Rapeseed Hulls Research Articles

The Possibility of Using Waste from Dye Sorption for Methane Production

The aim of this study was to determine the effect of sorption of Basic Red 46 (BR46) dye by lignocellulosic biomass on the susceptibility of the sorbed waste to anaerobic decomposition by anaerobic digestion. The research material used in the experiment consisted of two types of biomass: stalks with leaves and inflorescences after mowing Canadian goldenrod (Solidago canadensis L.) (GB), and rapeseed hulls (RHs) after oil pressing. During the anaerobic decomposition of RHs, 732.30 NmL/gVS and 646.63 NmL/gVS of methane were obtained from the non-sorbed substrate and the plant material after dye sorption, respectively. Similarly, in the variants using Canadian goldenrod, the production was 220.70 NmL/gVS and 183.20 NmL/gVS. The GB sorbent sorbed 34% more BR46 dye than the RH sorbent, which is likely to have resulted in the accumulation of VFA and contributed to the partial inhibition of methane production. In light of the obtained results and the literature data, it is concluded that there is a possibility of effective use of dye sorption waste for methane production.

Characterisation and quantification of condensed tannins in rapeseed hulls and meals by depolymerization methods

Condensed tannins (i.e. polymerized procyanidins) were quantified in crude samples of rapeseed meal and hulls using two acidolysis methods. When it was applied directly on crude material, the colorimetric butanol-HCl assay allowed an estimation of two grams of tannins per kilogram of dried hulls. Interestingly, the estimation was more than double after solvent extraction using sodium dodecyl sulphate (SDS) when the colorimetric method was applied on both the extract and the insoluble residue. By altering the plant tissues organization, SDS treatment may allow a better accessibility of the depolymerizing reagents. However, this colorimetric assay was judged approximate because of browning side-reaction likely involving other components. Phloroglucinolysis combined with HPLC-UV-MS analysis was more rigorous and informative confirming that rapeseed hulls condensed tannins were essentially constituted of epicatechin units with an average degree of polymerization of close to 11. According to this method, the concentration of condensed tannins in hulls was estimated to 5.19 g/kg in the optimized conditions established through a factorial experimental design allowing optimization of hydrochloric acid concentration, reaction duration and temperature.

A new method for rapeseed hulls purification – Proof of concept

The loss of fats in the hulls is one of the main obstacles limiting the industrial implementation of rapeseed dehulling. The main reason resides in the shape of rapeseed outer cotyledons which resemble to the hulls’ shape and make it difficult to separate. The purpose of this study is to propose a new method for the purification of rapeseed hulls. After primary separation by aspiration, the mixture of hulls and kernels is passed between a pair of flat rolls where kernels are flattened and stick to the metal while the hulls do not. We exploited this property to adapt a small laboratory flaker with two counter-rotating cylinders of 65 mm diameter with scrapers that make the kernels fall away from the hulls. Process optimization by tunning experimental conditions (hulls moisture content, roller spacing, roller speed and feed rate) allowed the determination of the optimal operating conditions. Experiments showed that wetting improves the purity of the hulls but reduces the one of the recovered kernels. A gap of 0.1 mm was necessary. In addition, it was shown that the sorting quality depends on the ratio flow-rate / rotation-speed. The best performances are reached around 1 g.s−1.rpm−1. In these conditions, the hulls and kernels purity were 96% and 94% respectively. This preliminary work has allowed us to prove the concept. The next step will be to develop a pilot plant to validate the process efficiency on a larger scale (100 kg/h).

