Not All Whey Is Made the Same Way
by Syed Rasheeduddin Ahmed

Whey is the watery portion of milk remaining after milk coagulation and removal of the curd. Whey can be obtained by acid, heat, and rennet coagulation of milk. There are two types of whey:

1. Sweet Whey: Sweet whey is manufactured during making of rennet type hard cheese like cheddar or Swiss cheese.
2. Acid Whey: Acid whey (also known as sour whey) is obtained during making of acid type of cheese such as cottage cheese.

In addition to its liquid form, whey is also produced in the following solid forms:

1. Whey solids or powder: This is obtained by drying the liquid whey and used as milk replacement in bakery products, ice cream, dry mixes and beverages.
2. Whey Protein Concentrate: is the dry portion of whey obtained by the removal of sufficient non-protein constituents from whey so that the dry product contains not less than 25% protein.

Most of the whey used in different food products is obtained as sweet whey from rennet types of hard cheeses.

Whey is concentrated to obtain sweet/acid whey powder, condensed whey, Delactose powder as the primary products and protein, lactose as secondary products.

Composition of Whey
	Fluid Sweet Whey	Fluid Acid Whey	Dried Sweet Whey	Dried Acid Whey
Total Solid	6.35	6.5	96.5	96
Moisture	93.7	93.5	3.5	4
Fat	0.5	0.04	0.8	0.6
Protein	0.8	0.75	13.1	12.5
Lactose	4.85	4.9	75	67.4
Ash	.5	0.8	7.3	11.8
Lactic Acid	.05	0.4	0.2	4.2

(Source: Cheese and Fermented Milk Foods by Frank Kosikowski)

Fundamentals of Whey Making

The procedure of whey making is similar to cheese making until the curd is formed. It starts with propagating the mother cultures (cultures are actually microorganism such as bacteria) on media (media is food material providing protein, fat, carbohydrate and nutrients to bacterial cultures) and followed by bulk culture propagating on media. The bulk cultures are added to the milk and then rennet preparation is added to milk to form curd in case of sweet whey. The whey is separated and dried.

For acid whey, lactic acid mother cultures are grown on media and then bulk culture are propagated and added to skim milk to make cottage cheese (cottage cheese is also made with the use of rennet). Whey is separated after curd formation and dried as a powder.

Halal Status of Whey

The media and the type of rennet may influence the halal status of whey produced from them. The following are the requirements for us to be completely sure that the whey is halal:

1. Mother culture media has to be halal.
2. Bulk culture media has to be halal.
3. Microbial rennet preparation has to be used.
4. Dryers where liquid whey is dried to make whey solid or powder should not be used to dry animal based media and rennet whey to avoid contamination.

It is advised that we restrict ourselves to Only halal or kosher certified whey as shown by the halal or kosher symbols such as UD, KD, and COR. Non-halal or Kosher certified whey made even with non-animal based media and microbial rennet is not recommended because the cheese manufacturer can change the media and rennet source any time without notifying Muslim consumers.