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In this study, acetic acid (AA-2% w/v), a combination of acetic acid and citric acid (AA-1% w/v + CA-1% w/w), and three different concentrations of citric acid (CA-2, 4 and 6% w/w) were used to create chitosan solution. The FTIR analysis showed the presence of residual CA in all the CA-containing samples where no trace of AA was observed. The tensile strengths of the CA-containing samples were lower than the AA samples. Whereas the values for the elongation at break of the CA samples were higher than the AA samples, which kept increasing with an increasing CA content due to the plasticizing effect from residual citric acid. The elongation at break values for 4 and 6% CA-containing samples were 98% higher than the AA samples. The samples prepared with CA showed shorter LVE regions that reduced with an increasing CA concentration compared to the AA samples. Different acid concentrations did not have a large effect on the gelation time. However, CA-containing samples showed higher viscosities as compared to the AA-containing solution, which increased with an increasing CA content. The water vapour transmission rates of the CA-containing samples were lower than the others. All the chitosan solutions suppressed the growth of the two test strains, and none of the variants reached an abs 600 nm at 0.2. [ABSTRACT FROM AUTHOR]

In this work, a new magnetic ligand fishing probe for discovery of DPP-IV inhibitory ligands was developed and it was tested as a proof of concept on the fruit extract of Vaccinium vitis-idaea (lingonberry). The ligands were shown to have appreciable dipeptidyl peptidase IV (DPP-IV) inhibitory activity (IC50: 31.8 μg mL-1).) Inhibition of DPP-IV is a well-known therapeutic approach for management of type 2 diabetes (T2D). DPP-IV was successfully immobilized onto magnetic beads and was shown to retain its catalytic activity and selectivity over a model mixture. A total of four ligands were successfully fished out and identified as cyanidin-3-galactoside (2), cyanidin-3-arabinoside (3), proanthocynidin A (4), and 10-carboxyl-pyranopeonidin 3-O-(6″-O-p-coumaroyl)-glucoside (5) using HPLC/HRMS. [ABSTRACT FROM AUTHOR]

The potential of dry-film Fourier-transform infrared (FTIR) measurements as a monitoring tool for enzymatic hydrolysis of protein-based substrates is explored in this study. As a proof-of-concept, the enzymatic digestion of bovine serum albumin using Alcalase was monitored. To evaluate the analytical approach on complex substrates with industrial relevance, salmon- and chicken-based substrates were digested for 80 minutes using Alcalase and a total of 12 FTIR spectra were acquired during the course of the hydrolysis. The observed changes in the IR spectral features as a function of hydrolysis time were found to be in agreement with the breakdown of the amide backbone and formation of amino and carboxylate terminals. Some of the most consistent markers for hydrolysis time were the bands at 1516 cm−1 (–NH3+) and ∼1400 cm−1 (–COO−). Moreover, principal component analysis (PCA) of the FTIR spectra was used to demonstrate the systematic relationship of the hydrolysis time with key variables (wavelengths) in the protein backbone region (800–1800 cm−1). Scores in the first principal component versus the hydrolysis time have been shown to provide an overview of the process dynamics related to protein structural changes. The herein presented results suggest that dry-film FTIR measurements have potential as a rapid tool for monitoring industrial protein hydrolysis processes. [ABSTRACT FROM AUTHOR]

Unstable breadmaking quality of wheat due to environmental influence has been a problem for Norwegian milling industries. Large variation in gluten quality was observed from field trials with Norwegian winter wheat conducted in several locations between 2005 and 2013. Moreover, extremely poor gluten quality was observed in several locations in the 2007 and 2011 season, and indicated almost complete loss of breadmaking quality. To investigate the environmental factors which cause extremely weak gluten, gluten proteins were characterized in samples selected within the 2011 season. The results revealed that the proportion of large glutenin polymers decreased in wheat samples with extremely weak gluten. Moreover, re-polymerization of large glutenin polymers, which normally occur during the resting period of a dough, did not take place in gluten prepared from these samples. Incubation of total proteins extracted from these samples in anin vitrosystem showed a drastic degradation of gluten proteins indicating protease activities. The origin of the proteases remains unclear; however, exogenous proteases derived fromFusariumspp. seem to play a key role for protein degradation, and thus causing severe quality deficiency. A genotypic difference was found between the two cultivars and one of them had higher resistance against the factors influencing gluten quality in negative way. [ABSTRACT FROM AUTHOR]

