Chemical, Thermal and Physical Characterization of Inulin for its Technological Application Based on the Degree of Polymerization

Abstract

In this work was studied the effect of the degree of polymerization (DP) in two systems based on inulin. Understanding the relation between the chemical and physical properties, allows establishing the potential application for inulin according to its DP. Amorphous inulin powders were characterized by mass spectrometry to determine the DP. Inulin from chicory root and dahlia tubers showed a DP of 2–15 and 2–12, respectively. The systems were exposed to different water activities, finding sigmoidal curves type II. Thermal analysis showed two melting events, suggesting the presence of crystals differing in size. The glass transition temperature range widened and lowered in the high DP inulin. By X‐ray diffraction low DP inulin presented a moderate transition behavior while in high DP inulin was conducted abruptly. State diagrams for stability showed that high DP inulin must be stored at more rigorous conditions of temperature and humidity for avoiding unwanted crystallization effects. Practical Applications The results presented in this work are useful for: (i) relating the physical and thermal properties (Tm, Td and Tg) with the degree of polymerization of sugar‐rich systems such as inulin powders, (ii) set the optimal processing conditions in an industrial application such as spray drying process while avoiding product damage, and (iii) predicting the product stability based on the physical properties plotted in the form of a state diagram.

Encapsulation of Active Ingredients in Food Industry by Spray-Drying and Nano Spray-Drying Technologies

“…Ahmed et al [38] investigated the influence of the inlet temperature, feed rate, feed solution concentration, and degree of polymerization (DP) on the physical properties of spray-dried inulin. They found that concentration of the feeding solution affected the crystallinity of the final product i.e., at 40% concentration, a crystalline material was preserved, while at 20%, an amorphous product was obtained.…”

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

“…They also conclude that both carbohydrates polymers were effective as carrying agents during the spray-drying process of blueberry juice; however, maltodextrin showed better performance in terms of the antioxidants conservation. Leyva-Porras et al [30] studied the physicochemical and thermal properties and the effect of degree of polymerization (DP) of inulin. MDSC was employed in order to determine thermal events such as Tm, Tg, and Td.…”

Spray Drying of Blueberry Juice-Maltodextrin Mixtures: Evaluation of Processing Conditions on Content of Resveratrol

“…Saavedra-Leos et al determined an inverse relation between T g and DE of maltodextrins [21]. Through several works reported by the Saavedra-Leos group [14,22,37,38,39], we have observed that in some juices such as orange and blueberries, their physicochemical properties varied with the differences in the type and distribution of molecular weight of the carrier agent. In these studies, we have attributed this behavior mainly to: (i) Differences in the molecular weight distribution of the carrier agent, (ii) the arrangement of polymer chains (i.e., entangled or linear) and (iii) the type of molecule in these chains (for example, glucose for maltodextrin or fructose for inulin).…”

“…All these functional groups are responsible for carrying out molecular chemical interactions such as hydrogen bonding, and Van der Waals interactions. In several works it has been reported that these chemical interactions (inter and intramolecular) are responsible of the adsorption of water on different carrying agents such as inulin and maltodextrins [21,38]. In these works, water adsorption was promoted with increasing the molecular weight of carrying agents.…”