1. In- vitro CARBOHYDRATE DIGESTIBILITY OF SOME PEARL MILLET HYBIDS AND COUSCOUS PRODUCED FROM THEM
Nkama, I; B. C. Hamaker; I. Angarwai; .Shelleng, A.B; Diarra.M and B. Bababe

2. INTRODUCTION
Pear Millet (Pennisetum glaucum) is a staple food for countries in Asia and Africa. Nigeria, Mali, Burkina-Faso, Senegal and Niger account for the major quantity of pearl millet produced in West Africa.
Millet is an excellent source of energy and a relatively good source of protein, some vitamins and minerals (Nkama et al., 2003).
Millet hybrids refer to the offspring of two different specie where single cross hybrids are made with cytoplasmic/genic male sterile seed parent and pollen parents that restore male fertility.
Digestibility is the breakdown of proteins, carbohydrates and lipids in a food system by enzyme either in vitro or in vivo.
The rate of digestibility of a substrate can be accelerated or slowed even impeded by enzymes and their inhibitors.
Couscous is an agglomerated, steamed – cooked product processed from millet, sorghum, maize and wheat (Galiba et al., 1987.

3. The objective of this study
To determine the effects of processing of pearl millet hybrids into couscous on their in vitro carbohydrate digestibility.

4. MATERIALS AND METHODS
Nine pearl millet hybrids, two improved varieties and one Farmers’ Local usedin the study were obtained from Lake Chad Research Institute, Maiduguri.
Shekib’s et al. (1988) method was used for in vitro carbohydrate digestibility determination.
The grains hardness and dimensions was determined using grain hardness tester (Model l Euweka. TBH 30, Germany). The grains were placed into the machine and mechanical force applied on them and readings obtained were recorded on the recorder.

5. MATERIALS AND METHODS
Couscous was made from cleaned dehulled millet grain by grinding, sieving to obtain fine flour.
The flour was mixed with water to form dough which was passed through a coarse sieve to obtain agglomerates.
The agglomerates was steamed on a perforated pot and then dried to safe moisture levels.

6. Table 1: In- vitro carbohydrate digestibility of pearl millet hybrids and couscous produced from them
Sample
Hardness (N)
Diameter (mm)
Digestibility (%)
Pearl Millet Hybrids
Couscous
Time (min) 10 30 60
LCIC MH 99-39
45.20abc
2.261abc
3.205f
11.22g
29.48i
17.50fe
49.17c
82.50a
LCIC MH 99-23
36.80c
2.482 a
3.436f
12.09g
38.14i
13.21f
36.47f
61.00g
LCIC MH 99-31
34.40c
2.432 ab
12.50bc
29.04b
47.58f
14.78ef
42.26de
71.13de
LCIC MH 99-25
40.40bc
2.187cd
13.65b
41.24 a
50.44 e
27.33ab
43.17d
69.17e
LCIC MH 99-26
37.80c
2.068cd
9.717d
39.81a
55.80 d
25.59bc
51.19c
76.84c
LCIC MH 99-10
52.90a
2.084cd
13.50b
2926c
61.74b
21.76d
39.61e
80.20ab
LCIC MH 99-33
42.20abc
2.253abc
13.04 bc
31.67b
44.09a
29.78a
56.04b
72.33d
LCIC MH 99-12
49.40bc
2.152cd
19.09a
30.91f
64.09a
20.58d
59,81a
79.42b
LCIC MV-1
39.30cb
1.973d
12.46bc
25.23d
62.30b
24.53d
49.05c
73.58d
FARMERS LOCAL
40.30bc
2.167cd
s.898b
19.991e
46.90g
27.52ab
41.28de
56.51b
SOSA1-C88
44.10abc
2.065cd
6.514a
16.15f
46.17 g
13.13f
26.25g
63.13g
LCIC 9702
34.50c
2.211bcd
11.689c
40.59a
58.58c
17.20a
50.81c
66.40f

7. RESULTS AND DISCUSSION
Processing increased the in vitro digestibility of carbohydrate no matter the initial digestibility of the hybrid.
Generally most of the hybrids had better digestibility compared to the improved cultivars and farmers’ Local when processed into couscous.
Couscous from a low digestibility hybrid can be more digestible than that made from a high digestibility hybrid.