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Carlson, K.D., J.C. Gardner, V.L. Anderson, and J.J. Hanzel. 1996. Crambe: New crop success. p. 306-322. In: J. Janick (ed.), Progress in new crops. ASHS Press, Alexandria, VA.

Crambe: New Crop Success*

Kenneth D. Carlson, John C. Gardner, Vernon L. Anderson, and James J. Hanzel

    1. HEADE Origination
    2. Management and Operation
    1. Early Attempts at Commercialization
    2. North Dakota Commercialization
    3. Production Practices
    4. Production Problems and Opportunities
    5. Market Size and Familiarity
    1. A Question of Markets
    2. Defining the Product
    3. Meal Efficacy
    1. Past Breeding Efforts
    2. Current Objectives
    3. Breeding Approaches
    4. Recent Progress
  8. Table 1
  9. Table 1
  10. Table 2
  11. Table 3
  12. Table 4
  13. Table 5
  14. Table 6
  15. Table 7
  16. Table 8
  17. Table 9
  18. Table 10

Crambe was commercialized in the 1990s through the efforts of a dedicated team of farmers, agribusiness people, and scientists to develop a reliable domestic supply of erucic acid. Crambe (Crambe abyssinica), a plant of Mediterranean origin, produces an abundance of erucic acid in its seed oil. Erucic acid has an established market in erucamide, a preferred slip and antiblock agent for polyolefin films. In 1990, North Dakota farmers teamed up with National Sun Industries (NSI) and North Dakota State University (NDSU) to produce 900 ha of crambe, and within four years that team had nearly 24,000 ha of crambe under cultivation. NSI crushed the seed in their Enderlin, ND, mill and marketed the oil and the coproduct defatted seed meal. Concurrently, the High Erucic Acid Development Effort (HEADE) team sponsored and conducted production, breeding, processing, product development, and marketing research, including critical feeding experiments at NDSU that affirmed the efficacy of using crambe meal in beef rations. Crambe was fed at up to 16.9% of diet dry matter to growing steers and at 4.2% to finishing steers. In creep feeds, crambe was included at up to 10% of the diet, and was supplemented at up to 9% of dry matter intake in cow rations. No pattern of significant effects was observed on intake, digestibility, blood metabolites, thyroid hormones, or performance of animals due to increasing levels of crambe meal. Acceptance of crambe meal by commercial feed companies and feeders was based both on attractive price and satisfactory animal performance. Objectives of a crambe breeding program established at NDSU include higher yielding cultivars, with more oil and erucic acid, with lower seed glucosinolate content, and with improved plant resistance to diseases, insects and seed shatter. Genotypes that perform better than currently grown varieties in all desirable traits have been identified, as have several lines with acceptable levels of glucosinolates in the meal. The HEADE approach to commercializing crambe probably can be applied to the development of other new crops, especially when modeled with a regional perspective. The importance of a strong market pull and dedicated private sector partners cannot be over emphasized. A crambe growers group currently has commitments that will enable sustainable production while new markets for the seed oil and meal are developed.


Since the end of WWII, U.S. agriculture's splendid capacity to overproduce has been apparent to even the most casual observer. Multidisciplinary research and America's unmatched capacity for technology development and efficient transfer of that technology to all sectors of the agricultural community contributed to making the U.S. the food basket of the world. Even with huge outlays of money, J. Janick and J.E. Simon (eds.), various combinations of support programs have been only partly successful in matching production capabilities with market demand and in maintaining profitability for the producers of the major commodities.

Efforts to replace some commodity acreage with specialty food crops have succeeded because of the pull of the market place and consumer acceptance of new foods. However, attempts to introduce new industrial crops, i.e., those with non-food uses, have been very slow, often haphazard, and inefficient. Intentional efforts in the last ten years to create new industrial crops and to discover new industrial uses for existing commodity crops have met with a modicum of success, acceptance, and support. More movers and shakers are seeing the value of this effort in reducing commodity surpluses while maintaining a strong agricultural economy and undergirding an industrial infrastructure for the future.

One small piece of this effort was advanced at a conference in Kansas City, MO, in December 1986, when a small group of university scientists, private sector representatives, and government scientists and managers focused on rapeseed and crambe (Crambe abyssinica) as candidate industrial crops for the U.S. (Carlson and Van Dyne 1992). Both crops produce seed oils rich in erucic acid (EA), which is used to manufacture a key additive for the plastics industry, erucamide, a slip and anti-block agent critical to manufacture and use of polyolefin films. Plastic films such as polyethylene are produced in a plethora of forms for such familiar items as bread wraps, shopping and garbage bags, and shrink wraps and plastic sheeting for an array of commercial applications. At the time of the Kansas City meeting, domestic needs for erucic acid were entirely satisfied by imports of high erucic acid rapeseed (HEAR) oil, originating largely in northern and eastern Europe and in Canada. This niche industrial market for high erucic oils had been known for over 20 years. As a source of edible oil, HEA (industrial) rapeseed had been introduced on a large scale to the North American continent in the 1960s and 1970s through the splendid research of Canadian agricultural scientists. Their equally elegant research converted the crop (1970s and 1980s) to low erucic acid cultivars (LEAR) and ultimately to canola cultivars without significant erucic acid content. With the widespread acceptance of LEAR and canola worldwide, HEAR oil appeared to be moving from a widely available commodity oil to a contracted specialty oil.

