STARCH IN ANIMAL STARCH IN ANIMAL FEEDFEED

Milica RadosavljevićMilica Radosavljević, Marija Milašinović, Zorica Pajić, , Marija Milašinović, Zorica Pajić, Milomir FilipovićMilomir Filipović

Maize Research Institute, Zemun Polje, S. Maize Research Institute, Zemun Polje, S. Bajića 1 Bajića 1

Belgrade-ZemunBelgrade-Zemun

OBJECTIVES

1. To summarise and perceptibly present our the most important results on investigations

on a starch role in animal feed and

2. To describe the utility value of grain of different ZP maize hybrids as a raw material in

its production.

INTRODUCTION:

•STARCH

•AMYLOSE

•AMYLOPECTIN

•STARCH STRUCTUTE

•CORN AS AN IMPORTANT SOURCE OF STARCH

STARCHSTARCH

THE SECOND LARGEST BIOMASS IN THE THE SECOND LARGEST BIOMASS IN THE WORLDWORLD

HOMOPOLYSACCHARIDE-GLUCOSE POLYMERHOMOPOLYSACCHARIDE-GLUCOSE POLYMER

MOLECULAR FORMULA: (CMOLECULAR FORMULA: (C66HH1010OO55)n)n

MAJOR COMPONENTS: AMYLOSE AND AMYLOPECTINMAJOR COMPONENTS: AMYLOSE AND AMYLOPECTIN

THE CHEMICAL STRUCTURE OF AMYLOSE

THE CHEMICAL STRUCTURE OF AMYLOPECTIN

CharacteristicsCharacteristics

Shape

Linkage

Molecular weight

Films

Gel formation

Colour with iodine

AmyloseAmylose

Essentially linear

-1,4 (some -1,6)

<0.5 million

Strong

Firm

Blue

AmylopectinAmylopectin

Branched

-1,4 and -1,6

50-500 million

Weak

Non-gelling to soft

Reddish brown

Light micrograph of corn starch granules

Electron scanning micrograph of corn starch Electron scanning micrograph of corn starch granulesgranules

Schematic representation of a starch granule (from Lineback 1984)

Schematic of the organization of a starch granule

(from J. Jane 2009)

CORN IS ONE OF THE MOST IMPORTANT

SOURCES OF STARCH

Animal feeding

The animal feed production is traditionally one of the greatest maize consumers. Not only in our country, but in many others, maize has suppressed almost all other cereals.

The most important and unique reason for this are its chemical properties and energy values.

As an essential component of the animal production, maize covers from 60 to 90% of energy necessary for functioning of the organism and for the maintenance of a body temperature.

Starch is in a principal carbohydrate and at the same time is an essential chemical constituent of maize grain. Its content averagely amounts to approximately 70%.

Composition of corn grainComposition of corn grain

ComponentComponent Average (%) Average (%) Typical range Typical range (%) (%)

StarchStarch

ProteinProtein

FatFat

Crude fiberCrude fiber

AshAsh

71.371.3

9.919.91

4.454.45

2.662.66

1.421.42

64 - 7864 - 78

8 - 148 - 14

3.1 - 5.73.1 - 5.7

1.8 - 3.51.8 - 3.5

1.1 - 3.91.1 - 3.9

Molecular marker assisted selection with the aim of getting a desirable genotype is now routinely applied in maize breeding programmes, which enables genetic control of a molecular starch structure, whereby its properties can be altered.

The performed studies show that the starch granule structure and interactions with other components within the endosperm, as well as, processing conditions influence starch digestibility.

However, in order to determine more detailed parameters of the starch structure that affect animal feed digestibility further systematic studies are necessary.

Considering directions of nutritive and technological observations, a special attention today should be paid to the development of inbreds and hybrids with specific traits and for special purposes.

