Flour Protein Levels Research Articles

Effect of Temperature and Starter Concentration on the Fermentation Process in Making MOCAF

This research aims to determine the optimum conditions with variations in temperature and concentration of Lactic Acid Bacteria (BAL) starter in fermentation in the process of making mocaf flour. Fermentation of cassava is carried out using a fermenter equipped with a thermo controller and tubular heater. Heater is used to increase the temperature connected to the temperature controller (thermo controller) so that the fermentation process runs in optimum conditions and get good quality of mocaf flour according to SNI 7622-2011 standards. The fermentation process was carried out anaerobically with and varying the temperature of 30 and 33°C and the concentration of the lactic acid bacteria starter were 0.06%, 0.12%, 0.18%, 0.24% and 0.3% with fermentation time during 24 hours. The results showed optimum conditions of cassava fermentation at a temperature of 33°C and lactic acid bacteria starter concentration of 0.3% obtained mocaf flour protein levels of 12.87%.

Flour from wheat cultivars of varying hardness produces semi-sweet biscuits with varying textural and structural properties

Semi-sweet biscuits were prepared from flour from wheat cultivars with Single Kernel Characterization System hardness values ranging from 22 to 92. The impact of flour protein level on biscuit properties was compensated for by diluting flour samples of higher protein level with their isolated prime starch fraction. Biscuits prepared from hard wheat flour showed higher fracture stress than their soft wheat flour counterparts. Softer texture mainly resulted from higher porosity, resulting from larger pores. Furthermore, biscuit matrix strength also contributed to biscuit texture. Biscuit texture is strongly affected by wheat hardness and results from the interplay between different hardness-associated flour properties (damaged starch, protein quality, …) as well as from their effect on both biscuit structure and matrix properties.

White Pan Bread and Sugar‐Snap Cookies Containing Wheat Starch Phosphate, A Cross‐Linked Resistant Starch

ABSTRACTPup‐loaf bread was made with 10, 30, and 50% substitution of flour with wheat starch phosphate, a cross‐linked resistant starch (XL‐RS4), while maintaining flour protein level at 11.0% (14% mb) by adding vital wheat gluten. Bread with 30% replacement of flour with laboratory‐prepared XL‐RS4 gave a specific volume of 5.9 cm3/g compared with 6.3 g/cm3 for negative control bread (no added wheat starch), and its crumb was 53% more firm than the control bread after 1 day at 25°C, but 13% more firm after 7 days. Total dietary fiber (TDF) in one‐day‐old bread made with commercial XL‐RS4 at 30% flour substitution increased 3–4% (db) in the control to 19.2% (db) in the test bread, while the sum of slowly digestible starch (SDS) plus resistant starch (RS), determined by a modified Englyst method, increased from 24.3 to 41.8% (db). The reference amount (50 g, as‐is) of that test bread would provide 5.5 g of dietary fiber with 10% fewer calories than control bread. Sugar‐snap cookies were made at 30 and 50% flour replacement with laboratory‐prepared XL‐RS4, potato starch, high‐amylose (70%) corn starch, and commercial heat‐moisture‐treated high‐amylose (70%) corn starch. The shape of cookies was affected by the added starches except for XL‐RS4. The reference amount (30 g, as‐is) of cookies made with commercial XL‐RS4 at 30% flour replacement contained 4.3 g (db) TDF and 3.4 g (db) RS, whereas the negative control contained 0.4 g TDF and 0.6 g RS. The retention of TDF in the baked foods containing added XL‐RS4 was calculated to be >80% for bread and 100% for cookies, while the retention of RS was 35–54% for bread and 106–113% for cookies.

