Papers by Birthe Jespersen
Molecules, 2021
Cyclodextrins (CDs) are cyclic oligosaccharides that have found widespread application in numerou... more Cyclodextrins (CDs) are cyclic oligosaccharides that have found widespread application in numerous fields. CDs have revealed a number of various health benefits, making them potentially useful food supplements and nutraceuticals. In this study, the impact of α-, β-, and γ-CD at different concentrations (up to 8% of the flour weight) on the wheat dough and bread properties were investigated. The impact on dough properties was assessed by alveograph analysis, and it was found that especially β-CD affected the viscoelastic properties. This behavior correlates well with a direct interaction of the CDs with the proteins of the gluten network. The impact on bread volume and bread staling was also assessed. The bread volume was in general not significantly affected by the addition of up to 4% CD, except for 4% α-CD, which slightly increased the bread volume. Larger concentrations of CDs lead to decreasing bread volumes. Bread staling was investigated by texture analysis and low field nucle...
Journal of Agricultural and Food Chemistry, 2009
Equilibrium dialysis, molecular modeling, and multivariate data analysis were used to investigate... more Equilibrium dialysis, molecular modeling, and multivariate data analysis were used to investigate the nature of the molecular interactions between 21 vanillin-inspired phenolic derivatives, 4 bile salts, and 2 commercially available-glucan preparations, Glucagel and PromOat, from barley and oats. The two-glucan products showed very similar binding properties. It was demonstrated that the two-glucan products are able to absorb most phenolic derivatives at a level corresponding to the absorption of bile salts. Glucosides of the phenolic compounds showed poor or no absorption. The four phenolic derivatives that showed strongest retention in the dialysis assay shared the presence of a hydroxyl group in para-position to a CHO group. However, other compounds with the same structural feature but possessing a different set of additional functional groups showed less retention. Principal component analysis (PCA) and partial least-squares regression (PLS) calculations using a multitude of diverse descriptors related to electronic, geometrical, constitutional, hybrid, and topological features of the phenolic compounds showed a marked distinction between aglycon, glucosides, and bile salt retention. These analyses did not offer additional information with respect to the mode of interaction of the individual phenolics with the-glucans. When the barley-glucan was subjected to enzyme degradation, the ability to bind some but not all of the phenolic derivatives was lost. It is concluded that the binding must be dependent on multiple characteristics that are not captured by a single molecular descriptor.
Journal of Chemometrics, 2010
An extension of chemometric theory was experimentally explored to explain the physiochemical basi... more An extension of chemometric theory was experimentally explored to explain the physiochemical basis of the very high efficiency of soft modelling of data from nature. Soft modelling in self-organisation was interpreted by studying the unique chemical patterns of mutants in an isogenic barley model on endosperm development. Extremely reproducible, differential Near Infrared (NIR) spectral patterns specifically overviewed the effect on cell composition of each mutant cause. Extended Canonical Variates Analysis (ECVA) classified spectra in wild type, starch and protein mutants. The spectra were interpreted by chemometric data analysis and by pattern inspection to morphological, genetic, molecular and chemical information. Deterministic chemical reactions were defined in the glucan pathway. A drastic mutation in a gene controlling the starch/ß-glucan composition changed water activity that introduced a diffusive, stochastic effect on the catalysis of all active enzymes. 'Decision making' in self-organisation is autonomous and performed by the soft modelling of the chemical deterministic and stochastic reactions in the endosperm cell as a whole. Uncertainty in the analysis of endosperm emergence was experimentally delimited as the 'indeterminacy' in local molecular path modelling 'bottom up' and the 'irreducibility' of the phenomenological NIR spectra 'top down'. The experiment confirmed Ilya Prigogine's interpretation of self-organisation by his dynamic computer model programmed with a self-modeled non-local extension of quantum mechanics (QM). The significance of selforganisation explained by Prigogine here interpreted as physiochemical soft modelling introduces a paradigm shift in macroscopic science that forwards a major argument for soft mathematical modelling and chemometrics to obtain full scientific legitimacy.