Studies of the structure and unique properties of starch of speciality maize hybrids are aimed at hybrids such as waxy, high amylose, high lysine and high protein hybrids, which, again, due to being a raw material for the sustainable animal feed production get their own great and deserved importance

Approximate amylose and amylopectin content Approximate amylose and amylopectin content of common of common corn corn starchesstarches

Starch typeStarch type

Dent cornDent corn

Waxy cornWaxy corn

High-amylose cornHigh-amylose corn

AmyloseAmylose (%)(%)

2525

<1<1

55-70 (or higher)55-70 (or higher)

Amylopectin (%)Amylopectin (%)

7575

>99>99

45-30 (or lower)45-30 (or lower)

What makes corn starch so versatile as an What makes corn starch so versatile as an inexpensive raw material and ingredient of inexpensive raw material and ingredient of

many many feed and feed and food products?food products?

GELATINIZATIONGELATINIZATION

PASTINGPASTING

RETROGRADATIONRETROGRADATION

EFFECTS OF pH, SHARE, AND OTHER EFFECTS OF pH, SHARE, AND OTHER INGRADIENTSINGRADIENTS

Starch gelatinizationStarch gelatinization is the collapse is the collapse (disruption) of molecular order within (disruption) of molecular order within the starch granule manifested in the starch granule manifested in irreversible changes in properties such irreversible changes in properties such as granular swelling, native crystalline as granular swelling, native crystalline melting, loss of birefringence, and starch melting, loss of birefringence, and starch solubilization. solubilization.

The temperature at which starch begins The temperature at which starch begins to undergo these changes is referred as to undergo these changes is referred as the the gelatinization temperaturegelatinization temperature

Pasting is the phenomenon following in the dissolution of starch. It involves granular swelling, exudation of molecular components from the granule, and eventually, total disruption of the granules. Peak viscosity is the point at which, during heating in water, gelatinized starch reaches its maximum viscosity.

The effect of pH on starch gelatinization is an important consideration.

Shear can also have a dramatic impact on starch behaviour.

Because feed and food products are usually quite complex, the effect of other ingredients also has to be considered when evaluating starch functionality in terms of viscosity. Fats, sugars, proteins, and salts can all influence starch gelatinization, pasting and retrogradation.

MATERIAL AND METHODES-Nativne corn starches and grain of ZP corn

hybrids.

*Content of starch and other basic chemical constituents of corn grain (contents of protein, oil, crud fibre, ash)

*Chemical structure and functional properties of corn starch (contents of amylose, amylipectin and resistant starch, termochemical properties and viscosity)

*Maize starch and grain digestibility

-enzymatic hydrolysis by -amylase

-in vitro digestibility by Tolley and Terry

RESULT AND DISCUSSION

The chemical content and structure, functional properties and the digestibility of starch and maize grain, as a basic component in animal feed production, are described and discussed in this study.

The content of starch and other basic chemical constituents of the grain, i.e. the chemical

composition of maize grain

is its most important property, not only for food and feed, but also for the remaining of its uses. As a highly yielding carbohydrate plant, maize is very competitive in regard to other cereals in the animal feed production.

Hybrid Starch(%)

Proteins (%)

Oil(%)

Crude fibre (%)

Ash(%)

ZP 74b 70.7 9.6 4.8 2.4 1.3

ZP 243 70.2 10.6 5.7 2.0 1.5

ZP 300b 69.6 9.4 6.7 2.0 1.4

ZP 341 69.0 9.3 5.8 2.0 1.3

ZP 434 69.0 9.4 5.9 2.0 1.4

ZP 544 69.4 10.2 5.1 1.9 1.4

ZP 578 73.0 8.6 5.1 1.8 1.3

ZP 599 67.5 9.6 5.4 2.2 1.4

ZP 611k 68.2 12.7 4.8 2.3 1.5

ZP 633 72.8 9.9 5.1 2.8 1.4

ZP 677 70.2 9.6 5.1 2.1 1.4

ZP 684 70.5 8.8 4.8 2.1 1.4

ZP 704 70.6 9.6 5.0 2.1 1.4

ZP 704wx 71.2 9.4 4.7 2.3 1.4

ZP Rumenka 67.9 11.1 6.4 2.0 1.5

Average 70.0 9.9 5.4 2.1 1.4

Minimum 67.5 8.6 4.7 1.8 1.3

Maximum 73.0 12.7 6.7 2.8 1.5

SD 1.6 1.0 0.6 0.2 0.1

Chemical structure and functional properties of maize starch

Starch is one of the most important animals source of energy. The mechanisms of it degradation is very complex. The amylose to amylopectin ratio is important factor that affects the speed and the degree of starch degradation and its digestibility and consumption by animals.