The effects on grain quality traits of a grain serpin protein and the VPM1 segment in southern Australian wheat breeding

Production of wheat of sufficient quality to meet market demands is an ongoing agricultural challenge. Identification and evaluation of alleles of genes affecting quality parameters enables breeders to improve their germplasm by active selection towards specific allele combinations. Using a large dataset obtained from southern Australian wheat breeding programs, and including a relationship matrix in the analysis to minimise bias, we re-evaluated the effects of high- and low-molecular-weight glutenin alleles and puroindoline alleles on the grain quality parameters Rmax, dough extensibility, dough development time, flour water absorption, and milling yield and found that estimated effects were in close agreement with those from earlier analyses without a relationship matrix. We also evaluated, for the first time, the effects on the same quality parameters of 2 alleles (wild-type and null) of a defence grain protein, a serpin located on chromosome 5B. In addition, we assessed the effect of the VPM1 alien segment. The serpin null allele significantly reduced milling yield by ~0.4 g of flour per 100 g of grain milled across different germplasm sources and flour protein levels. In Australian germplasm, the origin of this allele was traced to a 19th Century introduction from India by William Farrer; however other sources, of significance in international breeding programs, were also identified. Our analysis of the effect of the VPM1 segment on quality traits revealed no detrimental effects of its presence on the traits we measured.

Efeito da época, do número de aplicações e de doses de fungicida no controle da giberela em trigo

A giberela é considerada uma doença de infecção floral. Para seu desenvolvimento, são necessárias temperaturas superiores a 20 ºC e períodos de molhamento das espigas maiores do que 72 h durante a antese do trigo (Triticum aestivum). Os objetivos do presente trabalho foram estudar o momento ideal durante a antese para realizar a aplicação de fungicida, o efeito do número de aplicações e de doses de fungicida sobre o controle da doença e sobre a qualidade dos grãos colhidos. Até sete aplicações realizadas durante a antese não erradicaram a doença (controle de 91%). Duas e três aplicações realizadas durante a antese apresentaram controle superior em relação a uma única aplicação. O controle médio dos tratamentos foi de 67% em relação a severidade. O incremento de grãos obtido de 32%, justifica economicamente a aplicação de fungicidas para o controle da doença em plena floração.

Synergistic and Additive Effects of Three High Molecular Weight Glutenin Subunit Loci. II. Effects on Wheat Dough Functionality and End‐Use Quality

ABSTRACTUnderstanding the relationship between basic and applied rheological parameters and the contribution of wheat flour protein content and composition in defining these parameters requires information on the roles of individual flour protein components. The high molecular weight glutenin subunit (HMW‐GS) proteins are major contributors to dough strength and stability. This study focused on eight homozygous wheat lines derived from the bread wheat cvs. Olympic and Gabo with systematic deletions at each of three HMW‐GS encoding gene loci, Glu‐A1, Glu‐B1, and Glu‐D1. Flour protein levels were adjusted to a constant 9% by adding starch. Functionality of the flours was characterized by small‐scale methods (2‐g mixograph, microextension tester). End‐use quality was evaluated by 2‐g microbaking and 10‐g noodle‐making procedures. In this sample set, the Glu‐D1 HMW‐GS (5+10) made a significantly larger contribution to dough properties than HMW‐GS coded by Glu‐B1 (17+18), while subunit 1 coded by Glu‐A1 made the smallest contribution to functionality. These differences remained after removing variations in glutenin‐to‐gliadin ratio. Correlations showed that both basic rheological characteristics and protein size distributions of these flours were good predictors of several applied rheological and end‐use quality tests.

Synergistic and Additive Effects of Three High Molecular Weight Glutenin Subunit Loci. I. Effects on Wheat Dough Rheology

ABSTRACTThe high molecular weight glutenin subunits (HMW‐GS) play an important role in governing the functional properties of wheat dough. To understand the role of HMW‐GS in defining the basic and applied rheological parameters and end‐use quality of wheat dough, it is essential to conduct a systematic study where the effect of different HMW‐GS are determined. This study focuses on the effect of HMW‐GS on basic rheological properties. Eight wheat lines derived from cvs. Olympic and Gabo were used in this study. One line contained HMW‐GS coded by all three loci, three lines were each null at one of the loci, three lines were null at two of the loci and one line null at all three loci. The flour protein level of all samples was adjusted to a constant 9% by adding starch. In another set of experiments, in addition to the flour protein content being held at 9%, the glutenin‐to‐gliadin ratio was maintained at 0.62 by adding gliadin. Rheological properties such as elongational, dynamic, and shear viscometric properties were determined. The presence of Glu‐D1 subunits (5+10) made a significantly larger contribution to dough properties than those encoded by Glu‐B1 (17+18), while subunit 1, encoded by Glu‐A1, made the least contribution to functionality. Results also confirmed that HMW‐GS contributed to strength and stability of dough.