By December, 1986, the University of Idaho and the U.S. Department of Agriculture had conducted substantial research on rapeseed and crambe, respectively, and came to Kansas City with significant data bases relating to the production of the two crops in the U.S. However, annual production of several thousand ha of HEAR in Idaho, which was marketed to Pacific Rim countries, and very sporadic production of crambe, though funneled to domestic erucamide producers, had failed to instill confidence in either crop's reliability as a domestic source of erucic acid. Faced with a rather dismal marketing and production track record, participants at the meeting still recognized the potential of, and critical need for, erucic acid's industrial niche, and the significance of developing a domestic source of erucic acid. Thus was laid the groundwork for a high erucic acid development effort (HEADE), which would evolve into an informal consortium of university scientists, industry participants and government scientists and managers focused as a team on the commercialization of crambe and industrial rapeseed as domestic sources of erucic acid.


HEADE Origination

The U.S. Department of Agriculture, through its Cooperative State Research, Education, and Extension Service's (CSREES) Office of Agricultural Materials and its Agricultural Research Service's (ARS) National Center for Agricultural Utilization Research (NCAUR), and the University of Missouri's Department of Agricultural Economics were instrumental in organizing the Kansas City meeting. They, along with Iowa State and Kansas State Universities and the Kansas Board of Agriculture, provided leadership for establishing initial management structure, setting goals and developing action plans, primarily for commercializing crambe. In 1989, the "crambe project" sponsored a crush of about 150 t of crambe seed produced in Iowa and successfully marketed the oil, which immediately heightened both public and private sector interest in high erucic oils. In 1990, the project was broadened to include industrial rapeseed when several additional universities joined the project, HEADE was born, and its management structure was functionally established. A key event that year occurred when National Sun Industries of Minneapolis, MN, committed to commercializing crambe and worked closely with the North Dakota State University (NDSU) Research Extension Center and HEADE from 1990 to 1995.

Table 1 lists the institutional partners and some areas of expertise that they brought to the HEADE project during the period 1986-95. Contributions made by each institution depended on the disciplines of numerous individual scientists, and ranged from chemistry, biochemistry and engineering to multiple aspects of plant, insect, and animal sciences to crop production and oilseed processing to technology transfer, marketing, and economics. Each contribution was critical to the evolutionary path that HEADE took in successfully bringing crambe to significant commercial production.

Management and Operation

HEADE functioned under a Management Committee consisting of the state experiment station directors (or their representatives) and two USDA designates. The Management Committee elected a chairperson and appointed a project coordinator, who together established agendas, conducted regular meetings of the Committee, and coordinated and oversaw HEADE activities between meetings. Subcommittees, consisting of multidisciplinary teams of scientists, directed HEADE-approved activities involving production, processing and co-products, and marketing and economics. Committee functions and responsibilities are summarized in Table 2.

An annual line item appropriation from the Congress provided partial funding for HEADE activities (<$500,000). The funds were administered through the CSREES Office of Agricultural Materials (USDA) to the participating universities under cooperative agreements.

Each member university also provided funds and in-kind support for the research and commercialization projects. The HEADE management committee established RFP (request for proposals) and peer review procedures (filtered through the subcommittees) to select 15 to 20 projects for funding each year.

When line item funding for HEADE ended in FY 95, the HEADE management committee completed remaining funded research projects, and encouraged project members to continue their institutional commitments to crambe and rapeseed commercialization. Internal funding and development of cooperative interactions with seed, biotech and chemical companies and with growers groups have enabled several universities to continue breeding, agronomic, animal feeding, and chemical research on crambe and rapeseed. For example, North Dakota State University and the Universities of Georgia, Idaho, and Nebraska are funding projects through their plant and animal sciences, chemistry and engineering, and extension departments. Numerous companies and private sector individuals formally and informally partnered with HEADE, and their contributions were especially important to HEADE's decade of work to commercialize high erucic acid crops. The discussion that follows covers HEADE efforts on crambe seed production, meal utilization and renewed breeding studies.


Though natives to the Middle-east, rapeseed (both Brassica napus and B. campestris) and crambe (Crambe abyssinica) have emerged as commercially viable crops adapted to a broad range of growing regions in the U.S. and world. Between the two crops there exists winter and spring growth habits, a variety of pest resistance mechanisms, the ability to enhance rotations with traditional crops, and potential to better conserve soil resources, all ecological characteristics important to their success. Older EA-containing rapeseed varieties are being replaced world wide by canola types (no EA), because of the latter's popularity in the edible oil markets. EA-containing rapeseed varieties now are specialty crops in Canada and Europe. In the U.S., industrial rapeseed was the dominant HEA non-food oilseed before 1990, when its acreage was largely replaced by canola, and crambe became the dominant HEA crop.

In comparison to the cultivation of rapeseed, which is usually dated to the 20th century BC, crambe was introduced a little more than 50 years ago through a coordinated network of federal, state, and private interests. While still far from being considered a common crop, its path from potential crop designee to commercial production in such a short period of time has made crambe an interesting case in new crop development. During the rapid increase in crambe production in the 1990s, scientists at NDSU strove to reach beyond traditional small plot research to better identify why and how farmers respond to new crops, which ultimately determines whether they will be successfully incorporated into new farming systems.

Early Attempts at Commercialization

Crambe has been evaluated as a potential oilseed crop since about 1932 (Hirsinger 1989). Interest first surfaced in the U.S. in 1957 when the USDA began a program of systematically screening a large number of plant species as potential new crops (Wolff and Jones 1958; Princen 1983). Among some 8,000 species evaluated by NCAUR between 1957 and 1983, crambe emerged as a promising oilseed crop due to its high content of erucic acid. This long-chain fatty acid has many potential industrial uses including use as lubricants, coatings, slip-agents, plasticizers, polymers, and nylon precursors (Carlson and Van Dyne 1992).

