AFRIKA FOCUS Vol. 2, Nr. 3 - 4 , 1986 , p p . 2 9 9 - 3 2 4

TRADITIONAL BEERS PROCESSING IN TANZANIA : DEVELOPMENT

NEEDS

B e n d a n t u n g u k a TI ISEKWA Soko ine Un ive rs i t y o f A g r i c u l t u r e , D e p a r t m e n t o f Food Sc ience and Techno logy P.O. Box 3006 , M o r o g o r o , Tanzania P r e s e n t Adress : R.U.G.

F a c u l t y o f A g r i c u l t u r a l Sciences D e p a r t m e n t o f Techno logy , C h e m i s t r y and M ic rob io logy o f Foods C o u p u r e Links 653

9000 GENT

CURRENT RESEARCH INTEREST : I m p r o v e m e n t o f T r a d i t i o n a l Alcohol ic Beverages in Tanzania

SUMMARY

A g e n e r a l a c c o u n t o f t h e s t a t u s o f t h e t r a d i t i o n a l a lcohol ic b e v e r a g e s in Tanzania is p r e s e n t e d w i t h special f o c u s on s o r g h u m b e e r s . The t r a d i t i o n a l p r o c e d u r e used t o p r e p a r e Mtama ( so rghum) b e e r , a p o p u l a r a lcohol ic b e v e r a g e o f Tanzania is d e s c r i b e d . Based on t h e pe rsona l e x p e r i e n c e o f t h e a u t h o r h imse l f and on r e p o r t s in t h e l i t e r a t u r e t h e p r o b l e m areas r e q u i r i n g t e c h n o l o g i c a l i m p r o v e m e n t on th i s b e e r a r e o u t l i n e d . The case f o r i m m e d i a t e r e s e a r c h needs , a imed a t d e v e l o p i n g a commerc ia l l y v iab le Mtama b e e r , is a r g u e d .

KEYWORDS : Mtama b e e r , s o r g h u m b e e r , Tanzan ian b e v e r a g e s t r a d i t i o n a l a lcohol ic b e v e r a g e s

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1.0 INTRODUCTION

T h e r e ex is ts a p r e j u d i c e t h a t many o f t h e t r a d i t i o n a l f o o d s o f d e v e l o p i n g c o u n t r i e s a r e i n f e r i o r in q u a l i t y and n o t w o r t h y o f f u r t h e r d e v e l o p m e n t . The t r a d i t i o n a l b r e w i n g i n d u s t r y o f Tanzania r e p r e s e n t i n g a la rge n u m b e r o f a lcohol ic b e v e r a g e s fa l ls in th i s c a t e g o r y .

A l t h o u g h t h e s e f e r m e n t a t i o n s a r e cal led b e e r s , t h e y a r e n o t real ly " b e e r s " in t h e sense o f t h e W e s t e r n d e f i n i t i o n . These b e e r s , l ike m o s t o t h e r A f r i c a n b e e r s , a r e c h a r a c t e r i z e d by be ing o p a q u e l iquids o r s e m i - s o l i d s , w i t h v a r y i n g alcohol c o n t e n t s , and by c o n t a i n i n g h igh p e r c e n t a g e s o f solids and m i c r o o r g a n i s m s . They a r e a c i d - f e r m e n t e d b e v e r a g e s p r e p a r e d mainly f r o m cerea ls t r a d i t i o n a l l y g r o w n in Tanzania , n o t a b l y s o r g h u m , mi l l e t , and maize .

These b e e r s a r e b o t h a f o o d i t e m and b e v e r a g e , and play an i m p o r t a n t r o l e in t h e daily and t r i b a l l i f e o f t h e Tanzanians . All o v e r t h e c o u n t r y , b e e r - d r i n k i n g - c e r e m o n i e s a r e he ld a t t h e schools o f i n i t i a t i ons f o r boys and g i r ls , a t w e d d i n g s , f u n e r a l s , and a t communa l a c t i v i t i e s such as f a r m and c o n s t r u c t i o n w o r k s . Beer d r i n k s , t o o , a re o f t e n he ld as a means o f s e t t l i n g q u a r r e l s . In m o d e r n t i m e s , t h e s e b e e r s have e n t e r e d t h e c o m m e r c e . B o t h in t h e vi l lages and t o w n s h i p s many p e o p l e e a r n t h e i r l iving t h r o u g h sel l ing b e e r and t h e local g o v e r n m e n t s b e n e f i t f r o m levies on b e e r sales.

