Starch Flour Research Articles

Wheat batter physical properties as influenced by starch/flour types and egg contents

Batter liquid–solid phase interactions can play a critical role in determining the functionality, including adherence, appearance and texture of end use coated product. Batter chemical composition is a key factor affecting batter characteristics. The effect of substituting wheat flour with fractions of rice flour, native corn starch, modified waxy corn starch, tapioca starch and lupine flour ranging from 26 to 56% of the solid phase and egg levels ranging from 6 to 35% of the liquid phase on the rheological properties of batter systems was studied. Results indicated that lupine flour had the greatest water holding capacity (WHC) ranging from 93.9 to 119.3% of various lupine flour percent to egg levels used. Flow behaviour index of batter flour treatments ranged from 0.91 to 1.87; values that were significantly (P < 0.05) greater than a 100% control wheat flour. Consistency coefficient of treatments ranged from 0.01 to 0.37 mPa sn; values that were significantly lower than wheat flour (i.e., 5 mPa sn). Egg level used in this study had minimal effect on treatment rheological properties. The changes in WHC and viscoelastic properties of treatments were attributed to changes in protein and fibre contents and structure as a result of replacing wheat flour with starch/flour. Protein–starch–lipid matrix formation and variation in water absorption kinetics of treatments most probably wrought batter functionality. The increase in pasting properties with the increase in starch/flour contribution suggested an increased contribution of starch in forming a net effect of batter treatments pasting viscosities. Results of this study provide vital information for the potential use of starch types to enhance the rheological properties of coating applications including adhesion and water holding capacity of substituted batter treatment.

Physico-chemical properties, phytochemicals and DPPH radical scavenging activity of supercritical fluid extruded lentils

A powder blend comprised of lentil flour and pre-gelatinized potato starch was processed using supercritical fluid (carbon dioxide) extrusion (SCFX). The blend was extruded at temperature of 95–99.5 °C and screw speeds of 40, 80 and 120 rpm. The physical properties of the extruded products such as porosity, rehydration rate, expansion ratio, and crispness—improved as the screw speed increased. Furthermore, the density, water solubility index, brittleness, and hardness of the products decreased as the screw speed increased. SCFX increased the transition temperature of starch and protein in lentil flour. Increased screw speed led to increased gelatinization in the starch. Unlike traditionally cooked lentils, no retrogradation of starch was observed for the extruded red lentil products stored at room temperature for 60 days. Compared to raw lentil, SCFX increased the total phenolic and DPPH radical scavenging activity of lentils by 30% and 18%, respectively. In addition, SCFX decreased the trypsin inhibitor content in the lentil flour. Higher screw speeds led to a greater reduction in the trypsin inhibitor content. The SCFX process rendered red lentil flour into a snack-type whole grain product with a more balanced nutritional and antioxidant composition.

Dough rheology and physicochemical properties of steamed buns fortified with cross-linked rice starch

Although fibre is associated with numerous health effects, daily fibre consumption is less than recommended. Fibre-enriched food is desirable to overcome this problem and resistant starch (RS) has potential as fibre ingredient. The objective of the research was to study the effect of cross-linked (CL) rice starch (RS type 4) at different levels (0%, 15% and 30%) on dough rheology, physicochemical and sensory acceptance of steamed bun. CL rice starch was produced by cross-linking rice starch with combination of 12% sodium trimetaphosphate and sodium tripolyphosphate for 3h at 45°C under alkaline condition. The dough of steamed bun was characterized by Farinograph and Extensograph, whereas cooked steamed bun was characterized by total dietary fibre, protein, moisture, textural properties, colour and sensory acceptance. Incorporation of CL rice starch in wheat flour lowered the strength, extensibility and quality of dough. The quality of dough was positively correlated with the protein content, indicating lower gluten formation in fortified SB. Total dietary fibre of steamed bun increased significantly with increasing CL starch in the order: 30CL (2.44%) > 15CL (1.33%) > 0CL (0.75%). Hardness and yellowness of steamed bun incorporated with CL rice starch reduced significantly. SB with 15% CL rice starch showed similar sensory acceptability with control SB. The study suggests that CL rice starch at 15% is suitable to increase fibre in steamed bun with little effects on the appearance and sensory attributes.

