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Knowledge, use and sensory evaluation of red palm oil ogi by caregivers in Makurdi, Nigeria.

INTRODUCTION

Vitamin A is a vital micronutrient associated with the development of children's immune as well as visual systems and essential for optimal health, growth and development [1, 2]. Vitamin A deficiency (VAD) has been identified as a major public health challenge in many developing countries of the world affecting mainly children under five years of age (U5) [3, 4, 5, 6]. Vitamin A deficiency contributes to the incidence of sight problems and severity of life-threatening infections like diarrhoea and measles as well as mortality from malaria [7, 8, 9]. Furthermore, VAD may be a major cause of U5 mortality in Nigeria. The Micronutrient Initiative (MI) and the National Committee on Food and Nutrition of Nigeria (NCFN) recently reported a prevalence of 29.5% of VAD amongst children under 5 years of age in Nigeria [10].

Several strategies have been employed to combat VAD and these include fortification of food ingredients like flour and vegetable oil, administering vitamin A supplements and bio-fortification. However, the food-based approach appears to be the most sustainable in developing countries. Consequently, emphasis is being placed on dietary diversification and food-to-food fortification subject to availability and affordability of targeted local foodstuffs. These efforts include the inclusion of pro-vitamin A rich sources such as carrots and orange fleshed sweet potatoes in complementary foods.

Given red palm oil's high carotenoid contents, about 10.1g/d of red palm oil (RPO) has been estimated to supply 100% of the vitamin A requirement of a 4-6 year old child; that is 450 retinol equivalents per day which according to USDA/ARS is about 2.2 teaspoons per day [11, 12]. Hence, it is recommended for incorporation into complementary foods by health workers in Nigeria [13, 14, 15]. However, it is not known how many caregivers understand and practice this approach in their homes and the challenges that may be confronting them. This study ascertained the extent of knowledge, use and sensory evaluation of red palm oil in ogi (a traditional cereal-based porridge consumed by children below 5 years of age) and highlights some of the challenges confronting this potentially useful food-based approach in combating vitamin A deficiency (VAD) in Nigeria.

MATERIALS AND METHODS

Research design: The study adopted a descriptive survey design [16]. Purposive sampling was used to select hospitals while individual respondents were selected based on their willingness to participate [17]. A total of 100 respondents participated.

Respondents: The study population consisted of caregivers attending antenatal and postnatal check-ups in three well attended Government hospitals within Makurdi, Nigeria.

Instrumentation: In this study, quantitative (survey) and qualitative methods (focus group discussion) were adopted [16]. For the survey, a pre-tested questionnaire was used to obtain information from the participants. The questionnaire contained open-ended and close-ended questions. A question guide was employed in two separated groups for the focus group discussion sessions using a total of 17 participants.

Method of data collection: The questionnaires were administered to the participants on a one-on-one basis and on-the-spot retrieval was ensured on completion. Data were statistically analyzed using the SPSS version 16.0 statistical software package. Percentages of the frequency counts were used to describe information given by the respondents. The focus group discussions involved two personnel, the moderator of the FGD assisted by a secretary. Each session lasted 30-45 minutes using an audio recorder to collect responses which were subsequently summarized [18].

Sensory evaluation: The panelists involved 15 caregivers. Consent was sought followed by a brief training on how to score the samples. The sensory attributes were rated using a 9-point Hedonic scale where 9= like extremely, 8= like moderately, 7= like slightly, 6=like, 5=neither like nor dislike, 4=dislike, 3= dislike slightly, 2= dislike moderately and 1= dislike extremely [19]. Data collected were subjected to one-way analysis of variance (ANOVA) at 5% level of significance.

Ethical approval of the study

The research protocol was approved by the Ethics Committee of each of the government hospitals selected and a written consent was sought from the participants before their participation in the study.

RESULTS

The socio-demographic characteristics of the respondents are presented in Table 1. Most caregivers were between the ages of 26 and 35 years (52%) and possessed either a secondary or tertiary education qualification (87%). Only 47% were full-time home managers. The rest (53%) were employed outside of their homes.

