Hetzel et al. (Vol 3, N°3-4, 2005)

¥

Revue Africaine de Santé et de Productions Animales © 2005 E.I.S.M.V. de Dakar

A RTICLE ORIGINAL Milk consumption patterns in an area with traditional milk production: data from a case control study in peri-urban Bamako Mali M.W. HETZEL1, B. BONFOH1,2*, Z. FARAH3, C.F. SIMBE4, O.I. ALFAROUKH2, J. ZINSSTAG1, 1 2 3 4

Public health and epidemiology, swiss tropical institute, PO Box : 4002 Basel, Switzerland.

Institut du sahel, BP : 1530, Bamako Mali.

Institute of food science and nutrition, swiss federal instituteof technology, PO Box : 8092 Zurich, Switzerland.

Laboratoire central vétérinaire, BP : 2295, Bamako Mali.

*

Correspondance et tirés à part, e-mail : bassirou@agrosoc.insah.org

Abstract During a case-control study in Bamako, Mali, milk consumption habits of 155 people were recorded. Interviews were done by trained interviewers in schools and health centres. Milk and dairy products were consumed by most of the people interviewed during the study. 97.4% of the people declared that they had consumed milk or dairy products at least once in the preceding two weeks. Milk powder was the dairy product most frequently consumed. Fresh raw milk and pasteurised or boiled milk were mostly consumed raw, whereas fermented milk was usually consumed with hot dishes. (RASPA 3 (3-4) : 174-177).

Key – Words: Milk products - Consumption - Bamako.

Résumé Motifs de consommation de lait dans un milieu de production traditionnelle : étude de cas-témoin dans le zone périurbaine de Bamako, Mali Dans une étude de cas à Bamako, Mali, les habitudes alimentaires de 155 individus ont été décrites. Les interviews sont réalisées dans les écoles et les centres de santé par des enquêteurs formés. Le lait et les produits laitiers sont consommées par presque tous les enquêtés. Au total 97,4% des individus déclarent avoir consommé au moins une fois dans les deux précédentes semaines. Le lait en poudre était le produit fréquemment consommé. Le lait cru et le lait bouilli ou pasteurisé sont consommées tel quel alors que le lait fermenté est consommé avec des plats chauds.

Mots-clés : Produits laitiers - Consommation - Bamako

Introduction Mali has a strong tradition of livestock and milk production. The country’s livestock population counts around 6.8 million cattle, 15 million small ruminants and 470’000 camels (Food and Agriculture Organization of the United Nations 2002). Nevertheless, Mali is unable to satisfy its own demand of dairy products and large quantities of milk have to be imported [3]. Mainly as a result of poor hygiene, long transportation periods and lack of appropriate storing equipments, locally produced milk is often heavily contaminated with potentially pathogenic bacteria [1]. In addition, antibiotic residues were found in 6% of milk samples from urban Bamako [2].

Milk and other dairy products are important components of many local dishes. As has been shown by SISSOKO et al. [6], most people are regular consumers of milk and other dairy products in Bamako, Mali. Nevertheless, no recent data are available on milk consumption patterns which could help to target specific measures for developing market opportunities (producers) and for meeting the demand (consumers) for milk and milk products in term consumption of healthy milk promotion.

During a case-control study focused on the public health impact of milk contamination in Bamako [5], the consumption habits of 155 people were recorded. The aim was to contribute to the understanding of the frequency and modes of consumption of milk and other dairy products RASPA Vol.3 N0 3-4, 2005

in the population of Bamako, which may serve as background for future economic and public health considerations. Apart from the frequency of consumption of different dairy products, their mode of consumption in association with other dishes and the relation of socioeconomic status and milk consumption was assessed.

Materials and Methods The study was carried out in Bamako during the dry season from December 2002 to March 2003. Study participants were selected according to the criteria of the case-control study with an approximate case-control ratio of one control per case. Cases were people with diarrhoea or vomiting in the 14 days preceding the interview. Controls without diarrhoea or vomiting in the same period were selected from the same locations as the cases. Both groups were composed of people aged five years or more. Cases and controls were selected during mass screening campaigns in three schools (“Dialakorodji”, “Médina Coura” and “Ibrahima Baba Kaké”) in Bamako, Mali, and in three health care facilities of the city (“Cabinet Médical Dr Yamadou Sidibé”, Community Health Centres of “Dialakorodji” and “Médina Coura”).

