Effect of the desolventizing/toasting process on chemical composition and protein quality of rapeseed meal

Heat-induced pressed gels from canola press cakes: Exploring the impact of starting materials, stirring conditions, and carbohydrase pretreatment

Alternative plant protein sources offer excellent solutions for tackling the current challenge of food insecurity and sustainability. Inspired by soy tofu, pressed gels represent a robust and versatile way to create protein-enriched plant products. Here, production of heat-induced pressed gels from canola cold-pressed cakes (CPC) and hot-pressed cakes (HPC) was investigated under varied stirring conditions. Pressed gels prepared from CPC resulted in a greater yield and protein recovery than that of HPC. While using carbohydrases as a pretreatment was ineffective in improving yield and protein recovery, applying a stirring condition during heating increased the protein recovery up to 38.3%. Also, stirring condition was proved to be able to modulate the textural properties by controlling the compactness and the size of aggregates. It is revealed that pressed gels are stabilized through a combination of hydrogen bonds, hydrophobic interactions, and disulfide bonds. In comparison to canola press cake, the pressed gels contained less glucosinolates and phenolic compounds, but more phytic acid. A mechanism of formation has been hypothesized based on the nucleation-growth mechanism, and a shift was proposed from diffusion-limited processes in non-stirred pressed gels to reaction-limited process in stirred pressed gels. In conclusion, the potential of canola heat-induced pressed gels was demonstrated both as a stand-alone product and a micro-structured protein extract.

A Novel Approach about Edible Packaging Materials Based on Oilcakes-A Review

Due to the growing global population and subsequent environment degradation, as well as changes in the climate, changing consumers' dietary habits is necessary to create strategies for the most efficient use of natural resources to eliminate waste in the food supply chain. The packaging of food is essential to preserve the food's properties, extend its shelf life and offer nutritional information. Food products are packaged in various materials of which the most used are plastics, but they have a negative impact on the environment. Various efforts have been made to address this situation, but unfortunately, this includes recycling rather than replacing them with sustainable solutions. There is a trend toward edible packaging materials with more additional functions (antioxidant, antimicrobial and nutritional properties). Edible packaging is also a sustainable solution to avoid food waste and environment pollution. Oilcakes are the principal by-products obtained from the oil extraction process. These by-products are currently underused as animal feed, landfilling or compost. Because they contain large amounts of valuable compounds and are low-cost ingredients, they can be used to produce materials suitable for food packaging. This review covers the recent developments in oilcake-based packaging materials. Special emphasis is placed on the study of materials and technologies that can be used to make edible film in order to research the most suitable ways of developing oilcake-based film that can be consumed simultaneously with the product. These types of materials do not exist on the market.

Mild Fractionation for More Sustainable Food Ingredients

With the rising problems of food shortages, energy costs, and raw materials, the food industry must reduce its environmental impact. We present an overview of more resource-efficient processes to produce food ingredients, describing their environmental impact and the functional properties obtained. Extensive wet processing yields high purities but also has the highest environmental impact, mainly due to heating for protein precipitation and dehydration. Milder wet alternatives exclude, for example, low pH-driven separation and are based on salt precipitation or water only. Drying steps are omitted during dry fractionation using air classification or electrostatic separation. Benefits of milder methods are enhanced functional properties. Therefore, fractionation and formulation should be focused on the desired functionality instead of purity. Environmental impact is also strongly reduced by milder refining. Antinutritional factors and off-flavors remain challenges in more mildly produced ingredients. The benefits of less refining motivate the increasing trend toward mildly refined ingredients.

