Soy Protein Isolate Reference Guide

 

Soy protein isolate (SPI) is made wholly from defatted soy meal. Soy protein isolate (SPI) is used as an ingredient in high-protein foods including dairy foods, nutritional supplements, meat systems, infant formulas, nutritional beverages, cream soups, sauces, and snacks.  It is also the source of protein in milk replacers. Due to its high protein content, soy protein isolate is highly suited for those people who have high protein needs due to, for example, growth (children), famine (acute needs), and chronic diseases (HIV/AIDS and tuberculosis). This product can also be fortified with various micronutrients and minerals.

 

1. Nutritional Value

Macronutrient and micronutrient data per 100 grams of uncooked SPI:

Nutrient

Amount per 100 grams

Unit

Moisture

5

g

Protein (N x 6.25) moisture-free basis

90

g

Ash

5

g

Fat (petroleum ether)

1

g

Fat   (acid hydrolysis)

4

g

Crude fiber

0.2

g

Total dietary fiber

-

g

Total carbohydrates

trace

g

Energy

380

Kcals

 

 

 

Vitamins

 

 

Vitamin A

0

IU

Vitamin C

0

mg

Thiamine

0.18

mg

Niacin

1.44

mg

Vitamin D

trace

IU

Vitamin E

trace

IU

Vitamin B6

trace

mg

Vitamin B12

trace

mg

Folic acid

 0.18

mg

Biotin

trace

mg

Pantothenic acid

0.06

mg

Riboflavin

0.1

mg

 

 

 

Minerals

 

 

Sodium

150 - 1,000

mg

Potassium

100 - 1000

mg

Phosphorus

900

mg

Calcium

50 - 200

mg

Magnesium

25

mg

Iron

11

mg

Zinc

2.5

mg

Iodine

na

ppm


2. Components

            100% soy protein isolate.

 

3. Specifications

Chemical and physical requirements are:

Item

Minimum

Maximum

Protein (N x 6.25), % As is 

90

 

Moisture, %

 

6

Fat, %,  (petroleum ether)

 

1

Crude Fiber, %

 

0.2

Ash, %

 

4.5

PDCAAS

0.90

 

Carbohydrates (by difference)

4

 

Material through a U.S. standard 100 screen

95

 

Standard plate count

 

10,000

Salmonella

Negative

E. Coli

Negative

 

The product is kosher and pareve.

 

4. Packaging

SPI is shipped in 50-lb, multi-wall poly-lined paper bags.  Smaller packages of 25-lb are also available.

 

5. Shelf Life

The minimum shelf life of soy protein isolate is one year.  Manufacturers report that adverse conditions, including elevated storage temperature and high humidity, do not seriously reduce the shelf life.  The low moisture (<10 percent) and low fat (<one percent) content of concentrate, as with the defatted soy meal from which soy protein isolate is made, ensure that this product can be stored for long periods of time even when storage conditions are less than favorable. 

           

The functional properties of the isolate are estimated to remain excellent for one year.  The development of product rancidity during storage does not normally occur.  The nutritional quality of the product is excellent for several years.  Storage below 75 degrees F and 60 percent relative humidity will promote longer shelf life.  Based on anecdotal reports from isolate manufacturers, it has been successfully used globally, for more than 30 years, in developing and developed countries for its functional and nutritional benefits.