Karatina
University
EXPLORING THE POTENTIAL OF KENYAN ORANGE
FLESHED SWEET POTATO (Ipomoea batatas Lam)
PUREES FOR FUNCTIONAL FOOD PRODUCTION.
Muchiri M. Njeri and McCartney Anne L.
[email protected]
Karatina
University
INTRODUCTION
BACK GROUND OF RESEARCH AIM OF RESEARCH
 MDG 1:Eradicate extreme
poverty & hunger (Eradication
of poverty to < 30 % by 2015)
 MDG 4 & 5: Improvement of
child and maternal health
respectively( Vitamin A and
other micronutrients
 Kenya Vision 2030-Economic
Pillar by value addition of OFSP
agricultural fresh food
 Food and Nutrition Security at
National and House hold/
Individual level( Available.
Affordable, Accessible
To investigate whether puree (paste)
from orange fleshed sweet potato
can be utilized to enhance quality
of processed foods in terms of :
-Nutritional (micronutrients, βcarotene, calories & fiber),
- Physiochemical( dry matter/bulk,
viscosity, pH, color)
- Sensory(organoleptic):
Appearance, Flavor, Texture
- Functional properties/ingredients
Karatina
University
ROOT TUBER OF ORANGE
FLESHED SWEET POTATO
(OFSP) (Ipomoea batatas Lam
High yielding & adaptable but
perishable tropical crop
VARIATIONS
- Texture
- Color (Skin $ Flesh
- Composition
PREVIOUS STUDIES
- Improve agronomic characteristics
(yield, disease resistance
-Formulate home based food products
(Cakes, Mandazi, Porridge flour, Crisps)
- Treat Vitamin A deficiency/boost
CURRENT STUDY
FUNCTIONAL FOOD
Def: Foods with health promoting benefits
and/or prophylactic properties over
and above usual nutritional value –
Phytochemicals, Probiotics(beneficial live
microbes, prebiotics (non-digestible
food ingredient that selectively
stimulate colon bacteria)
POTENTIAL FOOD PRODUCTS
- Alcoholic and non beverages
- Baby foods
- Bakery: Cakes, bread
- Dairy products: Yoghurt
- Snacks: Crisps
Explore the potential of formulating OFSP-enriched probiotic/synbiotic
yoghurt.
Karatina
University
METHODOLOGY
THE DYNAMICS OF FOOD PRODUCT
DEVELOPMENT
ASSESS COMMUNITY
NUTRITIONAL
NEEDS, FOOD
HABITS/ PATTERNS
& POTENTIAL FOOD
BUSINESSES
FORMULATE $
ANALYSE
FOOD PRODUCT
INTRODUCE $
EVALUATE
ACCEPTABILITY
OF FOOD
PRODUCT IN
THE
COMMUNITY /
MARKET
FORMULATION $ ANALYSIS
OFSP ENRICHED YOGHURT
 Analysis of raw material (3
varieties of OFSP common
in Kenya: SPK 004, Tainung
& Nasport
 Physiochemical properties
(Color, pH,
 Nutritional (Dry
matter/moisture, βCarotene(provitamin A),
Crude fiber,
Starch, Total sugar
 Production of OFSP Puree
(Simple boiling for 30 minutes
with peels for minimal
nutrient and sensory
degradation
 Fermentation with
commercial yoghurt
culture microbes and
probiotic microbes.
Karatina
University
RESULTS
PHYSIO-CHEMICAL CHARACTERISTICS OF OFSP PUREES
Table 1: Hunters CIE colour scale analysis of different OFSP products
Left to right: Tainung (Op),
Naspot (Yp), and SPK 004 (Rp).
Appealing yellow to dark orange colors
associated with health.
Flowability: Thick- Light
OFSP product
SPK 004 fresh (Rf)
SPK 004 puree (Rp)
Tainung fresh (Of)
Tainung puree (Op)
Naspot fresh (Yf)
Naspot puree (Yp)
L*
81.51 ± 0.21
47.46 ± 0.06
68.43 ± 1.47
41.58 ± 0.07
78.31 ± 3.00
45.32 ± 0.07
a*
7.62 ± 1.86
2.57 ± 0.16
28.96 ± 0.22
10.02 ± 0.14
11.72 ± 2.24
-0.73 ± 0.13
pH: 6.4-6.6
b*
30.67 ± 13.29
18.38 ± 8.82
35.86 ±12.65
16.98 ± 6.13
30.59 ± 11.91
15.10 ± 8.35
E
87.46
50.96
82.18
46.00
83.37
47.79
Karatina
University
NUTRITIONAL
CHARACTERISTICS
80
60
40
20
0
SPK 004 Tainung Naspot
(R)
(O)
(Y)
Beta carotene
(mg/100g [DWB])
Moisture content
(%)
100
20
15
10
5
0
SPK 004 Tainung Naspot
(R)
(O)
(Y)
2
1
0
SPK 004 (R)
Tainung (O)
Naspot (Y)
Starch (% FWB)
Crude fibre
(% FWB)
3
30
20
10
0
SPK 004 Tainung Naspot
(R)
(O)
(Y)
Sugar (% DWB)
35
30
25
20
15
10
5
0
Rf
Boiling reduces microbial load →
Prolonged shelf-life
Yf
Yp
Of
OFSP Variety
MICROBIAL STANDARDS
 Fresh OFSP:
350 - 520 CFU/g
OFSP Puree
<10 CFU/g
High hygiene standards
Rp
Op
CONCLUSIONS & RECOMMENDATIONS
OFSP cultivars have desirable physiochemical,
nutritional and microbial quality attributes
that have a future beyond home usage for
production of safe processed functional foods.
Investigate the stability of OFSP ingredients
during heat processing in various food
matrices
Partnership with private sector for effective
commercialization of formulated product.
Asante
Thank you !!!
Acknowledgement