静岡県立大学短期大学部
研究紀要第９号
1995年度Production of Traditional Fermented Milk in Kenya (a Review)

257

Production of Traditional Fermented
Milk in Kenya(a Review)

byMATHARA J.M., MIYAMOTO T.,2 KOAZE H.,1KIIYUKIA C., 1 and YONEYA T. 3
1Abstract
Traditional fermented milk production and its consumption in Kenya is considered to be one ofthe oldest cultural and traditional practice among many Kenyans. The fermented soft cheese like
product is preferred for its excellent flavor, delicious taste and health giving properties. The ferm
ented product is produced by local people using locally available materials and ancient methods
unique to the people themselves. Due to the ever growing population, the consumption of the fermented product has gained popularity among non-Kenyans and those Kenyans living in urban areas. The fermented product has also been an excellent source of useful dairy fermentation microorganisms for commercial and industrial purpose. The aim of this review is to give an outline of the production of traditional fermented milk in Kenya and draw an insight to its potential andinvestigate its compositional and microbiological characteristics.

Introduction
It would have been impossible for man to survive without the indigenous fermented foods forMillennia as fermentation are part of nature, they also preserve food, improve digestibility and enrich substrates with essential vitamins, proteins and amino acids. They are responsible for manyof the diverse flavors and textures. Man’s association with fermented milk stretches back thousand of years before Christian era, having its origins before the dawn of civilization. Kenyan tradi
tional fermented milk is one of those products with long history. Fermented milk in Kenya has
been produced and consumed by most of communities in the country, particularly the pastrolists

1. Department of Food Science and Postharvest Technology, Jomo Kenyatta University ofAgriculture andTechnology, P. O. Box 62000, Nairobi Kenya.
2. Faculty of Agriculture, Okayama University, Okayama 700 Japan.
3. Laboratory of Food Science and Technology, University of Shizuoka, Hamamatsu College, Japan.

MATHARA J.M., MIYAMOTO T., KOAZE H., KIIYUKIA C., and YONEYA T.

258

who keep large herds of animals. Kenyans prefer a viscous product, fermented with mesophilic cultures producing diacetyl flavor and little CO2(Wango et al, 1992). Traditionally fermented milk
differs in the type of milk and coagulation method used, and of course, in the species of resid
ent microorganisms. The fact that they are traditionally produced, many fermented milk products
which are only made in extremely restricted areas, and have not had their starter microorganisms
adequately studied, is a course of concern for the manufacture of new fermented milks in the future.

Milk production in Kenya
The total land mass in Kenya is 56.9 million hectares. Ten million hectares of this land is classified as high to medium potential land. About 60％ of this land is devoted to crop and milk production. 42.1 million hectares, 80％ of total land area in Kenya, is classified as having low po
tential and is extensively used for livestock production (Development plan 1994-1996). Dairy far
ming in Kenya is a major pre-occupation of its 25 million people. Types of dairy animals kept
includes European breeds such as Friesian, Jersey, Arshire and Guernsey. Majority of herd reared
comprises of cross breed between the European breeds and local Zebu. Common crosses includ
es Sahiwal and Nandi breed which are reared for milk production. Dairy farming in Kenya is concentrated in Rift Valley Province (Fig. 1). In most districts of Rift Valley, dairy farming is ca
rried out on large farms of over 250 hectares. It is often associated with farming of cereals suc
h as wheat, maize and barley. Average dairy herds on search farms vary in size but it is not less than 50 cows. In other districts, dairy farming is carried out in small farms where it compete
s with growing cash crops such as tea, coffee, and pyrethrum. Expansion of dairy farming in these farms is limited by the size of land.
Kenya produced 1.826 billion tons of milk in 1992. With the milk production growth rate of 2％ per year, she is targeted to produce 1.976 billion tons of milk in 1996. Milk produced is pr
ocessed into a number of products by dairy processing firms. The major milk processing firm in
Kenya is Kenya Cooperative Creameries (K.C.C.). There are other processing firms which inclu
de Daramere Dairies, Brooke side Dairy, Kitida Cooperative among many others.

Traditionally fermented milk in Kenya.
Traditionally fermented milk refers to that milk product which is indigenous to the region of pro
duction and has been developed by the communities living in that region themselves. Traditionally fermented milk has long history and form an integral part of the culture, the word traditional
does not meanancient’. It rather indicates that the product is produced using old age techniq

ues from locally available materials. Although documentary evidence is not available, it appears t
hat preoccupation factors played a role in the emergence of traditional fermented milk in Kenya.
Studies indicates that 53％ of milk produced in cooler Kenyan highlands is consumed as fermen
ted milk

maziwa lala’ (Shalo 1973). Production and consumption of fermented milk is a dairy undertaking in arid and semiarid areas of Kenya.
The major areas where fermented milk is still being produced and consumed include, Narok andProduction of Traditional Fermented Milk in Kenya (a Review)259

Fig. １．MAP OF KENYA
Kanjiado districts by the Maasai community, and Nandi, Elgeyo, and Marakwet districts by theKalenjin community. Other districts include Turkana, Kitui, Machakos, Marsabit and Garissa among others. Consumption of fermented milk in these regions is a cultural habit that has been pra
cticed since time in memorial.

