Evaluation of the use of attenuated total reflectance mid infrared spectroscopy to determine fatty acids in intact seeds of barley (Hordeum vulgare)

Attenuated total reflectance (ATR) mid-infrared (MIR) spectroscopy was evaluated to measure fatty acids (FA) and total lipids in intact seed barley (Hordeum vulgare) samples. Results from this study demonstrated the capability of ATR-MIR spectroscopy coupled with partial least squares (PLS) regression to measure FA non-destructively in intact barley seeds. The coefficients of determination in cross validation (R²) and the standard error of cross validation (SECV) were 0.76 and 0.004 g 100 g⁻¹ for stearic, 0.75 and 0.037 g 100 g⁻¹ for oleic, 0.45 and 0.02 g 100 g⁻¹ for palmitic acids, and 0.89 and 0.13 g 100 g⁻¹ for total lipids, respectively. The practical implications of this study showed that ATR-MIR spectroscopy confer valuable benefits for the grain industry and in particular in breeding programs as a non-destructive high throughput method.     

Antioxidant activities of malt extract from barley (Hordeum vulgare L.) toward various oxidative stress in vitro and in vivo

The antioxidant activities of malt extract from barley were evaluated by various methods in vitro and in vivo. Scavenging effects on the hydroxyl and superoxide radicals, and protection against reactive oxygen species induced lipid, protein and DNA damage were evaluated. The d-galactose induced mouse aging model was used to evaluate ability of malt extract to behave as an antioxidant in vivo. The extract exhibited high antioxidant activities both in vitro and in vivo, evidenced by its ability to scavenge hydroxyl- and superoxide-radicals, high reducing power, and protection against biological macromolecular oxidative damage. Furthermore, malt extract prevented the decrease of antioxidant enzyme activities, decreased liver and brain malondialodehyde levels and carbonyl content, and improved total antioxidant capability in d-galactose-treated mice. In conclusion, these results demonstrate potential antioxidant activities and antiaging effect of malt, providing scientific support for the empirical use of malt as an antioxidant for diseases caused by reactive oxygen species.     

Characterisation of grain quality in diverse sorghum germplasm using a Rapid Visco-Analyzer and near infrared reflectance spectroscopy

BACKGROUND: Twenty‐two diverse sorghum landraces, classified as normal and opaque types obtained from Ethiopia, were characterised for grain quality parameters using near infra‐red spectroscopy (NIRS), chemical and Rapid Visco‐Analyzer (RVA) characteristics. RESULTS: Protein content ranged from 77 to 182 g kg^?1, and starch content from 514 to 745 g kg^?1. The NIRS analysis indicated the pig faecal digestible energy range from 14.6 to 15.7 MJ kg^?1 as fed, and the ileal digestible energy range from 11.3 to 13.9 MJ kg^?1 as fed. The normal sorghums had higher digestible energy than the opaque sorghums, which exhibited lower RVA viscosities, and higher pasting temperatures and setback ratios. The RVA parameters were positively correlated with the starch content and negatively correlated with the protein content. The normal and opaque types formed two distinct groups based on principal component and cluster analyses. CONCLUSION: The landraces were different for the various grain quality parameters with some landraces displaying unique RVA and NIRS profiles. This study will guide utilisation of the sorghum landraces in plant improvement programs, and provides a basis for further studies into how starch and other constituents behave in and affect the properties of these landraces. Copyright © 2011 Society of Chemical Industry     

Malting revisited: Germination of barley (Hordeum vulgare L.) is inhibited by both oxygen deficiency and high carbon dioxide concentrations

During malting, barley (Hordeum vulgare L.) seeds are germinated to promote the mobilisation of storage compounds. Germination is strongly influenced by O₂ and CO₂; however, any distinction between the particular effects is missing. Since, in this study, the ambient O₂ concentration was maintained when high CO₂ concentrations were applied, for the first time the impacts of CO₂ and of O₂ deficiency could be distinguished unambiguously.Germination was inhibited by both O₂ deficiency and high CO₂ (80%) concentrations, documented by the lack of any growth of coleoptiles and any increase of α-amylase and β-glucanase activity. In contrast, the related impacts of O₂ starvation and high CO₂ on fermentation differ strongly, demonstrated by quite different patterns of ethanol emission. Additionally, the stress metabolism - monitored by the means of GABA accumulation - was also differently impacted. The elucidation of the underlying, so far unknown, mechanisms will provide novel opportunities to improve malting.     