BACKGROUND Negative health effects associated with excessive sodium (Na) intake have increased the demand for tasty low-Na products (<2% NaCl) rather than traditional heavily salted fish products (∼20% NaCl). This study investigates the causes of improved yield and liquid retention of fish muscle brined with a combination of salt ( NaCl) and sodium bicarbonate ( NaHCO3). RESULTS Water characteristics and microstructure of saithe ( Pollachius virens L.) muscle brined in solutions of NaCl and NaHCO3 or NaCl alone were compared using low-field nuclear magnetic resonance ( LF-NMR) T2 relaxometry, microscopy, salt content, liquid retention and colorimetric measurements. Saithe muscle was brined for 92 h in 0, 30, 60, 120 or 240 g kg−1 NaCl or the respective solutions with added 7.5 g kg−1 NaHCO3. NaHCO3 inclusion improved the yield in solutions ranging from 0 to 120 g kg−1 NaCl, with the most pronounced effect being observed at 30 g kg−1 NaCl. The changes in yield were reflected in water mobility, with significantly shorter T2 relaxation times in all corresponding brine concentrations. Salt-dependent microstructural changes were revealed by light microscopy, where NaHCO3 supplementation resulted in greater intracellular space at 30 and 60 g kg−1 NaCl. CONCLUSION Sodium bicarbonate addition to low-salt solutions can improve yield and flesh quality of fish muscle owing to altered water mobility and wider space between the muscle cells. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: The aim of this study was to investigate the effects of low to moderate temperatures on gluten functionality and gluten protein composition. Four spring wheat cultivars were grown in climate chambers with three temperature regimes (day/night temperatures of 13/10, 18/15 and 23/20 °C) during grain filling. RESULTS: The temperature strongly influenced grain weight and protein content. Gluten quality measured by maximum resistance to extension (Rmax) was highest in three cultivars grown at 13 °C. Rmax was positively correlated with the proportion of sodium dodecyl sulfate-unextractable polymeric proteins (%UPP). The proportions of ω-gliadins and D-type low-molecular-weight glutenin subunits (LMW-GS) increased and the proportions of α- and γ-gliadins and B-type LMW-GS decreased with higher temperature, while the proportion of high-molecular-weight glutenin subunits (HMW-GS) was constant between temperatures. The cultivar Berserk had strong and constant Rmax between the different temperatures. CONCLUSION: Constant lowtemperature, even as lowas 13 °C, had no negative effects on gluten quality. The observed variation in Rmax related to temperature could be explained more by%UPPthan by changes in the proportions of HMW-GS or other gluten proteins. The four cultivars responded differently to temperature, as gluten from Berserk was stronger and more stable over a wide range of temperatures. [ABSTRACT FROM AUTHOR]

One Norwegian and one UK spring wheat cultivar, Bjarne and Cadenza, respectively, were grown in climate chambers to investigate the effects of lower to moderate temperatures during grain filling on the gluten quality. Two experiments were carried out with weekly fertilization until anthesis, while post-anthesis fertilization was applied in a third experiment. The proportions of different gluten proteins were affected by temperature in a similar manner for both cultivars when grown without post-anthesis fertilization. However, whereas low temperature strongly decreased %UPP for Cadenza, Bjarne had high %UPP at all temperature regimes. The results indicated that the assembly of glutenin polymers in Bjarne was less sensitive to variation in temperature than in Cadenza. Thus, our results suggested that the temperature influenced the proportion of different gluten proteins in both cultivars, while its effects on the assembly of the glutenin polymers were cultivar dependent. The duration of grain filling was longer at the lower temperatures, and this was associated with increased grain weight. Temperature had little effect on the amount of protein accumulated per grain, thus the proportion of proteins was strongly decreased at lower temperatures. This was to some extent, but not fully counteracted by post-anthesis fertilization. [ABSTRACT FROM AUTHOR]

Single-channel optical density measurements of population growth are the dominant large scale phenotyping methodology for bridging the gene-function gap in yeast. However, a substantial amount of the genetic variation induced by single allele, single gene or double gene knock-out technologies fail to manifest in detectable growth phenotypes under conditions readily testable in the laboratory. Thus, new high-throughput phenotyping technologies capable of providing information about molecular level consequences of genetic variation are sorely needed. Here we report a protocol for high-throughput Fourier transform infrared spectroscopy (FTIR) measuring biochemical fingerprints of yeast strains. It includes high-throughput cultivation for FTIR spectroscopy, FTIR measurements and spectral pre-treatment to increase measurement accuracy. We demonstrate its capacity to distinguish not only yeast genera, species and populations, but also strains that differ only by a single gene, its excellent signal-to-noise ratio and its relative robustness to measurement bias. Finally, we illustrated its applicability by determining the FTIR signatures of all viable Saccharomyces cerevisiae single gene knock-outs corresponding to lipid biosynthesis genes. Many of the examined knock-out strains showed distinct, highly reproducible FTIR phenotypes despite having no detectable growth phenotype. These phenotypes were confirmed by conventional lipid analysis and could be linked to specific changes in lipid composition. We conclude that the introduced protocol is robust to noise and bias, possible to apply on a very large scale, and capable of generating biologically meaningful biochemical fingerprints that are strain specific, even when strains lack detectable growth phenotypes. Thus, it has a substantial potential for application in the molecular functionalization of the yeast genome. [ABSTRACT FROM AUTHOR]