Information on the use of complementary foods (CF) by caregivers in Makurdi, Nigeria is presented in Table 2. All the respondents indicated that they fed their children under 5 years of age with CF. While 21% fed their children exclusively with locally prepared CF, 79% adopted commercial CF in combination with local CF for complementary feeding. Most caregivers (78%) introduced CF from six months and above daily (93%) using cups and spoons (53%), feeding bottle (27%) as well as plate and spoons (20%). The CF of choice were usually given to the children at a daily frequency of three (52%) or four (35%) times.

Respondents' knowledge on the processing and preparation of ogi in Makurdi, Nigeria is summarised in Table 3. Most (98%) caregivers could process cereal grains into ogi. Most preferred millet (76%) for ogi processing. The preferred duration of soaking and fermentation of cereal grain was 24hrs.

Information on caregivers' knowledge and willingness to adopt RPO ogi in Makurdi, Nigeria is summarised in Table 4. While 99% of respondents had used red palm oil as a food ingredient, only 11% indicated ever using RPO in ogi preparation. Of those that used RPO in ogi, most (53.8%) used two spoons of RPO (10mls) per cup of ogi (approx 100g) for their children daily (76.9%). All the caregivers indicated that there was no known taboo against the use of RPO in the meals of children below 5 years of age. However, only 17% of respondents were willing to feed their children with RPO ogi. While 42% were not willing to use RPO ogi, 41% were indifferent in their disposition towards RPO ogi.

Two separate Focus Group Discussions (FGDs) were held to verify the information obtained from the survey. In terms of cereal preference and duration of fermentation for ogi, most respondents indicated preference for millet grains fermented for less than 48hrs for ogi preparation. In addition to ogi, the FGD listed other CFs frequently fed to children below 5 years of age to include beans, rice, mashed yam, custard, pasta products and family meals in general. The choice of complementary food to use by caregivers depended on availability, affordability, child's preference and beliefs in that respective order. Furthermore, while the respondents indicated that RPO was a taboo-free, popular food ingredient; none had thought of, or had been informed about incorporating RPO in ogi. Equally, none was aware of the benefits of adding RPO in the preparation of ogi. However, most participants in the FGD indicated willingness to incorporate RPO in ogi if the method of preparation was demonstrated and RPO ogi presented no adverse effects on the child.

The result of sensory evaluation of RPO ogi from maize and millet is presented in Table 5. While the 'appearance' of RPO ogi at 10% (w/v) was adjudged to be better than the control ogi when maize was employed, the 'appearance' of RPO ogi was consistently scored lower than the control ogi for all sensory attributes when millet was used. In addition, the score for 'texture' of RPO ogi decreased with increasing RPO concentration while the scores for 'taste' in both maize and millet RPO ogi increased with RPO concentration. In terms of 'overall acceptability', the control ogi samples from both maize and millet scored better than their RPO counterparts. Ogi with 5, 10 and 15% (w/v) RPO scored 6.8, 6.6 and 5.4 for maize and 5.9, 6.0 and 5.2 for millet, respectively for 'overall acceptability'.

DISCUSSION

The majority of the respondents were literate adult mothers and were, as expected, knowledgeable about complementary food preparation. Previous research has shown a positive relationship between level of education and nutrition knowledge [20]. In addition, allocation of time for the preparation of local CF may not be difficult for most caregivers as they are mostly either home managers or self employed.

A significant number (21%) of respondents rely wholly on locally prepared CF as sources of nutrients for their children below 5 years of age. Complementary food is normally recommended as from six months to augment breast milk nutrient shortfalls for the rapidly growing child [21, 22]. In this study, it is noteworthy that adherence to the recommended age (6 months) for introducing CF by the caregivers (78%) was higher than the national figure for exclusively breast-fed children presumably because the respondents in this study were more educated than the average Nigerian population.

In addition to the 21% relying exclusively on locally prepared CFs, 79% of caregivers combined locally prepared CFs with the commercial samples in feeding their children. It has been previously observed that no single complementary food was capable of providing adequate nutrients to meet the daily nutrient requirements for children below 5 years of age [23]. This might partly explain the high incidences of VAD in many parts of Nigeria as most locally prepared CFs are prepared exclusively from low vitamin A sources such as cereals and tubers. Therefore, the practice of incorporating pro-vitamin A-rich red palm oil in CFs such as ogi could be helpful in improving local CFs pro-vitamin A content and energy values. It may be necessary however, to quantify the actual contribution of this approach to the total vitamin A recommended daily allowance (RDA) for children under 5 years of age living in this region. Furthermore, given that foods prepared with RPO are highly prone to rancidity, studies may be required to ascertain the shelf stability of dry RPO ogi. In the interim, addition of RPO to ogi at the point of preparation of the wet paste is recommended to avert the potential challenge of rancidity.