Changes in Disulfide and Sulfhydryl Contents and Electrophoretic Patterns of Extruded Wheat Flour Proteins

ABSTRACTTwin‐screw extrusion of wheat flour and the effects on the flour proteins were studied using flour samples containing 9, 20, and 30% protein. Vital gluten containing 70% protein was used to achieve the flour protein levels. The three flour samples were extruded with a twin‐screw extruder at a combination of processing parameters (exit die temperatures of 120, 140, and 160°C, and screw speeds of 240, 320, and 400 rpm). Increasing extruder exit die temperatures resulted in increased sulfhydryl content of the 9 and 20% protein content flour samples, but appeared to have little or no effect on the 30% protein content flour sample. Similarly, disulfide content decreased, albeit disproportionately, following the same trend. Both sulfhydryl and disulfide contents of extruded samples were lower than those of the nonextruded samples and could imply denaturation of protein, aggregation through intermolecular disulfide bonds, or oxidation during extrusion processing. Total cysteine content of extruded samples decreased by ≈16% relative to nonextruded samples, but otherwise remained almost unchanged among all extruded samples. The loss of total cysteine in extruded samples could represent the generation of hydrogen sulfide, volatile organic compounds, or flavor compounds during extrusion. SDS‐PAGE analysis of total proteins showed a shift from the higher to lower molecular weight regions for certain protein bands. Both depolymerization and protein aggregation occurred at higher shear forces during extrusion.

Investigation of the suitability of Western and Southern Cape wheat flour for production of traditional South African steamed bread

Due to a lack of electrical ovens, it is often found that in the households of the lower-income communities, a home-made steamed bread is prepared in a saucepan on a gas cooker or an open fire. The requirements of flour used to produce high-quality steamed bread are poorly defined. The suitability of Western and Southern Cape wheat for steamed bread production was, therefore, investigated. A marked increase in the nutritive value of steamed bread was reported compared to that of conventionally baked bread, mainly due to the loss of available lysine during conventional baking. Samples of three spring wheat cultivars that were produced during the 1995 and 1996 seasons in the Western and Southern Cape were selected. Flour protein content of these samples varied between 8 and 16%. Flour protein content, Falling Number determinations, gluten content, Mixograph, Alveograph and Rheofermentometer measurements and the 10 g baking test were performed on each of the flours. Steamed and conventionally baked breads were prepared for each cultivar at the four selected flour protein levels, respectively. Total bread volume, weight, height and texture, crust and crumb colour and lysine availability were measured for each loaf of bread. None of the Rheofermentometer measurements correlated significantly with flour protein content or any of the analytical and rheological measurements performed on the flour. All the crust colour parameters of conventionally baked bread correlated significantly with flour protein content. Even though significant correlation was observed for three crust colour parameters of steamed bread, the correlation was lower compared to that of conventionally baked bread. At the four different protein levels, more variation was observed in the elasticity of conventionally baked bread compared to the steamed bread, the texture of the steamed bread was finer and firmer and the crumb was more sticky. The browning reaction occurring in conventionally baked bread results in less available lysine than would be the case for steamed bread. In this study, higher availability of lysine was only the case when steamed bread was produced from high protein flour. Western and Southern Cape spring wheat, irrespective of protein content are, therefore, suitable for the production of good quality steamed bread.

Allelic Variation at Glutenin Subunit and Gliadin Loci, Glu-1, Glu-3 and Gli-1, of Common Wheats. I. Its Additive and Interaction Effects on Dough Properties