Comparison of Flour Starch Properties in Half‐Sib Families of Opaque‐2 Maize (Zea mays L.) from Argentina

Since the discovery of the o2 mutation in maize, many studies have reported the characterization of the protein quality of opaque‐2 genotypes. However, few have reported the properties of their starch. The objective of this study was to characterize flour starch properties of 12 half‐sib families of opaque‐2 maize from Argentina. Chemical composition and thermal and pasting properties of whole grain flour were determined. Nonopaque genotypes were used as a control. Starch content of opaque‐2 genotypes did not show significant differences compared with nonopaque genotypes, yet amylose content was significantly lower. A high variability in pasting and thermal properties was observed in genotypes. Opaque samples showed a significantly higher peak viscosity and a lower pasting temperature compared with nonopaque samples, probably owing to larger and less compact starch granules in the floury endosperm. The higher the gelatinization enthalpy of opaque‐2 genotypes was, the lower the amylose content in relation to nonopaque varieties. Two retrogradation endotherms were observed in DSC analysis: one corresponding to amylopectin crystallization and the other to melting of amylose‐lipid complex. Both enthalpies were considered total starch retrogradation (ΔHRT). A wide range of variation was obtained in ΔHRT in opaque‐2 genotypes, but no significant differences between opaque and nonopaque genotypes were observed. The differences in starch properties found in this study would make it possible to identify opaque‐2 families with particular characteristics for the development of starchy food items adapted to specific processing traits.

Using near infrared spectroscopy to determine moisture and starch content of corn processing products

Due to the rapid development of the corn-to-ethanol industry, the demand for process monitoring has led to the gradual substitution of traditional analytical techniques with fast and non-destructive methods such as near infrared spectroscopy. In this study, the feasibility of using Fourier transform–near infrared technology as an analytical tool to predict operational parameters (dry solids, starch, carbohydrate, and ethanol content) was investigated. Corn flour, liquefied mash, fermented mash, and distiller’s dried grains with solubles were selected to represent the feedstock, two intermediate products, and one primary co-product of corn-to-ethanol plants, respectively. Multivariate partial least square calibration models were developed to correlate near infrared spectra to the corresponding analytical values. The validation results indicate that near infrared models can be developed that will predict various parameters accurately (root mean square error of prediction: 0.16–1.14%, residual predictive deviation: 3.0–6.3). Measurement of starch or carbohydrate content in corn flour or distiller’s dried grains with solubles is challenging due to low accuracy of wet chemistry methods as well as sample complexity. The study demonstrated that near infrared spectroscopy, a high-throughput analytical technique, has the potential to replace the enzymatic assay.

The adsorption of α-amylase on barley proteins affects the in vitro digestion of starch in barley flour

The conversion of barley starch to sugars is a complex enzymic process. Most previous work concerned the biotechnical aspect of in situ barley enzymes. However, the interactions among the macromolecular substrates and their effects on enzymic catalysis has been little examined. Here, we explore the mechanisms whereby interactions of protein and starch in barley flour affect the kinetics of enzymatic hydrolysis of starch in an in vitro system, using digestion rate data and structural analysis by confocal microscopy. The degradation kinetics of both uncooked barley flour and of purified starches are found to be two-step sequential processes. Barley proteins, especially the water-soluble component, are found to retard the digestion of starch degraded by α-amylase: the enzyme binds with water-insoluble protein and with starch granules, leading to reduced starch hydrolysis. These findings are of potential industrial value in both the brewing and food industries.

Quantitative analysis of total starch content in wheat flour by reaction headspace gas chromatography.

