Novel Food Information - Glabrous canary seed (Phalaris canariensis L.)

Health Canada has notified the Canary Seed Development Commission of Saskatchewan (CDCS) that it has no objection to the sale of glabrous (hairless) hull varieties of brown and yellow coloured canary seed (Phalaris canariensis L.) as cereal grain for human consumption. Dehulled glabrous brown and yellow coloured canary seed (also known as groats) is intended to be used either as whole groat, whole meal, whole grain flour or the milled products as ingredients in bakery, cereal, pasta, snack and nutritional bar market. The grain could also be used as a low fat substitute for sesame seed (a priority allergen) in breads, or snack foods, or in combination with other seeds as toppings or ingredients. Due to the absence of gluten-like proteins, canary seed could also be used as a gluten-free grain similar to teff, sorghum, amaranth, and buckwheat but it is inconclusive on whether canary seed could pose a risk for wheat allergic individuals. Therefore, the label of canary seed and foods containing canary seed as an ingredient would be required to carry a statement such as "May not be suitable for people with wheat allergy". As canary seed itself is not a priority allergen, it is not subject to the enhanced allergen labelling regulations and therefore should not be placed in a separate "contains" statement on the product label. However, as per general food labelling regulations, canary seed would need to appear in the ingredient list of prepackaged multi-ingredients foods containing canary seed.

The Department has reviewed the information submitted by the Canary seed Development Commission of Saskatchewan (CDCS), on behalf of producers of canary seed in Canada and conducted a comprehensive safety assessment of the acceptability of use of these varieties of glabrous hull canary seeds as cereal grain in the Canadian food supply.

Background

The following provides a summary of the notification from CDCS, and the evaluation by Health Canada and contains no confidential business information.

1. Introduction

Glabrous canary seeds suitable for human consumption refer to the dehulled glabrous brown and yellow coloured canary seed/groats which is comprised of carbohydrates, protein, crude fat and inorganic material (ash). Canary seed belongs to the family Poaceae (alternate name Gramineae) and the sub-family, Pooideae, like common cereal crops such as wheat, barley, rye and oat. The growth and development of annual canary seed is quite similar to wheat (Triticum aestivum L.) or oat (Avena sativa L.). The American Association of Cereal Chemistry International (formerly the American Association of Cereal Chemists) lists canary seed as a true cereal as it comes from the seed heads of a member of the Poaceae family (Jones & Engleson, 2010).

2. Description of the Novel Food

Canary seed is primarily used in the birdfeed market as a major component in feed mixtures for pet and wild birds. The commercial cultivars of annual canary seeds for the bird feed market are brown coloured seeds and can be either pubescent, (contain small silicified hairs (trichomes or spicules) covering the hull surface) or glabrous (no spicules). The glabrous hulled yellow and brown canary seed varieties in question were developed from the hairy (pubescent) brown canary seed cultivar through mutagenesis/conventional breeding to exhibit two traits (glabrous hulls and yellow seed colour). Neither pubescent nor glabrous canary seed has a history of safe food use. Therefore, canary seed is considered a novel food under the following part of the definition of novel foods: "(a) a substance, including a microorganism that does not have a history of safe use as a food". The Food Directorate has a legislated responsibility for pre-market assessment of novel foods and novel food ingredients as detailed in Division 28 of Part B of the Food and Drug Regulations (Novel Foods).

The safety assessment performed by Food Directorate evaluators was conducted according to Health Canada's Guidelines for the Safety Assessment of Novel Foods. The assessment considered: the development of glabrous canary seed; potential manufacturing and processing methods; its intended use and the directions for preparation; its history of use; incidental intake of heavy metals and mycotoxins; nutritional and anti-nutrient composition; microbiological and toxicological information; presence of potential allergens and estimation of its level of consumption by consumers.

3. Product Development

The glabrous varieties of canary seeds used in this submission were developed through mutagenesis from the pubescent cultivar Keet. The resultant mutant generations (M1, M2 and M3) were successively grown under field conditions, harvested and bulked. A single M3 glabrous panicle, possessing glabrous glumes and hull was identified from the M3 generation.

