Hi Krakowska,
Interesting question! Let me try to provide some pros and cons regarding the stuff.
The
Journal Of Lipid Research has recently published a most interesting article regarding
oxysterols also known as "oxidized cholesterol". The article in entitled, "
Oxidized Cholesterol In The Diet - A Source Of Oxidized Lipoproteins In Humans" and may be found here:
http://www.jlr.org/content/44/4/705.full
While milk powders contain all twenty-one standard amino acids (the building blocks of proteins), and are high in soluble vitamins and minerals, they also contain "
oxidized cholesterol" - the
worst type of cholesterol! Thus, the heated debate about NFDM goes on, even though most of the cholesterol in your body does not come from the food you eat, rather, it is manufactured by your own liver. Opponents yet cite the presence of
oxysterols along with
high carbohydrate and
high fat content. (By the way, fresh fruits and vegetables are rich in antioxidants - your best defense against oxidized cholesterol).
In 1984, three years before "defatted soy flour" was developed by PTI, Rytek Kutas (referring to non-fat dry milk) wrote on page 159 of his revised edition book, "
If you are going to use a non-fat dry milk for a binder, your local dairy is usually the only place you can buy it today. The milk has to be a very fine powder and not the granules used for making milk at home. Better still, it should have the consistency of corn starch."
Okay Krakowska, let`s look at Non Fat Dry Milk. It contains:
36% protein
52% carbohydrates (mostly lactose)
1.3% calcium
1.8% potassium
26-40% fat
5-7% ash (minerals)
Proponents point out that although NFDM does not quite have the binding power of soy protein, non-fat dry milk powder is half lactose (sugar) and is often used in making fermented type "dry-cured" sausages such as salami and pepperoni. Why? It is ideal in supplying essential sugar to the lactic acid producing bacteria
pediococcus acidilactici and
lactobacillus curvatus. Although it is 36% protein, it is also known for improving the taste of low-fat sausages.
On the other hand, soy protein is often used in sausage making as a binder (not to be confused as a filler). As comminuted meat and fat particles are covered with the fine powder (having the consistency of corn starch), soy protein prevents fats from amalgamating and its water-holding ability only increases the firmness of a meat product. The amount added should not exceed 2-1/2% as the flavor of sausage becomes altered, most people calling it "beany" tasting.
Soy protein concentrate is produced by immobilizing soy globulin proteins while allowing soluble carbohydrates to be leached from the defatted flakes along with whey and salts. With these removed, soy protein flour remains. Now, there is a lot of technical saddle-bum science going on to further create edible soy protein concentrate and it involves the removal of specific aqueous acids in something called the isoelectric zone of minimum protein solubility.
And no kidding... it is achieved by the use of... (ta da)... alcohol! Long story short, the consumer winds up with soy protein concentrate at about 70% protein and it binds 4 part of water. Very helpful stuff in the food world. However, it contains a few other additives, including ash and fiber. Don`t ask me why. Shucks, there`s even 1% oil in the stuff. Shucks pard, it also takes one ton of defatted soybean flour to make 1653 pounds of soy protein concentrate. The list of the uses for soy protein concentrate in every industry you can imagine today is as long as my list of excuses for avoiding my wife`s relatives!
In defence of soy protein, Stan Marianski has pointed out that it contains all three nutrients required for healthy nutrition - protein, carbohydrate, and fat - plus the benefits of vitamins and minerals, including calcium, folic acid, and iron. Soy is nearly nutritionally equivalent to meat! It`s oil is 61% polyunsaturated and 24% monounsaturated fat - comparable to the total unsaturated fat content of other vegetable oil. And ... it contains NO cholesterol.
For people who are lactose intolerant (me included), the development of soy protein concentrate and soy protein isolate are a Godsend and very much appreciated. Many of us don`t have a choice, but for those who do, I suggest trying both and weighing the facts listed above. Then make up your own mind.
Best Wishes,
Chuckwagon