This paper proposed a new reaction headspace gas chromatographic (HS-GC) method for efficiently quantifying the total starch content in wheat flours. A certain weight of wheat flour was oxidized by potassium dichromate in an acidic condition in a sealed headspace vial. The results show that the starch in wheat flour can be completely transferred to carbon dioxide at the given conditions (at 100°C for 40min) and the total starch content in wheat flour sample can be indirectly quantified by detecting the CO2 formed from the oxidation reaction. The data showed that the relative standard deviation of the reaction HS-GC method in the precision test was less than 3.06%, and the relative differences between the new method and the reference method (titration method) were no more than 8.90%. The new reaction HS-GC method is automated, accurate, and can be a reliable tool for determining the total starch content in wheat flours in both laboratory and industrial applications. Graphical abstract The total starch content in wheat flour can be indirectly quantified by the GC detection of the CO2 formed from the oxidation reaction between wheat flour and potassium dichromate in an acidic condition.

Multi-scale structures and pasting characteristics of starch in whole-wheat flour treated by superfine grinding

The multi-scale structures and pasting properties of starch in WWF were investigated after superfine grinding. Five particle size distributions of WWF and their corresponding starch were obtained. The grinding process reduced the particle size of WWF and starch. However, a slight increase of fragments from starch granules was observed with enhanced grinding strength because of the small decrease in starch particle size and the existence of other WWF components that undertook some of shearing force and friction during grinding. A prominent reduction in starch crystallinity was resulted due to the destruction of crystalline structure by grinding. Small-angle X-ray scattering analyses indicated the disordering in starch semi-crystalline lamellae with thinner lamellae thickness. Additionally, the 13C Nuclear Magnetic Resonance spectra demonstrated the alterations in starch chain conformation by varying peak areas of starch carbons (C1 and C4). Along with these structural changes, Starch pasting characteristics showed substantial variations, indicating decreased viscosities and higher pasting stability. The results suggest that the grinding treatments influenced the structures and pasting properties of starch even at a non-separated state, the changes in starch structures were related to the variations in starch gelatinization characteristics.

Comparison of different extraction methodologies for the analysis of volatile compounds in gluten-free flours and corn starch by GC/QTOF

Gluten-free bakery products usually exhibit weak aroma. Their main constituents are flours and starches, which contain aroma precursors but can also contribute additional volatiles in low concentrations. Static headspace (SHS), solid-phase microextraction (SPME) and solvent-assisted flavour evaporation (SAFE) coupled to GC/QTOF were compared for their efficacy in the analysis of volatiles in corn starch. SPME-GC/QTOF was selected as the most suitable methodology based on the number of detected compounds, LODs, repeatability as well as simplicity. It was successfully applied for the quantification of volatiles in corn starch and qualitative comparison of different gluten-free flours. Hexanal, 3-methyl-1-butanol, 1-pentanol, 1-octen-3-ol, acetic acid, furfural, benzaldehyde, (E)-2-nonenal, phenylethyl alcohol and short-medium chain acids were found in all the flours and corn starch. Quinoa flour and corn starch showed the highest contents of pyrazines, terpenes and esters, while teff, buckwheat and rice flours presented the highest contents of 3/2-methyl-1-butanol, acetoin and organic acids.

Wheat dough syruping in cold storage is related to structural changes of starch and non-starch polysaccharides

Even though the refrigerated dough industry is growing quickly due to the convenience and freshness of refrigerated dough over a prolonged storage period, dough syruping, which is a brownish liquid that leaches out from dough during the storage, is a quality-diminishing factor that needs to be resolved. The objectives of this study were to understand dough syruping and how it is related to structural changes in water-soluble arabinoxylan (WS-AX) and starch in wheat flours during refrigeration as well as to prevent syruping by applying exogenous cell wall polysaccharides. Dough syruping increased to 6.5, 6.9, and 17.2% in weak, strong, and jopoom wheat flours, respectively, after a 35-day storage period. The endoxylanase activity of jopoom wheat flour was substantially greater compared to other commercial flours, but the activity of this flour did not change over the whole cold storage period. The molecular size reduction of WS-AX was inversely related to the degree of dough syruping. The addition of β-glucan, carboxymethylcellulose, and xylan effectively reduced syrup formation in jopoom wheat flour dough.