Kinetic Analysis and Reaction Mechanism of Hydrothermal Hydrolysis of Rapeseed Hulls to Produce Polyphenols

Kinetic Analysis and Reaction Mechanism of Hydrothermal Hydrolysis of Rapeseed Hulls to Produce Polyphenols

Phytase supplementation in diets rich in fiber from rapeseed enhances phosphorus and calcium digestibility but not retention in broiler chickens

Two experiments were conducted on broilers to assess the effect of dietary fiber from 00-rapeseed meal (RSM) on phosphorus (P) and calcium (Ca) apparent ileal digestibility (AID) and retention (AR) during the growing (Exp1: 10 to 21 d) or finishing period (Exp2: 21 to 31 d) in diets supplemented or not with microbial phytase. Each experiment involved 144 male Cobb 500 fed one of 8 diets. Fiber content was modulated by incorporating whole RSM, RSM from dehulled rapeseeds, either raw or supplemented with 2 levels of defatted rapeseed hulls. Diets were supplemented or not with 750 phytase units of microbial phytase per kg. Excreta were collected from d 14 to d 17 (Exp1) and from d 27 to d 30 (Exp2) to measure AR. At the end of experiments, digestive tracts were sampled and weighed. The distal ileum and tibias were collected to measure AID and bone mineralization, respectively. Age did not significantly alter the response of birds to the addition of dietary fiber. Inclusion of hulls decreased growth performance (P < 0.05). The weight of the proventriculus-gizzard (PG) increased with the dietary fiber content in Exp1: The decreased weight observed using dehulled RSM was reversed following the inclusion of hulls. In both trials, while the presence of phytase increased the AID of P (P < 0.001) but not Ca, the inclusion of hulls with phytase improved the AID of P and Ca [linear (Lin), P < 0.05]. This effect could depend on the effect of fiber on PG development and physiology. Hulls decreased the moisture content of excreta (P < 0.01), suggesting higher water retention or lower water consumption with fiber. The AR of P was lower than AID of P with hulls, contrary to Ca, suggesting a metabolic imbalance. The decrease of AR together with the decrease of bone characteristics indicates a lack of Ca in diets with hulls and suggests that P and Ca provision should be adapted to the level and the origin of fiber inclusion.

Effects of rapeseed meal fiber content on phosphorus and calcium digestibility in growing pigs fed diets without or with microbial phytase

The optimization of dietary phosphorus (P) and calcium (Ca) supply requires a better understanding of the effect of dietary fiber content of co-products on the digestive utilization of minerals. This study was designed to evaluate the effects of dietary fiber content from 00-rapeseed meal (RSM) on P and Ca digestibility throughout the gastrointestinal tract in growing pigs fed diets without or with microbial phytase. In total, 48 castrated male pigs (initial BW=36.1±0.4 kg) were housed in metabolic crates for 29 days. After an 8-day adaptation period, pigs were allocated to one of the eight treatments. The impact of dietary fiber was modulated by adding whole RSM (wRSM), dehulled RSM (dRSM) or dRSM supplemented with 4.5% or 9.0% rapeseed hulls (dRSMh1 and dRSMh2). Diets contained 0 or 500 phytase unit of microbial phytase per kg. From day 14 to day 23, feces and urine were collected separately to determine apparent total tract digestibility (ATTD) and apparent retention (AR) of P and Ca. At the end of the experiment, femurs and digestive contents were sampled. No effect of variables of interest was observed on growth performance. Microbial phytase increased ATTD and AR of P (P<0.001) but the P equivalency with the wRSM diet was lower than expected. Moreover, stomach inorganic P (iP) solubility was improved by microbial phytase (P<0.001). The ATTD of Ca was not affected by microbial phytase which increased AR of Ca and femur characteristics (P<0.05). Ileal recovery of P was not affected by microbial phytase but cecal recovery was considerably reduced by microbial phytase (P<0.001). The decrease in digesta pH between the distal ileum and cecum (7.6 v. 5.9) enhanced the solubility of iP and may have improved its absorption, as supported by the negative relationship between soluble iP and pH (R2=0.40, P<0.001 without microbial phytase and R2=0.24, P=0.026 with microbial phytase). The inclusion of hulls improved the solubility of iP (P<0.05). In conclusion, dehulling does not largely increase nutrient digestibility although dRSM seems to improve the efficacy of microbial phytase in releasing phosphate in the stomach. Moreover, dietary fiber may affect solubilization process in the cecum which potentiates the effect of microbial phytase on P digestibility.