Free and bound total phenolic concentrations,antioxidant capacities,and profiles of proanthocyanidins and anthocyanins in whole grain rice (Oryza sativa L.) of different bran colours

To study the polyphenols in whole grain rice varying in bran colour, the total phenolics, flavonoids and antioxidant capacities of the solvent-extractable (Free) and cell-wall bound (Bound) fractions and the profiles of proanthocyanidins and anthocyanins were determined. Red and purple bran rices had significantly higher total (sum of Free- and Bound-) phenolic (PC) and flavonoid (FC) concentrations and antioxidant capacities than light-coloured bran rice or other cereals (P < 0.05), due to their higher concentrations of proanthocyanidins and anthocyanins, respectively. The concentrations of the Bound-PC and FC accounted for approximately half of the total PC and FC in the light-coloured bran rice, but were lower than those in purple and red bran rice (P < 0.05). High correlations were found between the concentrations of total phenolics and the three antioxidant capacity assays except for those in the bound fraction when related to iron chelating capacity. The concentrations of proanthocyanidins in red bran rice was 1.27 mg/g and its composition was 6.5%, 33.5%, 30.6% and 29.4% of 1–3, 4–6, 7–10 mers, and polymer (>10 mers), respectively. Cyanidin-3-glucoside was the predominant anthocyanin and peonidin-3-glucoside was the second highest; the profiles varied between purple bran cultivars. Whole grain rice differing in bran colour contained unique polyphenol subgroups, which have been proposed to positively impact human health.     

Quantification of total polysaccharides and triterpenoids in Ganoderma lucidum and Ganoderma atrum by near infrared spectroscopy and chemometrics

Two chemometrics, the partial least-squares (PLS) and radial basis function (RBF) network were performed to develop a quantification method for total polysaccharides and triterpenoids in Ganoderma lucidum and Ganoderma atrum from different origins based on near infrared reflectance spectroscopy (NIR). The influences of spectral window and spectral pre-treatments were initially studied in the construction of PLS model. The best result was obtained when the standard normal transformation (SNV) +1st derivative spectrum over 4100–7750 cm⁻¹ was used for the modelling. Then based on each principle, both of the two models were optimised respectively. The final results with high determination coefficient (R²) (higher than 0.973, 0.989 for PLS and RBF, respectively) and low root mean square errors of prediction (RMSEP) (low to 0.1109 and 0.01298 for polysaccharides and triterpenoids, respectively) confirm the good predictability of the two models. The overall results show that NIR spectroscopy combined with chemometrics can be efficiently utilised for accurate analysis of routine chemical compositions in G. lucidum and G. atrum.     

Electrophoretic and HPLC methods for comparative study of the protein fractions of malts,worts and beers produced from Scarlett and Prestige barley (Hordeum vulgare L.) varieties

Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and reversed-phase high performance liquid chromatography (RP-HPLC) methods were used for studying the protein fractions (hordeins; albumins and other soluble proteins) of Scarlett and Prestige barley malts and to follow changes of the protein profile of worts and beers from these two malt varieties. Similar industrial brewing conditions were applied for both varieties.     

Rapid measurement of total acid content (TAC) in vinegar using near infrared spectroscopy based on efficient variables selection algorithm and nonlinear regression tools

Total acid content (TAC) is an important index in assessing vinegar quality. This work attempted to determine TAC in vinegar using near infrared spectroscopy. We systematically studied variable selection and nonlinear regression in calibrating regression models. First, the efficient spectra intervals were selected by synergy interval PLS (Si-PLS); then, two nonlinear regression tools, which were extreme learning machine (ELM) and back propagation artificial neural network (BP-ANN), were attempted. Experiments showed that the model based on ELM and Si-PLS (Si-ELM) was superior to others, and the optimum results were achieved as follows: the root mean square error of prediction (RMSEP) was 0.2486 g/100mL, and the correlation coefficient (R(p)) was 0.9712 in the prediction set. This work demonstrated that the TAC in vinegar could be rapidly measured by NIR spectroscopy and Si-ELM algorithm showed its superiority in model calibration.     

Simultaneous analysis of main catechins contents in green tea (Camellia sinensis (L.)) by Fourier transform near infrared reflectance (FT-NIR) spectroscopy

This paper reported the results of simultaneous analysis of main catechins (i.e., EGC, EC, EGCG and ECG) contents in green tea by the Fourier transform near infrared reflectance (FT-NIR) spectroscopy and the multivariate calibration. Partial least squares (PLS) algorithm was conducted on the calibration of regression model. The number of PLS factors and the spectral preprocessing methods were optimised simultaneously by cross-validation in the model calibration. The performance of the final model was evaluated according to root mean square error of cross-validation (RMSECV), root mean square error of prediction (RMSEP) and correlation coefficient (R). The correlations coefficients (R) in the prediction set were achieved as follows: R = 0.9852 for EGC model, R = 0.9596 for EC model, R = 0.9760 for EGCG model and R = 0.9763 for ECG model. This work demonstrated that NIR spectroscopy with PLS algorithm could be used to analyse main catechins contents in green tea.     