It is noteworthy that most caregivers in Makurdi prefer millet in the preparation of ogi compared to maize in many parts of Nigeria due to existing perception that millet is more nutritious and possesses desirable flavour. Furthermore, the most preferred duration of fermentation for ogi preparation in this study ([less than or equal to] 24 h) is lower than the 24-72 h recommended by previous workers, further indicating possible regional variations in the preparation of ogi across Nigeria [24].

Although the respondents in this study considered red palm oil (RPO) to be a taboo-free cooking ingredient, the low adoption of RPO ogi might have been due to low awareness and knowledge of its preparation. Adoption of this food-based approach could be easily enhanced through proper nutrition education and demonstration of the preparation techniques and benefits of utilizing RPO ogi. Some researchers have used RPO in other foods to intervene in VAD with some success [25, 26].

The focus group discussion confirmed most of the information obtained from the survey. For instance, most caregivers in the FGDs preferred millet for ogi preparation just as was the case in the survey. In addition, the factors affecting the choice of CF as stated by caregivers were consistent with a previous report [27].

Acceptable RPO ogi could be prepared from both maize and millet at 5-10% (w/v) since scores of 6 or 7 correspond to 'like' and 'like slightly' on the 9-point Hedonic scale, but higher RPO concentrations resulted in lower scores on some sensory criteria. High RPO concentration led to ogi with poor textural properties owing possibly to poor oil-starch interactions resulting in low gel strength and viscosity [28]. Consequently, the promotion of red palm oil in the preparation of ogi should begin with lower concentrations.

CONCLUSION

The findings from this study suggest that the level of awareness on the use of red palm oil ogi in Makurdi, Nigeria is low. Gaps identified include ignorance on the nutritional benefits of red palm oil to the health of children below 5 years of age as well as method of preparation and concentration of red palm oil to be employed in red palm oil ogi. A significant number of caregivers may be willing to adopt red palm oil ogi if taught how to prepare it with no adverse effects on the child. Acceptable red palm oil ogi can be prepared using either millet or maize at 5-10 % (w/v) red palm oil concentration. Nutrition education on the use of affordable, pro-vitamin A-rich food sources such as red palm oil in ogi should be strengthened. Areas of further studies should include physicochemical properties and storage stability of red palm oil ogi. In addition, clinical trials should be carried out to determine the actual contribution of red palm oil ogi to serum retinol level in children under 5 years of age.

ACKNOWLEDGEMENTS

The Authors are grateful to University of Agriculture, Makurdi, Nigeria for funding this study in part. Additional technical support for this work was provided by the UNICEF-TI Consultative Meeting Group, Nigeria. Prof. F.N Onyezili currently of College of Science, University of Agriculture, Makurdi, Nigeria for initiating the University of Agriculture, Makurdi, Nigeria Task-Force on Rising Food/Commodity Prices, Coping Mechanism, Complementary Feeding and Control/Management of Childhood Malnutrition.

REFERENCES

[1.] Bagriansky J and P Ranum Vitamin A Fortification of P.L. 480 Vegetable Oil. SUSTAIN, Washington D.C. 1999.

[2.] United Nations Children's Fund (UNICEF). Information Sheet: Nutrition. UNICEF Nigeria, 2006; 1-2.

[3.] Maida JM, Mathers K and CL Alley Pediatric Ophthalmology in the Developing World. Curr Opin Ophthalmol 2008; 19:403-408.

[4.] World Health Organization (WHO). Global Prevalence of Vitamin A Deficiency in Populations at Risk From 1995-2005. WHO Global Database on Vitamin A Deficiency. Geneva, Switzerland: World Health Organization, 2009.

[5.] Li S, Nugroho A, Rocheford T and WS White Vitamin A Equivalence of the P-Carotene in P-Carotene-Biofortified Maize Porridge Consumed by Women. Am J Clin Nutr. 2010; 92: 1105-1112.

