The straws are longer, which is why they cannot be fertilized with nitrogen. Unlike other spelt varieties, it was never crossed with wheat. It was also not bred for dough stability, which is why it must be baked in a special way, for example, using a water roux. The glutenin-to-gliadin ratio is different, resulting in a highly extensible but weaker gluten network.
It is really different from usual spelt, which was crossed with wheat and has shorter straws.
Edit: maybe this is interesting to some so I'll write a short paragraph about older varieties. There is also Einkorn and Emmer. Einkorn is considered the ultimate ancestor of all modern wheat varieties. It has been grown 10k years ago and is diploid with only two chromosome sets. Then there is Emmer, which is also ancient and appeared shortly after Einkorn. It is tetraploid and yields two corns per spikelet. If you want to eat like an Egyptian Pharao you can eat bread made out of Emmer ;-)
Rye is entirely different. It is very hardy and frost resistant and can't be baked without sourdough because of the amylase.
It is really different from usual spelt, which was crossed with wheat and has shorter straws.
Edit: maybe this is interesting to some so I'll write a short paragraph about older varieties. There is also Einkorn and Emmer. Einkorn is considered the ultimate ancestor of all modern wheat varieties. It has been grown 10k years ago and is diploid with only two chromosome sets. Then there is Emmer, which is also ancient and appeared shortly after Einkorn. It is tetraploid and yields two corns per spikelet. If you want to eat like an Egyptian Pharao you can eat bread made out of Emmer ;-)
Rye is entirely different. It is very hardy and frost resistant and can't be baked without sourdough because of the amylase.