Feed Clusters According to In Situ and In Vitro Ruminal Crude Protein Degradation

Effective degradation (ED) of crude protein (CP) was estimated in vitro at 0.02, 0.05 and 0.08 h−1 assumed ruminal passage rates for a total of 40 feedstuffs, for which in situ ED was available and used as reference degradation values. For this, the Streptomyces griseus protease test was used. The differences between in vitro CP degradation and the in situ CP degradation values were lowest in legume grains and highest in cereal by-products and barley. The differences between in situ and in vitro ED were expressed using a degradation quotient (degQ), where degQ = (EDin vitro − EDin situ)/EDin situ. Among the tested feedstuffs, eight specific clusters were identified according to degQ for the assumed passage rates. The feedstuffs clustered in an unspecific way, i.e., feedstuffs of different nutrient composition, origin or treatment did not necessarily group together. Formaldehyde−treated rapeseed meal, soybean meal, wheat, a treated lupin, sunflower meal and barley could not be assigned to any of the clusters. Groupwise degradation (range of degQ for assumed passage rates are given in brackets) was detected in grass silages (−0.17, −0.11), cereal by-products together with sugar beet pulp (−0.47, −0.35) and partly in legume grains (−0.14, 0.14). The clustering probably based on different specific nutrient composition and matrix effects that influence the solubility of feed protein and limit the performance of the protease. The matrix can be affected by treatment (chemically, thermally or mechanically), changing the chemical and physical structure of the protein within the plant. The S. griseus protease test had reliable sensitivity to reflect differences between native feedstuffs and treatments (thermally or chemically) that were found in situ. The in situ results, however, are mostly underestimated. The clustering results do not allow a clear conclusion on the groupwise or feed-specific use of carbohydrate-degrading enzymes as pre- or co-inoculants as part of the S. griseus protease test and need to be tested for its potential to make this test more conform with in situ data.

Biotransformation technology and high-value application of rapeseed meal: a review

Rapeseed meal (RSM) is an agro-industrial residue of increased functional biological value that contains high-quality proteins for animal feed. Due to the presence of antinutritional factors and immature development technology, RSM is currently used as a limited feed additive and in other relatively low-value applications. With increasing emphasis on green and sustainable industrial development and the added value of agro-industrial residues, considerable attention has been directed to the removal of antinutritional factors from RSM using high-efficiency, environment-friendly, and cost-effective biotechnology. Similarly, the high-value biotransformations of RSM have been the focus of research programmes to improve utilization rate. In this review, we introduce the sources, the nutrient and antinutrient content of RSM, and emphasize improvements on RSM feed quality using biological methods and its biotransformation applications.

Rapeseed meal as a feed component in monogastric animal nutrition – a review

Rapeseed is an important oil crop worldwide, with an annual production of more than 70 million tons. Rapeseed meal (RSM) is a by-product of rapeseed oil production and is second after soybean meal (SBM) in the world production of protein meal. Rapeseed meal derived from black-seeded winter oilseed rape (Brassica napus L.) usually contains between 35 and 40% of crude protein (CP), which is considered to be one of the more valuable plant proteins. It has a good balance of essential amino acids and a very high protein efficiency ratio (PER=3.29). However, full utilisation of this protein is difficult due to presence of the non-protein components of the seed which are associated with it. These are called antinutritional factors and they limit the utilisation of RSM in monogastric animal nutrition. The main antinutritional factors in RSM are dietary fibre, glucosinolates, phytic acid, and phenolic compounds (sinapine, tannins). For many years, research has been conducted in many centers around the world to improve the nutritional value of RSM, which will consequently increase its use in feeding monogastric animals. The attempts that have been undertaken include breeding strategy, optimisation, modernisation and better control of the oil extraction process, as well as technological treatments of seeds and meal. This review provides information on how RSM has evolved in recent years, as well as on its nutritive value, particularly protein, fibre and glucosinolate content. Techniques which have been used to improve the nutritional value of rapeseed products are also discussed. However, the used methods do not allow for full replacement soybean meal by RSM in monogastric animal nutrition.

In situ ruminal disappearance of crude protein and phytate from differently processed rapeseed meals in dairy cows

BACKGROUND

The influence of different processing conditions of rapeseed meal on ruminal degradation of crude protein and phytate in dairy cows was investigated. Following oil extraction from the rapeseed, five residence times in the desolventizer/toaster were chosen to remove the solvent from the meal. Rapeseed cake and rapeseed meals were incubated in situ in the rumen of three fistulated dairy cows to determine ruminal degradation parameters.