Since this early promise was identified, various state and federal agencies have evaluated crambe for brief periods. North Dakota investigated crambe at several research centers in the late 1960s and early 1970s. Hoag and Geiszler (1970) reported a five year mean yield at Minot, ND, on fallow of 1698 kg ha-1. At Williston, ND, on dryland, a mean yield of 842 kg ha-1 was obtained during the same 1965-1969 period. In reporting results with crambe, North Dakota was no different than several other state and national efforts at the time, all exploring production feasibility (White and Higgins 1966). The majority of production research, however, came from the Midwest cornbelt and was championed by breeder Koert Lessman at Purdue University (Lessman and Meier 1972). Crambe appeared drought tolerant, widely adapted, and among the most promising of several potential new crops.

As with most crops, coordinating and balancing supply with demand has historically been a problem with crambe. The USDA initiated field production of crambe for several years in the late 1970s to build seed supply. This effort ultimately led to the first private sector promoted attempt to commercially produce crambe (Princen 1983). In the spring of 1981, 405 ha of crambe were contracted with Humko (now Witco Chemical Co.) to be grown in western Kentucky (Durwood Beatty pers. commun.). A price of 25 cents per kg-1 was agreed upon and the crop was seeded in March with the hopes of a late June or early July harvest in time to double crop soybeans. The warm, dry spring gave crambe a good start, but also resulted in a wide-spread aphid epidemic, which destroyed ca. 80% of the crambe plantings. Harvested seed was destroyed in a warehouse fire later that year. Such an egregious result left little private sector interest in crambe, and some observers at the time of the Kansas City meeting in Dec., 1986, questioned the wisdom of advancing the cause of high erucic acid crops for the U.S. However, others believed that a systems approach to breeding, production, processing and marketing of both industrial rapeseed and crambe was not only appropriate but a right avenue to successful domestication (Carlson and Van Dyne 1992).

North Dakota Commercialization

By 1990, HEADE promoted research showed that crambe seemed particularly viable in North Dakota. Commercialization was again attempted in the spring of 1990 by spreading responsibilities and risks via a three way partnership of HEADE, National Sun Industries (NSI, an oilseed processor at Enderlin, ND), and thirty-eight North Dakota farmers. HEADE, through NDSU's Research and Extension Center in Carrington, solicited farmers in central North Dakota to grow crambe, provided 'Meyer' crambe seed and production information to the growers, and served as a communications link between the farmers and NSI. Farmers delivered the crop to NSI's Enderlin plant within a narrow window timed to coordinate with NSI's other oilseed deliveries. NSI paid farmers for the seed upon delivery and inspection (16.5 to 23.1 cents per kg). Following recommendations based on previous USDA Research (Carlson et al. 1985), NSI processed the seed via prepress/solvent extraction technology, and sold the oil and marketed the meal to feed formulators (cattle feed lots).

Successful production of crambe in North Dakota has continued (Table 3), but not without difficulties. NSI's attempts to produce crambe in the Central Great Plains, near Goodland, KS and also in the San Luis Valley of Colorado in 1993 were disappointing, and commercial production of crambe remains concentrated in North Dakota. In North Dakota, production began in the central and eastern portions of the state, but wet conditions during the past few years have moved production west. Today, the three principal growing regions surround the counties of Barnes, Foster, and Stutsman in the central region, Ward in the northwest, and Hettinger in the southwest portions of the state. Despite attempts to balance supply and demand, over-production limited the 1995 crop to seed increase until oil stocks could be consumed. Also, NSI decided to leave the oilseed crushing business, and leased their processing facilities in late 1994. Perhaps as evidence of its success, HEADE also lost its federal funding in 1994. Therefore, North Dakota crambe growers have organized into the American Renewable Oil Association (AROA), which has taken on the responsibilities of crop production, seeking processing facilities, and marketing oil and meal. At the time of this writing, AROA anticipates 16,000 ha of crambe production in 1996 (7-9 million kg of oil).

Production Practices

Given the manner in which crambe has been introduced in North Dakota, unique opportunities have existed for cooperative research among farmers, university researchers, and the private sector processors/marketers. Beyond its HEADE role, NDSU has assisted the farmers with an introduction to crambe as a crop, suggested production alternatives, supplied seed, and been available to help solve specific problems. The university has also helped the processor identify potential growing regions, supplied information on processing the oil, and provided quality information on both the oil and the meal in order for these new products to best seek their true market value.

Through a combination of formal surveys and informal observations, North Dakota crambe production practices have been documented in a series of reports published by NDSU (Gardner 1991-1995). Crambe, usually seeded in May and harvested in Aug., has typically followed a small grain crop in rotation (>85%), but also followed flax, fallow, and various other crops. Most growers rate the crop that followed crambe to have performed equivalent to, or better, than when that crop followed a small grain. Volunteer crambe is manageable in succeeding crops through either use of tillage, herbicides, or a combination of both; however, seed dormancy studies suggest that germination may be delayed for extended periods under field conditions. Crambe has been seeded successfully with a wide variety of planting equipment into tilled and untilled seedbeds. It is nearly always seeded into narrow rows (<20 cm) to increase it's ability to compete with weeds early in the season. Herbicides labeled and used are much the same as those used with canola, with soil-applied dinitroanalines applied pre-plant the most popular. The most troublesome weeds are often those that mature late, once the crambe crop is drying down. Though competition with these weeds may not directly reduce yield, it makes harvest more difficult. Crambe can be swathed to dry in the field, but most growers prefer to harvest crambe direct with combine headers commonly used with wheat. Unlike canola, crambe cannot be swathed before the majority of the seeds are physiologically mature, since erucic acid content of the oil is lower in immature seeds. Crambe stubble is easily managed, and requires little fall tillage. The residue is valuable to reduce wind erosion and is an efficient snow trap during the winter.