In recent times resistant starches have been attracting the attention of many researches world-wide due to two reasons: potential positive effects on human health that can contribute to prevention of certain diseases, as well as, due to their functional properties.

HybridAmylose

(%)Amylopecti

n (%)Resistant starch (%)

ZP 74b 25.0 75,0 1.1

ZP 341 23.5 76,5 -

ZP 360 23.8 76,2 1.2

ZP 434 26.0 74,0 -

ZP 480 24.2 75.8 -

ZP 511 25.2 74.8 -

ZP 578 23.5 76.5 1.3

ZP 611k 23.2 76.8 1.5

ZP 633 24.0 76.0 -

ZP 677 23.9 76.1 -

ZP 680 21.7 78.3 -

ZP 684 23.3 76.7 -

ZP 704wx

1.0 99.0 0.6

ZP 735 24.8 75.2 -

ZP 737 24.0 76.0 -

ZP 750 23.7 76.3 -

ZP 808 24.0 76.0 1.6

ZP Rumenka

23.5 76.5 1.4

Average

22.7 77.3 1.2

Min 1.0 74.0 0.6

Max 26.0 99.0 1.6

Sd 7.0 5.5 0.3

Hybrid To (ºC) Tp (ºC) Tc (ºC) ΔH (J g-1)

ZP 74b 62.1 66.6 70.6 13.6

ZP 360 63.3 68.3 73.4 15.0

ZP 434 65.0 69.5 74.2 15.6

ZP 578 62.7 67.4 72.2 15.5

ZP 611k

64.5 67.9 71.6 14.2

ZP 633 63.3 67.8 71.9 15.2

ZP 684 63.2 67.7 71.7 14.5

ZP 704wx

63.7 68.8 74.7 18.1

ZP 808 62.9 67.4 71.6 14.3

ZP Rumenka

63.7 68.3 73.1 14.8

Average

63.4 68.0 72.5 15.1

Min 62.1 66.6 70.6 13.6

Max 65.0 69.5 74.7 18.1

Sd 0.84 0.81 1.3 1.2

The differential scanning calorimetry (DSC) method was applied to study the most important functional property, gelatinisation, and to determine thermo-chemical parameters of selected samples

0

50

100

150

200

250

0 100 200 300 400

Vis

co

sit

y (R

VU

)

Time (s)

ZP 704 wx ZP 434

The studies of gelatinisation and viscosity of maize starch are of enormous practical significance for the animal feed production, especially feed that is made by the application of a modern procedure of thermal processing of raw materials, for both the production process itself and for usability of nutrients in the animal organism.

Corn starch and grain digestibility

Not only the starch structure and its functional properties from the aspect of a starch role in the animal feed, but also its digestibility is also important.

0

20

40

60

80

100

3 24 48 72

Time (hr)

Dig

esti

bili

ty (

%)

Normal corn Waxy corn Du waxy corn

0

5

10

15

20

25

3 24 48 72

Time (hr)

Dig

esti

bilit

y (%

)

Ae waxy corn High amylose VHigh amylose VII Potato

CONCLUSION

Results described and discussed in the present study show not only the existence of the differences related to the maize grain starch grain, its structure and functional properties, components mostly affecting maize yield as a basic component in the animal feed production, but also the existence of differences in the digestibility of different maize starches and the digestibility of maize grain that depends on the genetic background, i.e. hybrid. These results are comparable with results obtained in leading research centres all over the world.

Considering the role and the application of starch in animal feed, its chemical structure, functional properties and the digestibility represent unavoidable and very fundamental parameters.

The most important chemical characteristic and the reason for maize advantage over other cereals in animal nutrition is certainly its high starch content, i.e. the high energy content.

These studies are a contribution and the starting point for further studies of the fundamental and practical importance within the field of the utilisation of maize, the most important natural renewable raw material for our country in the sustainable animal feed production.