Rapeseed protein isolates by countercurrent extraction and isoelectric precipitation

1977 ◽  
Vol 25 (1) ◽  
pp. 193-197 ◽  
Author(s):  
Ahmad S. El Nockrashy ◽  
Kumar D. Mukherjee ◽  
Helmut K. Mangold
Keyword(s):  
Countercurrent Extraction ◽  
Isoelectric Precipitation ◽  
Protein Isolates ◽  
Rapeseed Protein

Countercurrent extraction-isoelectric precipitation of sunflower seed protein isolates

1981 ◽  
Vol 32 (2) ◽  
pp. 166-174 ◽  
Author(s):  
Fakhriya S. Taha ◽  
Mehassen Abbasy ◽  
Ahmed S. El-Nockrashy ◽  
Zein E. Shoeb
Keyword(s):  
Sunflower Seed ◽  
Seed Protein ◽  
Countercurrent Extraction ◽  
Isoelectric Precipitation ◽  
Protein Isolates

scholarly journals Enhanced Solubility of Rapeseed Meal Protein Isolates Prepared by Sequential Isoelectric Precipitation

Foods ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 703
Author(s):  
Hristo Kalaydzhiev ◽  
Radoslav Georgiev ◽  
Petya Ivanova ◽  
Magdalena Stoyanova ◽  
Cristina L. M. Silva ◽  
...  
Keyword(s):  
Protein Solubility ◽  
Rapeseed Meal ◽  
Protein Isolate ◽  
Protein Fractions ◽  
Isoelectric Precipitation ◽  
Protein Isolates ◽  
Sds Page ◽  
Enhanced Solubility ◽  
Meal Protein ◽  
Biochemical Analyses

The solubility of plant protein isolates is a key determinant of their potential application. Two protein isolates (PI) from ethanol-treated industrial rapeseed meal, PI10.5–2.5 and PI2.5–8.5, were prepared by sequential isoelectric precipitation of alkali-extracted proteins (pH 12) starting from pH 10.5 to 2.5 or from pH 2.5 to 8.5, respectively. Biochemical analyses revealed that PI2.5–8.5 contained a higher amount of crude protein (72.84%) than PI10.5–2.5 (68.67%). In the same protein isolate, the level of total phenols (0.71%) was almost two-fold higher than that in PI10.5–2.5 (0.42%). No glucosinolates were established in both protein isolates. SDS-PAGE analysis demonstrated that PI10.5–2.5 contained 10 to 15 kDa protein fractions in a relatively higher amount, while PI2.5–8.5 was enriched in 18 to 29 kDa protein fractions. PI10.5–2.5 exhibited high solubility, varying from 41.74% at pH 4.5 to 65.13% at pH 6.5, while PI2.5–8.5 was almost two-fold less soluble under the same conditions. Up to pH 5.5, the addition of NaCl at 0.03 and 0.25 M diminished the solubility of PI2.5–8.5, while the solubility of PI10.5–2.5 was increased. The supplementation of PI10.5–2.5 with 0.25 M NaCl enhanced the protein solubility to 56.11% at pH 4.5 and 94.26% at pH 6.5. The addition of 0.03 M NaCl also increased the solubility of this protein isolate but to a lower extent. Overall, the approach for sequential precipitation of proteins influenced the biochemical characteristics, protein fractional profile and solubility of prepared protein isolates.

Physicochemical and Functional Characterisation of Amaranth (Amaranthus hypochondriacus) Protein Isolates Obtained by Isoelectric Precipitation and Micellisation

2005 ◽  
Vol 11 (4) ◽  
pp. 269-280 ◽  
Author(s):  
M. Y. Cordero-de-los-Santos ◽  
J. A. Osuna-Castro ◽  
A. Borodanenko ◽  
O. Paredes-López
Keyword(s):  
Protein Denaturation ◽  
Gel Filtration ◽  
Isoelectric Precipitation ◽  
Scanning Calorimetry ◽  
Protein Isolates ◽  
Amaranthus Hypochondriacus ◽  
Molecular Weights ◽  
Functional Characterisation ◽  
Definition Of ◽  
Two Peaks

Amaranth protein isolates were obtained by two distinct methods, i.e. alkaline extraction-isoelectric precipitation (IP) and micellisation (MP). IP had a greater protein yield (56.4%) and protein content (93.1%) than MP (15.9 and 80.2%, respectively). The gel filtration chromatogram of IP isolates displayed a single peak of ca. 1,380 kDa, whereas MP isolates showed two peaks at 905kDa and 190kDa. A commercial soybean isolate (CSI), analysed for comparison purposes, presented two peaks with molecular weights of 340kDa and 62kDa. Differential scanning calorimetry showed that amaranth isolates were characterised by two endothermic events, predominating in both isolates the second endotherm with a denaturation temperature of 98.7 °C for IP and 97.2 °C for MP. The better definition of MP endotherms and their higher denaturation enthalpy suggested a more homogenous and less denatured protein population, in comparison to IP and CSI. The amaranth isolates had better solubility at alkaline pHs than the CSI. Foaming and emulsification were better at acidic pH for both IP and MP. Colorimetric evaluations showed that the two amaranth isolates had a higher whiteness index than the CSI. In conclusion, extreme pH treatments in IP resulted in a partial protein denaturation and milder treatments in MP resulted in less protein denaturation and improvement of some functional properties.