In comparison to other Northern Plains crops, crambe is relatively inexpensive to produce. Certified seed costs are generally less than $12 ha-1 for the typical 22 kg ha-1 seeding rate. The fertilizer requirements have been found to be no greater than wheat. Dinitroanaline and post-emergent grass herbicides currently labeled are also among the most inexpensive available. Insecticides have not been needed, since, unlike rapeseed or canola, crambe is resistant to flea beetles, the most troublesome insect pest among crucifers in the Great Plains (Anderson et al. 1992). During a typical harvest, crambe seed does not require drying, and due to it's low test weight, is easily aerated should moisture content need to be reduced for storage. Over all, crambe is easily grown with traditional wheat equipment.

Production Problems and Opportunities

As with most new crops, unanticipated production problems have been the most challenging. Crambe possesses several unique characteristics, which have been the source of the majority of special problems and opportunities.

Low test weight. Crambe, unlike rapeseed and most other crucifers, has each seed encapsulated in its own hull. This reduces test weight by more than 50%, to about 322 kg m-3 (25 lb bu-1). Such a bulky commodity increases the cost of transportation from the farmgate to the processing facility, and misleads the grower in visually estimating dockage, or foreign material, in the harvested seed. During the first year of commercial production, the overall mean dockage content of crambe delivered to the processing plant was 14.8%, significantly adding to already substantial transportation costs of the grower. This initially kept commercial production no further than 240 km from the processing plant. Since 1990, above average rainfall across North Dakota has shifted the production region west to avoid diseases such as Alternaria, which limited production in the eastern portion of the state for the first time in 1992. Greater distance from the processing plant has encouraged the grower organization to arrange for group rail shipments. Limited investigations into farmgate dehulling have been discouraging since it can lead to a reduction in oil yield and quality.

Seed dormancy and quality. Barely domesticated, it is not surprising that crambe exhibits a post-harvest dormancy. Such mechanisms are typical in undomesticated species to improve longevity and success. In an annual crop, however, such a trait makes it difficult to accurately estimate germination percentages and can lead to volunteer plants emerging in the field several years after the crop is harvested. Crambe has suffered from both problems. In addition, with abnormally greater rainfall the last few seasons, Alternaria has been observed among the eastern-most growers. Alternaria can infect the seed, causing a subsequent reduction in germination and vigor when later planted (Kilpatrick 1976). The growers group has responded to these problems through establishment of a network of certified seed growers, regular testing, and encouragement of further research at NDSU and elsewhere (Gutormson et al. 1993).

Pesticide availability. Like all new and minor crops, not only must new growers accept the risk of dealing with an unknown crop, but they must also do it with few, or no, labeled pesticides to help aid in weed, disease, and insect management. Current federal registration policies, and an industry that increasingly limits pesticide development even for the few major crops, combine to put new crops at a significant disadvantage in terms of production risk. Through the coordinated work of federal and state researchers, crambe has been coupled with rapeseed/canola in terms of federal pesticide registration, but this still requires the manufacturers to list the specific oilseed (canola, rapeseed, crambe) on the label (U.S. Govt. 1992). Perhaps foreshadowing a requirement for future new crops, crambe was successfully commercialized, because of its inherent ability to compete with weeds, ward off insects, and escape diseases without help from pesticides.

Market Size and Familiarity

Capturing market share with a new product is always challenging. Crambe has been successful to date because of its premium high erucic acid oil (>55% erucic) in the steady niche market for surfactants and slip agents. Current world consumption of high erucic acid oil is growing, but is still only estimated to be about 57 million kg annually, of which only about 16 million kg is used in the U.S. (Charles Leonard pers. commun.). Even if all domestic consumption were crambe, this would still represent less than 40,000 ha on an annual basis. Producing a unique oilseed on this scale presents difficulty in finding a willing processing partner, especially in North Dakota where the oilseed processing industry operates only large facilities, each capable of processing 40,000 ha of crambe in less than three weeks. In addition to the small crush volume, crambe meal has received slow acceptance by the feeding industry, despite encouraging research (Carlson 1992; Anderson 1993; Anderson et al. 1993a, b). Given these problems, crambe was successfully commercialized in North Dakota because it inherited the right production climate, and had willing partners in the processing industry. Jeff Berkow, President, National Sun Industries, and his able and enthusiastic staff, were champions essential to establishing the crop.


A Question of Markets

National Sun Industries produced tens of thousands of tonnes of crambe meal between 1990 and 1995. Initially, there was general unfamiliarity with crambe meal among animal nutritionists and in the feed industry, in spite of crambe's listing as a feed ingredient by the Association of American Feed Control Officials (AAFCO 1989) and its clearance by FDA for use as a protein supplement in beef cattle rations (Federal Register 1981; Carlson and Tookey 1983). The latter, however, restricted crambe meal to feedlot cattle at only 4.2% of their total ration. This restricted use seriously impacted NSI's ability to market the meal with a reasonable economic return, and the company asked HEADE for help in marketing the meal. HEADE produced a brochure (Carlson 1992) detailing the composition, merits, and uses of crambe meal, which was widely distributed to animal nutritionists and feed manufacturers and formulators to help with the awareness issue. Further, HEADE sponsored and promoted a series of carefully controlled cattle feeding studies with the commercial meal to gather new and specific information on the safe use and economic value of crambe meal (Table 4). As discussed below, these studies all pointed to possibly higher levels of use and wider application of crambe meal in beef cattle rations. The following discussions provide additional research perspective on the use of crambe meal in animal feeds.