The application of near infrared spectroscopy technology and a remote reflectance fibre-optic probe for the determination of peptides in cheeses (cow’s,ewe’s and goat’s) with different ripening times

The use of near infrared spectroscopy (NIRS) technology employing a remote reflectance fibre-optic probe (with a 5 cm × 5 cm quartz window) for the analysis of the hydrophilic (HI) and hydrophobic (HO) peptides and the ratio HO/HI was assayed. To do so, cheeses with known and varying percentages of cow’s, ewe’s and goat’s milk were elaborated (112 samples). Ripening controls were performed over 6 months, and the chemical data obtained by reversed-phase high performance liquid chromatography used as reference. The regression method employed was modified partial least squares (MPLS). The multiple correlation coefficients (RSQ) and prediction corrected standard errors (SEP (C)) obtained 0.879 and 1.83% for hydrophilic (HI) and 0.879 and 1.83% for hydrophobic (HO) peptides, respectively, and 0.890 and 0.03% for the ratio HO/HI. The method allows immediate control by direct application of the fibre-optic probe to the cheese without prior sample treatment or destruction.     

The mineral composition (Ca,P, Mg,K, Na) in cheeses (cow’s,ewe’s and goat’s) with different ripening times using near infrared spectroscopy with a fibre-optic probe

The results of this work show that it is possible to rapidly quantify calcium, phosphorus, magnesium, potassium and sodium in unknown cheeses elaborated with percentages (0–100%) of milk from different species (cow, ewe, goat) by direct application of the fibre-optic probe on the sample without previous destruction or treatment of the sample. Of the total number of samples, 170 were used to develop the calibration models using the Modified Partial Least Squares (MPLS) regression method and 57 samples were used for external validation. The multiple correlation coefficients (RSQ) and prediction corrected standard errors (SEP (C)) obtained for calcium (0.74, 0.64), phosphorus (0.69, 0.29), potassium (0.86, 0.13), and sodium (0.92, 0.71) in g/kg respectively and magnesium (0.72, 30.9) in ppm, indicated that the models developed allow the determination of Ca, P, K, Na and Mg in unknown samples of cheeses of varying compositions up to 6 months of ripening.     

Saffron (Crocus sativus L.) increases glucose uptake and insulin sensitivity in muscle cells via multipathway mechanisms

Saffron (Crocus sativus Linn.) has been an important subject of research in the past two decades because of its various biological properties, including anti-cancer, anti-inflammatory, and anti-atherosclerotic activities. On the other hand, the molecular bases of its actions have been scarcely understood. Here, we elucidated the mechanism of the hypoglycemic actions of saffron through investigating its signaling pathways associated with glucose metabolism in C₂C₁₂ skeletal muscle cells. Saffron strongly enhanced glucose uptake and the phosphorylation of AMPK (AMP-activated protein kinase)/ACC (acetyl-CoA carboxylase) and MAPKs (mitogen-activated protein kinases), but not PI 3-kinase (Phosphatidylinositol 3-kinase)/Akt. Interestingly, the co-treatment of saffron and insulin further improved the insulin sensitivity via both insulin-independent (AMPK/ACC and MAPKs) and insulin-dependent (PI 3-kinase/Akt and mTOR) pathways. It also suggested that there is a crosstalk between the two signaling pathways of glucose metabolism in skeletal muscle cells. These results could be confirmed from the findings of GLUT4 translocation. Taken together, AMPK plays a major role in the effects of saffron on glucose uptake and insulin sensitivity in skeletal muscle cells. Our study provides important insights for the possible mechanism of action of saffron and its potential as a therapeutic agent in diabetic patients.     