RESULTS

With increasing residence time in the desolventizer/toaster the ruminal degradation of crude protein decreased significantly for every treatment step. Ruminal phytate degradation and crude protein degradation were affected almost identically.

CONCLUSION

The processing conditions of rapeseed meal have a major impact on the ruminal degradation of crude protein and phytate, indicating a potential conflict of interest regarding the production process. Large amounts of undegradable rumen protein are often intended for high-yielding dairy cows whereas a high level of ruminal degradation is preferred for phytate to increase absorption of phosphorus in the small intestine. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Breeding Canola (Brassica napus L.) for Protein in Feed and Food

Interest in canola (Brassica napus L.). In response to this interest, scientists have been tasked with altering and optimizing the protein production chain to ensure canola proteins are safe for consumption and economical to produce. Specifically, the role of plant breeders in developing suitable varieties with the necessary protein profiles is crucial to this interdisciplinary endeavour. In this article, we aim to provide an overarching review of the canola protein chain from the perspective of a plant breeder, spanning from the genetic regulation of seed storage proteins in the crop to advancements of novel breeding technologies and their application in improving protein quality in canola. A review on the current uses of canola meal in animal husbandry is presented to underscore potential limitations for the consumption of canola meal in mammals. General discussions on the allergenic potential of canola proteins and the regulation of novel food products are provided to highlight some of the challenges that will be encountered on the road to commercialization and general acceptance of canola protein as a dietary protein source.

Investigations into the chemical composition and nutritional value of single-cultivar rapeseed meals for broiler chickens

A study was conducted to 1) investigate the influence of rapeseed cultivar on the range of variation in the chemical composition and feed value of rapeseed meals (RSM) for broilers and 2) to compare between single-cultivar RSM and a batch of UK-sourced proprietary rapeseed meal. Chemical composition was determined for a total of 10 single-cultivar RSM produced via prepressed solvent-extraction and a proprietary RSM. To investigate RSM digestibility a total of 360 birds were housed, six birds per pen, and between day 13 to 21 of age they received a diet containing per kg 250 g RSM and 750 g basal feed based on wheat and soybean meal. Titaniumdioxide (7 g/kg) was added as an inert marker. For the determination nitrogen-corrected metabolisable energy (AMEn) total excreta and feed intake were quantified over the last 4 d of the experiment. On the final day of the experiment ileal digesta were collected for determination of preceacal crude protein digestibility (pcCPD). With the exception of neutral detergent fibre (NDF), glucosinolates and soluble non-starch polysaccharides the coefficients of variation (CV%) for all major components were similar across all RSM (0.5 < CV% < 0.6). Glucosinolate contents were highest in the 10 single-cultivar RSM whereas NDF levels were greater in the proprietary RSM. Across the 10 single-cultivar RSM there was no significant effect of cultivar on AMEn or pcCPD. Pre-planned orthogonal contrasts indicated that the mean AMEn content and pcCPD of the proprietary RSM was significantly lower than the 10 single-cultivar RSM (p < 0.001). In view of the above, processing rather than cultivar appears to be the main driver of nutritional value in RSM fed to broilers.

Extrusion Processing of Rapeseed Press Cake-Starch Blends: Effect of Starch Type and Treatment Temperature on Protein, Fiber and Starch Solubility