Defining the Product

Crambe fruits are borne in single-seeded pods (pericarp), and the pods normally remain intact with the seed when harvested. For various reasons, including partial harvest dehulling and intentional process dehulling, the proportion of pericarp to seed meats can vary significantly as processed in the oilseed mill, and therefore the composition of the defatted meal can also vary. Table 5 shows that the protein content of the whole seed meal contains 22% to 28% protein, whereas partially dehulled meal as produced by NSI in 1991 contained 34 to 35% protein. If completely dehulled, crambe meal contains 48% to 50% protein (Kirk et al. 1966; Mustakas et al. 1968; Baker et al. 1977; Carlson et al. 1985; Anderson et al. 1993b). Crude fiber levels also vary widely with the amount of pod present in the processed seed, from >20% in the whole seed to <10% in fully dehulled seed (Table 5). Mineral composition of 1991 commercial crambe meal (Table 6) shows higher levels of calcium, sulfur, chlorine, cobalt and selenium with lower levels of potassium, iron and copper in comparison to soybean meal (Anderson et al. 1993b). Amino acid composition of crambe meal is compared to soybean meal in Table 7, and has higher levels of sulfur-containing amino acids, cystine and methionine.

As a member of the mustard family of plants, crambe seeds and meal contain several glucosinolates recognized as sources of potentially antinutritional compounds. Similar compounds are responsible for the sharp flavors of certain condiments and food vegetables, such as radish, horseradish, cabbage, brussels sprouts, broccoli, and mustard. Of the glucosinolates in crambe, the major one accounts for ca. 95% of the total and is commonly called epi-progoitrin [(S)-2-hydroxy-3-butenyl glucosinolate]. These compounds and their metabolites may interfere with iodine metabolism by reducing the ability of the thyroid to take up iodine. Most reports conclude that oilseed meals containing glucosinolates reduce feed intake and animal performance when fed to non-ruminant animals, but ruminants tolerate glucosinolates at much higher levels without negative effects. Typical levels of individual and total glucosinolates found in commercially processed crambe meal, and in high and low glucosinolate rapeseed meals, are given in Table 8. Glucosinolate contents of defatted meals produced in the 1990s (50-60 µmol/g) generally were higher than in meals produced in the 1970s (25-45 µmol/g), although harvested 1990s seed had lower glucosinolate contents (90-100 µmol/g) than seed processed in the 1970s (125-155 µmol/g). Also, the one glucosinolate breakdown product consistently found in processed crambe meals, 1-cyano-(S)-2-hydroxy-3-butene, relates to glucosinolate destruction during processing and was present in 1990s meals at levels about one half that found in 1970s meals. These results suggest better process control and milder operating conditions in NSI's Enderlin mill during the 1990s, leading to nutritionally better products (Carlson and Tookey 1983; Carlson et al. 1985).

Meal Efficacy

Digestibility. In vitro digestibility of the organic matter in crambe hulls and meal using rumen fluid varied considerably (Steg et al. 1994). Hulls and whole seed meal were poorly digested at 44.5 and 57.3%, respectively, whereas dehulled seed meal was much more digestible at 85.0%. In situ ruminal organic matter digestibilities for dehulled crambe meal, crambe hulls, rapeseed meal, and soybean meal were 96%, 43%, 85%, and 95%, respectively (Liu 1994; Liu et al. 1994a). Total tract organic matter digestibility for crambe meal and rapeseed meal was reported at 98% and 92%, respectively. Crambe meal organic matter, crude protein and neutral detergent fiber degraded more rapidly in the rumen than soybean meal (Liu 1994; Liu et al. 1994a). However, heat treatment or toasting of crambe meal could substantially decrease rumen degradability. Finally, rate of in situ protein disappearance in the rumen was not different for reciprocal amounts of crambe meal and soybean meal fed as protein supplements with a grass hay diet (Caton et al. 1994).

Crambe meal in ruminant diets. Since growth and profitability of crambe as a crop is limited by commercial acceptance and use of the meal as a feed component, positive results in recent HEADE promoted feedlot trials with commercial meals are highly encouraging (Table 4).

Feeding nearly 900 feedlot cattle in 1990 on the first NSI produced crambe meal, Stock et al. (1993) reported an initial decrease in feed intake, but within 3 days intake was equal to control animals. Slightly more crambe ration was consumed over the first 80 days on feed compared to controls, but slightly less over the last 40 days on feed. Duncan and Milne (1991) reported a 6 day adaptation period by ruminant microflora, which may or may not affect initial feed intake when glucosinolate containing meals are introduced to ruminant diets (Carlson and Breeze 1984; Darroch et al. 1991). Anderson et al. (1993b) found that beef cows offered only crambe meal did not consume it until mixed with as little as equal parts of any other feed, such as corn silage. Enhancing palatability of high glucosinolate meals with flavor enhancers has not been extensively studied, but Ingalls and Sharma (1975) reported a non-significant trend to increased intake with flavor or molasses added to high glucosinolate rapeseed diets. Also, no differences in intake of high glucosinolate rapeseed meal in diets based on grain sorghum were observed in steers (Heidker and Klopfenstein 1990). In addition to blending crambe meal with other feed components, pelleting the rations is important to prevent cattle from sorting diets (Lambert et al. 1970; Perry et al. 1979).

In a 63-day creep feeding trial (Table 4), crambe meal fed as a protein source in creep feed at 0%, 5%, and 10% did not affect feed intake, gain, feed efficiency, or thyroid hormones (T3 and T4) measured in blood serum of nursing beef calves (Anderson and Trautman 1995). Perry et al. (1979) previously observed that younger animals may have a higher tolerance for crambe meal. Comparison with more extensive feeding studies with high glucosinolate rapeseed are useful. Ingalls and Sharma (1975) reported that lactating cows were not affected by feeding high glucosinolate rapeseed meal at up to 10% of the diet. Papas et al. (1979) found that feed intake, milk yield, protein, fat, and solids were not affected by replacing soybean meal with rapeseed meal containing either 94 or 50 µmol/g of glucosinolates. However, the higher glucosinolate meal reduced iodine content of the milk and tended to reduce plasma thyroxine in cows. When calves were fed control, low, or high glucosinolate diets, feed intake, weight gain, hemoglobin blood cell volume, and erythrocyte count were unaffected except at the higher glucosinolate levels, which also resulted in more pronounced changes in the thyroids of the calves (Papas et al. 1979).