The brown glabrous cultivar of canary seeds were developed by growing the M4 generation glabrous plants and their M5 progeny under greenhouse conditions. CDC Maria, the glabrous brown cultivar, was selected based on agronomic field evaluation beginning in the M6 generation. CDC Maria is adapted to the traditional canary seed-growing region of Saskatchewan, the brown, dark brown and black soil zones.

For development of the yellow glabrous cultivars, the mutant populations (M4) were also screened and selected for pubescent yellow seed phenotype (CY184). Cross breeding of the two lines (CDC-Maria and CY184) yielded glabrous brown (CC9007) and glabrous yellow (CC9005) seeds. The yellow seeded hairless variety that is used in this novel food submission was derived from cross breeding and selection of traits from CC9005 with CDC Maria and another pubescent hull cultivar, Cantate. Selection of the desired traits through successive generations (F) yielded the glabrous yellow seeds (C05041 & C05091).

Canary seeds will be processed using common cereal processing methods to produce whole meal flour, milled products or other forms (e.g. flakes).

4. Dietary Exposure

According to CDCS prototype formulation, substituting 20-25% of the grains/seeds in recipes generally produced acceptable products. The highest level of inclusion tested was 50%, in a standard gluten-free sugar cookie recipe where the ingredients are just sugar, canary seed flour and oil.

CDCS used the current consumption levels of whole grains and seeds by the Canadian population (data from the 2004 Canadian Community Health Survey, Cycle 2.2 (CCHS cycle 2.2)) and projections for the replacement of currently-used grains and seeds with canary seed ingredients (20-25%) in various food products to estimate the consumption levels of canary seed. CDCS calculated from the CCHS cycle 2.2 data, the mean, and upper and lower 95th percentile for all-users intakes, and percent consuming were performed for all grain, whole grain, refined grain and seed categories to demonstrate the profile of total grain consumption in Canada for different sub-populations. The daily dietary exposure using mean body weights for each age group based upon weighted and bootstrapped values was estimated from the CCHS cycle 2.2 study.

CDSC projected that whole canary seed (whole meal, whole grain flour/milled products) could replace 25% of all whole grain products and that whole canary seed groats could replace 25% of sesame seeds currently consumed (because sesame seeds are a priority allergen, it is expected that sesame seeds would be the most commonly replaced seeds). Based on CDCS calculations, the intake values for the entire population at the 95th percentile were 0.3 g/kg bw/d each for both whole grain and groats, for a total canary seed intake of 0.6 g/kg bw/d. The highest consuming population group was children 8 years old and under, whose 95th percentile consumption levels for whole grain and groats were 0.8 and 0.6 g/kg bw/d, respectively, for a combined intake of 1.4 g/kg bw/d.

5. Chemical Assessment

Empirical data for trace elements (i.e. arsenic, cadmium, lead and mercury) and mycotoxins (i.e. aflatoxin, total fumonisin, ochratoxin A, deoxynivalenol and zearalenone) in glabrous canary seed were used to estimate the potential concentrations of these substances in foods in which glabrous canary seed could be used as an ingredient. The estimated concentrations were compared to levels normally seen in these foods on the Canadian market. The levels of trace elements and mycotoxins reported in the glabrous canary seed itself were also compared to available Canadian data for a variety of flours including wheat and rice flour as well as Canadian data for a variety of unprocessed cereal grains, where available. Additional background occurrence data specifically for canary seed or other types of seeds was not available for comparison; therefore the potential exposure to trace elements and mycotoxins from continuous long-term consumption of glabrous canary seed were also evaluated and compared to overall background dietary exposure and to toxicological reference values (TRV), where available.

Overall, the addition of glabrous canary seed in the foods and at the proposed levels of use specified by the petitioner is not expected to increase background dietary exposure or contribute to a significant proportion of the TRV for the trace elements and mycotoxins for which data were provided.

Therefore, from a chemical safety perspective, glabrous canary seed is not expected to pose a safety concern to human health.