Chemical Characterization of Non-Saccharidic and Saccharidic Components of Rapeseed Hulls and Sunflower Shells

The main compositional characteristics of rapeseed hulls (RH) and sunflower shells (SS) were examined in terms of non-cellulosic components. The non-sugar fractions were analyzed by solid nuclear magnetic resonance (NMR) and pyrolysis-gas-chromatography/mass spectrometry (Pyr-GC-MS). Unlike SS, RH is a non-lignified biomass. The presence of large amounts of catechol and cresol suggested the presence of phytomelanin in both materials. Sugars accounted for 60% of RH and 45% of SS. Pectic compounds were extracted from the holocellulose of RH with ammonium oxalate or with citric acid, with 17% and 31% yield, respectively. A glucuronoxylan was isolated from the holocellulose of SS in basic conditions with 16% yield.

Solute and gas assisted mechanical expression for green oil recovery from rapeseed hulls

This work aims at evaluating the alternative technologies of solvent (liquid) and gas assisted mechanical expression to recover oil from rapeseed hulls and comparing these technologies with conventional solute extraction (SE). First, SE and solute assisted mechanical expression (SAME) have been applied using hexane and green solvents (water, ethanol, water/ethanol mixture) to extract efficiently oil and other bioactive compounds (polyphenols, and proteins). In order to avoid the use of organic solvents, oil extraction yield was compared to that of gas assisted mechanical expression (GAME) technology after optimizing the extraction parameters (effective pressure, CO2 flow, and the impact of pre-treatments (grinding and/or cooking)). Results show that the highest extraction yield (65%) with GAME was obtained using 35MPa effective pressure, 8.5kg/h CO2 flow, and without pre-treatment. Although similar extraction yields have been recorded between the three extraction processes, the use of GAME technology allowed the recovery of oil without subsequent purification steps (removing the extraction solvent, meal desolvation), and without pre-treatment.

Innovative physically-assisted soda fractionation of rapeseed hulls for better recovery of biopolymers

A better knowledge of the effect of non-conventional pretreatment technologies, which can avoid the use of high temperatures and detrimental solvents, is necessary.

Profile and distribution of soluble and insoluble phenolics in Chinese rapeseed (Brassica napus)

The profile and distribution of soluble and insoluble phenolics in 10 rapeseed (Brassica napus) varieties were studied in this work. Photometric results show that the soluble total phenolic content (TPC) and the total tannin content (TTC) of rapeseed dehulled flours are much higher than those of rapeseed hulls. Soluble and insoluble phenolics were further analysed by HPLC/MS and MS/MS. For soluble phenolics, seven species were identified and quantified. Sinapine was found to be the major component in both defatted rapeseed hulls and dehulled flours, with its content ranging from 0.93 to 1.76mg/g and 15.65 to 21.88mg/g, respectively. For insoluble phenolics, eight phenolic acids were detected in rapeseed hulls, while only two of them were found in their dehulled flours. Sinapic acid and protocatechuic acid, which also were found in dehulled flours, were identified as two major insoluble phenolics in rapeseed hulls. Insoluble TPCs in defatted rapeseed hulls and dehulled flours were shown to be in the similar range.

Protein‐precipitating capacity of crude condensed tannins of canola and rapeseed hulls

AbstractThe protein‐precipitating potentials (PPP) of soluble condensed tannins (SCT) were determined in hulls from several samples of canola and rapeseed varieties. The PPP were expressed as slopes of lines (titration curves) reflecting the amount of SCT‐protein precipitated vs. the amount of SCT added to the reaction mixture. The slopes (Sp) of titration curves obtained using the protein‐precipitation assay ranged from 2.96 to 10.91 (absorbance units at 510 nm per mg SCT), and those of titration curves, obtained using the dye‐labeled bovine serum albumin (BSA) assay (Sd), ranged from 28.1 to 267 (% precipitated BSA per mg SCT). For both assays, a statistically significant (P≤0.001) semilogarithmic linear correlation existed between the slopes and the SCT contents in the canola and rapeseed hulls. Higher amounts of SCT‐protein complexes were precipitated at 40°C than at room temperature. Determination of titration curves under standardized conditions (type and concentration of protein, pH and temperature) afforded meaningful differences in the slopes among the range of SCT extracts from canola and rapeseed hulls used in this study.