In two feedlot studies, Anderson et al. (1993a, b) compared four pelleted protein supplements using crambe meal as the protein source to replace 0%, 33%, 67%, or 100% of soybean meal. No differences were observed in feed intake, feed conversion, or rate of gain during an 84-day growing period with crambe meal fed at a maximum of 16.9% of dry matter intake and a 96-day finishing period with crambe meal fed at a maximum of 4.1% of dry matter intake (Table 9, combined feeding results). The growing period study utilized the highest published use level for crambe meal in preparing beef cattle for finishing at the prescribed FDA level of 4.2%. Beef cattle showed no adverse response to crambe meal at levels up to 8.5% in a previous study by Perry et al. (1979), using what is believed to have been a nutritionally inferior meal to the commercial meal used by Anderson et al. (1993a, b).

Earlier research, to support the petition to FDA to clear crambe meal for use in beef cattle rations (Federal Register 1981), determined that no glucosinolate products accumulated in beef fat or tissues (to 1 ppm) when dehulled, defatted crambe meal was fed to steers at 10% of their diets (Van Etten et al. 1977).

Effect of crambe meal on reproduction. Higher levels (25% to 32%) of crambe meal were used in yearling heifer rations than in most feedlot trials without detriment to ovarian cyclic activity or behavioral estrus. Long term studies with postpartum bovines, however, suggest a significant increase in days from calving to conception and increased services per conception with low levels of glucosinolate (31 g/day) in the diet (Cheeke 1987; Cheeke and Shul 1987). Lactating beef cows on 10% crambe meal produced equal calf gains and similar post partum interval to other protein supplement treatments (Anderson 1993). Pregnant ewes have shown no effect from high glucosinolate rapeseed meal on reproduction (Cheeke 1987; Cheeke and Shul 1987).

Implications. Crambe meal as currently produced will continue to be used in ruminant feeds (beef cattle), and be excluded from nonruminant feeds because of reported problems of growth depression, weight loss, toxicity, and organ pathology in monogastric animals (Hesketh et al. 1963; Van Etten et al. 1965, 1969; Fenwick et al. 1983; Wallig et al. 1988). An economical process for removal of glucosinolates and aglucons from crambe meal or low or no glucosinolate crambe germplasm would enhance the potential for use of crambe meal in nonruminant animal feeds. There is no assurance that breeding programs will develop low glucosinolate crambe cultivars. In fact, there are arguments for retaining glucosinolate levels in crambe, since they appear to play a role in crambe's insect resistance (Bell and Charlwood 1980). Research on crambe meal needs to continue with simultaneous basic and applied studies. For example, a series of trials conducted according to FDA guidelines to address the current restrictions for use of crambe meal are needed, wherein the first objective would be to increase the allowable use level or to remove the current limitation on use of crambe meal in feedlot beef cattle. A second objective would be to follow with clearances for crambe meal use in other phases of beef production. Research sponsored and encouraged by HEADE, and recent results obtained at NDSU, provides strong support for these objectives.


Although crambe has been grown successfully on a larger scale in the 1990s than in the past, further genetic improvement is required to insure future advancement and competitiveness with crops that produce similar end products. With this in mind, a vigorous crambe breeding effort is being continued (Table 10).

Past Breeding Efforts

Lessman (1990) reviewed the early breeding work with the crop at Purdue University. This research culminated with the release of the three cultivars, 'Prophet', 'Indy', and 'Meyer', and the accumulation of valuable information concerning the inheritance of agronomic and quality traits. Lessman suggested that improvement in crambe may be obtained by crossing among diverse germplasm, followed by selection, in addition to selection within and among existing germplasm.

Campbell et al. (1986a, b) developed and released the cultivars, 'BelAnn' and 'BelEnzian', and the lines C-22, C-29, and C-37, by introgressing genetic material from wild populations into Indy. The five releases performed as good as or better than 'Prophet', 'Indy', and 'Meyer' in several locations.

Lessman continued his breeding effort at New Mexico State University during the 1980s and developed a group of elite lines that approached his earlier releases in performance. With Lessman's retirement in 1991, HEADE arranged to establish a crambe breeding program at North Dakota State University. Crambe germplasm gathered for the NDSU program included previously released cultivars, 103 accessions from the world collection maintained at the North Central Plant Introduction Station at Ames, Iowa, and breeding material from Lessman's Purdue and New Mexico State University programs.

Current Objectives

The objectives of the NDSU crambe breeding program include: (1) increase seed yield; (2) increase oil content of the seed to a level near that of rapeseed; (3) lower glucosinolate content to acceptable levels or eliminate them altogether; (4) increase erucic acid content of the oil to its maximum level; (5) and develop cultivars that are resistant/tolerant to potentially harmful diseases, Alternaria and Sclerotinia, and insects, such as the diamond back moth. Other characteristics being considered include resistance to lodging and seed shatter, and a short seed dormancy period.

Breeding Approaches

These objectives are being approached in two ways: (a) evaluation of existing germplasm; and (b) selection among and within breeding populations developed through hybridization among existing germplasm and subsequent selfing. A bulk-pedigree method is being used as inbred lines are originally derived from F2 plants and seed is bulked in the succeeding generations. By using a two-generation greenhouse season and a winter nursery, F2:5 lines are available for evaluation two years after the crosses are made. Preliminary yield evaluations are being initiated in the F2:6 generation.

