1. While looking through PubMed “broccoli skin” search results, I read a 2018 study Comparative Study of Predominant Phytochemical Compounds and Proapoptotic Potential of Broccoli Sprouts and Florets that cautioned about erucic acid content in broccoli seeds:
“Our results revealed significantly higher total UFAs [unsaturated fatty acids] content in the sprouts in comparison to the florets, with very low amounts of harmful erucic [27] acid in sprouts (0.5%) and florets (2%), in comparison to the broccoli seeds (38% – data not shown).”
But its cited reference [27] Various concentrations of erucic acid in mustard oil and mustard said nothing about broccoli seeds.
Values were on a dry weight basis. Broccoli sprout age was four days.
2. Another search found this 2017 Erucic acid in feed and food position paper which stated:
“When in this Scientific Opinion the erucic acid content is reported as a percentage, this value refers to the percentage erucic acid in the total fatty acids on a weight basis.
A tolerable daily intake of 7 mg/kg body weight per day for erucic acid was established.”
See Beneficial dietary erucic acid? for important evidence available at the time that was intentionally overlooked and misinterpreted:
“Erucic acid is found to cause cardiac lipidosis in young animals, yet direct evidence of cardiac injury does not exist for young humans. Concerns about erucic acid safety and cardiotoxicity have been published in the press which are based on scientific reports in the 1970s that erucic acid disrupted oxidative phosphorylation and lead to accumulation of lipids in rat cardiac tissue.
Spanish toxic oil syndrome was a major concern, leading to questions about erucic acid cardiotoxicity. Yet it was found that not rapeseed oil per se, rather its carcinogen anilin-dye refined derivative caused cardiotoxicity.
Later, it was understood that reduced ATP production with erucic acid treatment was due to unapt isolation of rat cardiac mitochondria and lipid accumulation that was unique to rats that inherently harbour a low β-oxidative peroxisomal activity and tissue-specific metabolism of erucic acid. Similar structural or metabolic perturbations and tissue injuries were not encountered in monkeys, humans, and pigs.”
3. It referenced a 2002 Determination and Health Implication of the Erucic Acid Content of Broccoli Florets, Sprouts, and Seeds which stated:
“The erucic acid content of broccoli florets, sprouts, and seeds was found to be about 0.8, 320, and 12100 mg/100 g, respectively.”
Respective erucic acid percentages of total lipids on a fresh weight basis were provided as 0.4%, 1.1%, and 26.9%.
Florets, sprouts, and seeds had no relationships among them as they were different broccoli cultivars. Broccoli sprouts’ age wasn’t disclosed.
4. The 2002 study was updated in a 2004 Glucoraphanin and 4-Hydroxyglucobrassicin Contents in Seeds of 59 Cultivars of Broccoli, Raab, Kohlrabi, Radish, Cauliflower, Brussels Sprouts, Kale, and Cabbage which stated:
“All seed accessions contained substantial amounts of hexane-extractable lipids ranging from 21.8 to 42.0% (mean of 32.8%; 21.8-37.0 and 30.9% range and mean, respectively, for broccoli cultivars only), which were composed of 27.0-56.7% (mean of 46.7%;39.4-56.7 and 50.2% range and mean, respectively, for broccoli cultivars only) erucic acid.”
Seeds of the 2002 broccoli sprouts commercial product were measured at 31.4% lipids, with erucic acid content 51.6% of total lipids.
5. The 2018 study cited a 2013 Biochemical composition of broccoli seeds and sprouts at different stages of seedling development whose broccoli seed and sprout composition dry weights are in the below graphic:
- Broccoli seed lipid percentage of total carbohydrates plus crude fiber would be 9.36 g / (58.89 g + 15.47 g) = 12.6%.
- 3-day-old broccoli sprouts lipid percentage of total carbohydrates plus crude fiber would be 8.67 g / (54.4 g + 8.97 g) = 13.7%.
- No erucic acid contents were disclosed.
These four studies all required further work:
- 2002 couldn’t be bothered to use just one broccoli cultivar for its three measurements, or disclose broccoli sprout age.
- 2004 couldn’t resolve many of their findings with other studies.
- 2013 used weights to equate measurements, instead of relating germination stages back to a beginning number of seeds and their measurements.
- 2018 provided a bogus reference and an unsupported “broccoli seeds (38% – data not shown).” It claimed similarity with 2013, but a statistics package would say otherwise. It also didn’t comply with disclosing fatty acids weight as a percentage of broccoli sprouts weight.
Home sprouting has to deal with:
- unknown cultivar,
- unknown glucoraphanin and other glucosinolates contents,
- unknown sulforaphane and other healthy compounds, and now
- unknown erucic acid content.
Let’s reverse Microwave broccoli seeds to create sulforaphane calculations with 3-day-old broccoli sprouts have the optimal yields information to estimate an erucic acid content in one tablespoon of broccoli seeds. Measurements from Week 18 and Week 19 of Changing to a youthful phenotype with broccoli sprouts.
- Broccoli seed weight of one tablespoon 10.7 g.
- Lipids weight (10.7 g x 12.6% [2013 study]) = 1.35 g.
- Erucic acid weight in one tablespoon of broccoli seeds (1.35 g x 26.9% [2002 study]) = 0.36 g.
This 0.36 g erucic acid content would be lower than 2017 guidelines for my 70 kg weight (7 mg x 70) = 0.49 g.
Let’s reverse Estimating daily consumption of broccoli sprout compounds techniques to estimate an erucic acid content in my daily consumption of 3-day-old broccoli sprouts grown from two tablespoons of seeds:
- 131 g 3-day-old broccoli sprouts.
- Maximum lipids weight (131 g x 13.7% [2013 study]) = 17.9 g.
- Maximum erucic acid weight in 3-day-old broccoli sprouts (17.9 g x 1.1% [2002 study]) = 0.20 g.
Plug in your own numbers, but it looks like caution isn’t warranted for broccoli seed consumption. Consequences of a possible erucic acid content may be less than broccoli seeds’ healthy aspects.
One mitigation may be to start germination. Pick a point between broccoli seeds’ % of total fatty acids and ending 0.5% of 4-day-old sprouts [2018 study].
Not concerned with a daily estimate < .49 g erucic acid for broccoli seeds and sprouts. Back to a PubMed “broccoli skin” search.
See Politically correct about erucic acid and broccoli seeds for a follow up.