The W e s t e r n t y p e b e e r p r o d u c e d in Tanzania c a n n o t m e e t t h e d e m a n d o f even t h e f e w p o p u l a r c o n s u m e r s and is sold a t a c u t - t h r o a t p r i c e wh ich t h e m a j o r i t y o f t h e p o p u l a t i o n c a n n o t a f f o r d . A l t h o u g h t h e Tanzan ian t r a d i t i o n a l b e v e r a g e s have b e e n c o n s u m e d f o r ages, t h e r e has n o t b e e n any ser ious s c i e n t i f i c i n v e s t i g a t i o n t o es tab l i sh t h e i r n a t u r e , and e x p l o r e t h e poss ib i l i t y f o r f u r t h e r d e v e l o p m e n t . A p a r t f r o m "Ch ibuku" b e e r , t h e only " i n d u s t r i a l i s e d " t r a d i t i o n a l b e e r (made using i m p o r t e d t e c h n o l o g y ) , t h e p r o d u c t i o n o f t h e rema in ing m a j o r i t y o f t h e s e b e e r s have n o t a d v a n c e d b e y o n d t h e c o t t a g e scale. The n e e d t o d e v e l o p t h e s e t r a d i t i o n a l t e c h n o l o g i e s on an i ndus t r i a l scale, especial ly t h e u t i l i s a t i o n

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o f s o r g h u m as a s t a p l e f o o d c o m m o d i t y / b e v e r a g e base, has b e e n m u c h e m p h a s i z e d by severa l w o r k e r s (Hesselt ine, 1 9 7 9 ; Lukoo e t . al . , 1981 ; Kayumbo, 1985) . The Tanzanian po l icy makers t o o have cal led u p o n local s c i e n t i s t s i n t o he lp ing peasants i m p r o v e t h e i r s t a n d a r d s o f l iving by d e v e l o p i n g t h e e x i s t i n g t e c h n o l o g i e s , especial ly t h o s e r e q u i r i n g h igh scale local i n p u t s (Lukoo e t . al. , 1981 ; Kayumbo, 1985) .

In v iew o f t h e s e p e r s p e c t i v e s th i s p a p e r p r e s e n t s : a. an a c c o u n t o f t h e m a j o r t r a d i t i o n a l a lcohol ic b e v e r a g e s o f

Tanzania b, an o u t l i n e o f a l a b o r a t o r y - s c a l e p r e p a r a t i o n , and analysis

o f "Mtama" b e e r , a p o p u l a r t r a d i t i o n a l s o r g h u m b e v e r a g e , as a s t a r t i n g p o i n t f o r f u r t h e r a c t i v i t y in t h i s f i e l d , and

c a n i d e n t i f i c a t i o n o f c r i t i c a l areas f o r t e c h n o l o g i c a l d e v e l o p m e n t a l w o r k in t h e near f u t u r e .

I n f o r m a t i o n in r e s p e c t o f t h e t r a d i t i o n a l b r e w i n g p r o c e s s d iscussed in th i s a r t i c l e has b e e n g a t h e r e d by i n t e r v i e w i n g e x p e r i e n c e d local b r e w e r s ( b o t h h o m e - s c a l e and c o m m e r c i a l b r e w e r s ) in Tanzania , and f r o m t h e persona l e x p e r i e n c e o f t h e a u t h o r h imse l f .

2.0 THE MAJOR TRADITIONAL ALCOHOLIC. BEVERAGES OF TANZANIA

The t r a d i t i o n a l a lcohol ic b e v e r a g e s o f Tanzania a r e co l l ec t i ve l y r e f e r r e d t o as " p o m b e za k i e n y e j i " as o p p o s e d t o " p o m b e za k i z u n g u " , t h e W e s t e r n t y p e b e e r s . These t r a d i t i o n a l b e e r s a r e cal led "Mapuya" in t h e Sukumaland , a t y p i c a l r u r a l a rea , w h e r e t h e y a r e he ld in h igh e s t e e m , whi le in t h e u r b a n i s e d areas t h e y a r e known as " M a t a p u t a p u " - a d i s c r e d i t a b l e name imply ing " tower b r e e d " .

I t is n o t poss ib le t o s t a t e p rec i se l y t h e e x a c t n u m b e r o f t h e s e b e v e r a g e s in c i r c u l a t i o n a t p r e s e n t . D e p e n d i n g on t h e i n g r e d i e n t s , p r o c e s s i n g and f ina l c h a r a c t e r i s t i c s , severa l names a r e g iven t o t h e m in d i f f e r e n t t r i b a l d i a l e c t s . Also, w i t h m o r e t h a n 120 A d m i n i s t r a t i v e D i s t r i c t s , one f i n d s a t least one t y p i c a l b e v e r a g e w i t h i ts d i s t i n c t f l a v o u r / t e x t u r e

G e o g r a p h i c a l Zones (and relevant regions)

Urban C e n t r e s tion C e n t r e s .

The Capital and All Regional A d m i n i s t r a -

T a n g a , Dar-es-Salaam, P w a m and Mtwara C o a s t a l Belt r e g i o n s . S u b - C o a s t a l Zone : mainly M o r o g o r o region. N o r t h e r n Zone : m a i n l y Kilimanjaro and Arusha r e g i o n s . C e n t r a l Zone : D o d o m a , Singida and part of the Shinyanga and T a b o r a r e g i o n s . Lake Zone : Mara, Mwanza and Kagera r e g i o n s . W e s t e r n Zone : Kigoma and the main parts of Tabora and S h i n y a n g a r e g i o n s . S o u t h e r n Zone : R u v u m a and Lindi r e g i o n s . S o u t h - W e s t e r n Zone : Iringa, Rukwa and Mbeya r e g i o n s .

