Classification and quantification of sucrose from sugar beet and sugarcane using optical spectroscopy and chemometrics
Hilmi Erikliogl, Esmanur Ilhan, Mikhail Khodasevich, Darya Korolko, Marena Manley, Rosario Castillo, Mecit Halil Oztop
Sucrose, obtained from either sugar beet or sugarcane, is one of the main ingredients used in the food industry. Due to the same molecular structure, chemical methods cannot distinguish sucrose from both sources. More practical and affordable methods would be valuable. Sucrose samples(cane and beet) were collected from nine countries, 25% (w/w) aqueous solutions were prepared and their absorbances recorded from 200 to 1380 nm. Spectral differences were observable in the ultraviolet–visible (UV–Vis) region from 200 to 600 nm due to impurities in sugar. Linear discriminant analysis (LDA), classification and regression trees, and soft independent modeling of class analogy were tested for the UV–Visregion. All methods showed high-performance accuracies. LDA, after selection of five wavelengths, gave 100% correct classification with a simple interpretation. In addition, binary mixtures of the sugar samples were prepared for quantitative analysis by means of partial least squares regression and multiple linear regression (MLR). MLR with first derivative Savitzky–Golay were most acceptable with root mean square error of cross-validation, prediction, and the ratio of (standard error of) prediction to (standard) deviation values of 3.92%, 3.28%, and 9.46, respectively. Using UV–Vis spectra and chemometrics, the results show promise to distinguish between the two different sources of sucrose. An affordable and quick analysis method to differentiate between sugars, produced from either sugar beet or sugarcane, is suggested. This method does not involve complex chemical analysis or high-level experts and can be used in research or by industry to detect the source of the sugar which is important for some countries’ agricultural policies.
KEYWORDS: multivariate data analysis, sucrose, sugar beet, sugarcane, UV–Vis spectroscopy
Application of segmented analysis via multivariate curve resolution with alternating least squares to 1H-nuclear magnetic resonance spectroscopy to identify different sugar sources
Cristian A. Fuentes, Mecit Halil Oztop, Macarena Rojas-Rioseco, Martín Bravo, Aylin Ozgür Goksu, Marena Manley, Rosario del P. Castillo
The different types of sugar employed in the food industry exhibit chemical similarity and are mostly dominated by sucrose. Owing to the sugar origin of and differences in production, the presence of certain minor organic compounds differs. To differentiate between sugars based on their botanical source, geographical origin, or storage conditions, commercial brown sugars and sugar beet extracts were analyzed by 1H NMR spectroscopy applying a segmented analysis by means of multivariate curve resolution-alternating least squares (MCR–ALS). Principal component analysis and partial least squares-discriminant analysis yielded excellent differentiation between sugars from different sources after the application of this preprocessing strategy; without loss of chemical information and with direct interpretation of the results. By applying a segmented analysis via MCR–ALS to 1H NMR sugar data, similar spectroscopic profiles could be differentiated. This improved the selectivity of 1H NMR spectroscopy for sugar source differentiation which can be useful for industrial sugar authentication purposes
KEYWORDS: Sugar beet, Brown sugar, Multivariate analysis, 1H NMR spectroscopy, Preprocessing
Molecular dynamics of jelly candies by means of Nuclear Magnetic Resonance relaxometry
Kruk, Danuta; Grunin, Leonid; Stankiewicz, Aleksandra; Kołodziejski, Karol; İlhan, Esmanur; Oztop, Mecit Halil
1H spin-lattice Nuclear Magnetic Resonance relaxation studies have been performed fordifferent kinds of Haribo jelly and Vidal jelly in a very broad frequency range from 10kHz to 10MHz to get insight into dynamical and structural properties of jelly candies on the molecular level. This extensive data set has been thoroughly analyzed revealing three dynamical processes, referred to as slow, intermediate and fast dynamics occurring on the timescale of 10-6s, 10-7s and 10-8s, respectively. The parameters have been compared for different kinds of jelly for the purpose of revealing their characteristic dynamical and structural properties as well as enquire into how increasing temperature affects these properties. It has been shown that dynamical processes in different kinds of Haribo jelly are similar (this can be treated as a sign of their quality and authenticity) and that the upon temperature mainly the fraction of confined water molecules is reduced. Two groups of Vidal jelly have been identified. For the first one, the parameters (dipolar relaxation constants and correlation times) matches those for Haribo jelly. For the second group included cherry considerable differences in the parameters characterizing their dynamical properties have been revealed.