Journal of Near Infrared Spectroscopy
Near Infrared hyperspectral imaging (HSI) offers a fast and non-destructive method for seed quali... more Near Infrared hyperspectral imaging (HSI) offers a fast and non-destructive method for seed quality assessment through combining spectroscopy and imaging. Recently, convolutional neural networks (CNN) have shown to be promising tools for red-green-blue (RGB) image or spectral cereal classification. This paper describes the design and implementation of deep CNN models capable of utilizing both the spatial and spectral dimension of HSI data simultaneously for analysis of bulk grain samples with densely packed kernels. Classification of eight grain samples, including six different wheat varieties, were used as a test case. The study shows that the CNN architecture ResNet, originally designed for RGB images, can be adapted to use the full spatio-spectral dimension of the HSI data through adding a linear down sample layer prior to the conventional ResNet architecture. Using traditional spectral pre-processing methods before passing the data to the CNN does not improve the classification ...
Food Research International, 2010
The rheology of crude and purified barley (BBG) and oat (OBG) β-glucan samples were characterized... more The rheology of crude and purified barley (BBG) and oat (OBG) β-glucan samples were characterized. Sample content and major impurities was characterized by Fourier-transform near infrared Raman and infrared (FT-IR) spectroscopy revealing substantial differences between the β-glucan samples. The purification procedure increased the β-glucan content from 66.7 to 82.4% and from 30.1 to 68.4% for BBG and OBG, respectively. Proton nuclear magnetic resonance (1 H NMR) analysis was applied to estimate the β-(1 → 3) to β-(1 → 4) linkage ratio of the β-glucans. The molar mass of BBG and OBG was determined by high performance size-exclusion chromatography (HPSEC) using β-glucan standards and was found to be 126 and 355 kDa, respectively. The viscosity of crude and purified β-glucans was studied at various concentrations (2.5, 5% w/v), temperatures (10-80°C) and shear rates (1-100 s − 1). BBG was characterized as a low-viscosity β-glucan with Newtonian flow behavior while OBG was characterized as a high-viscosity β-glucan with shear thinning flow behavior. At equivalent β-glucan concentration in solutions the viscosity for OBG was found to be~100 fold higher than for BBG. A direct viscosity dependence on exact β-glucan content regardless of amount and composition of αglucan impurities was found for both OBG and BBG. This study suggests that the structural characteristics of the β-glucan polymers such as molar mass are of greater functional importance than the presence of lager amounts of starch/α-dextrins as long as the β-glucan samples are compared at equivalent β-glucan doses.
QY Shu (ed.), Induced Plant Mutations in the Genomics Era. Food and Agriculture Organization of t... more QY Shu (ed.), Induced Plant Mutations in the Genomics Era. Food and Agriculture Organization of the United Nations, Rome, 2009, 182-186 Abstract This paper describes, with examples, how biochemical seed mutations can be used not only to improve quality in cereals, but also to ...
It is surprising that not even today do germination data seem fully integrated with malting data ... more It is surprising that not even today do germination data seem fully integrated with malting data in barley quality evaluation. In order to implement such an integration, pattern recognition multivariate data analysis (chemometrics) is essential. Inspired by the results from chemometric analyses of whole germination curves we tested a two-dimensional classification plot of barley samples based on separate estimates for "vigour" (g%1) germination energy (GE) as abscissa with limits at 70% and 30% and "viability" (g%3) as ordinate with limits at 98% and 92%. The seven barley classes obtained visualise the quality differences in a consistent and instructive way clearly differencing and ordering malting barleys with falling extract% and increasing wort β-glucan (mg/l) according to a subsequent validation analysis. "Vigour" g%1 could surprisingly be predicted by Partial Least Squares Regression (PLSR) correlation by Near Infrared Transmission (NIT) and by a separate set of ten physicalchemical analyses. Samples with "viability" g%3 lower than 92% were outliers. It was concluded that germination speed is connected with the structure of the seed, which regulates the availability of substrate for germ growth near connected to the speed of malt modification. It is suggested that a NIT PLSR prediction model for "vigour" can be used directly "on-line" for quality control in the grain industry and by plant breeders. A fast germinative classification plot can be established with NIT spectroscopy for "vigour" and the Tetrazolium germ-staining test for "viability" within two hours.
