I've fed them candy boards with some pollen sub mixed in last February. They didn't complain. They actually consumed it good. Of course, I don't know if they got anything out of the pollen sub, or if they just ate it for it's sugar content, but either way they built up very well.
I have accustomed to feed protein in spring to bees and that is not a right way to do it.
I make dough with dough machine.
3 kg dry irradiated pollen
0,7 litre water to soften pollen over night
3 kg dry baker yeast
2 kg soya flour with fat or without
1 kg fructose ( or honey if you do not have AFB)
1 kg flour sugar
3 multivitamin pill crushed and diluted into water.
150 mg C- vitamin = Ascorbic acid powder
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10,7 kg total
Add two table spoon food oil if soya is fatfree.
28% pollen
If dough is too wet, add soya flour and balance the mixture with it.
Then I roll the paste between two dough paper to 5-8 mm plate and give it to the top bars of frame. During one week 2 super colony can eat 0,5-1 kg that dough. New born bees eat it very eargerly.
Near 20% pollen all colonies are not willing to eat dough. Keep total sugar content 50%. If yeast make bubbles add sugar.
Fructose take moisture from air.
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