Multivariate model for the prediction of soluble condensed tannins in crude extracts of polyphenols from canola and rapeseed hulls

AbstractThe feasibility of using ultraviolet spectrophotometry to develop multivariate models for prediction of soluble condensed tannins (SCT) content in crude polyphenols extracts from canola and rapeseed hulls was investigated. The polyphenols were extracted from hulls using 70% (vol/vol) aqueous acetone. Partial least squares regression was used to correlate the spectral data of the crude polyphenols in methanol between 265–295 nm with the SCT content in hulls. Both the proanthocyanidin (P) and the vanillin (V) assays were used to provide reference data for creating the models. The predictive ability of the models is good, as indicated by the RPD values [the ratio of the standard deviation of data to the standard error of calibration (SEC) of above 5. Additionally, the SEC values suggest that P is superior to V in predicting the SCT content of hulls using this method.

Antioxidant activity of crude tannins of canola and rapeseed hulls

AbstractThe antioxidant activity of crude tannins of canola and rapeseed hulls was evaluated by β‐carotene‐linoleate, α,α‐diphenyl‐β‐picrylhydrazyl (DPPH) radical, and reducing power assays. Crude tannins were extracted from three samples of Cyclone canola (high‐tannin) hulls and Kolner, Ligaret, and Leo Polish rapeseed (low‐tannin) hulls with 70% (vol/vol) acetone. The total phenolic content in crude tannin extracts ranged between 128 and 296 mg of sinapic acid equivalents per 1 g of extract. The ultraviolet spectra of methanolic solution of canola extracts showed two absorption maxima (282 and 309 nm), whereas those of rapeseed extracts exhibited a single maximum (326 nm). Crude tannins isolated from canola hulls exerted significantly (P&lt;0.025) greater antioxidant activity than those from rapeseed in all three assays. The scavenging effect of all crude tannins, at a dose of 1 mg, on the DPPH radical ranged from 35.2 to 50.5%. The reducing power of Cyclone canola hull extracts on potassium ferricyanide was significantly (P≤0.0025) greater than that of rapeseed hull extracts, and the observed data correlated well (r=0.966; P=0.002) with the total content of phenolics present.

Apparent protein digestibility and recovery of endogenous nitrogen at the terminal ileum of pigs fed diets containing various soyabean products, peas or rapeseed hulls

Effects of the use of three different soyabean products (soya concentrate and two different soyabean meals), peas or rapeseed hulls in the diet on the apparent ileal digestibility of CP (N × 6.25) and recovery of ileal endogenous nitrogen (N) in weanling pigs were investigated. Ileal endogenous N was measured using the 15N-isotope dilution method. Thirteen castrated male pigs (BW of 12–23 kg) were fed maize starch-based diets containing either soya concentrate (SC), purified rapeseed hulls (pRH) and SC (SRH diet), soyabean meal (SBM), a mixture of toasted and untoasted soyabean meal (mSBM) or peas. The apparent ileal digestibility (AID) of dry matter (DM) for the SC, SRH, SBM, mSBM and pea diets was 82.1, 74.3, 83.3, 80.0 and 74.9% ( P < 0.05), respectively. The AID of CP for these diets was 82.4, 67.6, 81.6, 68.0 and 76.9% ( P < 0.05), respectively. Similar differences in the AID for amino acids (AA) in the diets were found. The AID for CP and for the sum of AA in the pRH, as calculated by the difference between the SC and SRH diet, were 26 and 41%, respectively. For the SC, SRH, SBM, mSBM and pea diet, ileal recovery (g/kg of DM intake) for endogenous N were 2.79, 3.46, 2.73, 4.89 and 3.29 ( P < 0.05), respectively, and for dietary N 1.16, 4.11, 1.64, 4.15 and 2.53 ( P < 0.05), respectively. For the SC, SBM and mSBM diets, differences in AID of CP and AA were associated with differences in both the ileal recovery of endogenous N and the recovery of undigested dietary N. Differences in trypsin inhibitor activity (TIA) of the soya products were likely associated with these observations. It was also concluded that fibre (Neutral Detergent Fibre; NDF) in pea could be at least in part responsible for the relatively low AID of CP and AA and the high recovery of ileal endogenous N in the pea diet. The low AID of CP and AA of pRH was likely related to the association of protein to the fibre matrix in the fibre-rich rapeseed hulls.

