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  acid in sprouts (0.5%) and florets (2%), in comparison to the broccoli seeds (38% – data not shown).”
But its cited reference  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.
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.