Roller Milled Fractions Research Articles

Comparison of distribution and physicochemical properties of β-glucan extracted from different fractions of highland barley grains

Highland barley grains were roller-milled to produce five different fractions (B-1, B-2, B-3, B-4, and B-5). The distribution and physicochemical properties of β-glucans from five roller-milled fractions were investigated. The B-4 fraction contained the highest concentration of β-glucan (4.40%), and the outermost bran (B-1) had the lowest β-glucan content (1.01%). Besides, β-glucans from inner core B-5 (BG-5) had higher Mw (6.482 × 105 g/mol), whereas β-glucans from outer bran B-1 (BG-1) showed lower Mw (5.859 × 104 g/mol) than those from other fractions. Accordingly, the viscosity of BG-5 was highest (0.038-0.365 Pa·s), and the water solubility index of BG-1 was highest (50.43–90.71%). BG-5 showed stronger foam stability and emulsifying properties but weaker foaming capability, while BG-1 exhibited stronger foaming capability. The foaming capability and emulsifying properties of β-glucan samples were better under the neutral condition (pH = 7). The foam capabilities of all β-glucan samples displayed higher values at 65 °C, and emulsifying properties exhibited higher values at 45 °C. This study is expected to promote the application of highland barley β-glucans in food industry.

Functional properties of roller mill processed fenugreek fractions

The present study was carried out to investigate functional properties of roller milled fenugreek fractions. The coarse husk (CH) and fine husk (FH) were found rich in dietary fiber content and flour fraction (FL) rich in protein and oil. Bulk density of the milled fractions showed that the embryo fraction is lighter (0.51 g mL−1), and husk fraction is heavier (0.84 g mL−1) than the whole fenugreek flour (WFF)). CH and FH had highest water absorption capacities with values of 17.44 and 15.42% respectively. The highest apparent viscosity was recorded by CH while FL fraction observed lowest. All samples had a non-Newtonian behaviour at all tested temperatures. The measurement of foaming and emulsion properties of WFF and roller milled fractions showed that they were greatly affected by pH levels. The minimum values of emulsion properties were obtained at pH 4 which was nearer to isoelectric point of the protein.

Brans of the roller-milled barley fractions rich in polyphenols and health-promoting lipophilic molecules

Three different roller-milled fractions namely bran, middlings, and flour of five commonly grown Irish barley varieties were investigated for the presence of β-glucan, polyphenols, and health-promoting lipophilic molecules. β-glucan was predominantly located in barley middlings. Polyphenols, as indicated by total phenolic content and the antioxidant activities, were abundant in the outermost bran fractions of barley. Similarly the health-promoting lipophilic molecules including phytosterols, unsaturated fatty acids, and tocols were most abundant in the barley bran fraction. However, the distribution of individual polyphenols and lipophilic compounds varied within the grain; for example ferulic acid and procyainidin C were not detected in flour fraction. Principal component analysis (PCA) clearly indicated a higher distribution of most bioactive molecules in bran as compared to middlings and flour fractions. The PCA also established possible correlations between the five barley varieties and their fractions based on their clustering in the plot.

A study on rheological characteristics of roller milled fenugreek fractions.

Fenugreek seeds were fractionated by roller milling to get various fractions. The roller milled fractions and whole fenugreek flour (WFF) were evaluated for the flow behavior and time-dependent flow properties using a rotational viscometer at the temperatures of 10-60 (0)C. The samples subjected to a programmed shear rate increase linearly from 0 to 300s(-1) in 3min and successive decrease linearly shear rate from 300s(-1) to 0 in 3min. The roller milled fractions and WFF paste exhibited non-Newtonian pseudoplastic behavior. Difference in hysteresis loop area was observed among the roller milled fractions and WFF, being more noticeable at lower temperatures. Power law and Casson models were used to predict flow properties of samples. The power law model described well the flow behavior of the roller milled fractions and WFF at temperatures tested.Except flour (FL) fraction, consistency coefficient, m, increased with thetemperature both in the forward and backward measurements. The roller milled fractions and WFF exhibited rheopectic behavior that increased viscosity with increasing the shear speed and the temperature. For all the sample tested, initial shear stress increased with increase in shear rate and temperature.

