cereal Chemistry Journal, 2016

Cereal Chem. 94(3):380-384 During toasting, the last stage of corn flake production, Maillard rea... more Cereal Chem. 94(3):380-384 During toasting, the last stage of corn flake production, Maillard reaction takes place, favored by the high temperature and low water content. The cooking formulation ingredients influence color and flavor of the final product and, therefore, consumer acceptance. However, some undesirable components are also formed. The impact of cooking formulation and toasting time on color development and on the formation of chemical markers was investigated. Samples (flakes) were equilibrated at water activity (a w) 0.8 and toasted at 230°C. After extraction of fluorescent pigments with pronase, fluorescence, absorbance at 420 nm, and furfurals analysis was performed. Sucrose showed a synergistic interaction with malt and salt. Formulation highly affected the amount of 5-hydroxymethylfurfural and furfural formed. L* and a* were sensitive variables to measure overall browning reaction. These results allow for further understanding of the influence of formulation used during cooking and would help to mitigate the formation of undesirable compounds.

Sucrose hydrolysis in a glassy starch matrix

LWT - Food Science and Technology, 1995

ABSTRACT The purpose of present work was to investigate whether the glassy state may prevent sucr... more ABSTRACT The purpose of present work was to investigate whether the glassy state may prevent sucrose inversion in an acid-containing amorphous starch powder (native or pre-gelatinized). It was found that sucrose hydrolysis occurred to a significant extent in the glassy state (in both native and gelatinized starch). Moisture content of the system affected the extent of sucrose hydrolysis but its effect was not attributable to the plasticizing effect of water. Little reaction occurred at moisture contents below the so-called B.E.T. monolayer. Temperature was a critical factor controlling sucrose inversion.

Effect of glass transition on rates of nonenzymic browning in food systems

Journal of Agricultural and Food Chemistry, 1992

Department of Food Science and Center for Advanced Food Technology, Rutgers University, PO Box 23... more

Retention of β-galactosidase activity as related to Maillard reaction, lactose crystallization, collapse and glass transition in low moisture whey systems

International Dairy Journal, 2004

Retention of b-galactosidase activity was analyzed in whey model systems in relation to browning ... more Retention of b-galactosidase activity was analyzed in whey model systems in relation to browning development and physical characteristics of the matrix (degree of matrix compression, crystallinity, glass transition). Amorphous systems were obtained by freeze-drying solutions containing b-galactosidase and reduced lactose milk whey, with or without maltodextrin. Samples (porous or previously compressed) were exposed to atmospheres of relative humidities of 0%, 22% or 44% and stored at 70 C. Remaining enzymatic activity and color development were determined at selected time intervals. The decrease of enzyme activity was simultaneous to browning development, which was in turn accelerated in the low porosity samples and affected by the glass transition of the systems and lactose crystallization. The addition of maltodextrin improved retention of enzyme activity and delayed both browning development and lactose crystallization.

A study of acid-catalyzed sucrose hydrolysis in an amorphous polymeric matrix at reduced moisture contents

Food Research International, 1995

The changes in viscosity and mobility which take place in the proximity of the glass transition a... more The changes in viscosity and mobility which take place in the proximity of the glass transition affect the physical stability of amorphous foods and could also affect the rate of chemical reactions. The effect of glass transition on the rate of acid-catalyzed sucrose hydrolysis was investigated in an amorphous polymeric matrix of polyvinylpyrrolidone (PVP). Aqueous solutions of PVP-sucrose in a citrate buffer were freeze-dried in order to obtain the amorphous matrix. Samples were then equilibrated to several relative humidities and stored at several temperatures. The difference between the glass transition temperature (T,) and the storage temperature (T), T-T,, was not a key factor determining the rate of sucrose hydrolysis, which was controlled by the water content of the system. The major effect on the rate of hydrolysis was related to changes in pH which occur when the system is dehydrated. Knowledge of the actual pH of a system, and the possible changes that may occur during concentration/drying are necessary for a better understanding of chemical changes in low and intermediate moisture foods.