[6.] Maziya-Dixon B, Akinyele IO, Sanusi RA, Oguntona TE, Nokoe SK and EW Harris Vitamin A Deficiency is Prevalent in Children Less Than 5 Years of Age in Nigeria. J. Nutr. 2006; 136: 2255-2261.

[7.] Beaton GH, Martorell R and KJ Aronson Effectiveness of Vitamin A Supplementation in the Control of Young Child Morbidity and Mortality in Developing Countries. ACC/SCN State-Of-The-Art Series. Nutrition Policy Discussion Paper No. 13. Geneva, Switzerland: United Nations Administrative Committee on Coordination/Subcommittee on Nutrition, 1993.

[8.] Shankar AH, Genton B and RD Semba Effect of Vitamin A Supplementation on Morbidity Due to Plasmodium Falciparum in Young Children in Papua New Guinea: A Randomised Trial. Lancet 1999; 354: 203-209.

[9.] Rice AL, West KP and RE Black Vitamin A Deficiency. In: Ezzati M, Lopez AD, Rodgers A, Murray CJL, eds. Comparative Quantification of Health Risks: Global and Regional Burden of Disease Attributable to Selected Major Risk Factors. Vol 1. Geneva, Switzerland: World Health Organization, 2004.

[10.] Ojotimehin EO A Paper Presentation on Malnutrition and Approaches to Improving the Nutritional Status of Children in Low Income Settings. 2007.

[11.] Burri BJ Evaluating global barriers to the use of red palm oil as an intervention food to prevent vitamin A deficiency. Comprehensive Review in Food science and Food safety, 2012; 11: 221-232.

[12.] United States Department of Agriculture Agricultural Research Service (USDA ARS). National nutrient database for standard reference, Release 23. Washington, D.C.: USDA. Available from: http://www.nal.usda.gov/fnic/foodcomp/search/. Accessed 2011 June 19.

[13.] Edem DO Nutritional, physiological and therapeutic roles in improving human well-being and quality of life. Plant Foods for Hum. Nutr., 2002; 57(3-4): 319-341.

[14.] Oguntibeju OO, Esterhuyse AJ and EJ Truter Red palm oil: nutritional, physiological and therapeutic roles in improving human wellbeing and quality of life. Br. J Biomed Sci. 2009; 66(4): 216-222.

[15.] Colin WB, Ronald EP and WW Delmer Palm Oil: A Pilot Study of its Use in a Nutrition Intervention Programme. J. Trop Pediatr. 1984; 30 (5): 272-274.

[16.] Salant P and DA Dillman How to Conduct Your Own Survey. John Wiley and Sons. New York, 1994.

[17.] Glasow PA Fundamentals of Survey Research Methodology. Mitre press. Washington DC, 1995; 2:1-2.3.

[18.] Wilkinson S Focus Groups: A Feminist Method. In Hesse-Biber, SN and Yaiser, ML (Eds.), Feminist Perspectives on Social Research. Oxford University Press, New York. 2004: 271-295.

[19.] Ihekoronye AI and PO Ngoddy Integrated Food Science and Technology for the Tropics. Macmillan Publishers, London, 1985.

[20.] Ko S, Lee TK and GS Guldan Dietary Intake, Food Habits and Nutrition Knowledge of Adults--A Telephone Survey in Hong Kong. Nutr. Res. 1995; 15(5): 633-645.

[21.] Egounlety M, Aworh OC, Akingbala JO, Houben JH and MC Nago Nutritional and Sensory Evaluation of Tempe-Fortified Maize-Based Weaning Foods. Int. J. Food Sci. Nutr., 2002; 53(1): 15-27.

[22.] Nnam NM Chemical Evaluation of Multimixes Formulated from Some Local Staples for Use as Complementary foods in Nigeria. Plant Foods for Hum. Nutr. 2000; 55: 255-263.

[23.] World Health Organization (WHO). Global Strategy for Infant and Young Child Feeding. World Health Organization, Geneva. 2003. Available at http://whqlibdoc.who.int/publications/2003/9241562218.pdf. Accessed on September 10, 2010.

