R. Parimalavalli & S. Kavitha Department of Food Science and Nutrition

Periyar University Salem - 636 011

TamilNaduparimala1996@gmail.com

Complementary food is defined as those which are

appropriately timed, nutritionally adequate and

hygienically prepared foods that are given to

infants along with continued breast feeding from

six months of age. Extrusion cooking is one of the contemporary food

processing technologies applied for preparation of

a variety of snacks and supplementary foods.

To analyze the physical, morphological and sensory

characteristics of Ready-to-Eat (RTE) extruded

complementary foods.

Procurement of Raw Materials (Wheat, maize, Mung bean and

Groundnut)

Procurement of Raw Materials (Wheat, maize, Mung bean and

Groundnut)

Composit ion of Complementary Food by

Material Balance Method (Wheat – 39%, Maize – 34 %,

Mung bean – 14 % and Groundnut – 13 %)

Composit ion of Complementary Food by

Material Balance Method (Wheat – 39%, Maize – 34 %,

Mung bean – 14 % and Groundnut – 13 %)

Processing of Raw Materials Processing of Raw Materials

Physical PropertiesMorphological analysis – SEM

Organoleptic Qual it ies

Physical PropertiesMorphological analysis – SEM

Organoleptic Qualit ies

Extrusion Process – Twin Screw Extruder

Extrusion Process – Twin Screw Extruder

Raw Ingredients

Wheat Maize Mungbean Groundnut

Processing of Raw Ingredients

Composite Flours

Extruded Complementary

Foods

Control GerminationRoasting

Table – 1 Physical Charactersitics of Extruded Complementary foods

CECF – Control Extruded Complementary Food, RECF – Roasted Extruded Complementary Food,

GECF – Germinated Extruded Complementary Food.

Physical Characteristics CECF RECF GECF F Ratio

Length (mm)Diameter (mm)Specific VolumeExpansion RatioMass Flow Rate (gs 1‑ )Residence Time (S)Specific Mechanical Energy (kj/kg)Bulk Density (g/ml)WAI (g/g)WSI (%)

4.94±0.64a

2.60±0.30 a

2.76±0.63 a

3.64±0.13 a

1.36±0.21 a

77.6±1.26 a

818.25±3.65 a

0.96±0.02 a

3.59±0.65 a

16.98±1.21 a

3.88±0.85b

2.47±0.20 b

2.62±0.42 b

3.03±0.57 b

1.13±0.42 b

68.65±1.03 b

864.74±5.68 b

0.94±0.01 b

3.04±0.53 b

15.40±0.98 b

3.71±0.54 c

2.42±0.23 c

2.89±0.35 c

2.43±0.27 c

0.98±0.26 c

54.06±1.12 c

968.31±4.75 c

0.98±0.02 c

4.21±0.45 c

18.64±0.84 c

9.36**3.89*

4.98**8.02**4.89**7.46**9.87**0.09 NS

5.36**6.58**

•CECF had high 4.94 mm length, 2.60mm diameter, 3.64

expansion ratio, 56.25 T, 1.36gs 1‑ MFR and 77.6 sec

residence time. GECF had high 2.89 specific volume,

968.31kj/kg specific mechanical energy, 0.98g/ml bulk

density, 4.21g/g water absorption index and 18.64% water

solubility index.

A - CECF – Control Extruded Complementary Food, B - RECF – Roasted Extruded Complementary Food, C - GECF – Germinated Extruded Complementary Food.

Morphological Analysis of Extruded Complementary foods

A B C

•Absence of starch granule in all samples indicated starch has

been completely gelatinized. Extrudates showed large numbers

of flattened and sheared granules. The highest damage was seen

during extrusion in germinated samples followed by control

and roasted samples.

•Control sample displayed a porous, open celled structure

devoid of air cells may be due to less expansion and high shear

stress.

•Roasted extruded complementary food showed a

discontinuous flattened granular structure with few air cell

embedded inside the layer. A higher air cells in the roasted

extrudate compared to control extrudate indicates that a higher

magnitude of expansion was occurred due to roasting.

•Germinated extrudate displayed a smooth surface morphology

indicated gelatinization of starch component and porous layer.

The outer core of the extrudate appeared to have a protein coat

associated with the starch granules since germinated extruded

complementary food is recorded with a elevated levels of

protein.

Table – 2 Organoleptic Qualities of Extruded Complementary foods

Characteristics CECF RECF GECF

ColourFlavourTasteTextureOverall acceptability

6.52±0.30a

3.59±0.24 a

4.23±0.86 a

4.40±0.92 a

5.01±0.57 a

5.42±0.88 b

4.94±0.46 b

6.70±1.30 b

5.78±0.93 b

7.14±0.91 b

5.06±0.73 c

3.04±0.43 c

5.20±0.86 c

6.04±0.52 c

6.20±0.15 c

•The range of scores for attributes was: colour (4.52 to

5.92), flavour (3.59 to 4.94), taste (4.23 to 6.70),

texture (4.40 to 6.04) and overall acceptability (5.01 to

7.04).

•RECF was highly acceptable with mean score of 7.14.

Their acceptability level was significantly higher

(P < 0.05) than the rest of samples.

Processing methods markedly affect the

physical, morphological and organoleptic qualities

of complementary foods. Hence the processed

energy dense complementary foods could be

formulated at low cost with locally available

cereals and pulses to promote nutritional status of

infants.