Characterization of Pectin-Based Gels: A 1H Nuclear Magnetic Resonance Relaxometry Study

Beira, Maria J.
Öztop, Halil Mecit
Sebastião, Pedro J.
Rare sugars are monosaccharides and their derivatives that are not commonly found in nature. d-Allulose is a rare sugar that is C-3 epimer of fructose and presents an alternative to sucrose with potential health benefits. In this study, different amounts of sucrose, d-allulose, and soy protein isolate (SPI) were used to prepare a set of pectin gels. The effect of these ingredients on the gels was studied at both a molecular level, by 1H nuclear magnetic resonance (NMR) relaxometry, and a macroscopic level, through the assessment of viscoelastic properties as well as hardness and moisture content measurements. The NMR dispersion profiles were analyzed considering relaxation mechanisms associated with rotational and translational diffusion motions of mono- and disaccharides as well as bound water molecules. Significant variations of the local diffusion coefficient for the studied formulations were evidenced by the model fitting analysis. The viscosity trends observed within each group of samples having the same amount of SPI were mostly in agreement with the diffusion coefficients obtained from the NMR relaxometry. The observed discrepancies could be explained considering hardness and moisture content results, which put into evidence the fact that decreasing the moisture (mainly free water) affects the macroscopic properties of the systems, such as hardness and viscosity, but not the local diffusion processes probed by NMR relaxometry. These findings show the importance of combining both micro- and macroscopic information to analyze the different properties of food products.
Journal of Agricultural and Food Chemistry


Physicochemical and NMR relaxometric characterization of freeze and spray dried glycated soy proteins
Taş, Ozan; Öztop, Halil Mecit; Department of Food Engineering (2019)
Rare sugar is a type of a sugar group consisting of monosaccharides that is not widely found in nature as its name implies. D-psicose that is C-3 epimer of fructose is one of the rare sugars, and its sweetness is equivalent to 70% of the sweetness of sucrose. Researches showed that gylcation with sugars improves their physical and chemical properties. In this study, two different glycation techniques were conducted (freeze drying and spray drying) for soy proteins. In addition to D-Psicose, glycation was pe...
Poçan, Pelin; Öztop, Halil Mecit; Mert, Behiç; Department of Food Engineering (2021-8-20)
Confectionary gels are considered as composite gel systems consisting of high amount of sugar and gelling agents such as gelatin or starch. Production of low-calorie soft confectionery products has been the interest of the industry in recent years. D‐allulose is classified as one of the rare sugar; sugars which are found in rare amounts in nature. It is a C‐3 epimer of fructose and has 70% of the sweetness of sucrose with much less caloric value of 0.39 kcal/g compared to common sugars. Utilization of D‐all...
Investigation of physico-chemical properties of soy proteins glycated with d-psicose
Beylikçi, Sermet Can; Öztop, Halil Mecit; Department of Food Engineering (2019)
Proteins are one of the most essential food components that is constantly used by food industry because of their functional properties as well as their nutritional value. Soy protein has become popular among the usable protein resources because of its various functional properties such as foaming, gelling, emulsifying and water holding capacities. However, certain drawbacks of soy protein like limited solubility especially in acidic environment, emerge the need for modification for further use in broader va...
AKIN, EDA; Volkan, Mürvet; Ertaş, Gülay; Department of Chemistry (2022-6-22)
Sialic acids are an important sub-group of nine carbon acidic sugars. Sialic acid plays a significant role in mediating and modulating a variety of physiological activities due to its widespread distribution in human body. Several pathogens and toxins also bind to sialic acid, change its level and signal pathological conditions. The identification and quantification of sialic acid levels are also significant for early detection of many diseases such as breast and colon cancer. In this study, sialic acid de...
Understanding the role ofd-Alluloseand soy protein addition in pectin gels
Ates, Elif Gokcen; ÖZVURAL, EMİN BURÇİN; Öztop, Halil Mecit (Wiley, 2020-09-01)
D-Allulose (a monosaccharide and C3 epimer of fructose), one of the common rare sugars is getting attention due to its low caloric values. In this study, DAllulose was used as a replacement of sucrose at different ratios (D-Allulose/Sucrose: 35/0, 20/15, 10/25, 0/35) to formulate pectin-based soft confectionery gels. Soy protein isolate was also added to increase the protein content. Physical properties, such as hardness, moisture content, pH, and color, were measured for the gels. Higher hardness values we...
Citation Formats
M. J. Beira, H. M. Öztop, and P. J. Sebastião, “Characterization of Pectin-Based Gels: A 1H Nuclear Magnetic Resonance Relaxometry Study,” Journal of Agricultural and Food Chemistry, vol. 69, pp. 12102–12110, 2021, Accessed: 00, 2021. [Online]. Available: