Question Summary:
Is it permissible to consume yeast?

Question Detail:

AsalaamuAlaykum, hope all is well In Shaa.  I had a question regarding yeast. I have seen a few places on other sites suggesting yeast may not be ok to eat.  Please could you clarify this as yeast is in many products like bread, buns,  etc? Also yeast extract, is that different to yeast and would that be halal?
 
May Allah bless everyone at AskImam for this service,  Ameen. 
 
 
Many thanks 

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh
Yeasts are unicellular fungi.  It is commonly found in soils and on plant surfaces and are especially abundant in sugary mediums such as flower nectar and fruits.  Due to its useful physiological properties, it is commonly used in bakery and for the fermentation of drinks.
 
There are many different forms of yeast available including different usages for yeast products. The ruling of yeast and yeast extracts will be based on the source of the yeast product. Hereunder are the rulings for the common forms of yeast:
 
1. Bakers Yeast - The role of bakers yeast in the baking industry is to leaven bread and related food products. This form of yeast converts the food/fermentable sugars present in dough into the gas carbon dioxide.
 
Bakers yeast is permissible to consume.
 
2. Brewers Yeast - This type of yeast is used in fermenting sugar in malt to produce alcohol and carbon dioxide in beer making. It is also grown on food crops to make nutritional supplements.
 
Brewers yeast sourced from plants and crops is permissible.
 
With regards to brewers yeast produced from alcohol, then in principle, if Tabdeel Mahiyyah (complete metamorphosis) occurs of the alcohol within the yeast, then it will be permissible for one to consume such a product. However, if Tabdeel Mahiyyah does not occur, then it will not be permissible to consume such a product due to the presence of alcohol. There is currently difference of opinion whether Tabdeel Mahiyyah does occur or not among scholars.
 
We advise the Muslim Public to abstain from this form of yeast as we are still conducting research on the matter. We will inform the public on our findings once we have completed our research. We are currently consulting with a food technologist on the matter.
 
3. Torula Yeast - Torula Yeast grows on sulfite waste and sulfite liquors. It is also grown on sugar cane.
 
Torula yeast is impermissible to consume if it is produced from pure wine. However torula yeast product from sugar cane is permissible provided the yeast does not intoxicate and is not used for the purposes of frivolity and jest.
 
4. Pathogenic Yeasts – Certain types of pathogenic yeasts can cause medical harm to human beings. They are the species primarily responsible for cryptococcosis, a fungal disease which is estimated to have caused the deaths of approximately 600.000 people annually.
 
It is impermissible to consume yeasts which contain any proven medical harms.
 
And Allah Ta’āla Knows Best
Ismail Desai,
Darul Iftaa