MATHARA J.M., MIYAMOTO T., KOAZE H., KIIYUKIA C., and YONEYA T.

260

Method of traditional fermented milk production in Kenya.
The following description is based on investigations carried out by the authors among the Kalenjin community living in Rift Valley, Kapsabet area indicated on the map (Fig. 1). The communit
y is one of those communities in Kenya who extensively produce and consume the fermented milk product.
The fermented milk product is referred to as mursik in this area by Kalenjin community. It is amajor type of diet whose production and consumption constitutes more than half of the daily food consumption. On average, 500 ml of the product is consumed daily per person. It is very p
opular with adults especially men. It is commonly consumed after meals and sometimes together
with other food preparations such as ugali, a maize meal which is a staple food in Kenya. Theproduct is usually fed to breast feeding mothers and initiates. It is believed that when feedingon this product, one grows stronger and his or her immune system against common diseases isenhanced. Production of this fermented milk product is facilitated by availability of milk produce
d by the pastrolist Kalenjin communities.
A gourd, specifically prepared for preparing mursik is washed with hot water with the aid of cu
red wood stick known as sosiot, obtained from palm branches. The gourd is then left outside for a few hours to dry. When the gourd is dry, it is rubbed inside with burning end of some chopped stick collectively called itoik. This chopped sticks are obtained from special trees namely, chemakltit and sinetwet. They are cut and dried before use.
The rubbing effect makes the charcoal break inside. A specially dried stick called Sosiot obtained frompalm branches is used to break the charcoal to finer particles. The main purposes of using theburnt stick are to improvement of flavor of mursik, pasteurization of the gourd and the coloringof the mursik. The bigger charcoal particles are removed using a special instrument similar to afly whisk. This consists of a tail of a cow fitted with a small stick. Raw milk is then put into
the gourd for 7-10 days. At the end of this period milk will have soured. It is then checked for whey formation. In presence of whey the outer curd is removed and whey drained off. The gourd is then refilled again with fresh milk and ripening continues. The gourd is frequently checked within the first one month for whey forma
tion. In case of any, it is drained off and thegourd refilled with fresh milk. After one month, whey formation stops. Under good produ
ction environmental conditions, i.e. temperature, and good hygiene the mursik can be ripene
d for up to 12 months. This is carried out inthe same gourd at ambient temperatures. Mu
rsik is consumed alone or with other foods li
ke Ugali a major type of food consumed inKenya. A longer fermentation time is preferre
Fig.２. Gourd preparationd due to a notable improvement in products s

Production of Traditional Fermented Milk in Kenya (a Review)

261

ensory characteristics.
Starter characteristics of the traditional
fermented milk productStudies carried out on traditional fer-mented
milk collected from Kanjiado, Narok and Na
kuru district indicated that fermentation is sp
ontaneously carried out by lactic acid bacteria(Miyamoto at al, 1986).
Characteristics of isolated species indicated that Lb.plantarum produced type DL - lactic acid, grows at 15 ℃ and 45 ℃. Two strains of Str. lactis had characteristics which were p
artially similar to those of Str. faecalis. The
strain identified as Str. cremoris differed from typical strain in that it could ferment a w
ide range of carbohydrates. Two strains of L
euc. mesenteroides produced D - lactic acid aFig.３. Serving the fermented milk productnd were positive for dextran formation. In terms of properties of lactic acid bacteria isola Table 1. Distribution of lactic acid bacteria isolat
ed from traditional fermented milk.

ted from the traditional fermented milk, thehighest acidity produced by Lb. plantarum inskim milk containing 0.5％ glucose during
two weeks of incubation was 1.5％ and thatby Lb. curvatus

plantarum

was 1.34％. Some strainsof Lb. plantarum, Lb. casei andLb. curva

tus were found to have relatively high aroma
producing abilities. One strain of Str. lactis
examined, Str. lactis KM, showed greater antimicrobial activity against both S. aureus and B. subtilis (Fig 4). Studies carried out on lactic acid bacteria isolates from traditional fermen
ted milk produced by Maasaiin northern Tanzania indicates that, Lc. lacis ssp. lactis and Lb. confusus has the ability to inhibit growth of Stap. aureus and E. coli (Isono et al,. 1994).
In terms of the proximate composition, unpublished research findings indicate that traditional fer
mented milk from Nandi District has high butter fat content, high protein content and high ash
content than the commercially fermented milk product. Table 3 compares samples obtained fromfermented milk in Nandi district. Samples 02, 03, and 04 were obtained from independently fer
mented product after one, two, and three weeks of incubation at room temperature, respectively.
The studies indicate that the physical nature of the product is similar to that of fresh cheese. That is a product with a soft smooth textured consistency.