COMPARISON OF THE EFFECTS OF DARK AND YELLOW RAPESEED HULLS, SOYBEAN HULLS AND A PURIFIED FIBER SOURCE ON GROWTH, FEED CONSUMPTION AND DIGESTIBILITY OF DIETARY COMPONENTS IN STARTER PIGS

A trial involving a total of 56 weanling pigs was conducted to investigate the effects of including dark (Tower) and yellow (R500) rapeseed hulls, soybean hulls and a purified fiber source (Celufil) as 10% of the diets of starter pigs. The animals were offered the experimental diets from 5 to 9 wk of age. The pigs fed on the R500 hull diet had lower (P &lt; 0.05) average weight gain (273 g/day) and feed consumption (481 g/day) values than those fed the other diets, which ranged from 400 to 466 g/day and from 755 to 882 g/day, respectively. The feed efficiency (gain:feed) values were similar for all dietary treatments with values ranging from 0.53 to 0.57. The lower feed consumption observed for the R500 hull diet was suspected to be due to poor palatability of these hulls probably caused by some hydrolytic products of glucosinolates. The dry matter, energy and protein digestibility coefficients for both rapeseed hull diets were similar. The R500 rapeseed hull diet had higher (P &lt; 0.05) digestibility values for dry matter, energy and protein than the soybean hull diet while the Tower rapeseed and soybean hull diets had similar digestibility values for these components. The Celufil diet had similar dry matter and energy digestibility values with the SBH diet but the protein digestibility value for Celufil was higher (P &lt; 0.05) than that of the soybean hull diet and similar to those of the rapeseed hull diets. The crude fiber digestibility values were similar for all diets. Key words: Dark and yellow rapeseed, hulls, fiber, growth performance, digestibility, swine

Dark and Yellow Rapeseed Hulls, Soybean Hulls and a Purified Fiber Source: Their Effects on Dry Matter, Energy, Protein and Amino Acid Digestibilities in Cannulated Pigs

Summary Hulls from Tower rapeseed (dark colored cultivar), R500 rapeseed (yellow colored cultivar) and soybean were included in semipurified diets for growing pigs at 10%, to investigate the effects of these fiber sources on dry matter, energy and protein digestibilities. Celufil, a purified fiber source, was also included in another diet at a 10% level for comparison. Casein, which was the main protein source, was added at a 15% level in all the diets. Four 40-kg barrows fitted with cannulas at the terminal ileum were used in a digestibility trial with a 4  4 Latin square design. The digestibilities of dry matter, protein and amino acids were measured to the ends of both the small and large intestines, while the digestibility of energy was measured only over the entire gastrointestinal tract. The true protein digestibility was also determined at the ileal and fecal levels. The Celufil diet had a higher cellulose content (8.7%) than the other diets (2.8 to 5%). The

Ruminal degradation and in vivo digestibility of processed rapeseed meal

The digestibility and nutritive value of rapeseed meal processed in different ways were studied with adult rams fed on alkali-treated straw. The rumen degradability was determined by the nylon bag technique. The rapeseed meal feeds were: 1) untreated rapeseed meal, 2) heat-treated rapeseed meal (2—5 sec. at over 100°C), 3) heat-treated rapeseed meal + 5 % urea phosphate and 4) heat-treated rapeseed meal + 10 % rapeseed hulls. The heat treatment reduced the rumen degradation and in vivo digestibility of the rapeseed meal, although not significantly (P &gt; 0.05). Addition of urea phosphate to the heat-treated rapeseed meal increased the ruminal degradability of the crude protein and improved the digestibility of all the constituents of the rapeseed meal, especially that of crude fibre (P &gt; 0.05). The rapeseed hulls had no noticeable effect on digestibility.