Recent Progress

Performance evaluations conducted at numerous locations in North Dakota in the years 1992-94 have indicated that many breeding lines have the potential to perform better than the currently grown cultivars, 'Meyer', 'BelAnn', and 'BelEnzian', in all important characteristics (Hanzel et al. 1993; Hanzel and Montgomery 1994, 1995). However, no one breeding line contains all traits expressed at the desired levels. Breeding efforts are continuing to combine all desirable traits. Oil content has still averaged well below the desired level, and, of thousands of lines evaluated in the three-year period, only several have possessed glucosinolate levels that approach acceptable levels. Non-conventional breeding techniques are being considered to modify the expression of these traits.


Crambe has found a home in the Northern Plains where it has been successfully grown, processed, and marketed on a commercial scale since 1990. It's success was fostered by the sharing of risk among producers and processors, each with visions of the potential benefits of commercializing this alternative crop. Ecologically, crambe offers a unique opportunity for farmers to diversify their crop rotations. Crambe shares few pests with small grains and exhibits considerably more field tolerance to diseases common among other broadleaf crops, such as sunflower and dry beans. Crambe also exhibits tolerance to a fairly wide range of insects and is not generally eaten by birds, which are often a problem near water in the Northern Plains, a major North American flyway.

Economically, crambe has also been advantageous. Investment in more equipment is not required, since crambe can be grown with equipment traditionally used to produce small grains. It is produced with a minimum of expense, and requires few pesticides. Being an industrial oilseed, crambe's price is somewhat independent of the traditional edible oilseed complex, thus offering farmers additional marketing alternatives. And, because of it's relatively low test weight, crambe will tend to be processed locally. In short, crambe has been a welcome addition to the repertoire of crops grown in the Northern Plains.

Crambe oil's major use in the well-defined erucamide market is welcome, but innovative research to develop additional markets is needed to sustain and expand domestic production of crambe and crambe oil. Perhaps the HEADE team's greatest disappointment was its inability to garner sufficient funding to pursue additional research and development in potential new product areas. The proprietary nature of some of the product development research sponsored by HEADE makes it inappropriate to discuss in this open forum. Also, though not discussed in this paper, HEADE sponsored some significant oilseed processing research, which aided the commercialization of crambe and has been or will be published elsewhere.


*The use of brand or trade names may be necessary to report factually on available data. The USDA neither guarantees nor warrants the standard of the product, and use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable. All programs and services of the USDA are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, age, marital status, or handicap.
Table 1. High Erucic Acid Development Effort (HEADE) participants and contributions by discipline or expertise. USDA = U.S. Department of Agriculture. CSREES = Cooperative State Research, Education, and Extension Service. OIM = Office of Industrial Materials. ARS =Agricultural Research Service. NCAUR = National Center for Agricultural Utilization Research.

Institutional partner Contributions by discipline and acquired knowledge
USDA, CSREES, OIM Management, oversight, budgeting
USDA, ARS, NCAUR Management, chemistry, oil & meal processing, markets
University of Georgia Rapeseed: breeding, production sciences
University of Idaho Rapeseed: breeding, plant & animal sciences, crop production, economics
University Illinois Animal science, marketing
Iowa State University Crambe: plant science, processing, economics
Kansas Board of Agriculture Marketing, economics, management skills
Kansas State University Plant & animal science, processing
University of Missouri Management, plant & animal science, economics
University of Nebraska Plant & animal science, process engineering
New Mexico State University Crambe: breeding, plant science, crop production
North Dakota State University Crambe: breeding, plant and animal science, chemistry, marketing, extension service to growers

Table 2. High Erucic Acid Development Effort (HEADE) management structure.

Organizational unit Unit functions and responsibilities
Management Committeez Provide leadership, establish budget, set priorities, allocate resources, coordinate research, promote communication, review progress, report results
Production Research and advice for: seed increase/certification, agronomy, plant diseases, insect & weed control, and breeding; commercial seed production assistance
Processing & Co-products Research and advice for: seed preparation and oil extraction, oil and meal quality, meal feeding studies
Marketing & Economics Market development, product development, economics, private sector interactions
zChairperson and Coordinator elected for 'day-to-day' management, conducting meetings, coordinating activities, appointing subcommittees, and handling communications and paper work.

Table 3. Commercial crambe production statistics from North Dakota, 1990-1995.

Statistic 1990 1991 1992 1993 1994 1995
Hectares 955 1,812 8,532 22,469 17,790 538
Net yield (kg ha-1) 1,456 1,499 1,275 1,132 1,456z 1,568z
Net crush (tonnes) 1,057 2,340 11,128 21,948 nay 0
Foreign matterx (%) 14.8 10.3 9.9 13.8 na na
Moisturex (%) 8.5 9.0 9.6 10.4 na na
Test weightx (kg m3) 327 341 332 324 na na
Oil yield (%) 28.5 32.2 31.1 32.3 na --w
Meal yieldv (%) 67.6 66.4 61.5 56.8 na --
Seed oil (%) 29.1 32.7 33.1 31.9 na --
Meal moisture (%) 8.8 9.5 8.3 9.6 na --
Meal protein (%) 32.1 30.4 30.5 30.5 na --
Meal fiber (%) 20.3 19.4 21.4 19.9 na --
Erucic acid (%) 57.2 57.6 57.1 55.3 na --
yNot available.
xNorth Dakota Grain Inspection Service (NDGIS). Test wt. mean=331 kg m-3 (25.7 lb bu-1).
wNot determined.
vCrop was partially dehulled before crushing beginning in 1992.

Table 4. Crambe meal beef feeding studies promoted by the High Erucic Acid Development Effort (HEADE). UNE = University of Nebraska-Lincoln. NDSU = North Dakota State University. WS = whole seed meal. DHS = partially dehulled seed meal. Source of crambe meal: National Sun Industries, Inc., Enderlin, North Dakota.