Characterization and identification of fungi in food industry is an important issue both for routine analysis and trouble-shooting incidences. Present microbial techniques for fungal characterization suffer from a low throughput and are time consuming. In this study we present a protocol for high-throughput microcultivation and spectral characterization of fungi by Fourier transform infrared spectroscopy. For the study 11 species of in total five different fungal genera ( Alternaria, Aspergillus, Mucor, Paecilomyces, and Phoma) were analyzed by FTIR spectroscopy. All the strains were isolated from trouble-shooting incidents in the production of low and high acid beverages. The cultivation was performed in malt extract broth (liquid medium) in a Bioscreen C system, allowing high-throughput cultivation of 200 samples at the same time. Mycelium was subsequently investigated by high-throughput Fourier transform infrared spectroscopy. Four spectral regions, fatty acids + lipid (3200-2800 cm-1, 1300-1000 cm-1), protein-lipid (1800-1200 cm-1), carbohydrates (1200-700 cm-1) and 'finger print' (900-700 cm-1) were evaluated for reproducibility and discrimination ability. The results show that all spectral regions evaluated can be used as spectroscopic biomarkers for differentiation of fungi by FTIR. The influence of different growth times on the ability of species discrimination by FTIR spectroscopy was investigated, and an optimal separation of all five genera was observed after five days of growth. This work presents a novel concept for high-throughput cultivation of fungi for FTIR spectroscopy that enables characterization or identification of hundreds of strains per day. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Presents a list of articles published on various journals related to U.S. history. "The Economic Returns of Agricultural Education," by Harold F. Breimyer; "Black Legislators of Reconstruction Texas," by Alwyn Barr; "The Evolution of Modern Architecture in Long Beach," by Louise H. Ivers.

Recently, two chicken breast fillet abnormalities, termed Wooden Breast (WB) and Spaghetti Meat (SM), have become a challenge for the chicken meat industry. The two abnormalities share some overlapping morphological features, including myofiber necrosis, intramuscular fat deposition, and collagen fibrosis, but display very different textural properties. WB has a hard, rigid surface, while the SM has a soft and stringy surface. Connective tissue is affected in both WB and SM, and accordingly, this study's objective was to investigate the major component of connective tissue, collagen. The collagen structure was compared with normal (NO) fillets using histological methods and Fourier transform infrared (FTIR) microspectroscopy and imaging. The histology analysis demonstrated an increase in the amount of connective tissue in the chicken abnormalities, particularly in the perimysium. The WB displayed a mixture of thin and thick collagen fibers, whereas the collagen fibers in SM were thinner, fewer, and shorter. For both, the collagen fibers were oriented in multiple directions. The FTIR data showed that WB contained more β-sheets than the NO and the SM fillets, whereas SM fillets expressed the lowest mature collagen fibers. This insight into the molecular changes can help to explain the underlying causes of the abnormalities. [ABSTRACT FROM AUTHOR]

In the present study, Fourier‐transform infrared spectroscopy (FTIR) is investigated as a method to measure connective tissue components that are important for the quality of Atlantic cod filets (Gadus morhua L.). The Atlantic cod used in this study originated from a feeding trial, which found that fish fed a high starch diet contained relative more collagen type I, while fish fed a low starch (LS) diet contained relative more glycosaminoglycans (GAGs) in the connective tissue. FTIR spectra of pure commercial collagen type I and GAGs were acquired to identify spectral markers and compare them with FTIR spectra and images from connective tissue. Using principal component analysis, high and LS diets were separated due to collagen type I in the spectral region 1800 to 800 cm−1. The spatial distribution of collagen type I and GAGs were further investigated by FTIR imaging in combination with immunohistochemistry. Pixel‐wise correlation images were calculated between preprocessed connective tissue images and preprocessed pure components spectra of collagen type I and GAGs, respectively. For collagen, the FTIR images reveal a collagen distribution that closely resembles the collagen distribution as imaged by immunohistochemistry. For GAGs, the concentration is very low. Still, the FTIR images detect the most GAGs rich regions. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate effects of temperature during grain filling on gluten quality characteristics at a lower to moderate temperature range. Experiments with two wheat varieties grown in field covered by polypropylene tunnels during grain filling were performed in two seasons. Mean day temperature differences achieved within the tunnel were approximately 2-2.5 °C from the open to the closed end. There were significant effects of temperature on grain maturity time, thousand grain weight and protein content. The resistance to stretching of the gluten doughs increased with the increasing day temperatures. This was reflected in the proportion of unextractable polymeric proteins (UPP). The results suggest that increases in temperature within this temperature range affect the polymerization of polymeric proteins, giving higher molecular weights, and hence increased Rmax and stronger gluten. The two varieties differed in their response to temperature. In addition, there were seasonal variations in gluten functionality that may be associated with fluctuations in day temperatures between the seasons. [ABSTRACT FROM AUTHOR]