Kaempferol 3-O-(2‴-O-Sinapoyl-β-sophoroside) Causes the Undesired Bitter Taste of Canola/Rapeseed Protein Isolates

2018 ◽  
Vol 67 (1) ◽  
pp. 372-378 ◽  
Author(s):  
Christoph Hald ◽  
Corinna Dawid ◽  
Ralf Tressel ◽  
Thomas Hofmann
Keyword(s):  
Bitter Taste ◽  
Protein Isolates ◽  
Rapeseed Protein

scholarly journals Postprandial Metabolic Response to Rapeseed Protein in Healthy Subjects

Nutrients ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2270
Author(s):  
Christin Volk ◽  
Corinna Brandsch ◽  
Ulf Schlegelmilch ◽  
Monika Wensch-Dorendorf ◽  
Frank Hirche ◽  
...  
Keyword(s):  
Soy Protein ◽  
Healthy Subjects ◽  
Metabolic Response ◽  
Insulin Response ◽  
Protein Isolate ◽  
Favorable Effect ◽  
Plant Proteins ◽  
Protein Isolates ◽  
Rapeseed Protein ◽  
Postprandial Insulin

Plant proteins have become increasingly important for ecological reasons. Rapeseed is a novel source of plant proteins with high biological value, but its metabolic impact in humans is largely unknown. A randomized, controlled intervention study including 20 healthy subjects was conducted in a crossover design. All participants received a test meal without additional protein or with 28 g of rapeseed protein isolate or soy protein isolate (control). Venous blood samples were collected over a 360-min period to analyze metabolites; satiety was assessed using a visual analog scale. Postprandial levels of lipids, urea, and amino acids increased following the intake of both protein isolates. The postprandial insulin response was lower after consumption of the rapeseed protein than after intake of the soy protein (p < 0.05), whereas the postmeal responses of glucose, lipids, interleukin-6, minerals, and urea were comparable between the two protein isolates. Interestingly, the rapeseed protein exerted stronger effects on postprandial satiety than the soy protein (p < 0.05). The postmeal metabolism following rapeseed protein intake is comparable with that of soy protein. The favorable effect of rapeseed protein on postprandial insulin and satiety makes it a valuable plant protein for human nutrition.

scholarly journals Changes in Total Phenolic and Protein Contents during Production of Protein Isolates from Carica papaya (Pawpaw) Seeds

2016 ◽  
Vol 4 (11) ◽  
pp. 1006 ◽  
Author(s):  
Oseni Kadiri ◽  
Saka O Gbadamosi ◽  
Babatunde Olawoye ◽  
Charles T Akanbi
Keyword(s):  
Protein Content ◽  
Total Phenolic Content ◽  
Carica Papaya ◽  
Phenolic Content ◽  
Production Method ◽  
Protein Isolate ◽  
Total Phenolic ◽  
Isoelectric Precipitation ◽  
Protein Isolates ◽  
Gallic Acid Equivalent

The effect of different processing stages- defatting, solubilization, isoelectric precipitation, neutralisation and lyophilisation on the total phenolic content and protein content of Carica papaya (pawpaw) seeds (CPS) full-fat flour (CFF), defatted flour (CDF), protein concentrates (CPC) and protein isolates (CPI) was studied. The folin-ciocalteu procedure was used to assess the total phenolic concentrations of the Carica papaya products and results were expressed as gallic acid equivalent (GAE). Optimal protein content was estimated at pH 10 for all samples. Higher levels of polyphenols were extracted using water-methanol (20/80) mixture compared to 100% methanol. Total phenolic content (TPC) was demonstrated in a trend of CDF > CPC > CFF > CPI with CDF having the highest TPC. The finding suggested a more economical protein isolate production method. The study concludes that the processing of CPS into the various products (CFF, CDF, CPC & CPI) improves its protein and polyphenol content.

scholarly journals Development of optimal method of obtaining pea isolated proteins for use in breeding for quality

2020 ◽  
Vol 21 (4) ◽  
pp. 408-416
Author(s):  
S. V. Bobkov ◽  
O. V. Uvarova
Keyword(s):  
Crude Protein ◽  
Protein Extraction ◽  
Protein Isolate ◽  
Isoelectric Precipitation ◽  
Optimal Method ◽  
Protein Isolates ◽  
Second Stage ◽  
Pea Proteins ◽  
Two Stages

The article provides the results of the experiments on determination of optimal parameters for obtaining isolated proteins from grains of cultivated and wild pea for use in breeding for quality. The flour of pea varieties Sophia, Rodnik and wild accession k-3370 (Pisum sativum L. ssp. Elatius) were used in the experiment. Isolated pea proteins were obtained based on alkaline extraction and isoelectric precipitation. The experiments were carried out with the use of complete and fractional factorial plans with two levels of factors. Extraction and precipitation of protein were conducted in two stages. One hundred grams of flour were used for extraction. Influence of factors (variety, pH, duration of extraction) on the yield of isolated protein, extraction efficiency, crude protein and fat content in protein isolates was studied. All isolates were characterized by high content of crude protein (90.2-93.1 %). It was determined that increase of pH higher than eight led to enhancement of protein yield and decrease of crude protein content. The results obtained raise the possibility of effective extraction at decreased level of pH that prevents the formation of toxic chemicals. Increase of pH promoted fat accumulation in protein isolate especially at the second stage of extraction. Thus, obtaining protein isolates for evaluation of pea genetic resources should be conducted during a single cycle of extraction and precipitation. The experiments have not revealed significant differences between cultivated and wild pea as to the technology of extraction. The results of the studies are important for evaluation of pea genetic resources according to functional properties of protein isolates.

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