Journal of Agricultural and Food Chemistry, 2009
As documented by eight IAEA/FAO symposia (1968-82) on nutritionally improved seeds, a wide range ... more As documented by eight IAEA/FAO symposia (1968-82) on nutritionally improved seeds, a wide range of high lysine endosperm mutants were isolated in maize, sorghum and barley. These mutants observed by new spectroscopic screening methods can now be exploited to advance basic biological research and theory. Since 1982, effective methods to overview the physiochemical composition of seeds by Near Infrared Spectroscopy evaluated by chemometric data analysis have developed. Spectroscopic analyses by calibration have now substituted the wet analyses in the industry. In genetics there has traditionally been a differentiation between major genes for qualitative and minor ”polygenes” for quantitative traits. This view has been coupled with an incomplete understanding of pleiotropy. It is shown that seed spectra from isogenic barley endosperm mutants represent a coarse-grained physiochemical overview of the phenome that can be classified by chemometrics. Pleiotropy expressed by a gene is quant...
Metabolomics : Official journal of the Metabolomic Society, 2017
Mixed-linkage (1→3),(1→4)-β-d-glucans (BG) reduce cholesterol level and insulin response in human... more Mixed-linkage (1→3),(1→4)-β-d-glucans (BG) reduce cholesterol level and insulin response in humans. Despite this, their role in human metabolism and a mode of action remains largely unknown. To investigate the effects of three structurally different BG on human fecal metabolome in a full cross-over intervention using GC-MS metabolomics. Over three weeks of intervention, young healthy adults received food supplemented with BG from oat, two different BG from barley or a non-fiber control in a full cross-over design. Untargeted metabolomics and short chain fatty acid analysis was performed on day three fecal samples. ANOVA-simultaneous component analysis was applied to partition the data variation according to the study design, and PLS-DA was used to select most discriminative metabolite markers. Univariate and multivariate data analysis revealed a dominating effect of inter-individual variances followed by a gender effect. Weak effects of BG intake were identified including an increas...
Scientific reports, Jan 15, 2017
The development of crop varieties tolerant to growth temperature fluctuations and improved nutrit... more The development of crop varieties tolerant to growth temperature fluctuations and improved nutritional value is crucial due to climate change and global population growth. This study investigated the metabolite patterns of developing barley seed as a function of genotype and growth temperature for ideal vegetable protein production and for augmented β-glucan production. Seeds from three barley lines (Bomi, lys3.a and lys5.f) were sampled eight times during grain filling and analysed for metabolites using gas chromatography-mass spectrometry (GC-MS). The lys3.a mutation disrupts a regulator gene, causing an increase in proteins rich in the essential amino acid lysine, while lys5.f carries a mutation in an ADP-glucose transporter gene leading to a significant increase in production of mixed-linkage β-glucan at the expense of α-glucan. Unique metabolic patterns associated with the tricarboxylic acid cycle, shikimate-phenylpropanoid pathway, mevalonate, lipid and carbohydrate metabolism...
Journal of Cereal Science, 2017
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Applied spectroscopy, Jul 1, 2016
The supercontinuum laser is a new type of light source, which combines the collimation and intens... more The supercontinuum laser is a new type of light source, which combines the collimation and intensity of a laser with the broad spectral region of a lamp. Using such a source therefore makes it possible to focus the light onto small sample areas without losing intensity and thus facilitate either rapid or high-intensity measurements. Single seed transmission analysis in the long wavelength (LW) near-infrared (NIR) region is one area that might benefit from a brighter light source such as the supercontinuum laser. This study is aimed at building an experimental spectrometer consisting of a supercontinuum laser source and a dispersive monochromator in order to investigate its capability to measure the barley endosperm using transmission experiments in the LW NIR region. So far, barley and wheat seeds have only been studied using NIR transmission in the short wavelength region up to 1100 nm. However, the region in the range of 2260-2380 nm has previously shown to be particularly useful ...
The Faseb Journal, Apr 1, 2013
IOP Conference Series: Earth and Environmental Science, 2009
ABSTRACT This article was submitted without an abstract, please refer to the full-text PDF file.
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Papers by Birthe Jespersen