Rapeseed Protein Products Research Articles

Comparing Analytical Methods for Erucic Acid Determination in Rapeseed Protein Products.

Rapeseed meal and pressed cake are protein-rich by-products from rapeseed after oil extraction. Because of the high protein content, these by-products are an important source of food protein. Their use is motivated by the current pressure on protein prices, increasing demand for functional ingredients, and remaining controversy over wider use of soy. During process development for protein extraction from rapeseed cake or meal, special attention needs to be given to compounds such as erucic acid, which can cause problems if consumed in high amounts. Erucic acid determination is critical to ensure safety, since protein extraction procedures could lead to concentration of this compound in the final product. This research compared differences in extraction (Soxhlet and Folch) and derivatization techniques to obtain the highest erucic acid yield from rapeseed protein products. Results showed that no erucic acid accumulation occurred in the protein during its extraction from the rapeseed cake. The Soxhlet procedure was superior to Folch, as it yielded the highest concentrations of erucic acid. Furthermore, with the Folch procedure, some natural cis-configuration of erucic acid converted to its corresponding trans-configuration (brassidic acid). The latter is important, as ignoring this phenomenon can lead to underestimation of erucic acid content in rapeseed protein samples.

Effects of highly purified rapeseed protein isolate as fishmeal alternative on nutrient digestibility and growth performance in diets fed to rainbow trout ( Oncorhynchus mykiss )

The effective inclusion of rapeseed protein products as fishmeal alternatives in diets for carnivorous fish is still limited. Previous studies observed restrictions in both nutrient utilization and feed intake. Contents of nitrogen-free extracts (NfE) and anti-nutritive substances (ANFs) were made responsible for the latter mentioned limitations. Consequently, a highly purified rapeseed protein isolate with high protein content and low levels of both NfE and ANF was investigated in this study. In the first experiment, digestibility of the rapeseed protein isolate was determined. In the second experiment, the fishmeal portion (190 g kg-1) of a control diet was gradually replaced by rapeseed protein isolate to 33%, 66% and 100% of digestible protein and energy. Diets were fed twice per day to apparent satiation to triplicate groups of rainbow trout (Oncorhynchus mykiss). After 56 days of feeding, growth performance and health parameters were evaluated. Protein digestibility of the rapeseed protein isolate was 95.2%, and up to 66% of dietary fishmeal could be replaced without significantly affecting growth or health parameters. Total replacement of fishmeal led to significantly reduced feed intake and consequently reduced growth performance.

Fat encapsulation and supplementation with free amino acids cannot compensate for negative effects from dietary rapeseed protein isolate on growth performance of rainbow trout (Oncorhynchus mykiss)

There are still restrictions when using rapeseed protein products as fish meal alternatives in diets for rainbow trout. Digestibility of a particularly purified rapeseed protein isolate (protein content: 98.7 g 100g−1) was determined in rainbow trout (initial body weight: 178.2 ± 20.9 g) and it was used to exchange fish meal gradually (0 %, 66 % and 100 %) in diets based on commercial trout diets. To overcome potential limiting factors on growth performance from rapeseed protein isolates, duplicates of these experimental diets were encapsulated with stearic acid and one diet devoid of fish meal included rapeseed protein isolate as well as a mixture of free amino acids. The highest recorded crude protein digestibility (mean = 99.8 % ± standard deviation = 1.6 %) of rapeseed protein was reached using the stripping method. Daily feed intake (DFI) of the dietary group devoid of fish meal (DFI: 2.1 ± 0.06) was significantly reduced in comparison with control (DFI: 2.6 ± 0.07) at the end of the experiment. Similarly, feed conversion ratio (FCR) was significantly impaired when comparing control (FCR: 0.9 ± 0.01) to the dietary group with complete exchange of fish meal (FCR: 1.1 ± 0.02). Neither encapsulation of diets nor supplementation with free amino acids could overcome negative effects on growth performance from dietary rapeseed protein isolate inclusion. Results suggest that even highly purified rapeseed protein products can impair growth performance of rainbow trout and that factors other than ANFs could determine the effectiveness of rapeseed protein products as fish meal alternatives.

Effects of dietary rapeseed glucosinolates, sinapic acid and phytic acid on feed intake, growth performance and fish health in turbot (Psetta maxima L.)