Effect of physical changes on the rates of nonenzymic browning and related reactions

Food Chemistry, 1995

Nonenzymic browning (NEB) due to reaction of D-XylOSe and L-lysine was studied in a dehydrated ma... more Nonenzymic browning (NEB) due to reaction of D-XylOSe and L-lysine was studied in a dehydrated matrix based on poly(vinylpyrrolidone) (PVP) of different average molecular weights. Physical changes (collapse) and NEB were studied temperatures (T) and moisture contents resulting in different values of (T-T,), where TB is the glass transition temperature. Nonenzymic browning rates at low and intermediate moisture contents in a polymeric matrix above its glass transit@ were shown to be closely related to (T-T,). The initially porous matrices underwent a time-dependent shrinkage (collapse) above Tg and this shrinkage increased the rate of browning, presumably by minimizing diffusion paths for reactants. When the reactants (xylose and lysine in PVP) were separated by a reactantfree layer of PVP, the reaction rate decreased as the thickness of the empty layer increased. A lag time was observed, which was directly related to the thickness of this layer.

Color formation due to non-enzymatic browning in amorphous, glassy, anhydrous, model systems

Food Chemistry, 1999

Polymeric matrix model systems (gelatinized starch, maltodextrin and polyvinylpyrrolidone (PVP) M... more Polymeric matrix model systems (gelatinized starch, maltodextrin and polyvinylpyrrolidone (PVP) MW 40 000) containing a low concentration of added Maillard&amp;#x27;s reactants (glucose and l-lysine) were freeze dried, further desiccated (P2O5) to `zero&amp;#x27; % moisture, and heated for 48h at 90°C. Under these conditions, all model systems were well below their measured glass transition temperature (Tg). Skim-milk powder samples (1.7 and 3.9%

Future Prospects

IUPAC Standards Online

IUPAC Standards Online

Experiences on the creation of a specialization career in Industrial Biotechnology: a case of synergistic interaction between academic and industry – oriented institutions

The proposal was originated in 2007 from an agreement between two Argentine institutions, the Sch... more The proposal was originated in 2007 from an agreement between two Argentine institutions, the School of Exact and Natural Sciences (FCEyN, University of Buenos Aires) and the National Institute of Industrial Technology (INTI), with the aim of contributing to the formation of human resources with competences in biotechnology-based industries. Professionals who work in the design and operation of bioprocesses are formed either in Schools of Sciences or in Engineering, with scarce specific orientation on the different areas relevant to bioprocesses. On the other side, even if several graduate and post-graduate careers in Biotechnology exist in Argentina, most of them are strongly oriented to molecular biology, and generally centered on the research-generated offer, not on the industrial application or demanded production at the industrial scale. Thus, there is a lack of human resources with skills in the several requirements demanded by the “changing frontiers” biotechnology industrie...

Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes

Food Chemistry, 2002

The objective was to study the remaining activity of the enzyme β-galactosidase in dehydrated dai... more The objective was to study the remaining activity of the enzyme β-galactosidase in dehydrated dairy systems and its relationship with simultaneous chemical (i.e. non-enzymatic browning, NEB) and physical changes (structural collapse) at temperatures from 70 to 105 °C. The presence of milk proteins had a structure-stabilizing effect, which was not reflected by enzymic stabilization or NEB prevention. Although the remaining enzyme

Toasting Time and Cooking Formulation Affect Browning Reaction Products Development in Corn Flakes

by Pilar Buera and Abel Farroni

Cereal Chemistry Journal, 2016

During toasting, the last stage of corn flake production, Maillard reaction takes place, favored ... more During toasting, the last stage of corn flake production, Maillard reaction takes place, favored by the high temperature and low water content. The cooking formulation ingredients influence color and flavor of the final product and, therefore, consumer acceptance. However, some undesirable components are also formed. The impact of cooking formulation and toasting time on color development and on the formation of chemical markers was investigated. Samples (flakes) were equilibrated at water activity (aw) 0.8 and toasted at 230°C. After extraction of fluorescent pigments with pronase, fluorescence, absorbance at 420 nm, and furfurals analysis was performed. Sucrose showed a synergistic interaction with malt and salt. Formulation highly affected the amount of 5-hydroxymethylfurfural and furfural formed. L* and a* were sensitive variables to measure overall browning reaction. These results allow for further understanding of the influence of formulation used during cooking and would help to mitigate the formation of undesirable compounds.