RESUMEN
Three-dimensional polymeric network of hydrogels avoids its dissolution into the aqueous region. Hydrogels must have strong structural integrity to be used for drug/nutraceutical delivery. A three factor-three-level Box-Behnken design was used to understand the effects of starch concentration, NaCl, and pH on the textural and structural integrity of Lysine modified kutki millet starch hydrogels. Various kinetic models were fitted to the time-course measurement of shrinkage behavior of both conventionally (CDHG) and freeze-dried (FDHG) hydrogel. Increasing the swelling temperature (5-50 °C) showed values of higher molecular weight of polymer chains between neighboring crosslinks ( M c ) ¯ (g/mol) for FDHG (9539.59-56,769.72) than CDHG (1096.28-11,420.48). Similarly, mesh size (ξ) was more for FDHG (38.63-109.53 Ȧ) than CDHG (10.97-42.74 Ȧ). However, other network parameters such as polymer volume fraction ( ∅ p ) was lower for FDHG (0.229-0.146) than CDHG (0.3882-0.222). These values suggest low swelling power of CDHG compared to FDHG. Thermodynamically, FDHG took less energy to swell than CDHG. The study showed that FDHG has better properties than CDHG and could be employed in nutraceutical delivery. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05953-x.
RESUMEN
Understanding food materials from the classical realm of physics including soft condensed matter physics has been an area of interest especially in the structural design engineering of food products. The contents of this review would help the reader in understanding the thermodynamics of food polymer, structural design principles, structural hierarchy, steps involved in food structuring, newer structural design technologies, and structure measurement techniques. Understanding the concepts of free volume would help the food engineers and technologists to study the food structural changes, manipulate process parameters and, the optimum amount of nutraceuticals/ingredients to be loaded in the food matrix. Such understanding helps in reducing food ingredient wastage while designing a food product.
RESUMEN
The aim of the study was to quantify sugar profile and rheological behaviour of four Indian honey varieties (Cotton, Coriander, Dalbergia, and Murraya). The effect of temperature (5, 10, 20 and 30 °C) on rheological behaviour of these honey varieties was also studied. Fourteen sugars (three monosaccharides, six disaccharides, four trisaccharides, and one oligosaccharide) were quantified. The concentration of glucose and fructose varied from 33.40-34.06% to 36.86-41.15%, respectively. Result indicated that monosaccharides were the dominant sugars among all the honey samples. Low amounts of turanose, trehalose, melibiose, and raffinose were present in the range of 0.02-0.03%, 0.11-0.26%, 0.09-0.18% and 0.06-0.12%, respectively in the analyzed honey varieties. The rheological behaviour of all four honey varieties was analysed at different temperatures i.e. 5, 10, 20 and 30 °C followed an Arrhenius model. In analysed honey varieties storage modulus (G') was less than loss modulus (Gâ³) which confirmed the Newtonian behaviour of all honey samples.
RESUMEN
Floral authenticity of coriander (Coriandrum sativum) honey samples was confirmed by melissopalynology. Effect of temperature, time and pH on quality parameters i.e. hydroxymethylfurfural (HMF) content, diastase and invertase activity of coriander honey was analysed using response surface methodology. Central composite rotatable design was adopted for optimization of process variables. An increased in HMF content was observed with increase in temperature and pH whereas diastase activity decreased with increase in temperature and with a pH value other than the optimum value of 4.6-5.6. Invertase activity was maximum at 4.8 pH. Interaction effect of temperature and pH was significant for HMF whereas interaction effect of temperature and time was significant for HMF, diastase and invertase activity. Optimization of variables was done by the mathematical method, and optimized values of HMF content, diastase, and invertase activity were obtained as 7.78 (mg/kg), 17.95 DN and 13.96 IN, respectively at 47.5 °C (temperature), 4.7 (pH) and 9 min (time).
RESUMEN
Starch is a biopolymer containing hydrophilic groups and is used in hydrogels preparation. Amino acids are multifunctional monomers of proteins that can be used as a cross linker to modify the starch by incorporating new functional groups into its chains. In this study, the Kutki millet starch was isolated and modified with lysine (positively charged), aspartic acid (negatively charged), and threonine (neutral) at varying pH levels. These modified starches were characterized for their various functional, structural, pasting, and textural properties. Hydrogels prepared from Lys9-KMS, Thr9-KMS, and AA11-KMS, possessing less adhesiveness, strong integrity, and hardness were then characterized for their XRD and morphological characterization. The principal component analysis (PCA) biplot showed that the samples modified at higher pH levels are positively correlated with the textural properties, swelling power and amylose content (I and IV quadrants), than those modified at lower pH. It may be inferred that starch modified with amino acid at higher pH have good textural properties than those at lower pH. Results of the overall investigation indicated that among these three amino acids, lysine could be a better cross linker for modification of Kutki millet starch and preparation of their gels for the delivery of nutraceuticals.