KEYWORDS: Nuclear Magnetic Resonance, relaxation, dynamics, jelly candies
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Effect of Different Syrup Types on Turkish Delights (Lokum): A TD-NMR Relaxometry Study
Pelin Pocan, Leonid Grunin, and Mecit Halil Oztop
Turkish delights were formulated by using sucrose (control) and different types of corn syrups (having varying glucose/fructose ratios) and allulose syrup. 30% allulose syrup and 30% sucrose-containing Turkish delights were found to exhibit an amorphous structure. Time-domain NMR relaxometry experiments were also conducted on delights by measuring T2 relaxation times, and two distinct proton populations were observed in all formulations. The use of different syrup types at different substitution levels led to significant changes in the relaxation times (T2a and T2b) of the samples, indicating that the relaxation spectrum might be used as a fingerprint for Turkish delights containing different types and amounts of syrup types. Second moment (M2) values which were measured from the signal acquired using a magic sandwich echo pulse sequence were also found to be an effective and promising indicator to detect the crystallinity of Turkish delights.
KEYWORDS: time-domain (TD) NMR relaxometry, magic sandwich echo (MSE), soft candies, food gels, allulose syrup
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The NMR analysis of sugar and sugar including food products can be performed by the following MATLAB file.
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Non-Conventional Time Domain (TD)-NMR Approaches for Food Quality: Case of Gelatin-Based Candies as a Model Food
Sirvan Sultan Uguz, Barıs Ozel, Leonid Grunin, Emin Burcin Ozvural, Mecit Halil Oztop
The TD-NMR technique mostly involves the use of T1 (spin-lattice) and T2 (spin-spin) relaxation times to explain the changes occurring in food systems. However, these relaxation times are affected by many factors and might not always be the best indicators to work with in food-related TD-NMR studies. In this study, the non-conventional TD-NMR approaches of Solid Echo (SE)/Magic Sandwich Echo (MSE) and Spin Diffusion in food systems were used for the first time. Soft confectionary gelatin gels were formulated and conventional (T1) and non-conventional (SE, MSE and Spin Diffusion) TD-NMR experiments were performed. Corn syrups with different glucose/fructose compositions were used to prepare the soft candies. Hardness, °Brix (°Bx), and water activity (aw) measurements were also conducted complementary to NMR experiments. Relaxation times changed (p < 0.05) with respect to syrup type with no obvious trend. SE/MSE experiments were performed to calculate the crystallinity of the samples. Samples prepared with fructose had the lowest crystallinity values (p < 0.05). Spin Diffusion experiments were performed by using Goldman–Shen pulse sequence and the interface thickness (d) was calculated. Interface thickness values showed a wide range of variation (p < 0.05). Results showed that non-conventional NMR approaches had a high potential to be utilized in food systems for quality control purposes.