Year Study Location
1990-91: Commercial feedlot study Foxley Cattle Co. with UNE
1991-92: Feedlot study with WS NDSU, Carrington, ND
1992: Pilot study, lactating cows NDSU, Carrington, ND
1992-93 Feedlot study with DHS NDSU, Carrington, ND
1993: Digestion study (high forage) NDSU, Fargo, ND
1993-94: Creep feed, beef calves NDSU, Carrington, ND

Table 5. Major nutrients in defatted crambe meals.z

Content (% DM)
Defatted seed meal Protein Crude fiber Crude fat Acid deterg. fiber Ash N-free extract Glucosinolates (µmol g-1)
Whole seed 27.7 22.0 na na 7.7 40.0 45-70
Partially dehulled 34.6 nay 0.8 34.7 8.4 na 56.0
Totally dehulled 49.5 6.5 na 7.5 9.9 35.5 80-100
zSource: Anderson et al. 1993a; Kirk et al. 1966; Liu et al. 1994a, b; Mustakas et al. 1968; Baker et al. 1977; Carlson and Tookey 1983.
yNot available.

Table 6. Minerals in crambe meal and soybean meal (DM Basis).

Mineral Crambe mealz Soybean mealy
Calcium (%) 1.26 0.33
Phosphorus (%) 0.88 0.71
Potassium (%) -- 2.14
Sulfur (%) 1.26 0.47
Chloride (%) 0.70 --
Magnesium (%) 0.51 0.30
Sodium (%) 0.04 0.03
Iron (ppm) 110 142
Boron (ppm) 67 --
Zinc (ppm) 44 61
Manganese (ppm) 43 32
Copper (ppm) 15 30
Cobalt (ppm) 1.35 0.10
Selenium (ppm) 1.07 0.14
zNational Sun Industries, Inc.
yNational Research Council, Nutrient Requirements of Beef Cattle (NRC 1984).

Table 7. Amino acids in crambe meal and soybean meal (DM basis).

Content (g/16g N) DM basis
Amino acid Crambe mealz Soybean mealy
Alanine 3.8-4.2 4.29
Arginine 5.7-7.3 7.27
Aspartic acid 6.0-7.6 11.78
Cystine 2.6-2.8 0.93
Glutamic acid 14.2-17.0 18.63
Glycine 4.7-5.3 4.30
Histidine 2.2-2.7 2.55
Isoleucine 3.7-4.1 4.58
Leucine 5.9-6.8 7.75
Lysine 4.9-5.7 6.43
Methionine 1.6-1.9 1.13
Phenylalanine 3.4-4.0 5.01
Proline 5.5-6.2 -.-
Serine 3.5-4.1 5.45
Threonine 3.1-4.6 3.93
Tyrosine 2.5-3.0 3.75
Valine 4.5-5.6 4.58
zSource: National Sun Industries, Inc., Enderlin, North Dakota.
yCavins et al. 1972.

Table 8. Glucosinolates in crambe meal and in high (HGRS) and low (LGRS) glucosinolate rapeseed meals.

Glucosinolate content (µmol g-1)
Common name Chemical name Crambe mealz HGRS mealy LGRS mealx
Progoitrinw 2-Hydroxy-3-butenyl 56.3 22.5 5.2
Gluconapin 3-Butenyl 0.3 31.2 4.5
Sinigrin Allyl or 2-Propenyl 0.4 -- --
Glucobrassicanapin 4-Pentenyl 0.8 22.9 3.9
Gluconapoleiferin 2-Hydroxy-4-pentenyl 0.4 3.8 1.3
Neoglucobrassicin 1-Methoxy-3-indolylmethyl -- 12.3 12.5
Total glucosinolates 59.4 93.1 27.4
zPartially dehulled 1992 crambe meal. Source: National Sun Industries, Enderlin, ND. Analysis by POS Pilot Plant, 118 Veterinary Road, Saskatoon, SK, Canada.
yB. campestris, cultivar 'Torch' (Bell 1984).
xB. campestris, cultivar 'Candle' (Bell 1984).
wSterioisomers: epi-progoitrin in crambe and progoitrin in rapeseed (Daxenbichler et al. 1968.)

Table 9. Performance of steers fed partially dehulled crambe meal (CM).z,y

Crambe meal dietsx
Statistic Control 100 SBw 33 CM 67 CM 100 CM Ureav SE
Initial wt. (kg) 294 294 294 293 294 2.44
Final wt. (kg) 520 540 538 520 529 4.15
Avg. days on feed 162 161 160 160 159 1.32
Avg. daily gain (kg) 1.40 1.53 1.52 1.42 1.48 0.09
Feed/gain (kg/kg) 2.97 2.84 2.91 3.06 2.95 0.57
DM intake (kg/d) 9.19 9.55 9.71 9.54 9.61 0.19
zGrowing (84-d) and finishing (96-d) trials (Anderson et al. 1993a, b).
y1992 Crambe meal. Source: National Sun Industries, Inc., Enderlin, ND.
xPercent of supplemental protein from crambe meal replacing supplemental protein from soybean meal.
w100% of supplemental protein from soybean meal.
vUrea diet supplemental protein provided by crambe meal (50%), soybean meal (23%), and urea (27%).

Table 10. Crambe breeding programs.

Breeder/ Institution Era Results
K.J. Lessman Purdue Univ. 1960s & 1970s Prophet, Indy, & Meyer cultivars
K.J. Lessman New Mexico State Univ. 1980s Elite lines (possible male sterility)
T.A. Campbell USDA, Beltsville, MD 1980s BelAnn & BelEnzian cultivars
J.J. Hanzel North Dakota State Univ. 1990s Elite lines (possibly lower glucosinolates)

Last update June 11, 1997 aw