For the valorization of oilseed press cakes into food products, extrusion can be used. A common way of applying the protein- and fiber-rich press cakes in directly expanded products is the combination thereof with starch, since starch gives a favourable texture, which correlates directly to expansion. To control product properties like expansion of protein and fiber-rich extruded products, the underlying physicochemical changes of proteins, fibers and starch due to thermomechanical input need to be comprehensively described. In this study, rapeseed press cake (RPC) was extruded and treated under defined thermomechanical conditions in a closed-cavity rheometer, pure and in combination with four starches. The impact of starch type (potato PS, waxy potato WPS, maize MS, high-amylose maize HAMS) and temperature (20/25, 80, 100, 120, 140 °C) on protein solubility, starch gelatinization (D_gel), starch hydrolysis (S_H) and fiber solubility of the blends was evaluated. The extrusion process conditions were significantly affected by the starch type. In the extruded blends, the starch type had a significant impact on the protein solubility which decreased with increasing barrel temperature. Increasing barrel temperatures significantly increased the amount of soluble fiber fractions in the blends. At defined thermomechanical conditions, the starch type showed no significant impact on the protein solubility of the blends. Therefore, the observed effects of starch type on the protein solubility of extruded blends could be attributed to the indistinct process conditions due to differences in the rheological properties of the starches rather than to molecular interactions of the starches with the rapeseed proteins in the blends.

Comparison between the effects of feeding copper sulphate-treated and untreated rapeseed cake containing high glucosinolates on rumen fermentation, nutrient digestion and nitrogen metabolism in steers

Two trials were carried out to study the effects of copper sulphate (CuSO₄ ) on detoxifying glucosinolates (GLS) in rapeseed cake (RSC) and compare the effects of feeding CuSO₄ -treated and untreated RSC on nutrient digestion and nitrogen (N) metabolism in steers. In Trial 1, different concentrations of CuSO₄ solution (1.6 vs. 3.2 g CuSO₄ ·5H₂ O L^-1 ), soaking temperatures (25 vs. 60°C) and drying methods (air drying at 60°C vs. freeze drying) were allocated in a 2 × 2 × 2 factorial arrangement in vitro. In Trial 2, six steers and dietary inclusions of untreated RSC (control), CuSO₄ -treated RSC and CuSO₄ -added RSC were assigned in a replicated 3 × 3 Latin square design. CuSO₄ treatment in vitro decreased the contents of GLS and thiocyanate (TC) in RSC (p < 0.001). The total amount of GLS and TC decreased by 62.7-68.5% for all treatments. The animal trial showed that CuSO₄ -treated RSC inclusion decreased ruminal concentration of valerate (p < 0.01), whereas it did not affect ruminal pH, ammonia N and total volatile fatty acids. Compared with the control, feeding CuSO₄ -treated or CuSO₄ -added RSC had no effect on plasma concentrations of triiodothyronine and thyroxine, N excretion and N retention. CuSO₄ -treated RSC tended to increase neutral detergent fibre digestibility (p = 0.072) and urinary excretion of urea (p = 0.056). Urinary excretion of purine derivatives (p = 0.076) and rumen microbial N supply (p = 0.084) tended to decrease when feeding CuSO₄ -treated RSC versus control. TC was found to be the only metabolite of GLS in rumen fluid, plasma and urine. It was feasible to detoxify GLS in RSC using low CuSO₄ at room temperature. However, feeding CuSO₄ -treated or CuSO₄ -added RSC had minor effects on rumen fermentation, nutrient digestion and N metabolism in steers. CuSO₄ treatment on RSC for feeding steers seems to be unnecessary.

The effects of processing barley and maize on metabolic and digestive responses in horses

