The lead researcher of Eat oat sprouts for AVAs‘s second study made their PhD thesis freely available. It’s still informative 13 years later:

“The main objective of this research project was to obtain new knowledge on how to treat raw oat material of oat-based products in order to sustain or even increase levels of endogenous phenolic compounds, with emphasis on avenanthramides, in the final food product. Germination of oats proved to be a potential processing method for use on oats since it is relatively easy to perform, although time-consuming.”

Which of these may be better for you? 44.1 grams of 4-day-old hulless oat sprouts at the top:

Or 53.2 g of 3-day-old hulled oat sprouts at the bottom?

They both started from 20.0 g seeds, and germinated the same way up through three days. 20 grams was over 1,300 hulled oat seeds, and close to 700 hulless oat seeds.

3-day-old hulled oat sprouts taste better, have a higher germination rate, and supply more quantity of their nutrients by weight. Characteristics of hulls from the thesis:

“The hull constitutes on average approximately 25% of the total grain weight. Protein, oil, starch and water-soluble carbohydrate levels are overall relatively low.

A large number of bioactive phenolic compounds can be found, among them p-coumaric acid, ferulic acid, vanillic acid, tricin and avenanthramides. Hull constituents remain unaffected during germination.

Activity of β-glucanase increases during germination of oats, resulting in almost total degradation of β-glucan. Since β-glucan is known to have health beneficial effects in humans, degradation during germination is not desirable if oats are intended for use in food products rather than for brewing.”

I’m not going to deal with hulls. Humans can’t digest oat hulls anyway.

A case for 4-day-old hulless oat sprouts:

“Germination of oats can be a good method to sustain or increase avenanthramides and other potentially health beneficial phenolic compounds. Levels of avenanthramides can increase during germination, sometimes to a high degree.

There was no indication that the increase in avenanthramide content had reached a plateau for any cultivars at 120 h of germination, indicating that further increase could take place.

Total protein content in oats increases slightly during germination. Even though the increase is small, it is important, since essential amino acids lysine and tryptophan increase and therefore improve nutritional value.

Lipid content in oats decreases slightly during germination while content of free fatty acids increases, although there are differences between cultivars as well as between hulled and hulless cultivars.”