6. Microbiological Assessment

The petitioner provided information regarding the microbiological contamination (total plate counts, coliforms count, yeasts and moulds) at different stage of the manufacturing process for one lot of yellow and one lot of brown glabrous canary seeds. The results provided are consistent with what can generally be found in cereals (Canadian International Grain Institute (CIGI), 2006, International Commission on Microbiological Specifications for Foods (ICMSF), 2005). The microbiological risks associated with glabrous canary seeds would be similar to those observed in other cereals.

Health Canada has no further questions and has no objection to the commercialisation of glabrous, yellow and brown canary seeds with respect to microbiological safety.

7. Nutritional Assessment

Glabrous canary seeds were planted in a three-replicate randomised complete block design in two phases in two time frames in Saskatchewan at 3 different sites (Phase 1 in 1996-1998); and 5 different sites (Phase 2 in 2007 and 2008), respectively. In Phase 1, glabrous canary seed were grown alongside the parent pubescent canary seed and the Canada Western Red Spring (CWRS) hard wheat "Katepwa". Comparisons were also made with values of commonly consumed cereal grains to illustrate that the nutritional composition of the glabrous canary seeds were similar to other cereals with history of consumption in Canada.

For the compositional analysis, the CDCS provided the following: proximate composition (protein, carbohydrate, crude fat and ash), fatty acids, amino acids; carbohydrate fractions; vitamins, minerals and anti-nutrients (phytate, total phenolic content, condensed tannins, other phytochemicals, trypsin and α-amylase inhibitors). The analytes measured in the CDCS's study were similar to those listed for cereal in various Organisations for Economic Co-operation and Development (OECD) Consensus Document on Compositional Considerations for New Varieties OECD.

Glabrous and pubescent canary seeds were similar in proximate composition except for slightly lower crude fat and higher protein content in the glabrous canary seeds. With the exception of higher lysine content for the glabrous cultivar, the amino acid profiles were similar. The fatty acid profiles were also similar.

Similar to commonly consumed cereals, glabrous canary seed contains protein, carbohydrate (starch and dietary fibre), crude fat, vitamins and ash (mineral) as well as some anti-nutrients. As with other cereal grains starch is the major fraction of carbohydrates. The crude fat content in canary seed is higher than most cereal grains but lower than crude fat found in oil seeds such as soybean, flax and sesame. The major fatty acids reported for canary seed are also predominant in wheat and other grain products. The protein content, although higher than most cereals, was similar to the upper range of values reported for oats, and the total essential amino acids were similar to those of oats and maize. When the individual amino acids were considered, tryptophan, phenylalanine and cysteine contents of canary seeds were higher than other cereal grains reported in the literature. Similar to other cereal grains, the lysine content was low.

The levels of minerals and vitamins present in the glabrous canary seed were comparable to values found in literature for a number of wheat varieties and other commonly eaten cereals.

For the anti-nutrients, the total phenols, α-amylase inhibitor and trypsin inhibitor were similar to other common cereals. Condensed tannins were not detected in any varieties. The phytate content in canary seeds was higher (14.1-23.2 mg/g) than the CWRS common wheat, "Katepwa" (10.7 mg/g) used in the CDCS study. However, the phytate present in the glabrous canary seed is in the range of other commonly consumed legumes, seeds, nuts and cereals.

Further data provided on the nutrient composition of proposed processed canary seed groats, other prototype food products including wheat containing recipes substituted with canary seeds in recipes (prototype), did not raise any nutritional concerns.

As an additional safety measure, the petitioner provided studies to support nutrient bioavailability of canary seed. The information provided included an in vitro protein digestibility study, rodent studies (phase 1 and 2) and two swine studies. While the rodent studies were designed primarily as toxicological studies, growth was shown to be acceptable. The results from the in vitro protein digestibility study suggest that the proteins in canary seed are digestible.

Results from the swine studies showed that canary seeds can be used for swine feed and that the dry matter digestibility, crude protein digestibility, digestible energy for canary seed cultivars were within the range reported for traditional and secondary cereal grains use as swine feed. As well, consumption of canary seeds at the levels used in the study had no adverse effect on the growth of swine. Swine are considered to have similar digestive systems to humans and are also suggested as a model for protein digestibility study for humans (FAO, 2011). The results presented support the proposal that canary seed is nutritionally safe.