The competition for customers increases the search for new grain processing methods for equine feed, but the effect on starch digestibility and metabolic responses varies. Therefore, to evaluate the effect of the processing methods, toasting and micronizing, on starch digestion and the effect on metabolic responses, the mobile bag technique (MBT) and plasma glucose and insulin concentrations in the blood were used to estimate nutrient disappearance and metabolic responses pre-cecally. Further, cecal pH, ammonium nitrogen (N), and short-chain fatty acid (SCFA) concentrations were used to estimate the metabolic response in the cecum. Four cecally cannulated horses (body weight [BW] 565 ± 35 kg) were used in a 4 × 4 Latin square design with four periods of 8 d of diet adaptation and 2 d of data collection. Diets were formulated using hay and processed grains: micronized barley (MB), toasted barley (TB), micronized maize (MM), and toasted maize (TM) and were balanced to provide 1 g starch/kg BW in the morning meal. On day 9 in each period, blood and cecal fluid samples were taken before the morning meal and hourly thereafter for 8 h. On day 10 in each period, 15 bags of either MB, TB, MM, or TM (1 × 1 × 12 cm; 15 μm pore size; 1 g feed) were placed in the stomach, respectively. The dry matter disappearance was highest for the MM at all time points compared with the other feedstuffs (P < 0.001). Maize and micronizing had the highest starch disappearance (P = 0.048) compared with barley and toasting. No treatment effect was measured for any of the glucose and insulin parameters. No feed effect was measured for the insulin parameters. Plasma glucose peaked later (P = 0.045) for maize than for barley, and TB had a larger area under the curve for glucose than MB, MM, and TM (P = 0.015). The concentration of total SCFA increased after feeding (P < 0.001), with a higher concentration for barley than for maize (P = 0.044). No treatment or feed effects were measured for ammonium N or pH, but both were affected by time (P < 0.001). In conclusion, toasting was not as efficient as micronizing to improve pre-cecal starch digestibility; therefore, the preferred processing method for both barley and maize is micronizing. Further, the amount of starch escaping enzymatical digestion in the small intestine was higher than expected.

Oil Press-Cakes and Meals Valorization through Circular Economy Approaches: A Review

The food industry generates a large amount of waste every year, which opens up a research field aimed at minimizing and efficiently managing this issue to support the concept of zero waste. From the extraction process of oilseeds results oil cakes. These residues are a source of bioactive compounds (protein, dietary fiber, antioxidants) with beneficial properties for health, that can be used in foods, cosmetics, textile, and pharmaceutical industries. They can also serve as substrates for the production of enzymes, antibiotics, biosurfactants, and mushrooms. Other applications are in animal feedstuff and for composites, bio-fuel, and films production. This review discusses the importance of oilseed and possible valorization methods for the residues obtained in the oil industry.

The effects of supercritical carbon dioxide extraction and cold-pressed hexane extraction on the chemical composition and feeding value of rapeseed meal for broiler chickens

The chemical characteristics of rapeseed meal (RSM) produced from two cultivars of UK-grown rapeseed, by both supercritical carbon dioxide extraction (ScCO₂) and cold-pressed hexane extraction (CpHe) were examined. Their nutritional value, with and without protease, was then assessed in a broiler digestibility trial. Basal feed was substituted with one of four RSM batches (200 g/kg) following adjustments for dry matter (DM) and ether extract (EE) content. Half of each diet was supplemented with a mono-component protease derived from Bacillus subtilis (Axtra®PRO, Danisco Animal Nutrition, Malborough, UK) giving a total of eight test diets. Two control diets, with and without protease were also fed. At 13 d age male Ross 308 broilers were randomly allocated to seven replicate pens (five birds per pen) and assigned to one of 10 diets. Total excreta were collected from 17 to 21 d age and feed intake was recorded. Pre-caecal protein digestibility (pcPd) was determined using TiO₂ as an indigestible marker. Colourimetrically CpHe RSM was substantially darker than ScCO₂ counterparts. The influence of oil recovery method (ORM) was also evident in DM, EE, ash free neutral detergent fibre (aNDFom), neutral detergent insoluble crude protein (NDICP) and glucosinolate content (GLS). The content of DM, EE and GLS was higher in ScCO₂ RSM whereas aNDFom and NDICP levels were greater in CpHe RSM. Protein solubility in KOH was greater in ScCO₂ RSM whilst levels of NDICP were lower. Collectively these results suggest that less heat damage was incurred to the RSM during ScCO₂ extraction. There was no significant main effect of cultivar nor were any significant interactions observed between treatment factors. Rapeseed meal ScCO₂ produced greater metabolisable energy, pcPd, nitrogen retention and energy metabolisability (p < 0.05). Protease supplementation increased pcPd (p < 0.05) irrespective of ORM and cultivar. The key implications of these findings are that by adopting oil recovery methods that minimise the exposure of RSM to thermal treatments and by adding a compatible protease there is scope to increase the nutritional value of RSM for broilers and increase its utilisation in modern poultry production.