In vitro starch digestibility of rice flour is not affected by method of cooking

This study evaluated the effects of different cooking methods on in vitro starch digestibility of three rice varieties. Results from differential scanning calorimetry and X-ray diffraction of cooked rice flours showed that rice starch was completely gelatinized after cooking. The overall paste viscosities of cooked indica hybrid flour (IHF) and japonica flour (JF) were lower than those of their corresponding raw flours. However, cooked waxy flour (WF) showed much higher paste viscosities than raw flours, especially the viscosity at the start of RVA testing. Cooking increased greatly the rate and extent of starch digestion of IHF and JF, but had a small effect on WF. There were small differences in rate and extent of starch digestion of rice after cooking under various conditions. Cooking methods were found to have little effect on in vitro starch digestibility of rice. Viscosity of the gelatinized waxy starch matrix affected in vitro starch digestibility. This study enables us to gain a better understanding of cooking effects on in vitro digestibility of starch in rice flour.

Evaluation of Soybean–Navy Bean Emulsions Using Different Processing Technologies

In this study, an innovative emulsion made from soybean and navy bean blends of different proportionalities was developed. In addition, two processing methods were used: traditional cooking and jet-cooking. The physical attributes and storage stability were measured and compared. This study found that the high content of starch and fiber in navy bean flour contributes to the increase in viscosity of the emulsions, at both room and refrigeration temperatures, as the proportion of navy bean flour in the blends increased. The steam jet-cooked emulsions with higher soybean content has better shelf life stability, smaller particle size, higher fat, lower starch, and lower viscosity, whereas the traditional kettle cooking method is better in reducing anti-nutritional components. No significant difference was found between the two cooking methods in terms of nutritional contents in the emulsions, such as protein, crude fat, and total starch. The traditional kettle cooking, with its longer cooking time, seems to reduce more trypsin inhibitor in the emulsions than those prepared with the steam jet-cooking. This exploratory study is the first to report soybean–navy bean beverage prototypes having desirable nutritional value and the potential for functional beverage market.

A switch point model for high-resolution moisture absorption isotherms of raw and pregelatinized starches

The goal of this work was to find or create a simple model of the experimental high-resolution water absorption isotherms, determined with the dynamic dewpoint isotherm method (DDI) for different forms of starch powder. The samples used were rice and cassava starches and their 1:1 mix, each in raw and pregelatinized forms. The adsorption isotherms were measured at both 25 and 35 °C temperatures for the water activity range 0.2–0.9. The results showed that the modern DDI method provided densely measured isotherms with consistent characteristics. In particular, a linear zone in the adsorption isotherms of starch powders can be identified and its extent estimated. It is also subjectively clear with the DDI resolution across all the samples tested. Aside from smallish distinction between raw and pregelatinized cases, the starches had very similar isotherms, which might represent a “generic starch flour isotherm”. This shape was very well fit by an initial linear segment and a final curved segment, with the critical transition at the switch point. The transition point results indicate that pregelatinization increases the demands on water barrier properties of the packaging.

Development of groundnut shells and bagasse briquettes as sustainable fuel sources for domestic cooking applications in Uganda

In this study groundnut shells and bagasse briquettes from agricultural wastes were developed with cassava and wheat starch binders using low pressure and high pressure techniques. In the low pressure technique, briquettes were produced after carbonization of groundnut shells and bagasse. The resulting bio-char was mixed with 30, 50, 70 and 90 g of cassava and wheat flour starch binder for each 1000 g of groundnut shells and bagasse bio-char. Groundnut shell briquettes were also developed under high pressure (230 MPa) using groundnut shells (1000 g) without a binder, groundnut shells (1000 g) with cassava flour starch binder (250 g) and groundnut shells with wheat flour starch binder (250 g). Thermo-physical properties of the briquettes were determined using thermo-gravimetric analysis. A Bomb calorimeter was used to determine the higher heating values of the briquettes. Thermal characteristics were determined by observing the flame temperature during combustion. The mechanical integrity of the briquettes was determined using the drop test method. The higher heating values for groundnut shell and bagasse briquettes developed using low pressure techniques were between 21 and 23 MJ/kg for both cassava and wheat starch binders. The results were all above the 16 MJ/kg average recorded for non-carbonized groundnut shell briquettes developed under high pressure.

