Antinutritional factors in Oil Meals and its effects

Sr.

No.

Oilseed Antinutritional Factors

1 Groundnut goitrogenic factors, trypsin inhibitors,

aflatoxins

2 Soybean trypsin inhibitors, saponin, legtins

3 Cottonseed Gossypol, malvalic acid

4 Rapeseed goitrogenic factors, thioglucosides

5 Linseed cyanogens compounds

6 Sesame oxalates

7 Sal tannins

8 Mowrah tannins, sponins

9 Castor ricin, allergens, ricinin

OILSEED: Source of Oil and protein (Meal).

AIM: To get high quality oil with best possible yield and to obtain oil meal

of highest possible value.

Oil Meal: Rich source of proteins and is used for human consumption,

animal feed and as farm yard manure. Use is restricted due to toxic

substances or anti nutritional factors. Anti nutrients left in oils gets removed

during the various refining stages. Most of them are left in cake, making it

nonedible.

Sr.

No.

Antinutritional

Factors

Effect

1 Lectins Affinity for sugar molecules. Attaches with sugar

moieties of cell membrane and interfere with the

absorption of nutrients across the intestinal wall.

2 Trypsin Inhibitor Inhibits enzyme activities of chymotrypsin,

plasmin

3 Goitrogens Inhibits uptake of iodine leading the deficiency of

iodine in thyroid and eventually produces goiter.

4 Tannins 8 – 10% in Sal meal. Forms complex with proteins

and enzymes. Reacts with trypsin (digestive

enzyme), making it insoluble. If there is protein

deficiency in diet, it reacts with body protein and

retards growth. Detected by brown coloration of

peanut hull. Content increases towards maturity.

5 Gossypol Cottonseed kernel contains 1.3% gossypol. Affects

color and nutritional properties of oil and meal.

Amino group of lysine reacts with –CHO group of

gossypol, making lysine unavailable during

digestion. Toxic to monogastri animals but not for

ruminants unless large amount is taken.

6 Aflatoxins Produced by Aspergillus flavus group of fungi. 4

types of aftatoxins are produced B1, B2, G1, G2. B1

is most toxic. Target organ is liver (hepatic

troubles) but may affect pancreas, kidney and

heart.

7 Phytic Acid Rapeseed flour contains 5% phytic acid. Phytate is

responsible for reducing mineral bioavailability.

Zn binds phytic acid and protein and decreases

solubility. Also binds trypsin, pepsin etc forming

insoluble complexes. During protein hydrolysis

phytate forms peptide phytate complexs those are

insoluble decreases solubility and availability of

nitrogen. Phytate reduces rate of starch digestion.

8 Glucosinolates Nontoxic if completely digested. In presence of

myrosinase produces glucose and isothiocyante.

Isothiocyante have goitrogenic properties, which

enlarges thyroid.

9 Ricin Occurs at a level of 1.5% in castor meal.

Extremely toxic and affects capillary blood

circulation in various organs like liver, spleen and

bone marrow. Quantity in milligrams can cause

poisoning and could be lethal.

10 Allergens Is nothing but chlorogenic acid. Can cause

omitting, diarrhea and fever.

11 Saponins Have surface active properties (Surface tension of

1% solution is 28 dynes/cm). Irritant to mucosal

membrane leads to gradual destruction of cells.

12 Estrogens Found in soybean. Consists of three isoflavons at

2.6 % level. Exist primarily as glucosides. These

are growth inhibitors.

Protein Recovery from Oilseed

Safflower seed Dehulling Hulls

Kernels

Prepressing and Solvent Extraction Oil

Defatted Meal Grind and Sieve Flour

Aqueous isoelectric pH adjustment, Membrane Processing and Drying

Washing and Drying

Protein Isolates

Coconut

Shell Remove Shell Coconut water

Meat Clean and Grind

Heating and Pressing

Coconut Milk

Oil Filter and Centrifuge

Vacuum Drying

Residue (Protein Concentrate)

Isoelectric pH adustment

Protein Isolates

Peanut

Hull Remove Hull Kernel Prepress and Sol. Extn Oil

Meal

Grind and Extract with dil. Alkali (pH = 8) and Filter

Liquid Extract Insoluble Residue

Adjust pH = 4 and Centrifuge Wash, Filter and Dry

Whey Protein Isolate Recovery of Insol. Protein

Detoxification of Meal

Castor Meal

Castor Meal

Steam

heating

at 15 psi

Toxicity decreases

to 1/2000th

of

original

Moist cooking with

2% NaOH/ Ca(OH)2

and 10% HCHO

Toxins and

allergins are

destroyed

Salseed and MowrahMeal

SoyMeal

Salseed/

Mowrah Meal

Treat with

30% aq.

Acetone

Dry the residue

Treat with 0.1%

NaOH overnight and

filter

Dry the

residue

Soymeal

Soxhlet

extraction by

ethanol

Saponins are

removed by

extraction