8. Toxicological Assessment

Traditional pubescent canary seed has a limited history of use as a human food. The toxicological assessment of glabrous canary seed took into consideration two 90-day feeding studies in rats, two nutritional studies in pigs, and the composition of canary seed in terms of proximates and antinutrients. This information was considered sufficient to assess this novel food.

In a 90-day study, groups of rats received either a control diet (0% canary seed) or a diet containing 2.5, 5.0, or 10.0% dehulled glabrous yellow canary seed groats, or 10% dehulled glabrous brown canary seed groats. There were no adverse treatment-related differences among groups. The no observed adverse effect level (NOAEL) for dehulled glabrous canary seed, both brown and yellow, was considered to be approximately 5.2 g/kg bw/day (the highest dose tested).

In another 90-day study, four groups of rats received diets containing 50% by weight of either: Canada Western Red Spring (CWRS) wheat (controls), pubescent brown canary seed groats with hulls, glabrous brown canary seed groats with hulls, or glabrous brown canary seed groats without hulls. There were no treatment-related adverse effects. The overall NOAEL of glabrous brown canary seeds (both sexes, hulled and dehulled seeds) was approximately 38 g/kg bw/day. This value is approximately27 times higher than the estimated 95th percentile upper CI intake value for children under 8 years old (1.4 g/kg bw/day).

No information was provided on canary seed's potential genotoxicity or carcinogenicity. However, pathological assessments of acceptable subchronic studies (there are no chronic studies) gave no indication of neoplastic changes. The composition of canary seed is comparable to those of other cereals and it belongs to the same subfamily (Subfamily Pooidiae of the Family Poaceae alternate name Gramineae) as wheat, rye, barley, and oats, so there is no reason to anticipate that it would be genotoxic or carcinogenic.

No studies were conducted on canary seed's potential reproductive or developmental toxicity. However, comprehensive chemical and compositional studies were conducted on canary seed. There were no unidentified major peaks in the ultra-performance liquid chromatography (UPLC) analyses carried out to identify possibly toxic alkaloids and amines. In the event that a currently unknown but harmful alkaloid, amine, or other substance were present, it would likely exist in very low quantities, as the UPLC analyses did not indicate the presence of identifiable levels of any unknown substance. No other commonly consumed grain or grass is known to affect reproductive performance or to be a teratogen. There was also no evidence from two 90-day studies of a harmful effect on the reproductive system by canary seed based on organ weights, gross observations, or histopathology.

The composition of canary seed (pubescent or glabrous) is comparable to that of other commonly consumed grains in terms of nutrients and anti-nutrients. The levels of anti-nutrients in canary seed were not considered to be of toxicological concern. The predominant alkaloid was tyramine, to which exposure would be below a level of toxicological concern based on a conservatively estimated intake of canary seed.

The data provided by the petitioner support the safety of canary seed in the human diet at estimated levels of consumption. Therefore, from a toxicological perspective, Health Canada does not object to the use of canary seed for the purposes proposed by the petitioner.

9. Allergenicity Considerations

Canary seed belongs to the same subfamily as wheat, rye, barley, and oats (Pooideae). Celiac-related gluten is primarily found in the cereals from the tribe Triticeae (wheat, rye and barley). Mass spectrometry (MS) and bioinformatic analysis of canary seed proteins suggests a high homology with cereals from the tribe Aveneae, which includes oats and also canary seed. This analysis also found that canary seed proteins had some homology to the proteins found in rice, corn, carrot, tomato, radish, beet and chickpea.

Western blot analysis of three canary seed cultivars using polyclonal rabbit IgG antibodies raised against wheat gluten showed no binding to gluten-like proteins in canary seed in all three seed cultivars. Negative responses were also obtained with canary seed immunoblots exposed to two negative controls, rabbit anti-β-lactoglobulin IgG antibodies and rabbit anti-sesame IgG antibodies.

Three canary seed cultivars were tested with commercial ELISA (enzyme-linked immunosorbant assay) kits for gluten, soy, peanuts, tree nuts (almond, hazelnut, walnut), sesame and mustard. None of the ELISA based detection kits had any reactivity to the canary seeds. This result shows that the canary seed does not have epitopes that react with any of the antibodies from the kits. However, with the exception of gluten test kits, the kits use polyclonal antibodies, which react to an entire spectrum of proteins in the food and not necessarily all of the allergenic proteins. Consequently, the results were suggestive but not conclusive that people with those allergies would not react to canary seeds.