Rheological, physico-sensory, nutritional and storage characteristics of bread enriched with roller milled fractions of black gram (Phaseolus mungo L.).

Black gram grains were fractionated using roller flour mill. Effect of combination of additives (CA) namely dry gluten powder, sodium stearoyl-2-lactylate, fungal α-amylase on the rheological and bread making characteristics of wheat flour partly replaced with roller milled fractions of black gram was studied. With increase in the addition of straight run flour (SRF), protein rich fraction (PRF), protein and fiber rich fraction (P&FRF) from 0 to 20%, fiber rich fraction, FRF (0-15%), the farinograph water absorption increased and dough stability decreased; amylograph pasting temperature increased and peak viscosity decreased; bread volume decreased and crumb firmness value increased indicating adverse effect of these fractions on the rheological and bread making characteristics of wheat flour. Sensory evaluation showed that breads were acceptable only up to the level of 15% for SRF, PRF & P&FRF and 10% for FRF. However, when CA containing dry gluten powder, sodium stearoyl-2-lactylate and fungal α-amylase was incorporated the overall quality of the products improved. Use of these fractions increased the protein and fiber contents of bread by 1.24-1.66 and 1.48-3.79 times respectively. The results showed that possibility of utilising roller milled black gram fractions along with CA to improve the taste, texture and nutritional quality of bread.

Roller milling process for fractionation of fenugreek seeds (Trigonella foenumgraecum) and characterization of milled fractions.

The fenugreek seed is the richest source of soluble and insoluble fiber and also known for its medicinal and functional properties. The major objective of this present study is fractionation of the fenugreek by roller milling method and characterization of roller milled fractions. The effects of moisture conditioning on fenugreek roller milling were studied using standard methods. The results observed were increase in coarse husk from 33.75-42.46% and decrease in flour yield from 49.52-41.62% with increase in addition of moisture from 12-20%. At 16% conditioning moisture, the yield of coarse husk was 40.87% with dietary fiber and protein content of 73.4% and 6.96% respectively. The yellowness value (b) for the coarse husk (29.68) found to be lowest at 16% conditioning moisture compared to the other coarse husk samples, showing maximum clean separation. The fiber fractions showed the viscosity of 6,392 cps at 2%w/v concentration. The flour fraction was higher in protein (41.83%) and fat (13.22%) content. Roller milling process of fenugreek was able to produce > 40% of coarse husk with 73.4% dietary fiber (25.56% soluble & 47.84% insoluble) and > 48% flour with 41.83% protein content, where as the whole fenugreek contained 22.5% protein & 51.25% dietary fiber. Thus roller milling has proved to be a valuable method for the fractionation of fenugreek to obtain fiber and protein rich fractions.

Development of protein and fiber enriched breads by supplementation of roller milled fractions of green gram

The different roller milled fractions from green gram such as straight run flour (SRF), protein rich fraction (PRF), fiber rich fraction (FRF) and protein and fiber rich fraction (P&FRF) were replaced with wheat flour for the preparation of breads. The Farinograph water absorption increased and dough stability decreased by replacement of SRF, PRF, FRF and P&FRF. The bread volume decreased and crumb firmness value increased showing adverse effect of roller milled green gram fractions on the volume and texture of bread. Sensory evaluation of bread showed that the 15 % substitution of SRF, PRF & P&FRF and 10 % substitution of FRF produced acceptable quality bread. Addition of combination of additives (CA) like dry gluten powder, sodium stearoyl-2-lactylate and fungal α-amylase brought about significant improvement in the dough strength and overall quality of the bread. The results showed that bread with improved nutritional quality and acceptable taste could be produced by adding separately 15 % SRF, PRF, P&FRF and 10 % FRF with CA.

Roller milling fractionation of green gram (Vigna radiata): optimization of milling conditions and chemical characterization of millstreams.