[Display omitted] • The role of thermal inactivation in collagen solubilization during EPH was studied. • Two protases with very different mode of action towards collagen were included. • 180 hydrolysates from different poultry by-products were produced. • Heat assisted solubilization of partly hydrolyzed collagen was assessed. • Sediment removal prior to thermal inactivation is a strategy to tailor hydrolysates. Enzymatic protein hydrolysis (EPH) is an invaluable process to increase the value of food processing by-products. In the current work the aim was to study the role of standard thermal inactivation in collagen solubilization during EPH of poultry by-products. Hundred and eighty hydrolysates were produced using two proteases (stem Bromelain and Endocut-02) and two collagen-rich poultry by-products (turkey tendons and carcasses). Thermal inactivation was performed with and without the sediment to study the effect of heat on collagen solubilization. A large difference in molecular weight distribution profiles was observed when comparing hydrolysate time series of the two proteases. In addition, it was shown that 15 min heat treatment, conventionally used for inactivating proteases, is essential in solubilizing collagen fragments, which significantly contributes to increasing the protein yield of the entire process. The study thus demonstrated the possibility of producing tailored products of different quality by exploiting standard heat inactivation in EPH. [ABSTRACT FROM AUTHOR]

• New SEC -based method was applied for estimation of protein digestibility. • SEC enables quantitative comparisons of protein digestibility in different foods. • The method gives insight into protein solubilization and breakdown during digestion. • The proposed SEC based methodology is reproducible and easy to perform. While the harmonized INFOGEST model provides a physiologically relevant platform for simulated digestion, it needs to be combined with adequate analytical methods to enable quantification and comparison of protein digestibility in different food matrices. We have shown that size exclusion chromatography (SEC) can be used to estimate the proportion of small peptides potentially available for uptake. Combined with determination of total dissolved protein, the % of small peptides per total protein was calculated as a physiologically relevant estimate of protein digestibility (D SEC). Values for D SEC differed for casein (87.6%), chicken mince (72.6%), heated pea protein concentrate (67.8%), bread (63%), beef entrecote (57.7%) and pea protein concentrate (57.8%). In contrast to existing methods (TCA soluble protein, free NH 2 -groups), the proposed SEC based method gives separate insight into the two fundamental processes during protein digestion (solubilization and break-down), while maintaining the ability to rank digestibility of very different food proteins. [ABSTRACT FROM AUTHOR]

• DH% and M w were monitored during enzymatic protein hydrolysis of dairy proteins. • Intercorrelation of DH% vs M w were studied for 60 milk protein hydrolysates. • A PLSR model was developed for prediction of DH% based on molecular weight distribution profiles. • A multivariate model based on dry-film FTIR was developed for dual prediction of DH% and M w. Fourier-transform infrared (FTIR) spectroscopy was applied to predict the degree of hydrolysis (DH%) and weight-average molecular weight (M w) in milk protein hydrolysates. Both DH% and M w are important quality parameters of protein hydrolysates. Measuring these parameters and following their development during proteolytic reactions is therefore essential for process control and optimization in industry. In the present study the intercorrelation and the complimentary nature of these parameters were investigated and a partial least squares regression (PLSR) model was developed for the prediction of DH% from molecular weight distributions. Finally, we developed PLSR models based on dry-film FTIR spectroscopy for the prediction of both DH% and M w. Here spectral changes in the amide region were found to be important for the two calibration models, underlining the advantage of dry-film FTIR measurement. This shows that dry-film infrared spectroscopy is a promising tool for dual prediction of DH% and M w. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate variation in protein content and gluten viscoelastic properties in wheat genotypes grown in two mega-environments of contrasting climates: the southeast of Norway and Minnesota, USA. Twelve spring wheat varieties, nine from Norway and three HRS from Minnesota, were grown in field experiments at different locations in Norway and Minnesota during 2009–2011. The results showed higher protein content but lower TW and TKW when plants were grown in Minnesota, while the gluten quality measured as Rmax showed large variation between locations in both mega-environments. On average, Rmax of the samples grown in Minnesota was higher than those grown in Norway, but some locations in Norway had similar Rmax values to locations in Minnesota. The data showed inconsistent relationship between the temperature during grain filling and Rmax. Our results suggest that the weakening effect of low temperatures on gluten reported in this study are caused by other environmental factors that relate to low temperatures. The variety Berserk showed higher stability in Rmax as it obtained higher values in the environments in Norway that gave very weak gluten for other varieties. [ABSTRACT FROM AUTHOR]