After examination by a physician, participants were interviewed using an anonymous structured questionnaire. People were asked detailed questions on their milk consumption in the preceding two weeks. Interviews were done in French or “Bambara” the common local language. The questionnaire was translated and re-translated to assure validity of the questions. Local students were trained as interviewers and supervised during data collection. Intercooled Stata Version 6.0 (Stata Corporation, College Station, USA, 1984-2000) was used for data analysis. A living standard variable was constructed for the households of the participants by assigning an equal weight to each of ten household assets [7]. For analysis, quartiles of the value were calculated. Association was tested for significance by using Chisquared statistics or Fisher’s exact test.

174

M.W. HETZEL et al.

Table 3: Ethnic groups

Results

1. CHARACTERISTICS OF THS STUDY SAMPLE There were slightly more female (57%) than male respondents in the study. 85% of all participants were aged five to 15 years and 85% were interviewed in schools (table 1). 66% of respondent’s households belonged to the lower two quartiles, 34% to the upper two quartiles of the living standard variable (table 2). Most respondents belonged to the ethnic groups of “Bambara” (39%), “Peul” (14%), “Malinké” (12%) and “Sarakolé” (11%) (Table 3).

Table 1: Age structure of the study sample.

Age group 5-10

11-15 16+

Total

Health facilities

female

male 3

0

3

1 2 3 4

Total

12

2

4

42

12

10

Quartile

male

Schools

2

14

56

female 29

male

Total

15

female 29

42

45

44

75

66

89

4

6

16

Table 2: Living standards of households in sample n

Percentage

155

100

44 57 27 27

29 37 17 17

Cumulative percentage

29 66 83 100

2. MILK CONSUMPTION PATTERNS 2.1. Frequency of consumption Milk and dairy products were consumed by most of the people interviewed in the study. 151 (97%) of the people declared that they had consumed some sort of milk or dairy products at least once, 146 (94%) several times in the preceding two weeks. The milk consumption pattern is presented in table 4.

To emphasize the importance of the different products, the two frequency-of-consumption levels “regular consumers” (people having consumed a product several times or every day in the preceding two weeks) and “irregular or nonconsumers” (people with no or one consumption in the preceding two weeks) were introduced (figure 1). According to this classification, milk powder was the most popular product (79% regular consumers), followed by fermented milk (42% regular consumers) and butter (39% regular consumers). Condensed milk, yoghurt en cheese were consumed by relatively few people.

Frequency of consumption of most products was strongly associated with the socio-economic status of the household, defined through the living standard variable (figure 2).

The traditional products fresh raw milk and fermented milk were regularly consumed by people belonging to poorer households, while only around 25% of people from the richest households were regular consumers of these products. Boiled milk, yoghurt, cheese and cream were regularly consumed mainly from people in richer households and consumption of condensed milk was registered almost exclusively in the richest households.

Consumption of milk powder and butter were not significantly

175

Ethnic group

n

Percentage

Bambara Peul Malinké Sarakolé Sonrai Dogon Other Don’t know

61 21 19 17 10 3 23 1

39.35 13.55 12.26 10.97 6.45 1.94 14.84 0.65

Total

155

100.00

associated with the socio-economic status.

Frequency of consumption was not associated with ethnic group or age. Regular consumption of fermented milk was more frequent in female respondents in the schools of “Médina Coura” (p=0.003) and “Dialakorodji” (p=0.003).

2.1. Modes of consumption A descriptive analysis of the mode of consumption demonstrates the specific consumption patterns for different dairy products (table 5). Boiled milk, including pasteurised or other heat-treated milk, was mostly consumed raw (64%) or with bread (13%), which can also be considered as raw consumption. Similar figures apply for fresh raw milk, which was also consumed as a component of couscous (19%). Condensed milk was mainly consumed raw (51%) or with bread (23%) and cream was almost exclusively consumed raw (59%). Fermented milk was usually consumed as a component of hot dishes, e.g. porridge (55%) or couscous (9%). Raw consumption was less frequent (22%). The consumption pattern of milk powder was most diverse. Apart from raw consumption (24%) or consumption with bread (32%), it was used in combination with hot dishes, coffee, tea or cake. Modes of consumption were not associated with ethnic group, age or sex.

74% of the respondents told the interviewers that the fresh or fermented milk they consumed was cow’s milk. Only 3% were consumers of milk of muttons, nobody had consumed goat-milk. 23% did not know from which species their milk came. More than half (52%) of the consumers of fresh or fermented milk said they were boiling their milk prior to consumption.