Fractionation of glutenin subunits by two-step 1-D SDS-PAGE and of gliadins by standard SDS-PAGE revealed that the parents Halberd and (W1 × MMC)/W1/10 had contrasting alleles at each of the six glutenin subunit (Glu-A3, Glu-B3, Glu-D3, Glu-A1, Glu-B1, Glu-D1) and three gliadin (Gli-A1, Gli-B1, Gli-D1) loci located on their group 1 chromosomes. Thus, a set of 74 recombinant inbred lines homozygous for these loci was chosen from a population of 280 randomly selected F3-derived F7 progeny from crosses between these parents to determine individual and combined effects of alleles at these loci on dough properties as measured by the Brabender Extensograph. The allelic effects were tested at two sites giving widely different flour protein levels, maximum dough resistance (Rmax) and dough extensibility (Ext) values; the effects were comparable between the sites as there were no major site × genotype interactions. Flour protein level generally did not vary significantly amongst the progeny groups based on alleles. On the other hand, progeny carrying alleles c and b at the low Mr glutenin subunit loci Glu-A3 and Glu-B3 had significantly greater Rmax values than the alleles e and c, respectively. Similarly, alleles i (bands 17 + 18) and d (bands 5 + 10) at the high Mr glutenin subunit loci Glu-B1 and Glu-D1 , respectively, gave greater Rmax values than the alleles e (band 20) and a (subunits 2 + 12). Alleles at the other loci (Glu-D3 and Glu-A1) did not give significantly different Rmax values. The effects of individual Glu-3 or Glu-1 alleles on Rmax were largely additive, thus together accounting for about 80% of the variability in Rmax among these progeny. Interactions (epistasis) between different Glu-3 and/or Glu-1 loci also affected Rmax significantly, accounting for about another 10% variation. Based on the alleles analysed, different glutenin subunit loci could be ranked as Glu-D1 > Glu-B1 > Glu-B3 > Glu-A3 > Glu-D3 = Glu-A1 with respect to Rmax . In contrast to Rmax, only 25% of the variation in extensibility could be accounted for by the glutenin alleles. Only Glu-D1 and Glu-D3 loci showed significant effects on this parameter.

YIELDS and BREADING DISPERSION of CHICKEN NUGGETS DURING DEEP-FAT FRYING AS AFFECTED BY PROTEIN CONTENT of BREADING FLOUR

The effects of breading flour protein level on the yield, coating adhesion, and breading dispersion of chicken nuggets during deep-fat frying were investigated. Battered and breaded chicken nuggets with low protein breading flour had a higher (P 0.05) by the protein content of breading flour. the protein content of the flour affected (P < 0.05) the dispersion of breading particles in shortening during deepfat frying. the lower the protein content of the flour, the greater the concentration of suspended breading in the shortening.

The cumulative effect of allelic variation in LMW and HMW glutenin subunits on dough properties in the progeny of two bread wheats

The effects of allelic variation at Gli-A1, GluA3 and Glu-A1 loci coding for gliadins, LMW glutenin subunits and HMW glutenin subunits on dough resistance and extensibility was analysed in 56 F2-derived F6 families from a cross between bread wheats MKR(111/8) and 'Kite'. Extensograph data from two sites giving widely different flour protein levels (approximately 7% and 14%) revealed that the Glu-A3m and Glu-A1b alleles were associated with larger effects on dough resistance and extensibility than the null alleles Glu-A3k and GluA1c, respectively, and moreover, their effects were additive at both protein levels. The effect of the LMW glutenin allele Glu-A3m on both dough resistance and dough extensibility was relatively larger than that of the HMW glutenin allele Glu-A1b at both sites. Variation at the Gli-A1 locus did not appear to contribute towards dough strength. The results also showed the large effect of flour protein content on dough properties.

The influence of high-molecular-weight subunits of glutenin from Triticum tauschii on flour quality of synthetic hexaploid wheat

Peak dough development times, test-bake loaf volumes and levels of non-polar and polar lipids were measured for flours from newly-synthesised hexaploid wheats obtained from crosses between Triticum turgidum conv. durum cultivars and T. tauschii accessions differing in high-molecular-weight (HMW) glutenin subunits. Synthetic hexaploids possessing subunits 5 and 10 of glutenin had longer peak dough development times and higher loaf volumes when compared with subunits 2 and 12. Using chloroform extraction, a higher ratio of non-polar to polar lipids was observed with subunits 2 and 12 compared with 5 and 10 after correcting to a constant flour protein level. The influence of the newly-identified HMW subunits combinations 2, T1, T2 and subunits 2·1, 10·1 on flour and dough properties are also reported.