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MATHARA J.M., MIYAMOTO T., KOAZE H., KIIYUKIA C., and YONEYA T.

Total plate count results indicate that the numbe
r of microorganisms fall within the range expec
106 -109 per ml.

ted in cultured milk which is

Total solid content is high though no convention
al standardization was done. This can be attribut
ed partly to the treatment procedure of gourd wi
th burnt stick which adds some solids to the product. Protein content is similar to that of full f
at plain yogurt in Japan and slightly lower thanthat of full fat plain yogurt in Europe.
Fat content is relatively higher compared to aver
age fat content of fresh milk which is 3.3 ％.
Ash content is higher for sample 04 as compare
d to the other samples. There is noticeable incre
ase in total plate count from samples 02 to 04.
There is low titratable acidity in sample 02 andhigher in samples 03 and 04.
Fig.４. Effect of Streptococcus lactis MK ag
ainst the growth of Staphylococcus aureus I
AM 1011 in 10％ reconstituted skim milk. (The most powerful means of obtaining useful da MIYAMOTO et al,. 1986)
iry cultures is through screening the microorgani

Conclusion and recommendations

sms from naturally occurring fermentation processes (Dick et al,. 1993).
Fermented milk from Kenya is one of the product which has shown some strains of great indu
strial potential (Morita et al,. 1992).
Table 2. Composition characteristics of traditional fermented milk
Parameter／Sample

020304

Ref. 1

Ref. 2

Total solids, ％

19.03

23.72

26.85

8.0

−Crude ash, ％

0.52

0.63

0.94

0.8

0.8Fat, ％

4.50

3.45

3.30

3.0

3.8

Crude protein, ％

3.37

3.16

3.28

3.2

3.8

Titratable acidity, ％

0.27

1.22

0.90

pH

4.30

4.20

4.50

Total plate count, CFU／g

2.7×107

6.5×1077.2×107

NB: Ref. 1 Full fat plain yogurt in Japan.
Ref. 2 Full fat plain yogurt in Europe.

Production of Traditional Fermented Milk in Kenya (a Review)

Screening of useful dairy fermentati
on cultures from fermented milk fro263Table 3. Sensory description of the traditional ferment
ed milk.

m Kenya, therefore need to be studied.
There are a number of therapeutic an
d nutritional properties associated wit
h fermented milk. This could not be
under-emphasized especially concerni
ng with the health problems related t

SSo cardiovascular disorders, cancer andshort life span among human beings.
The biotechnological potential of trad
itional fermented milk is actually gre
at. Production and consumption of fermented milk product in Kenya form

NB : Samples 02, 03, and 04 were obtained from product fermented for one, two and three wee
ks, respectively.

s a crucial part of diet to many Ken
yans and non Kenyans. There is, therefore, a need to exploit further the health value of this common and traditional product from Kenya.

References:
1. Miyamoto, T. et al. (1986). Identification and properties of lactic acid bacteria

iso-lated fro

m traditional fermented beverages in E. Africa. Japanese Journal ofZootechnical Science, 57(3), 265-276.
2. Shalo, P. L. Hansen, K. K. (1973). Maziwa lala- A Fermented milk. World Animal
Rev., 5, 32-37.
3. Isono, Y., Ishingu, I., Shimizu, S. (1994). Identification and characterization of lactic

acidbacteria isolated from Maasai fermented milk in Northern Tanzania.
Bioscience Biotechnology and Biochemistry, 58 (4), 660-664.
4. Dick, J. C. et al. (1993). Isolation, screening and identification of lactic acid bacte-ria fro

m traditional food fermentation processes and culture collections. Food
Biotechnology, 7 (3), 189-205.
5. Nakamura et el,. (1993). Stability of lactose metabolism transferred into citrate fermenting
Lactococcus lactis by conjugation. Milchwissenschaft, 48 (2), 82-85.
6. Morita et al,. (1991). Intergeneric transfer of lactose fermenting ability toPediococcus acidilactici by conjugation Agric. Biol. Chem., 55 (11), 2871-2873.
7. Wango J., Schulthess, W., Struebi, P. (1992). Flavoring of cultured milk producth fruits available in Kenya. Milchwissenshaft, 47 (1), 27-31.
8. Development plan 1994-1996 Ministry of Planning and Regional Development.
Published by Government Press Kenya.

Mala wit

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MATHARA J.M., MIYAMOTO T., KOAZE H., KIIYUKIA C., and YONEYA T.