Towards an improved calorimetric methodology for glass transition temperature determination in amorphous sugars

Saavedra-Leos, María Zenaida; Álvarez-Salas, Claudia; Esneider-Alcalá, Miguel; Toxqui-Terán, Alberto; Pérez‐García, Sergio Alfonso; Ruiz-Cabrera, M.A.

doi:10.1080/19476337.2011.639960

Cited by 38 publications

(23 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Thus, the total sugar content was employed to calculate the theoretical T g value of the fruit juices, employing the Scheffe's cubic model according to Equation (1). Based on this equation, the calculated theoretical T gJ value for the OJ prepared in this work was 41.48°C, which was very close to the value of 46.2°C, determined experimentally by Saavedra-Leos et al (2012). Although the use of an additive method for sugarrich systems may be considered inaccurate, the result showed a good approximation to the experimental value, with a difference lower than 10%.…”

Section: Setting the Spray Drying Conditions Based On The T G Of The supporting

confidence: 57%

“…However, the drying of sugar-rich food products such as fruit juices is not a trivial task because of the high water content, low molecular weight species and the low glass transition temperatures of the individual components of juice (Jakubczyk, Ostrowska, & Gondek, 2010;Karaaslan & Dalgıç, 2014). The glass transition temperature (T g ) is a transition dependent on time and comprises the change in any direction from the vitreous state into the rubbery state of a substance subjected to changes in temperature or humidity (Saavedra-Leos et al, 2012;Van Sleeuwen, Zhang, & Normand, 2012).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Obtaining orange juice–maltodextrin powders without structure collapse based on the glass transition temperature and degree of polymerization

Saavedra-Leos

Leyva‐Porras

Álvarez-Salas

et al. 2017

CyTA - Journal of Food

View full text Add to dashboard Cite

Urizar (2018) Obtaining orange juice-maltodextrin powders without structure collapse based on the glass transition temperature and degree of polymerization, CyTA -Journal of Food, 16:1, 61-69, DOI: 10.1080/19476337.2017 To link to this article: https://doi.org/10. 1080/19476337.2017 A set of four maltodextrins (MXs) with different degree of polymerization were employed as carrying agents for the spray drying of liquid orange juice (OJ) without collapse in the microstructure; this was visually observed as fine powders non-agglomerated were obtained with a characteristic color. The powders were subjected to water adsorption and characterized. The effect of the MX added was the increase in the adsorption of water and the subsequent depression in the glass transition temperature (T g ). The microstructure did not crystalize at any water activity, but the phase changed from an amorphous solid to a solid covered by saturated liquid. Additionally, a simple mathematical model based on the molar fractions and the T g of the individual components was proposed for predicting the overall T g of the ternary system water-OJ-MX. The results presented herein may contribute to the processing of sugar-rich systems and in the stability of food products.Obtención de polvos de jugo de naranja-maltodextrina sin colapso estructural basado en la temperatura de transición vítrea y grado de polimerización RESUMEN Se emplearon cuatro maltodextrinas (MX) con diferente grado de polimerización (GP) como agente acarreador para el secado por aspersión sin colapso de la microestructura de jugo de naranja líquido (OJ); esto fue observado visualmente como un polvo de color blanco y apariencia fina sin aglomeración. Los polvos fueron sometidos a un proceso de adsorción de agua y caracterizados. El efecto de la adición de la MX fue el incremento en la adsorción de agua y la subsecuente depresión en el valor de la temperatura de transición vítrea (T g ). Para todas las actividades de agua evaluadas la microestructura no cristalizó, pero la fase cambió de un sólido amorfo a un sólido cubierto por líquido saturado. Adicionalmente se propuso para la predicción del valor de T g del sistema ternario agua-OJ-MX, el uso de un modelo matemático simple basado en las fracciones molares y los valores de T g de los componentes individuales. Los resultados obtenidos pueden contribuir para el procesamiento de sistemas ricos en azúcares y en la estabilidad de productos alimenticios. ARTICLE HISTORY

show abstract

Section: Setting the Spray Drying Conditions Based On The T G Of The supporting

confidence: 57%

Section: Introductionmentioning

confidence: 99%

Obtaining orange juice–maltodextrin powders without structure collapse based on the glass transition temperature and degree of polymerization