Based on the negative results from the gluten ELISA coupled with the mass spectrometry results, indicating a homology with oat protein, it was concluded that canary seed does not contain gluten type proteins from wheat, rye, or barley. With no contamination (< 20 ppm) by gluten sources from wheat, rye or barley, canary seed is not considered to pose a risk to people with celiac disease.

A small number (2) articles reported on canary grass pollen allergy. No reports of allergy because of canary seed ingestion were found in the literature. This finding was expected due to the limited history of food use of canary seed.

Protein extracts from three canary seed cultivars were immunoblotted with pooled sera from 10 wheat allergic individuals. The sera were assumed to contain IgE binding capacity to wheat allergens. The results showed IgE binding to the canary seed extract as well as similar responses in millet, quinoa, teff, sorghum and buckwheat. An exception was the presence of a band at about 15 kDa observed in canary seed and wheat but not observed in the other grains.

The petitioner was asked to provide additional details on the mass spectrometry and peptide sequence data regarding the 15 kDa protein. The additional data that was provided was analysed by the Food Directorate, and it was determined that these peptides could be matched to peptides found in wheat. This suggested the possibility that wheat allergic individuals may react to proteins present in canary seed.

The data provided by the petitioner support the conclusion that canary seed does not contain gluten like-proteins but it is unclear whether canary seed poses an allergenic risk for wheat allergic individuals.

Health Canada considers that canary seed does not present a health risk to persons with celiac disease. However, the data presented cannot exclude the possibility that canary seed may not be suitable for individuals with wheat allergy. The CDCS is invited to provide a rationale to the Food Directorate for removing the allergy statement in the future, if/when sufficient evidence is collected to support it.

10. Labelling

Health Canada and the Canadian Food Inspection Agency (CFIA) share responsibilities in regard to labelling requirements for foods. Health Canada is responsible for health-based policy and standard setting under the Food and Drugs Act and Regulations, whereas CFIA is responsible for enforcement. CFIA also administers and enforces those aspects of the Food and Drugs Act and the Consumer Packaging and Labelling Act that ensure labelling is understandable, truthful and not misleading.

The data submitted on allergenicity supports that glabrous (brown and yellow) canary seeds are gluten-free, but is inconclusive on whether canary seed poses an allergenic risk for wheat sensitive or allergic individuals. Therefore, canary seed and foods containing canary seed are required to be labelled with information to communicate this potential risk to wheat allergic individuals, for example, "May not be suitable for consumers with wheat allergy." As canary seed itself is not a priority allergen, it is not subject to enhanced allergen labelling regulations and therefore should not be placed in a separate "contains" statement on the product label. As per general labelling requirements, canary seed would be required to appear in the list of ingredients on all prepackaged foods containing canary seeds.

Conclusion

Health Canada's review of the information presented in support of the use of brown and yellow glabrous canary seeds cultivars as cereal grain for human consumption concluded that there are no food safety concerns for the general population. To address the potential allergenic risk to wheat allergic individuals, canary seed products are required to carry a label statement about the possible risk. The CDCS is invited to provide a rationale to the Food Directorate for removing the allergy statement in the future, if/when sufficient evidence is collected to support it. It is the continuing responsibility of the manufacturers/sellers/distributors of canary seed to ensure that marketed products are in compliance with all applicable statutory and regulatory requirements.

This Novel Food Information document has been prepared to summarize the opinion regarding the subject product provided by the Food Directorate, Health Products and Food Branch, Health Canada.  This opinion is based upon the comprehensive review of information submitted by the petitioner according to the Guidelines for the Safety Assessment of Novel Foods.

For further information, please contact:

Novel Foods Section
Food Directorate
Health Products and Food Branch
Health Canada, PL2204A1
251 Sir Frederick Banting Driveway
Ottawa, Ontario K1A 0K9
novelfoods-alimentsnouveaux@hc-sc.gc.ca