Various antinutritional factors (ANF) present in rapeseed protein products can adversely affect the voluntary feed intake, growth performance and physiology as well as health of fish. The aim of the presented study was to evaluate which ANF is primarily responsible for the mentioned effects. Six identical semi-purified diets based on casein were produced. One unsupplemented basal diet (BD) served as control. The remaining five diets were supplemented with graded levels of glucosinolates (low = GL, high = GH), sinapic acid (low = SL, high = SH) and one level of phytic acid (PA). Diets were fed to triplicate groups of juvenile turbot (Psetta maxima L.) until apparent satiation for 50 days. Voluntary feed intake, growth performance as well as physiology of fish were investigated. Feed intake and growth performance of fish did not differ significantly (p < 0.05) between experimental groups. However, the feed conversion ratio (FCR) increased significantly due to dietary phytic acid supplementation (10 g kg−1feed). Also the protein efficiency ratio (PER) showed a strong tendency to decrease in fish fed diet PA (p = 0.0518). Furthermore no significant differences were detected among dietary treatments regarding the proximate final body composition, hepatosomatic index, splenic index and haematocrit of fish. Concentrations of the thyroidal hormones thyroxine (T4) and triiodothyronine (T3) in blood plasma were unaffected in all fish fed experimental diets. It was concluded that higher dietary levels of phytic acid, similar to commercial plant-based diets, can adversely affect nutrient utilisation in fish nutrition. Other investigated ANF did not harm fish performance significantly in applied concentrations when supplemented in a pure grade.

Physicochemical and functional properties of rapeseed protein isolate: influence of antinutrient removal with acidified organic solvents from rapeseed meal.

The presence of antinutritional constituents in rapeseed protein products (RPI), such as polyphenols, phytates, allyl isothiocyanates, and glucosinolates, is a formidable constraint. The effect of antinutrient removal from rapeseed meal with an organic solvent mixture (methanol/acetone, 1:1 v/v, combined with an acid (hydrochloric, acetic, perchloric, trichloroacetic, phosphoric)) on the physicochemical and functional properties of RPI was investigated. The extraction resulted in a substantial reduction of antinutrients from RPI, especially polyphenols and phytates, with concomitant decreases in protein yield and solubility. Treatment harbored significant improvement in the degree of whiteness, which was highest in the perchloric acid case. Surface hydrophobicity and free sulfhydryl group of RPI changed considerably, with perchloric acid-treated samples showing higher values, whereas the disulfide content remarkably increased in trichloroacetic acid- and phosphoric acid-treated samples, signifying aggregation. Intrinsic emission fluorescence and FTIR spectra showed significant changes in proteins' tertiary and secondary conformations, and the changes were more pronounced in samples treated with higher concentrations of acids. No appreciable alteration appeared among the electrophoretic profiles of proteins from pristine meal and those treated with lower levels of acids. Interfacial surface properties of proteins were variably improved by the solvent extraction, whereas the converse was true for their extent of denaturation. The results suggest that the physicochemical and conformational properties of RPI are closely related to its functional properties.

Effects of Antinutritional Factors on Protein Digestibility and Amino Acid Availability in Foods

Digestibility of protein in traditional diets from developing countries such as India, Guatemala, and Brazil is considerably lower compared to that of protein in typical North American diets (54-78 versus 88-94%). The presence of less digestible protein fractions, high levels of insoluble fiber, and high concentrations of antinutritional factors in the diets of developing countries, which are based on less refined cereals and grain legumes as major sources of protein, are responsible for poor digestibility of protein. The effects of the presence of some of the important antinutritional factors on protein and amino digestibilities of food and feed products are reviewed in this chapter. Food and feed products may contain a number of antinutritional factors that may adversely affect protein digestibility and amino acid availability. Antinutritional factors may occur naturally, such as glucosinolates in mustard and rapeseed protein products, trypsin inhibitors and hemagglutinins in legumes, tannins in legumes and cereals, phytates in cereals and oilseeds, and gossypol in cottonseed protein products. Antinutritional factors may also be formed during heat/alkaline processing of protein products, yielding Maillard compounds, oxidized forms of sulfur amino acids, D-amino acids, and lysinoalanine (LAL, an unnatural amino acid derivative). The presence of high levels of dietary trypsin inhibitors from soybeans, kidney beans, or other grain legumes can cause substantial reductions in protein and amino acid digestibilities (up to 50%) in rats and pigs. Similarly, the presence of high levels of tannins in cereals, such as sorghum, and grain legumes, such as fababean (Vicia faba L.), can result in significantly reduced protein and amino acid digestibilities (up to 23%) in rats, poultry, and pigs. Studies involving phytase supplementation of production rations for swine or poultry have provided indirect evidence that normally encountered levels of phytates in cereals and legumes can reduce protein and amino acid digestibilities by up to 10%. D-amino acids and LAL formed during alkaline/heat treatment of proteins such as casein, lactalbumin, soy protein isolate, or wheat proteins are poorly digestible (less than 40%), and their presence can reduce protein digestibility by up to 28% in rats and pigs. A comparison of the protein digestibility determination in young (5-week) versus old (20-month) rats suggests greater susceptibility to the adverse effects of antinutritional factors in old rats than in young rats. Therefore, the inclusion of protein digestibility data obtained with young rats, as the recommended animal model, in the calculation of PDCAAS (Protein Digestibility-Corrected Amino Acid Score) may overestimate protein digestibility and quality of products, especially those containing antinutritional factors, for the elderly. For products specifically intended for the elderly, protein digestibility should be determined using more mature rats.

