Classification and quantification of sucrose from sugar beet and sugarcane using optical spectroscopy and chemometrics.

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-Vis region. 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.

Molecular Dynamics of Jelly Candies by Means of Nuclear Magnetic Resonance Relaxometry.

1H spin-lattice Nuclear Magnetic Resonance relaxation studies have been performed for different kinds of Haribo jelly and Vidal jelly in a very broad frequency range from about 10 kHz to 10 MHz to obtain insight into the dynamic and structural properties of jelly candies on the molecular level. This extensive data set has been thoroughly analyzed revealing three dynamic processes, referred to as slow, intermediate and fast dynamics occurring on the timescale of 10-6 s, 10-7 s and 10-8 s, respectively. The parameters have been compared for different kinds of jelly for the purpose of revealing their characteristic dynamic and structural properties as well as to enquire into how increasing temperature affects these properties. It has been shown that dynamic processes in different kinds of Haribo jelly are similar (this can be treated as a sign of their quality and authenticity) and that the fraction of confined water molecules is reduced with increasing temperature. Two groups of Vidal jelly have been identified. For the first one, the parameters (dipolar relaxation constants and correlation times) match those for Haribo jelly. For the second group including cherry jelly, considerable differences in the parameters characterizing their dynamic properties have been revealed.

Water Dynamics in Starch Based Confectionery Products including Different Types of Sugar.

Starch-based confectionery products were prepared using different types of sugar. In addition to using different sugar, starch was replaced with soy protein isolate (SPI) in some of the products. 1H NMR spin-lattice relaxation experiments were performed for the collection of products in a broad frequency range from 4 KHz to 30 MHz to get insight into the influence of different sugar types and SPI on the dynamics of water in composite gel systems. The relaxation data have been decomposed into relaxation contributions associated with two different pools of water molecules characterized by different mobility. The translation dynamics of water molecules has been quantitatively described in terms of a dedicated relaxation model. The influence of the sample composition (the type of sugar and/or the presence of SPI) on the water mobility was thoroughly discussed. The results indicate that the addition of soy protein does not affect water dynamics for samples including sucrose. In addition, as the complementary measurements, physical properties of the products, such as the moisture content, water activity and texture, were investigated in terms of X-ray diffraction and thermogravimetric analysis.

Water dynamics in eggs by means of Nuclear Magnetic Resonance relaxometry.

1H Nuclear Magnetic Resonance relaxometry has been applied to reveal dynamical properties of water molecules embedded into egg yolk and white of three species: turkey, chicken and quail. Two fractions of water molecules, referred to as confined-water and free-water fractions, have been revealed. It has been demonstrated that translation diffusion of the confined-water fraction is three-dimensional. The dynamics of the confined-water has been quantitatively described in terms of diffusion coefficients and rotational correlation times. The parameters have been compared for egg yolk and white for all the species. In addition to these quantities, the number of the confined-water molecules per unit volume has been provided for all cases. The obtained parameters provide insight into the dynamics of water in eggs of different origin and allow to identify similarities and differences between them in connection to the structure of the network formed by the macromolecular fraction of egg yolk and white.

Role of 'D-allulose' in a starch based composite gel matrix.

Type of sugar and gelling agents used in confectionery formulations have vital importance since they directly influence physicochemical properties during storage. In this study, the effect of a non-caloric rare sugar, D-allulose (formerly called D-psicose) on the starch based confectionery gels were investigated in the presence and absence of soy protein isolate (SPI) using different experimental techniques for 28 days. For characterization of the formulized gel systems, common techniques were used (SEM, DSC, XRD, moisture content, water activity, hardness and color). Time Domain Nuclear Magnetic Resonance (TD-NMR) technique was also employed to explain dynamics in the systems. Sugar type was found to be a very significant factor affecting gel characteristics and retrogradation. Results showed that D-allulose containing formulations were less prone to retrogradation and showed smaller changes upon storage by supporting presence of better gel network. According to X-ray results, sucrose containing formulations were more susceptible to crystallization. T2 relaxation spectra obtained from NMR experiments showed that number of distinct peaks reduced with the addition of SPI while relaxation times of peaks changed when different type of sugar.

Characterization of Emulsion Stabilization Properties of Gum Tragacanth, Xanthan Gum and Sucrose Monopalmitate: A Comparative Study.

Emulsification effect of gum tragacanth (GT) obtained from Astragalus species is gaining particular interest in recent years. In this study, stabilization effect of GT, xanthan gum (XG), and sucrose monopalmitate (SMP) was investigated by keeping their concentration constant (0.5% w/v) for the oil-in-water emulsions containing 20% (v/v) sun flower oil and 2% (w/v) whey protein isolate. Emulsification was achieved by using high shear homogenization. Particle size and T2 (spin-spin relaxation time) measurements were performed for the characterization and repeated over the course of 28 days. Emulsion stability index (ESI [%]) was measured and rheological characterization was also performed. The lowest particle size was found for the XG emulsions and this was attributed to the pseudoplastic behavior of xanthan compared to GT (nXanthan = 0.188 ≪ nGT = 0.721). Xanthan emulsions thinned out dramatically when sheared during homogenization, and consequently, floccules formed could have been disrupted more resulting in smaller particle size. Result of rheological experiments showed that SMP emulsions were fit to Newtonian model, while XG and GT showed shear thinning behavior and fit to a power law model. Apparent viscosity of XG emulsions was found significantly higher than the GT ones. The most stable emulsions were the ones prepared by XG and they remained stable during 28 days. Although GT emulsions could not protect their stability during 28 days, ESI (%) results were found similar with XG indicating promising emulsification effect of GT. PRACTICAL APPLICATION: Gum tragacanth, xanthan gum, and sucrose monopalmitate have been used to formulate oil-in-water emulsions. The final formulated products can be used in emulsion-based food products to increase their stability and shelf life.

Effect of d-psicose substitution on gelatin based soft candies: A TD-NMR study.

Confectionary gels are considered as composite gel systems composed of high amount of sugar and gelling agent such as gelatin or starch. d-Psicose is classified as a type of rare sugar, which is a C-3 epimer of fructose and has 70% of the sweetness of sucrose with a caloric value of 0.39 kcal/g. Utilization of d-psicose in food products is gaining particular interest due to its low caloric value. In this study, gelatin-based soft candies were formulated, and the effect of d-psicose substitution was explored on the quality of the products. For characterization of the soft candies, moisture content, water activity, color, hardness, and glass transition temperature of samples were investigated. X-ray diffraction analysis was also performed to explain the crystallization tendency of jelly candies. Results showed that, the softest sample with the highest moisture content and the smallest crystallization tendency was the sample that included the highest amount of d-psicose. Time domain (TD) NMR relaxometry experiments were also conducted on gel samples, and three distinct proton populations were observed in the relaxation spectrum for all formulations. Spin-lattice relaxation times obtained through monoexponential fitting (T1 ) were also obtained to explain some quality parameters.