[24.] Ijabadeniyi AO and TT Adebolu The Effect of Processing Methods on the Nutritional Properties of "Ogi" Produced from Three Maize Varieties. J. Food, Agric & Evt. 2005; 3(1): 108-109.

[25.] Khosla P Palm oil: A Nutritional Overview. Agrofood Industry Hi-tech. 2006; 17 (3): 21-23.

[26.] Kusum R, Bommayya H, Fayaz PP and HD Ramachandran Palm Oil and Rice Bran Oil: Current Status and Future Prospects. Int. J. Plant Physiol. Biochem. 2011; 3(8): 125-132.

[27.] Igah SA Target Food Sources for Formulating Complementary/Supplementary Foods for Weaning Purposes--A Review. Bajopas. 2008; 1(1): 20-27.

[28.] Johnson JM, Davis EA and J Gordon Interactions of Starch and Sugar Water Measured by Electron Spin Resonance and Differential Scanning Calorimetry. Cereal Chem. 1990; 67(3): 286-291.

Adewuyi OA * (1), Abu JO (2), Amuta EU (3), Abu GA (4), Iombor TT (5) and EK Ingbian (6)

Corresponding author email: olufix07@yahoo.co.uk

(1) Graduate student, Department of Food Science and Technology, University of Agriculture PMB 2373 Makurdi, Nigeria

(2) Associate Professor and Head, Department of Food Science and Technology, University of Agriculture Makurdi, Nigeria Email; joabuza@yahoo.co.uk

(3) Professor and Dean, Postgraduate School, University of Agriculture Makurdi, Nigeria

(4) Asssociate Professor, Department of Agricultural Economics, University of Agriculture Makurdi, Nigeria

(5) Lecturer I, Department of Home Science and Management, University of Agriculture Makurdi, Nigeria

(6) Associate Professor, Department of Food Science and Technology, University of Agriculture Makurdi, Nigeria (Now Deceased)
Table 1: Socio-demographic characteristics of caregivers
in Makurdi, Nigeria (n = 100)

                    Characteristics    n     Percentage

Age (years)         16-25              42    42.0
                    26-35              52    52.0
                    36-45              4     4.0
                    46-55              2     2.0

Religion            Christianity       92    92.0
                    Islam              5     5.0
                    Others             3     3.0

Educational level   Primary            5     5.0
                    Secondary          40    40.0
                    Tertiary           47    47.0
                    No formal          8     8.0

Profession          Civil servant      13    13.0
                    Public servant     6     6.0
                    Self employed      34    34.0
                    Home manager       47    47.0

Table 2: Use of complementary food by caregivers in Makurdi,
Nigeria (n = 100)

Questions                         Options                 Percentage

What complementary food do you    Commercial only         --

give to your child?               Local only              21.0

                                  Both                    79.0

At what age do you start giving   Below 6 months          22.0

complementary foods?              At 6 months and above   78.0

What feeding tools do you         Plate and spoon         20.0

employ?                           Feeding bottle          27.0

                                  Cup and spoon           53.0

How many times in a day?          Once                    4.0

                                  Twice                   9.0

                                  Thrice                  52.0

                                  Four times              35.0

Table 3: Caregiver's knowledge on the processing and preparation
of ogi in Makurdi, Nigeria (n = 100)

Questions                       Options            Percentage

Can you prepare Ogi?            Yes                98.0

                                No                 2.0

Which cereal grain do you       Maize              18.0
prefer or use in making ogi?
                                Millet             76.0

                                Sorghum            6.0

For how long do you             Less than 24hrs    30.9
soak the grain?
                                24hrs              53.6

                                48hrs              11.3

                                72hrs              2.1

                                96hrs and above    2.1

How long do you allow           Less than 24hrs    42.3
fermentation to take place?
                                24hrs              45.4

                                48hrs              9.3

                                72hrs              1.0

                                96hrs and above    2.1

How do you separate             Sieving            37.1
water from ogi?
                                Decanting          62.9

                                Others             --

Table 4: Caregiver's knowledge and willingness to adopt red
palm oil ogi in Makurdi, Nigeria (n=100)

Questions                         Attributes          Percentages

Have you ever used red palm       Yes                 99.0
oil as cooking ingredient?
                                  No                  1.0

How often do you use it?          Daily               92.9

                                  Weekly              7.1

Have you ever mixed red palm      Yes                 11.0
oil with ogi and served as        No                  89.0
complementary food?