Starch Product of Wild Plants Species Jalawure (Tacca leontopetaloides L.) Kuntze as The Source of Food Security in The South Coastal West Java

Majority of people of South coast of West Java, from Sukabumi, Cianjur, Garut are fishermen. Natural conditions are very dry and the area of land for agriculture, particularly rice cultivation is minimal. So that the condition of the society is more directed to high enough levels of food insecurity. Because coastal areas tend to have a longer dry season from rainfall. Results of research conducted in the years 2013 - 2016 in the area of Pelabuhan Ratu, Cidaun (Cianjur), Coastal area of Jayanti, Ranca Buaya, Mekar Mukti, and along the coast until Pameungpeuk, Leuweung Sancang, is known that jalawure plant which grows wild at South-coast region of West Java is precisely the alternative solution to address food insecurity. The results of the starch flour is a source of carbohydrate that is high enough to be used as a substitute for rice and wheat. Another potential source of jalawure nutrition is also recommended for diabetics consumption.

Ibrahim – the cassava starch processor

Subject area AgriBusiness entrepreneurship Study level/applicability Post-graduate and executive education classes in agribusiness: MBA, Executive Education programmes for senior managers; entrepreneurial studies and workshops for SMEs. Case overview This case study is centred on Ibrahim, a businessman in Tanzania, who decided to start a business to process and sell cassava starch flour. Following a market survey, he realized that the demand for cassava starch surpassed the supply and planned to bridge this gap. To realize his business idea, he applied for and received a loan from an investment bank (Tanzania Investment bank), with which he bought processing machines and some acres of land for the cultivation of the crop. Unfortunately, he encountered a major setback because the sub-standard processing machine he bought stopped working after one week. He could neither repair his equipment nor buy new ones because the bank refused to extend his loan facility. Ibrahim was also having problems meeting a huge international and local demand for his cassava because of inadequate supply of cassava by local farmers. Expected learning outcomes This paper aims to understand the entire cassava value chain, which is made up of three major players: growers, processors and end-users; to understand the business case for opting to focus on one of the three areas, what arguments could be given for being a grower, a processor or an end-user; to understand that there are different types of end-user products: cassava starch flour, high-quality cassava flour, both of which can come from an intermediate product called “grates”; to understand the reason for the paradox, that there is (potentially) a high demand for cassava flour locally, and yet these end-users are not yet willing to patronize the local market because supply is low, and supply is low, not because farmers cannot produce more, but simply because they are not processing more – why is this?; to understand that the “processing” stage seem to be the rate-limiting-stage in the cassava starch production value chain – how can this process be improved?; to understand the case for aggregating local farmers into cooperatives to produce enough cassava roots to feed the need of industrial processors, and aggregators can also collect and pre-process into “grates” before selling to industrial processing companies; and to understand the importance of locating processing plants close to the farms. Supplementary materials Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes. Subject code CSS 3: Entrepreneurship.

Evaluation of mageu-based gluten-free bread loaf characteristics

Gluten-free bread (GFB) has poor quality attributes compared with wheat bread. Coeliac disease is an autoimmune disease triggered by gluten consumption. Mageu, a traditional beverage, was used in GFB with hydrocolloids, sorghum, soybean flour and maize starch. Quality parameters included specific volume (SV), loaf height, bake loss, crumb firmness, firming rate, onset of mould growth, sensory attributes: texture, crumb colour, crust colour, flavour and overall acceptability.Treatments included: control, with cooked maize flour (C1); bread with mageu and without hydrocolloids (C2); breads with mageu and the following − xanthan gum (XG); guar gum (GG); hydroxypropylmethylcellulose (HPMC) and carboxymethyl cellulose (CMC). Brown wheat bread (BB) was tested in texture measurement comparisons.Hydrocolloids optimized at 1.7% CMC; 0.5% XG; 1.7% GG and 0.8% HPMC (w/w in dough). CMC had significantly (p-value < 0.05) higher SV of 3.34 cm3/g; highest loaf height at 5.26 cm and GG the lowest bake loss (10.35%).Texture measurements indicated treatments were firmer than BB. Hydrocolloids increased bread firmness: GG being the firmest and C2 with the lowest firming rate.HPMC had significantly (p-value < 0.05) more mould free days than C1 and XG.Sensory evaluation indicated CMC was liked for flavour (6.70), crust colour (7.23), XG for texture (6.41), crumb colour (7.18) and overall acceptability (6.89).