LITERATURE ABSTRACTS

LITERATURE ABSTRACTS

Toxicological Evaluation of Rapeseed Protein Products by Means of a Thyroidea Stimulating Test

On the basis of a Thyroidea Stimulating Test (TSH-Test) with rats - rapeseed protein products from Brassica napus, Var. Solux (industrial rapeseed meal = REM; rapeseed protein isolate = RPI prepared from REM by extraction, ultra- and diafiltration; rapeseed extraction residue = RER, results after the protein extraction of REM) were tested with regard to their thyreotoxical efficacy. As expected the REM shows a strong thyreotoxic effect. In contrast to that and in comparison to a control diet the RER caused no negative effects on the thyroidea functions. The RPI-diet leads possibly to a slight impairment of metabolism of the thyroidea hormones. Toxikologische Bewertung von Rapssamen-Proteinprodukten mittels eines Schilddrusen-Stimulations-Tests Auf der Basis eines Schilddrusen-Stimulations-Tests (TSH-Test) mit Ratten sind drei Rapssamen-Proteinprodukte aus Brassica napus Var. Sollux (industrielles Raps-Extraktions-Schrot = RES; Rapssamen-Protein-Isolat = RPI, prapariert aus RES durch Extraktion sowie Ultra- u. Diafiltration der Extrakte; Extrakte; Extraktions-Ruckstand = RER, resultierend nach Proteinextraktion von RES) hinsichtlich ihrer moglichen thyreotoxischen Effekte untersucht worden. Wie zu erwarten war, zeigt das RES eine starke thyreotoxische Wirkung. Im Gegensatz dazu und im Vergleich zu einer Kontroll-Diat verursacht der RER keine negative Beeinflussung der Schilddrusen-Funktionen. Die RPI-Diat fuhrt moglicherweise zu einer geringen Beeintrachtigung des Stoffwechsels der Schilddrusenhormone.

Functional properties of rapeseed protein products with varying phytic acid contents

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFunctional properties of rapeseed protein products with varying phytic acid contentsDipak K. Dev and Kumar D. MukherjeeCite this: J. Agric. Food Chem. 1986, 34, 5, 775–780Publication Date (Print):September 1, 1986Publication History Published online1 May 2002Published inissue 1 September 1986https://doi.org/10.1021/jf00071a002RIGHTS & PERMISSIONSArticle Views365Altmetric-Citations31LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (830 KB) Get e-Alerts Get e-Alerts

Valorisation Nutritionnelle des Protéines de Colza par un Traitement Hydro-Thermique des Graines

In view of extending the utilization and versatility of rapeseed proteins in human food, a comparison was made for two different varieties “OO” and “Jet Neuf” from the viewpoint of the effects of processing conditions for the preparation of nontoxic rapeseed protein products on the extraction yields of nitrogen and lipid, chemical, physicochemical and nutritional properties of the processed products. We have developed a process which requires no-complex equipment and solids, protein and oil losses are small, the costs and the feasibility for industrial use and commercial application have been taken into account. We obtained two different fractions by a simple centrifugation, the high protein fraction (FRP) can adapt to human consumption and high fiber fraction (FRT) for animal feeds.The extraction process was carried out with whole seeds and de-hulled seeds. The developed procedure could be adapted to other oilseeds for preparing protein products. The obtained products have a very low level of antinutritional factors, i.e. glucosinolates and polyphenols. FRP contains 53% protein and 18% fibers with a PER value (2.60) superior to casein; FRT contains 35% proteins and 46% fibers with a PER value of 2.26 slightly inferior to that of FRP.

Rapeseed protein products.