If yes, at what ratio of red      * 1 spoon : 1 cup   38.5
palm oil to ogi?                  2 spoons : 1 cup    53.8
                                  3 spoons : 1 cup    7.7
                                  4 spoons : 1 cup    --

Would you like to feed your       Yes                 17.0
child with red palm oil ogi?      No                  42.0
                                  Indifferent         41.0

If yes, how often?                Daily               76.9
                                  Weekly              23.1

Is there any belief or taboo      Yes                 --
against consumption of red palm   No                  100.0
oil by U5 children in your
community?

* Ratio of red palm oil to ogi. 1 spoon is equivalent
to 5mls and 1 cup is equivalent to 100g of cooked ogi

Table 5: Sensory evaluation of red palm oil (RPO) ogi by
caregivers in Makurdi, Nigeria

                                                RPO Maize
                                                 ogi (5%
Attributes              Maize ogi                 w/v)

Appearance         7.0 [+ or -] 2.5 (b)    7.3 [+ or -] 1.8 (b)
Taste              6.7 [+ or -] 2.6 (b)    6.4 [+ or -] 2.2 (c)
Aroma              6.1 [+ or -] 3.0 (c)    6.7 [+ or -] 1.9 (b)
Texture/           7.9 [+ or -] 2.4 (a)    7.5 [+ or -] 1.3 (a)
  Mouth feel
Overall            7.4 [+ or -] 2.7 (a)    6.8 [+ or -] 3.0 (ab)
  acceptability

                         RPO Maize                  RPO
                         ogi (10%                Maize ogi
Attributes                 w/v)                  (15% w/v)

Appearance         7.9 [+ or -] 1.4 (a)    6.0 [+ or -] 3.0 (d)
Taste              6.9 [+ or -] 2.3 (b)    6.1 [+ or -] 2.6 (c)
Aroma              6.2 [+ or -] 2.4 (c)    5.7 [+ or -] 2.4 (d)
Texture/           6.4 [+ or -] 2.8 (b)    6.2 [+ or -] 2.7 (b)
  Mouth feel
Overall            6.6 [+ or -] 2.6 (b)    5.4 [+ or -] 2.7 (cd)
  acceptability

                                                RPO Millet
                        Millet ogi                ogi (5%
Attributes                                         w/v)

Appearance         7.4 [+ or -] 2.7 (b)    6.7 [+ or -] 2.3 (c)
Taste              7.9 [+ or -] 2.5 (a)    6.4 [+ or -] 2.2 (c)
Aroma              7.3 [+ or -] 2.5 (a)    5.4 [+ or -] 2.6 (d)
Texture/           7.1 [+ or -] 1.9 (ab)   6.5 [+ or -] 1.8 (b)
  Mouth feel
Overall            7.1 [+ or -] 2.9 (a)    5.9 [+ or -] 2.9 (c)
  acceptability

                        RPO Millet              RPO Millet
                         ogi (10%                ogi (15%
Attributes                 w/v)                    w/v)

Appearance         6.6 [+ or -] 2.4 (c)    5.9 [+ or -] 2.4 (d)
Taste              7.1 [+ or -] 2.2 (b)    4.7 [+ or -] 2.6 (d)
Aroma              6.3 [+ or -] 1.9 (c)    4.5 [+ or -] 2.4 (e)
Texture/           6.0 [+ or -] 2.3 (bc)   5.7 [+ or -] 2.7 (c)
  Mouth feel
Overall            6.0 [+ or -] 3.1 (c)    5.2 [+ or -] 3.1 (d)
  acceptability

Values with different letters are significantly
different (p<0.05).

Keys: 9-like extremely

8- like moderately

7- like slightly

6- like

5- neither like nor dislike

4- dislike

3- dislike slightly

2- dislike moderately

1- dislike extremely
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Author:Adewuyi, Olufemi A.; Abu, J.O.; Amuta, E.U.; Abu, G.A.; Iombor, T.T.; Ingbian, E.K.
Publication:African Journal of Food, Agriculture, Nutrition and Development
Article Type:Report
Geographic Code:6NIGR
Date:Apr 1, 2014
Words:3933
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