Crystallization and strength analysis of amorphous maltose and maltose/whey protein isolate mixtures

Abstract

BACKGROUND Maltose is an essential derivative of starch. To understand the processability and stability of maltose‐containing foods, material characterization of the phase and state transition from its amorphous state is required. Although the crystallization of amorphous maltose is well understood, few studies have reported the relationship between the crystallization and the glass transition temperature (Tg)‐related molecular mobility. In this study, water sorption, crystallization, Tg‐related α‐relaxation, and the corresponding time factor for amorphous maltose and maltose / whey protein isolate (WPI) mixtures are measured at various water activity (aw) levels and 25 °C. RESULTS The water‐additive principle for maltose / WPI mixtures was observed at aw ≤ 0.440 at the molecular level, whereas the crystallization of amorphous maltose occurred at high aw values (≥0.534). The crystal formation and crystallization kinetics of amorphous maltose were affected by water and WPI at aw ≥ 0.534 and 25 °C, as determined by X‐ray diffraction. The relationship between Tg and the water content was fitted by the Gordon–Taylor model, and its constant showed a compositional dependence for the maltose / WPI mixtures. The α‐relaxation temperature of the amorphous samples decreased due to water plasticization, but increased with an increase in the WPI quantity. The Strength (S) value for amorphous maltose, which was a quantitative estimate of the compositional effects on molecular mobility, was based on the William–Landel–Ferry (WLF) equation. CONCLUSION The S concept exhibits considerable potential for application in controlling the crystallization of amorphous maltose and improving the processability and stability of maltose‐containing foods. © 2020 Society of Chemical Industry

Detection of Authenticity and Quality of the Turkish Delights (Lokum) by Means of Conventional and Fast Field Cycling Nuclear Magnetic Resonance Relaxometry

“…This case also affected the diffraction pattern of these samples. As indicated by Wu et al, native maltose gives a peak at 12.7° . This peak was also observed in our study for all of the samples that contain corn syrup as a result of the existence of maltose residues.…”

“…The aforementioned peak intensity was found to be higher for the SCG40 sample compared to the SCG60 sample. This case could be related to the quantity of the maltose crystal, as mentioned in a previous study . According to this study, an increase in the quantity of maltose crystals resulted in an increase in the intensity of related peaks.…”

“…This incident might stem from the existence of maltose in the formulation of corn syrups, found normally in the amorphous state in its native form. 46 Although similar diffraction patterns were obtained for the corn-syrup-containing samples, there were also small changes. For example, the diffraction pattern of SCG40 and SCG60 samples is very similar, as expected, because these specimens are composed of a similar corn syrup.…”

“…With reference back to the diffraction pattern of the corn-syrup-containing samples, the amorphous halo pattern is more dominant, as seen in Figure . This incident might stem from the existence of maltose in the formulation of corn syrups, found normally in the amorphous state in its native form . Although similar diffraction patterns were obtained for the corn-syrup-containing samples, there were also small changes.…”

Using Carboxymethyl Cellulose as the Additive With Enzyme-Catalyzed Carboxylated Starch to Prepare the Film With Enhanced Mechanical and Hydrophobic Properties

“…Because of its strong hydrophilicity and polarity, carboxylated starch has been widely used in drug carriers, adsorbents, flocculants, and other applications (Shahriarpanah et al, 2016;Sarmah and Karak, 2020). Starch is a polycrystalline polymer composed of crystalline, amorphous, and crystalline transition regions (subcrystalline regions) (Sharmin et al, 2020;Wu et al, 2020;Xiao et al, 2020). The modification of starch mostly occurs in the amorphous area within the surface layer of the granules.…”