Keywords: soft candy; gelatin; confectionery; TD-NMR; crystallinity; longitudinal relaxation time; spin diffusion; Magic Sandwich Echo; Solid Echo; second moment
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Investigation of the Hydration Behavior of Different Sugars by Time Domain-NMR
Ozan Tas , Ulku Ertugrul , Leonid Grunin and Mecit Halil Oztop
The hydration behavior of sugars varies from each other and examining the underlying mechanism is challenging. In this study, the hydration behavior of glucose, fructose, allulose (aka rare sugar), and sucrose have been explored using different Time Domain Nuclear Magnetic Resonance (TD-NMR) approaches (relaxation times, self-diffusion, and Magic Sandwich Echo (MSE)). For that purpose, the effects of different sugar concentrations (2.5%, 5%, 10%, 15%, 20%, 30%, and 40%) (w/v) and hydration at different times for 1 day were investigated by T2 relaxation times and self-diffusion coefficients. Crystallinity values of the solid and hydrated sugars were also determined with MSE. Change in T2 relaxation times with concentration showed that the fastest binding with water (parallel with the shortest T2 values) was observed for sucrose for all concentrations followed by glucose, fructose, and allulose. Furthermore, dependency of T2 relaxation times with hydration time showed that sucrose was the fastest in binding with water followed by glucose, fructose, and allulose. The study showed that allulose, one of the most famous rare sugars that is known to be a natural low-calorie sugar alternative, had the lowest interaction with water than the other sugars. TD-NMR was suggested as a practical, quick, and accurate technique to determine the hydration behavior of sugars.
Sugar is an prevalent part of many food with its various functions such as texture, bulkiness, color and act as preservatives . SuChAQuality partner, Middle East Technical University from Turkey, has published an article about the the hydration behavior of different sugars by Time Domain-NMR! Check the article for details!
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Holistic View of Starch Chemistry, Structure and Functionality in Dry Heat-Treated Whole Wheat Kernels and Flour
Jana van Rooyen, Senay Simsek, Samson Adeoye Oyeyinka, Marena Manley
Heat treatment is used as a pre-processing step to beneficially change the starch properties of wheat flour to enhance its utilisation in the food industry. Heat-treated wheat flour may provide improved eating qualities in final wheat-based products since flour properties predominantly determine the texture and mouthfeel. Dry heat treatment of wheat kernels or milled wheat products involves heat transfer through means of air, a fluidising medium, or radiation—often resulting in moisture loss. Heat treatment leads to changes in the chemical, structural and functional properties of starch in wheat flour by inducing starch damage, altering its molecular order (which influences its crystallinity), pasting properties as well as its retrogradation and staling behaviour. Heat treatment also induces changes in gluten proteins, which may alter the rheological properties of wheat flour. Understanding the relationship between heat transfer, the thermal properties of wheat and the functionality of the resultant flour is of critical importance to obtain the desired extent of alteration of wheat starch properties and enhanced utilisation of the flour. This review paper introduces dry heat treatment methods followed by a critical review of the latest published research on heat-induced changes observed in wheat flour starch chemistry, structure and functionality.
Starch is an important polysaccharide that can be used as a gelling agent in confectionery products. SuChAQuality partner from South Africa has published a review paper about the chemistry of this gelling agent! Check the article for details!
Real-time benchtop NMR spectroscopy for the online monitoring of sucrose hydrolysis
Alper Soylera, Dylan Bouillaudb, Jonathan Farjonb, Patrick Giraudeaub, Mecit H. Oztop
The online monitoring of chemical reactions by using benchtop Nuclear Magnetic Resonance (NMR) spectroscopy has become increasingly attractive for the past few years. The use of quantitative online NMR spectroscopy is a promising alternative to traditional analytical methods with its rapid, quantitative and non-invasive nature that makes it applicable to complex and diverse biochemical mixtures like food systems. In this study, sucrose hydrolysis by invertase was chosen as a model reaction for online monitoring. Rather than conventional NMR spectroscopy experiments that rely on the use of deuterated water, the benchtop setting allows working in protonated solvents, and tailored water suppression techniques were used to make quantification more accurate. For the hydrolysis reaction, a 10% sucrose solution was hydrolyzed. The kinetic constants determined by the fractional conversion model were comparable to the results obtained in other studies. Quantitative online NMR spectroscopy can be considered as a promising tool for monitoring food processes in a continuous mode.
“ This study is not performed under SuChAQuality but contains information relevant to project”
The information contained in this document reflects only the view of the SuChAQuality project and in no way reflects the European Commission’s opinion for which cannot be held responsible for any use that may be made of the information it contains