Biophysical features of cereal endosperm that decrease starch digestibility

The influence of the physical structure of cereal endosperm on the natural structural integrity (intact cells) and starch bioaccessibility of the resultant flours was studied using maize as example. Endosperm hardness, defined by its intracellular (protein matrix) and extracellular (cell walls) constituents, affected the granular and molecular damage of the starch of the resultant flours leading to higher digestibility of raw hard than soft endosperm flours, but comparatively lower digestibility after cooking. After milling, hard endosperm possessed more damaged starch (radial splitting of amylopectin clusters) in the periphery of the resultant particles that increased in vitro starch digestibility of raw flours. Conversely, the hard endosperm plant tissue matrix significantly limited water availability and heat transfer on starch gelatinisation, thereby decreasing the digestion rate after hydrothermal processing (in particle size flours >80μm). This study provides a unique mechanistic understanding to obtain cereal flours with slow digestion property for commercial utilisation.

Study on the Change in Powder Properties of Rice Flour by Different Milling Processes.

The aim of this study was to clarify the change in the powder properties of rice flour depending on the milling process. Rice flour samples, which have gradual mechanical shock properties, were prepared using different milling methods. Furthermore, the correlation between the starch damage, owing to mechanical shock, and powder properties of rice flour was investigated. The particle size was changed gradually through each milling process; however, the change did not clearly correlate with starch damage. The results of the X-ray diffraction (XRD) pattern of nongelatinized samples showed the typical A-type structure of starch. The crystal structure of starch in rice flour may change to a disorder state with the progress of milling; thus, in this study, instead of crystallinity, we considered the disorder index (DI) calculated from the XRD intensity of samples. Relationship between DI and starch damage was confirmed with R2 = 0.923. Therefore, the mechanical shock caused by the milling process contributes to the crystal state of starch. The parameter qm calculated from the Guggenheim-Anderson-de Boer (GAB) equation of each sample corresponded to the DI. This result suggested that the sorption site of rice flour decreased, and a positive correlation was observed between the parameter K and DI. Thus, the interaction between the rice flour and water molecules weakened because of the mechanical shock. In addition, the use of a SEM image supports the insight that the change in parameter K may reflect the structural change in the solid phase. These results demonstrated that the change in powder properties of rice flour caused by mechanical shock of the milling could evaluate quantitatively.

Production of Glucose Sweetener by Simple Single- Step Hydrolysis of Native Cassava Root Starch

Abstract. In conventional practice, starch is extracted and purified from a native source prior to glucose production using two steps: liquefaction and saccharification. Sequential protocols, liquefaction, and starch extraction and purification necessitate high-energy process conditions, material handling equipment, and other substantial cost inputs. In this work, native starch in ground fresh cassava root pulp and cassava flour was subjected to low-energy, simple single-step enzymatic hydrolysis at 37°C and 60°C for glucose production. Commercial purified cassava starch was similarly treated for comparison. Cassava root pulp reached a maximum of 30% starch conversion to glucose within 4 h of hydrolysis at 60°C and a maximum of 55% conversion within 96 h at 37°C. Cassava flour yielded mixed results, with slightly less conversion than root pulp at 60°C, reaching only 27%, but outperformed root pulp at 37°C, reaching 72% conversion. Purified cassava starch yielded 96% and 100% conversions at 60°C and 37°C, respectively. At 37°C, the reaction rate constants were 0.023 h-1, 0.021 h-1, and 0.025 h-1, respectively, for cassava root pulp, flour, and purified cassava starch, while at 60°C, the reaction rate constants were 0.816 h-1, 1.230 h-1, and 1.102 h-1, respectively. Activation energy for the substrates was similar at 134.6 kJ mol-1 for root pulp, 157.4 kJ mol-1 for flour, and 143.1 kJ mol-1 for purified starch. Keywords: Cassava root, Cassava starch, Enzymes, Glucose, Reaction kinetics, Synergistic enzymatic hydrolysis.