Table 4: Living standards of households in sample

Milk product

Fresh raw milk Fermented milk Boiled milk Condensed milk Milk powder Yoghurt Cheese Butter Cream

Consumption in the last two weeks (percentage)a

Never n (%)

87 (56) 77 (50) 76 (50) 114 (75) 23 (15) 110 (72) 108 (71) 72 (47) 88 (58)

a Difference to 100 per cent: no response.

once n (%)

12 (8) 12 (8) 27 (18) 12 (8) 9 (6) 15 (10) 15 (10) 21 (14) 17 (11)

several times n (%) 45 (29) 52 (34) 46 (30) 23 (15) 70 (46) 21 (14) 24 (16) 45 (30) 39 (26)

every day n (%) 10 (6) 13 (8) 3 (2) 4 (3) 50 (33) 6 (4) 5 (3) 14 (9) 8 (5)

RASPA Vol.3 N0 3-4, 2005

Milk consumption patterns in an area with traditional milk production

Table 5: Consumption of milk: raw or as component of other dishes.

Dairy product

Mode of consumptiona

N

Number of consumers (percentageb)

raw Fresh raw milk Fermented milk Boiled milk Condensed milk Milk powder Yoghurt Cheese Butter Cream

67 77 76 39 129 42 44 80 64

39 (58) 17 (22) 49 (64) 20 (51) 31 (24) 19 (45) 5 (11) 1 (1) 38 (59)

porridge 3 (4) 42 (55) 1 (1) 1 (3) 4 (3) 1 (2) 0 (0) 0 (0) 2 (3)

couscous

rice

bread

13 (19) 7(9) 7 (9) 0 (0) 10 (8) 1 (2) 0 (0) 0 (0) 0 (0)

0 (0) 2 (3) 1 (1) 0 (0) 1 (1) 0 (0) 0 (0) 1 (1) 0 (0)

10 (15) 5 (6) 10 (13) 9 (23) 41 (32) 1 (2) 11 (25) 56 (70) 2 (3)

coffee 0 (0) 0 (0) 0 (0) 3 (8) 38 (29) 0 (0) 0 (0) 0 (0) 0 (0)

other 1 (1) 5 (6) 0 (0) 0 (0) 8 (6) 0 (0) 0 (0) 0 (0) 1 (2)

a Difference to 100 per cent: no response. b Consumers (n) were defined as people having consumed a dairy product at least once in the preceding two weeks.

100%

140

90% 80%

100

70%

Personnes (pourcentage)

Personnes

120 80 60 40 20

0

60% 50% 40% 30% 20% 10%

LFRA

LCAI LBOU LCON LPOU YAOU FROM BEUR CREM irrégulier

fréquent

Figure 1. Consumption of milk and dairy products by frequency level.

0%

1 2 3 4

1 2 3 4

1 2 3 4

p<0.001

p<0.001

p<0.001

LCRU

LCAI

LBOU

1 2 3 4

1 2 3 4

1 2 3 4

1 2 3 4

1 2 3 4

1 2 3 4

p<0.001

p=0.054

p=0.003

p=0.018

p=0.186

p<0.001

LCON

LPOU

YAOU

Niveau socio-économique/Produit Laitier fréquent

FROM

BEUR

CREM

irrégulier

Figure 2. Association of socio-economic status of the household and milk-consumption pattern. N=155.

LCRU Lait frais cru, LCAI Lait caillé, LBOU Lait bouillie, LCON Lait concentré, LPOU Lait en poudre, YAOU Yaourt, FROM Fromage, BEUR Beurre, CREM Crème

Discussion The analysis of the consumption of and dairy product was limited to the sample of the case-control study, which does not allow extrapolating these data to the entire population.

Nevertheless, the data on consumption patterns obtained from the questionnaire can give some general ideas about the milk consumption habits in Bamako.

The consumption of dairy products is frequent among the interviewed population. Most people consume some kind of dairy product regularly. There are differences between the different products, which may in some cases be explained by the availability of the product. Locally produced cheese is sold during the rainy season. Cheese sold during dry season is imported, since the low milk yield during that period does not allow local farmers to produce cheese. The product is hence not that widely available and therefore more expensive. Similar constraints may apply for condensed milk and cream.

The importance of dairy products in the local cuisine is clearly demonstrated. Different products are used in traditional local dishes. Fermented milk is especially appreciated for this purpose.

RASPA Vol.3 N 03-4, 2005

“Boiled milk” was translated into the local language “Bambara” as “nônô woulilen”. This term comprises all sorts of heat-treated milk, i.e. milk boiled at home, in collection centres or pasteurised industrially.

The association of consumption habits with socio-economic status (figure 2) is likely to be related to product prices and availability. Traditional products, such as fresh raw milk and fermented milk are mainly consumed by poorer households, more expensive products, such as boiled and condensed milk, yoghurt, cheese, butter and cream are mainly consumed by richer households. Milk powder is widely used and consumed in different forms but there are still more regular consumers in the richer households. The choice of milk power products is directed by their easy storage, low prices in term of equivalent of one litre of milk. The dominance of milk powder products on the “informal” market is the result of high milk demand, low supply of locally produced milk and low price of imported milk.