AbstractDuring recent years somewhat different methods of producing rapeseed protein concentrates (RPC) and isolates (RPI) have been developed. Texturizing of RPC has also been studied. Functional properties of RPC such as solubility, water‐and fat‐binding, emulsifying and foaming have been studied together with their organoleptic properties. Very bland RPC can be produced. How variables obtained in the instrumental analysis are related to those obtained in the sensory analysis has also been studied. Rapeseed flours are comparable to soy flours in water absorption and give higher fat absorption. Oil emulsification and whippability values depend on processing. Rapeseed protein concentrates, and isolates show excellent water‐ and fat‐holding capacity. The isolate is high in oil emulsification and whipping characteristics. Rapeseed protein products can therefore be used as extenders or binders in meat patties or sausages. Their use in bread and other food items also has been studied. Due to high contents of lysine, methionine and cysteine, rapeseed proteins have a higher nutritive value than any other known vegetable protein. Their nutritive value is as high as that of good animal proteins. This has been shown in growth studies on rats and in a nitrogen balance study on studient volunteers. The safety of RPC has been tested through many years. With the exception of a negative effect on the zinc balance in rats, which can be compensated, no negative finding has been recorded.

Chemical constituents and protein food processing of rapeseed.

AbstractIn rapeseed, as in other oilseeds, there are some substances that adversely affect nutritional value. By application of appropriate technological processes, the antinutritive factors are removed and the final protein products appear to have high nutritive value. Compared with the soybean, rapeseed presents some unique problems. When processing rapeseed into protein foods, it is necessary to take into account high losses of nitrogen substances (nonprotein nitrogen), and higher costs of removing glucosinolates and their derivates, as well as phenolic compounds. Technically and economically feasible methods of reducing cellulose and phytate contents should be developed. In view of the presence of many constituents which lower the nutritional value of rapeseed protein products, it would appear that rapeseed is presently not a suitable raw material for production of food grade protein flour and grits. On the contrary, rapeseed protein concentrates and their texturates have satisfactory nutritional quality and feature good functional properties. Rapeseed isolates, except for poorer spinning properties, have similar characteristics to those of soybean isolates, but, as a result of low protein yields, their production is uneconomical. Recent progress in the breeding of glucosinolate‐free and low fiber rapeseed varieties offers a new approach for development of processing methods for useful protein products based on this raw material.

Detoxification of Rapeseed Protein Products by an Activated Carbon Treatment

Rapeseed protein, extracted at pH 10 from rapeseed meal (Brassica campestris var. Span) and isoelectrically precipitated, contained 0.75mg 3-butenyl isothiocyanate, 0.57mg 4-pentenyl isothiocyanate and 0.51mg 5-vinyl-2-oxazolidinethione (goitrin) per g solids after myrosinase treatment.A two-stage process was developed to decrease the levels of these toxins. A suspension of isoelectrically precipitated protein was incubated at pH 7.2 with crude myrosinase and passed through a granular activated carbon column at pH 10. 4-Pentenyl isothiocyanate decreased to 0.006mg/g and only traces of other toxins were detected, 99.96% elimination of aglycones of glucosinolates present in the original meal. Carbon treatment alone in the pH range from 3 to 10 removed over 93% (maximum 98% of pH 3) of isothiocyanates. The detoxification efficiency decreased at pH above 10. The carbon treatment was also partially effective in nitrile removal. It was found that ground white mustard could replace crude myrosinase for hydrolysis of glucosinolates.A 24-hour storage of aglycone-containing protein solutions caused increased losses of isothiocyanates by increasing pH from 5 to 10, probably due to pH-dependent isothiocyanate-protein interaction.Although the carbon treatment almost completely removed purifieid glucosinolates from their aqueous solutions when unhydrolyzed, the results were not reproducible with solutions containing rapeseed protein.

Some Functional Properties of Rapeseed Protein Isolates and Concentrates

Protein isolates and concentrates obtained from rapeseed flour by a successive water, HCl, and NaOH extraction process were subjected to baking, emulsification, and whipping tests.In baking, a 5% replacement of wheat flour with rapeseed protein isolates and concentrates decreased loaf volume by 10 to 15% and 20%, respectively. Addition of .5% emulsifier (Atmul 124) restored loaf volume to most breads: 10 to 15% larger loaf volume for the water and HCl extracted isolate breads than the all-wheat control; 8% inferior loaf volume for the protein concentrate breads except for the NaOH extracted concentrate (12% larger loaf volume).Whipping tests with 3% replacement of egg white protein by isolates or concentrates generally resulted in a decreased specific volume compared to the all-egg white control. An exception was the HCl extracted isolate with a 10% larger specific volume than the control. All fractions improved foam stability; particularly, meringues containing the water extracted isolate showed no sign of drip for 1.5 h.The water extracts displayed highest emulsification capacity; 45ml of corn oil per 100mg of protein in the isolate compared to approximately 35ml for other fractions. Emulsions containing the HCl extract showed remarkable stability: 200 min compared to 3 min for the control.No significant correlation was observed between the solubility of rapeseed protein products and their functional properties.