In the view of recent growing interest in utilization of grain fractions as food ingredient, present investigation was carried out to evaluate the roller milling potential of green gram. The effect of conditioning moistures on green gram roller milling were studied. The results showed decrease in flour yield from 85.56 to 58.74% with increase in conditioning moisture from 10 to 16%. Higher yield of flour was observed from the first (C1), second (C2) and third (C3) reduction passages; whereas, the first (B1), second (B2) and third (B3) break passages produced less flour. The distribution of protein, dietary fiber, ash and fat in different flour streams and by-products from roller milled fractions of green gram showed wide variation. The protein content increased with increasing numbers of breaks and reductions in the flour streams. The highest protein content of 30.16% was found in bran duster flour and lowest (11.32%) in fine seed coat. The protein content of break streams was found lower than reduction streams. The dietary fiber content of coarse seed coat was highest (71.17%) followed by the fine seed coat (57.22%). The microstructure studies of milled fractions of green gram showed more deformed and damaged starch granules in reduction flour streams than break flour streams.

The Properties of β-Glucans from Different Fractions of Hull-Less Barley

Crude β-glucans were prepared from hull-less barley roller-milled fractions by aqueous sodium carbonate ( pH10). β-Glucan preparations from hull-less barley roller-milled fractions had high purity (90.88-95.04%). The Mw of β-glucan preparations from roller-milled fractions was ranging from 117,600 to 852,400 g/mol, For the same hull-less barley cultivar, β-glucan from flour had higher Mw than shorts and bran, and β-glucan preparations from bran had the lowest Mw.

Distribution and Molecular Characterization of β-Glucans from Hull-Less Barley Bran, Shorts and Flour

Six hull-less barley cultivars widely grown in China were roller-milled to produce bran, shorts and flour fractions. The distribution and molecular characteristics of β-glucans from the three roller-milled fractions were investigated. The β-glucan contents in the six hull-less barley cultivars varied from 4.96% to 7.62%. For all the six cultivars, the shorts fraction contained the highest concentration of β-glucan (8.12–13.01%), followed by bran (6.15–7.58%) and flour (2.48–2.95%). Crude β-glucans were prepared from the three roller-milled fractions using aqueous sodium carbonate (pH 10). These preparations contained 45.38–71.41% β-glucan, 10.81–17.26% arabinoxylan, 2.6–9.6% protein, 2.7–9.0% starch, and 5.23–9.68% ash. Purification using α-amylase and β-xylanase in combination with pH adjustment and dialysis produced high purity β-glucan preparations (91–95%). The molecular weight (Mw) of β-glucan preparations from roller-milled fractions ranged from 117,600 to 852,400 g/mol. β-Glucan from flour had higher Mw than those from shorts and bran within the same cultivar, and β-glucan preparations from bran had the lowest Mw.

Content of Nutrients and Lignans in Roller Milled Fractions of Rye

Rye grain was roller milled into six flour fractions (607 g kg-1), a short (341 g kg-1) and a bran (52 g kg-1) in a B???hler laboratory mill. In the different flours (F1-F6) a progressive increase in ash (4-13 g kg-1), crude protein (39-87 g kg-1) and crude fat (5-17 g kg-1) concentration was found and a corresponding decrease in starch (853-699 g kg-1) concentration. Total dietary fibre (55-109 g kg-1) constituents and the lignans, matairesinol (0???05-0???22 mg kg-1) and secoisolariciresinol (0???21-0???38 mg kg-1), showed a different distribution with a maximal concentration in F5. The short and bran had higher concentrations of ash, crude protein, crude fat, dietary fibre components and lignans but a lower concentration of starch than the flours. Compared to the short, the bran contained more of all constituents analysed except mixed-linked beta-glucan and starch. A very high proportion of total dietary fibre components of the rye, such as arabinoxylan (72%), cellulose (76%) and Klason lignin (79%) as well as of matairesinol (87%) and secoisolariciresinol (73%), was found in the short and bran together. ??? 1997 SCI.