The reason could also be found in the incapacity of policy makers to set up appropriate milk policy. Two main reasons are given: the huge taxes perceived by the state on milk importation and the strategic and contradictory issue of access to low price milk products by the population in the frame of poverty alleviation. This study suggests interest for developing local products in the strategic point of view.

176

M.W. HETZEL et al.

The associations demonstrated between consumption patterns and sex in “Médina Coura” and “Dialakorodji” may be due to confounders. However, there may be differences in consumption habits or the knowledge on dairy products between the sexes. As it has been shown in table 5, fermented milk is usually consumed in local dishes. Girls may be likely to help working in the household and may therefore know better what kind of milk is used in the dishes. However, this does not explain, why the same associations could not be shown for the other places. There may well be influences on the consumption behaviour which differ between males and females.

The popularity of milk powder may be a result of higher prices and lacking availability of local products. Especially in the dry season, milk yield is low and consumer demands may not be satisfied. Furthermore, heavy contamination of locally produced milk as a result of lack of hygiene in the milk chain as demonstrated by Bonfoh et al. [2], may result in increased use of imported milk powder or of boiled milk in richer households.

Most milk is from cows, as these animals are more frequent and their milk production is higher than the one of small ruminants. Many people did not know from which animals their milk came, which may be due to the age of the participants in the study. In addition, some may have responded wrongly that their milk was from cows, just because cows are the animals primarily associated with milk.

Acknowledgements We would like to thank the study participants, the interviewers and the staff of the health centres and the schools in Bamako for their participation and support. We are grateful to the personnel of the Sahel Institute and the Central Veterinary Laboratory in Bamako. Many thanks to Mitchell Weiss for critical revision of the manuscript.

The study received financial support from the Swiss Tropical Institute, the Swiss National Science Foundation and the Swiss Agency for Development and Co-operation.

Bibliography 1- BONFOH B.; DEM S.; KEITA O.; DELORENZI S.; TRAORE H.; SIMBE C.F.; AFAROUKH O.I.; FARAH Z.; NICOLET J. et ZINSSTAG J., 2003. Assessment of antibiotics residues by microbial inhibitor test in fresh cow milk sold in Bamako (Mali). Milchwissenschaft, 58 (5-6) : 304307.

2- BONFOH B.; WASEM A.; TRAORE A.N.; FANE A.; SPILLMANN H.; SIMBE C.F.; AFAROUKH O.I.; NICOLET J.; FARAH Z. et ZINSSTAG J., 2003.Microbiological quality of cows’ milk taken at different intervals from the udder to the selling point in Bamako (Mali).

Food Control 14 (7) : 495-500.

3- DEBRAH S.; SISSOKO K.; et SOUMARE S., 1995. - Etude économique de la production laitière dans la zone périurbaine de Bamako au Mali. Revue d’Elevage et de Médecine vétérinaire des pays tropicaux 48 (1) : 101-109.

4- FAO, 2002. - FAO Statistical Database. 2003.

5- HETZEL M.W.; BONFOH B.; FARAH Z.; TRAORÉ M.; SIMBE C.F.; ALFAROUKH I.; SCHELLING E.; TANNER M. et ZINSSTAG J., 2004. - Diarrhoea, vomiting and the role of milk consumption: perceived and identified risk in Bamako (Mali). Tropical Medicine and International Health (in press) 6- SISSOKO, K., S. DEBRAH, et SOUMARE S., 1992. Patterns of acquisition and consumption of milk and other dairy products in Bamako, Mali. Dairy marketing in subSaharan Africa. R. F. Brokken and S. Seyoum. Addis Ababa, ILCA (International Livestock Centre for Africa).

7- THE WORLD BANK GROUP, 2003.- Measuring Living Standards: Household Consumption and Wealth Indices Quantitative Techniques for Health Equity Analysis Technical Note #4.

Conclusion The data show clearly the importance of milk and other dairy products for people in Bamako, Mali. Milk is popular and widely appreciated but availability, prices and quality may be major constraints to regular consumption in many households [3]. Development of the milk market should lead to an increasing local production and improved distribution of dairy products. But quality of the products and fair prices have also to be considered. Despite the health risks associated with locally processed milk products (from raw milk or powder milk), consumption is still increasing and need specific guidelines in the milk chain.

²²²

177

RASPA Vol.3 N0 3-4, 2005