Changes in the composition and size distribution of endosperm proteins from bug-damaged wheats

2004 ◽  
Vol 55 (4) ◽  
pp. 477 ◽  
Author(s):  
D. Sivri ◽  
I. L. Batey ◽  
D. J. Skylas ◽  
L. Daqiq ◽  
C. W. Wrigley

In this study, grain that had been damaged by the bug Eurygaster spp. and/or Aelia spp., plus some undamaged grain, was selected from hard red winter (HRW) wheat. The changes in endosperm proteins were determined by 2-dimensional (2-D) electrophoresis and size-exclusion high-performance liquid chromatography (SE-HPLC). Although some new protein spots and a slight decrease in the staining intensities of some polypeptides were observed in the 2-D map of the bug-damaged sample, other parts of the gels were similar to the sound (control) sample in terms of relative mobilities and intensities of the polypeptide spots. The major difference between bug-damaged and control samples was that a group of polypeptides, presumably HMW-glutenins, shifted to a more basic region of the map. The SE-HPLC patterns of the total proteins extracted from control and bug-damaged samples in SDS-buffer showed that they differed in the size distribution of the polymeric glutenin protein and in their glutenin/gliadin ratios. The solubility of proteins in SDS buffer was greater in the bug-damaged sample. The 'unextractable' polymeric protein (only extractable in SDS-buffer after sonication) (UPP %) was significantly lower in the bug-damaged sample than in the control. The results of 2-D analysis and the decline in the quantity of unextractable proteins in SDS buffer suggest that bug-protease causes dough weakening by degradation of polymeric glutenin, presumably by hydrolysis, and possibly other mechanisms that affect the aggregation of the gluten molecules.

Author(s):  
Pavlína Pečivová ◽  
Iva Burešová ◽  
Jan Hrabě

The influence of different combinations of reducing and oxidising agents (L-cysteine hydrochloride monohydrate + L-ascorbic acid, inactivated dry yeast + L-ascorbic acid, L-threonine + L-ascorbic acid, L-tryptophan + L-ascorbic acid) on the change in the proportion of glutenins, gliadins, albumins, globulins in wheat flour was investigated.Different concentrations of amino acid combinations were added to wheat flour. By means of Size Exclusion High performance liquid chromatography (SE-HPLC), the changes in protein fractions caused by individual concentrations of amino acid combinations were evaluated against the control sample (pure wheat flour).It was detected that the mixture of flour + L-ascorbic acid + L-cysteine hydrochloride monohydrate had the stronger reducing effect than the mixture of flour + L-ascorbic acid + inactivated dry yeast. On the other hand, the mixture of flour + L-ascorbic acid + L-tryptophan had the stronger oxidising effect than the mixture of flour + L-ascorbic acid + L-threonine.


2002 ◽  
Vol 2 (5-6) ◽  
pp. 427-433 ◽  
Author(s):  
J. van Leeuwen ◽  
C. Chow ◽  
R. Fabris ◽  
N. Withers ◽  
D. Page ◽  
...  

To gain an improved understanding of the types of organic compounds that are recalcitrant to water treatment, natural organic matter (NOM) isolates from two drinking water sources (Mt. Zero and Moorabool reservoirs, Victoria, Australia) were separated into fractions of distinct chemical behaviour using resins. Four fractions were obtained from each water source and were organics absorbed to: (1) XAD-8 (very hydrophobic acids, VHA); (2) DAX-4 (slightly hydrophobic acids, SHA); (3) bound to an anion exchange resin (charged organics, CHAR); and (4) not absorbed or bound to resins (neutrals, NEUT). These fractions were then tested to determine the capacity of alum to remove them from water and to correlate this with the character of each isolate. The fractions were characterised by the application of high performance size exclusion chromatography (HPSEC), bacterial regrowth potential (BRP), trihalomethane formation potential (THMFP), pyrolysis gas-chromatography mass spectrometry (Py-GC-MS) and thermochemolysis. The highest removals of dissolved organic carbon (DOC) by alum treatment were in waters spiked with the CHAR fractions while the NEUT fractions were the most recalcitrant. The number average molecular weights (Mn) of DOC of the CHAR fractions before treatment were the highest, whilst those of the NEUT fractions were the lowest. After alum treatment, the Mn of the NEUT fractions were only slightly reduced. Results from Py-GC-MS and thermochemolysis indicate that the NEUT fractions had the highest relative proportion of saccharide derived organic material. Nonetheless, the BRP of waters spiked with the NEUT fractions differed markedly, indicating that organics recalcitrant to alum treatment can vary substantially in their chemical composition and capacity to support microbial growth.


Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 644
Author(s):  
Do-Yeong Kim ◽  
Boram Kim ◽  
Han-Seung Shin

The effect of cellulosic aerogel treatments used for adsorption of four polycyclic aromatic hydrocarbons (PAHs)—benzo[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene [BaP])—generated during the manufacture of sesame oil was evaluated. In this study, eulalia (Miscanthus sinensis var. purpurascens)-based cellulosic aerogel (adsorbent) was prepared and used high performance liquid chromatography with fluorescence detection for determination of PAHs in sesame oil. In addition, changes in the sesame oil quality parameters (acid value, peroxide value, color, and fatty acid composition) following cellulosic aerogel treatment were also evaluated. The four PAHs and their total levels decreased in sesame oil samples roasted under different conditions (p < 0.05) following treatment with cellulosic aerogel. In particular, highly carcinogenic BaP was not detected after treatment with cellulosic aerogel. Moreover, there were no noticeable quality changes in the quality parameters between treated and control samples. It was concluded that eulalia-based cellulosic aerogel proved suitable for the reduction of PAHs from sesame oil and can be used as an eco-friendly adsorbent.


Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 560
Author(s):  
Allah Bakhsh ◽  
Se-Jin Lee ◽  
Eun-Yeong Lee ◽  
Nahar Sabikun ◽  
Young-Hwa Hwang ◽  
...  

This study assessed the effects of Methylcellulose (MC) at different concentrations on plant-based meat analog (PBMA) patties, comprised of commercial texture vegetable protein (C-TVP) and textured isolate soy protein (T-ISP) as key ingredients, and compared to beef patty control. A significantly higher difference was observed in moisture content in control with increasing MC concentration than the C-TVP and T-ISP patties. However, protein varied significantly among three different protein sources, with control had higher protein content than PBMA patties. Crude fiber content recorded higher values in C-TVP as compared to control. Significantly lower pH values were recorded in control than C-TVP and T-ISP respectively. Regardless, with the addition of MC or ingredient PBMA and control patties tend to reduce lightness (L*) and redness (a*) value after cooking. Although control sample before cooking exhibits lighter and redder than PBMA patties (C-TVP and T-ISP). Likewise, water holding capacity (WHC) decreases as the concentration of MC increases (1.5–4%) in control and PBMA patties. Warner-Bratzler shear force (WBSF) and texture profile analysis (TPA), including hardness, chewiness, and gumminess of control, were significantly higher than C-TVP and T-ISP. Consequently, panelists’ in the sensory analysis presented that C-TVP patties containing 3% of MC had better sensory properties than T-ISP. Hence, PBMA patties with C-TVP and incorporation of 3% MC are considered ideal for manufacturing of meat analog as related to control (beef).


2021 ◽  
Vol 170 ◽  
pp. 112529
Author(s):  
N. Cruz ◽  
A.J.N. Batista ◽  
J.M. Cardoso ◽  
B.B. Carvalho ◽  
P.F. Carvalho ◽  
...  

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