A novel approach to authenticity control of whole grain durum wheat (Triticum durum Desf.) flour and pasta,based on analysis of alkylresorcinol composition

Since durum wheat is ∼20% more expensive than common wheat and considered of superior quality for the manufacture of pasta products, efficient methods for the detection of accidental or intentional admixtures of common wheat to durum wheat products are required. This paper describes a novel approach for the detection and quantification of whole grain common wheat adulteration in whole grain durum flour and dried pasta. We found that differences in the C17:0 to C21:0 alkylresorcinol homologue ratios between the two cereal species may serve as a suitable tool for whole grain durum product authentification. To detect and estimate adulteration, the C17:0/C21:0 ratios of flour and pasta admixtures with added whole grain flour of common wheat were analysed. A linear relationship between C17:0/C21:0 ratios and level of admixture in pasta samples showed that adulteration can be estimated within the range of 5–100% of admixture. Furthermore, di- and triunsaturated as well as oxygenated alk(en)ylresorcinols are reported to occur in Triticum durum Desf. for the first time.     

Detection of granary weevil Sitophilus granarius (L.) eggs and internal stages in wheat grain using soft X-ray and image analysis

In order to prevent grain mass and quality losses, rapid methods for early detection of insect infestation of cereal grain during trade and storage are urgently needed. Amongst many options, the soft X-ray method using roentgenograms is one of the most frequently applied. It has been shown that when some corrections for working parameters of the equipment used are made and some modification of the digital image analysis introduced, the soft X-ray method is suitable for accurate detection of granary weevil eggs laid in wheat kernels if at least 5 days after oviposition have elapsed.     

Changes in functional characteristics of starch during water caltrop (Trapa Quadrispinosa Roxb.) growth

This study was carried out to establish the changes of physicochemical properties of Taiwan’s water caltrop (Trapa Quadrispinosa Roxb.) starch at various stages of maturity during growth. Investigations showed that the dry matter and starch contents of water caltrop increased from 9.7% to 25.61% and from 49.4% to 79.4% (d.b.), respectively, as growth progressed (from 14th to 42nd day after fruit development). The shape of the starch granules was smooth, oval and poly-angular during the growth period. The granule size of starch increased with increase of physiological age, ranging from 19.4 μm to 32.2 μm. The X-ray diffraction patterns could be classified as a typical A-type crystalline structure. Swelling power and solubility of water caltrop starch increased with increases of growth time. Starches obtained from water caltrop at the early stage exhibited a lower gelatinization temperature (T_o, T_p, T_c) and gelatinization enthalpy (ΔH) than did the late stage of maturity. The rapid viscosity analyzer (RVA) parameters suggested that water caltrop starch paste had a low breakdown, and appeared to be thermo-stable, at the early harvest time. The pasting temperature, peak viscosity, final viscosity and setback value of water caltrop starch increased as growth progressed. Different starch granular size and amylose content could be the major factors influencing starch physicochemical properties during maturity.     

Application of linear/non-linear classification algorithms in discrimination of pork storage time using Fourier transform near infrared (FT-NIR) spectroscopy

To address the rapid and nondestructive determination of pork storage time associated with its freshness, Fourier transform near infrared (FT-NIR) spectroscopy technique, with the help of classification algorithm, was attempted in this work. To investigate the effects of different linear and non-linear classification algorithms on the discrimination results, linear discriminant analysis (LDA), K-nearest neighbors (KNN), and back propagation artificial neural network (BP-ANN) were used to develop the discrimination models, respectively. The number of principal components (PCs) and other parameters were optimized by cross-validation in developing discrimination models. Experimental results showed that the performance of BP-ANN model was superior to others, and the optimal BP-ANN model was achieved when 5 PCs were included. The discrimination rates of the BP-ANN model were 99.26% and 96.21% in the training and prediction sets, respectively. The overall results sufficiently demonstrate that the FT-NIR spectroscopy technique combined with BP-ANN classification algorithm has the potential to determine pork storage time associated with its freshness.     

Lipid components and water soluble metabolites in salted and dried tuna (Thunnus thynnus L.) roes

The salted and dried product of tuna roe (bottarga) is a seafood characteristic of the Mediterranean area and exported all over the world. Samples of bottarga from bluefin tunas (Thunnus thynnus, L.) caught in the southwest Mediterranean sea were analysed. The samples were characterised by high content of marine wax esters (55–67 mol% of lipid classes), of docosahexaenoic (22:6 n-3, 25 w%) and oleic (18:1 n-9, 19 w%) fatty acids. Cholesterol was detected as 7–9 w% of lipids. Free fatty acids, index of lipid hydrolysis, represented 32–39 mol% over total fatty acids. Among metabolites, nutrients as taurine, nicotinamide and β-alanine, were found. The microflora comprised staphylococci, enterococci (2.2 log₁₀ CFU/g) and lactic acid bacteria (3 log₁₀ CFU/g). The food-borne pathogens Staphylococcus aureus, Listeria monocytogenes and Salmonella spp. were not detected. These findings indicate tuna bottarga as valuable source of nutrients.