Saavedra-Leos

Leyva‐Porras

Álvarez-Salas

et al. 2017

CyTA - Journal of Food

View full text Add to dashboard Cite

show abstract

“…The study of phase transitions has a large impact on different fields such as the food industry, pharmaceutical industry, and polymers. In food products, Saavedra-Leos et al [13] suggested that Tg is a useful indicator for understanding the mechanism of food processing and for predicting the life of food products during storage. Ronkart [14] observed the plasticizer effect of water in food products, which is the major component in the product and is responsible for the depression in Tg.…”

Section: Phase Transitionsmentioning

confidence: 99%

Application of Differential Scanning Calorimetry (DSC) and Modulated Differential Scanning Calorimetry (MDSC) in Food and Drug Industries

et al. 2019

View full text Add to dashboard Cite

Phase transition issues in the field of foods and drugs have significantly influenced these industries and consequently attracted the attention of scientists and engineers. The study of thermodynamic parameters such as the glass transition temperature (Tg), melting temperature (Tm), crystallization temperature (Tc), enthalpy (H), and heat capacity (Cp) may provide important information that can be used in the development of new products and improvement of those already in the market. The techniques most commonly employed for characterizing phase transitions are thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), thermomechanical analysis (TMA), and differential scanning calorimetry (DSC). Among these techniques, DSC is preferred because it allows the detection of transitions in a wide range of temperatures (−90 to 550 °C) and ease in the quantitative and qualitative analysis of the transitions. However, the standard DSC still presents some limitations that may reduce the accuracy and precision of measurements. The modulated differential scanning calorimetry (MDSC) has overcome some of these issues by employing sinusoidally modulated heating rates, which are used to determine the heat capacity. Another variant of the MDSC is the supercooling MDSC (SMDSC). SMDSC allows the detection of more complex thermal events such as solid–solid (Ts-s) transitions, liquid–liquid (Tl-l) transitions, and vitrification and devitrification temperatures (Tv and Tdv, respectively), which are typically found at the supercooling temperatures (Tco). The main advantage of MDSC relies on the accurate detection of complex transitions and the possibility of distinguishing reversible events (dependent on the heat capacity) from non-reversible events (dependent on kinetics).

show abstract

“…Furthermore, the CNC2 samples showed a new degradation step at 190–230 °C, which could be related to the degradation of low molecular weight sugar compounds, suggesting that the chemical treatment conditions used for CNC2 could depolymerize the cellulose chains into sugars. In the literature, it was observed that the maximum decomposition temperature of glucose was in the range of 215–224 °C . Mandal and Chakrabarty isolated CNC from sugarcane bagasse with 60 wt % sulfuric acid for 5 h at 50 °C.…”

Section: Resultsmentioning

confidence: 99%

Office waste paper as cellulose nanocrystal source

Orue

Santamaria‐Echart

Eceiza

et al. 2017

J of Applied Polymer Sci

View full text Add to dashboard Cite

Cellulose nanocrystals (CNC) are isolated from office waste paper using an alkali solution and a subsequent acid hydrolysis process. The Fourier transform infrared spectroscopy and X-ray diffraction (XRD) results demonstrate that ink and fillers used in the papermaking industry are almost totally removed after alkali treatments. The XRD results show that CNCs obtained after 2 wt % NaOH solution treatment and a subsequent hydrolysis process exhibit only a cellulose I crystalline structure, and the crystallinity index value increases around 42% with respect to initial office waste paper. Nevertheless, CNCs obtained after 7.5 wt % NaOH solution treatment and a subsequent acid hydrolysis process show a mixture of cellulose I and cellulose II polymorphs. The thermal analysis shows that the CNCs obtained after 7.5 wt % NaOH solution treatment and a subsequent acid hydrolysis process are thermally less stable than other samples, suggesting that the cellulose chains could depolymerize into low molecular weight sugar compounds. Even though the atomic force microscopy images confirm the presence of CNCs, the optical images show that some cellulose microfibers still maintain their structure.

show abstract

Towards an improved calorimetric methodology for glass transition temperature determination in amorphous sugars

Cited by 38 publications

References 27 publications

Obtaining orange juice–maltodextrin powders without structure collapse based on the glass transition temperature and degree of polymerization

Obtaining orange juice–maltodextrin powders without structure collapse based on the glass transition temperature and degree of polymerization

Application of Differential Scanning Calorimetry (DSC) and Modulated Differential Scanning Calorimetry (MDSC) in Food and Drug Industries

Office waste paper as cellulose nanocrystal source

Contact Info

Product

Resources

About