This 2020 review explored sulforaphane stability and formation:
“Sulforaphane (SF) is beneficial to our health since it can reduce incidence of a number of tumors, induce cell cycle arrest and apoptosis in multiple experimental models. However, since neither SF nor myrosinase is thermostable, it is essential to increase stability of SF and/or enhance conversion of glucoraphanin (GRP) to SF by myrosinase to maximize SF therapeutic benefits.
- Since little or no water is needed for microwaving and stir-frying, and broccoli is not immersed in water during steaming, SF content in broccoli florets is higher in these processes compared to that in boiled florets.
- Thermostability of Brassicaceae myrosinase varies across different species and cultivars, as well as the plant organ. For example, myrosinase in broccoli florets are more thermosensitive compared to that in sprouts, likely due to the presence of a seed-specific myrosinase.
- GRP in cooked broccoli can be hydrolyzed by intestinal microbiota to SF, sulforaphane nitrile, and/or other isothiocyanates and nitriles, although the decomposition rate is very low. However, continuous feeding of rats or mice with broccoli increased myrosinase-like activities in colon and cecum contents.
Mild heating (40-60 °C) by microwave increased SF content in broccoli. High-power microwave heating with temperature control at 60 °C could retain higher bioavailability.
Continuous broccoli ingestion enhances myrosinase-like activity of gut microbiota. Regardless of differences in endogenous amounts of glucosinolates and myrosinase across multiple broccoli varieties, moderate microwaving ensures optimum SF availability.”
https://www.sciencedirect.com/science/article/abs/pii/S0308814620326339 “Approaches for enhancing the stability and formation of sulforaphane” (not freely available)
Several studies previously curated were referenced, including:
- Microwave broccoli seeds to create sulforaphane;
- Microwave broccoli to increase sulforaphane levels;
- Enhancing sulforaphane content.
Why wait around for approval or citation or social validation of research? When Study 2 showed microwaving increased sulforaphane and glucoraphanin content this time last year, I followed the evidence and acted accordingly.
Researchers who deny microwaving’s beneficial effects on broccoli compounds up to 60° C can publish contrary findings, or keep their biased opinions to themselves. See Increase broccoli compound amounts with thermosonication for further evidence.
Surface Your Real Self 
Rhonda Patrick asked Jed Fahey if you can increase the sulforaphane in Broccoli sprouts by freezing them and he said yes. So, I freeze my sprouts. The question now, which method is best? Or does any of it matter as long as we are getting the proper daily dose of 25 – 40mg per day.
Another question since I could not find the button, can people here share their experience with daily intake of SFN and what it has done for them. Even better, my PSA score went down in a month and a half (9.5 to 8.8)
I will be watching about every month.
Most notable, I have arthritis in both of my wrist and both were swollen from inflammation and very painful at times. After 1 month, the swelling and inflammation are just about gone. Anyon else?
Hi btonnecfs! How is your week coming along so far?
I don’t follow broccoli sprout experts. I interpret studies on my own, assisted cognitively by eating an estimated 65.5 grams of broccoli sprouts twice a day.
Sure, keep posting. I don’t ascribe significance to PSA readings since the PSA discoverer doesn’t.
Regarding arthritis, I stopped playing golf after age 61 due to arthritis in my left thumb. Haven’t regained full capability, but inflammation is noticeably better.
Hi, and thank you very much for all your articles and experiments.
Sorry if I have a question not directly related to this article; I searched a lot in the Internet for any answer but didn’t find it.
Is there any measurement of how much Sulforaphane is there/or can be formed in Broccoli florets (mature heads)? (I know it is originally Glucoraphanin/Myrosinase that is converted to Sulforaphane).
If you can guide me on any article here or elsewhere; thank you very much.
OK; I found this while continuing my search over Internet: https://pubmed.ncbi.nlm.nih.gov/16569031/
It states that Sulforaphane concentration in mature Broccoli can be from 44 to 171 mg/100 g dry weight.
So, it can be considered as an answer to my question; it’s just I don’t know how to convert this “dry weight” to “normal weight” (I mean the weight of Broccoli we all buy from groceries, not the scientific preparation).
Hi Jeff! Thanks for commenting.
The second study in Broccoli sprouts’ immune effects had comparisons of fresh and dry weights in ten types of sprouts. What do you think?
Thanks for the link. The measurements are for the sprouts, but I think those for mature broccoli won’t be much different.
From Figure 1, we can find that fresh weight is approximately 15 times dry weight (1400/90 for Nov 2018, and 900/60 for Jan 2019).
Thank you very much for your help and guidance.