COMPOSITION AND DIGESTIBILITY BY PIGS OF HULL FRACTIONS FROM RAPESEED CULTIVARS WITH YELLOW OR BROWN SEED COATS

Hull fractions from yellow seed (Brassica campestris 'R-500') and brown seed (Brassica napus 'Tower') cultivars of rape were fed to pigs at levels of 0, 15 and 30% of the diet in a digestibility trial. Whole seed, 'meats' (embryo) and hull fractions were analyzed for moisture, protein, ether extract, crude fiber, neutral and acid detergent fiber, lignin, ash, calcium, phosphorus, sinapine, glucosinolates and gross energy. Brown hulls contained more fiber and lignin. The embryo content of the yellow hulls fraction was greater than that of the brown hulls fraction. Increasing dietary levels of hulls depressed digestibility of dry matter, energy, crude fiber and ether extract. Brown hulls had the greatest effect. The effect on ether extract digestibility may have been due to lower digestibility of unextracted oil in embryo fractions adhering to hulls. The digestibility coefficients of Tower and R-500 added oils were 87 and 75%, respectively, and the same oils residing in the meats were 36 and 44% digestible. The energy components of hulls per se were more digestible in R-500 than in Tower. Protein of Tower hulls was indigestible, but R-500 hull protein was about 20% digestible. Key words: Rapeseed hulls, yellow brown, composition, digestibility, pigs

TANNIN AND FIBER CONTENTS OF RAPESEED AND CANOLA HULLS

Hulls from rapeseed and canola seed were analyzed for tannins, and the ability of these tannins to inhibit α-amylase in vitro was determined. Extractable tannin content ranged from 0.02 to 0.22%. The α-amylase inhibition test showed zero values for rapeseed and canola hulls indicating the absence of tannins capable of inhibiting this enzyme. Key words: Tannins, polyphenolics, canola, hulls, fiber, lignin

NUTRITIONAL EVALUATION OF MEALS AND MEAL FRACTIONS DERIVED FROM RAPE AND MUSTARD SEED

Low glucosinolate rapeseed meal (RSM) (B. napus 'Bronowski'), rapeseed meal fractions (hulls, detailed meal, dehulled and water-washed meal, lyophilized water extract) derived from Bronowski and from a high glucosinolate rapeseed (B. napus 'Oro'), yellow mustard (B. hirta) hulls and meal were subjected to chemical and nutritional evaluations. Oat hulls and soybean meal were included for comparison. Proximate, amino acid and glucosinolate analyses and feeding experiments were conducted. The processed meals, hulls and extracts were included in diets to provide 8, 12 and 16% dietary crude protein in conjunction with a purified basal fraction containing 5% casein. The toxic effects of glucosinolates fed with active myrosinase were confirmed. Glucosinolates included in soybean meal (SBM) control diets were innocuous. Removal of rapeseed hulls increased digestible (DE) and metabolizable energy (ME) and digestible crude protein contents, but the inclusion of the hulls in high energy, non-rapeseed meal (RSM) diets had no adverse effects on growth of mice or efficiency of feed utilization. Dehulled RSM had lower DE than SBM, partly due to lower digestibility of the non-hull, non-protein energy fraction. Dehulling increased the protein content of RSM, decreased the lysine content of the protein and improved the digestibility of protein. Protein quality tests (Protein Efficiency Ratio and Apparent Biological Value) showed protein of RSM to be equal to that of soybean meal.