T a b l e 1. - The Ma3or T r a d i t i o n a l Alcoholic B e v e r a g e s of T a n z a n i a .

Name Symbol Beverage Base

Mtama Ma Sorghum, m a i z e bran

Indimasi In Sorghum

Kayoga Ky Sorghum

Impeke Im Sorghum

Kangala Kl Sorghum, m a i z e b r a n , s u g a r

Mbege Mb Millet, b a n a n a juice

Mtukulu Mk Millet

Komoni Ko Maize, millet

Kimpumu Kp Millet

C h i b u k u C Sorghum

Kindi Kd Maize

Gwagwa G Banana juice, sorghum

Rubisi R B a n a n a juice, sorghum

Ulaka Uk C a s h e w apple juice

M n a n a s i Mn P i n e a p p l e juice

D e n g e l u w a D Sugar cane sap

Te mbo T C o c o n u t tree sap

Ulanzi Uz Bamboo sap

W a n z u k i W Honey

Kabungusi Ks Tea, C o f f e e b r e w s

Njimbo N Honey, M o l a s s e s

Symbols refer to F i g u r e 1.

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a t t r i b u t e s in e v e r y D i s t r i c t . The m o s t p o p u l a r , t r a d i t i o n a l a lcohol ic b e v e r a g e s o f Tanzania a r e l i s t e d in Table 1; and t h e i r g e o g r a p h i c a l d i s t r i b u t i o n i l l u s t r a t e d in F ig . 1.

I t is a p p a r e n t f r o m Table 1, t h a t most, o f t h e s e b e v e r a g e s a re based on cerea ls , p a r t i c u l a r l y s o r g h u m . This is a t t r i b u t a b l e t o t h e e x t e n s i v e c u l t i v a t i o n o f th is d r o u g h t -r e s i s t a n t c r o p , p r a c t i c a l l y u n d e r e v e r y e x i s t i n g c l imat ic e n v i r o n m e n t in Tanzania .

The d i s t r i b u t i o n o f o t h e r b e v e r a g e s in r u r a l areas c o r r e s p o n d s t o t h e avai lab i l i ty o f t h e c r o p u p o n w h i c h t h e b e v e r a g e is based . Thus, Rubisi o r Gwagwa (banana wine) b e v e r a g e s a r e c o n f i n e d t o t h e reg ions w e s t o f t h e Lake V i c t o r i a w h e r e banana is a s t a p l e . Similar ly , Mbege and Kindt a re p o p u l a r in t h e n o r t h e r n and s o u t h - w e s t e r n Zones w h e r e banana and ma ize r e s p e c t i v e l y a r e s tap les . Utaka, a wine f r o m cashew f r u i t j u i c e f e r m e n t a t i o n is f o u n d exclus ive ly on t h e Coastal Be l t w h e r e cashew is an i m p o r t a n t c r o p . I n U rban C e n t r e s , h o w e v e r , severa l b e v e r a g e s may be f o u n d d e p e n d i n g on t h e raw m a t e r i a l avai lab i l i ty and r e l a t i v e d e m a n d s imposed by t h e m ixed t r i b a l c o m m u n i t y .

3.0 THE PROCESSING OF TANZANIAN SORGHUM BEVERAGES

3.1 Some A s p e c t s o f S o r g h u m C u l t i v a t i o n

S o r g h u m is c u l t i v a t e d as t h e m a j o r c r o p in some reg ions o f Tanzania , w h e r e i t c o n s t i t u t e s t h e s t a p l e d i e t in t h e f o r m o f a s t i f f p o r r i d g e cal led "uga l i " . I n m o s t o t h e r areas i t serves as a " b u f f e r " c r o p in p e r i o d s o f d r o u g h t w h i c h t h e m a j o r cerea ls (maize , r ice ) c o u l d n o t e n d u r e . Realising i ts p o t e n t i a l , t h e Tanzan ian g o v e r n m e n t has i n s t i t u t e d a p r o m o t i o n a l campa ign f o r t h e c u l t i v a t i o n o f s o r g h u m on a nat iona l scale, and p a r t i c u l a r l y in t h e a r id reg ions (Mosha e t . al . , 1977) . (Ex tens i ve r e s e a r c h is be ing c o n d u c t e d on t h e a g r o n o m i c a s p e c t s o f th is c r o p a t t h e va r ious E x p e r i m e n t a l S t a t i o n s in t h e c o u n t r y . )

- 30 e *

The p r o d u c t i o n t r e n d o f s o r g h u m in Tanzania as pub l i shed by FAO is p r e s e n t e d in Table 2. However , Mosha and L o r r i (1978) r e p o r t e d even h i g h e r p r o d u c t i o n f i g u r e s f o r s o r g h u m - 3 1 8 ( 1 9 7 4 / 7 5 ) , 438 ( 7 5 / 7 6 ) , and 517 ( 7 6 / 7 7 ) t h o u s a n d s o f m e t r i c t o n s .

Table 2. Annual Production of Sorghum and Millet in Tanzania, 1973-1976 and 1980-1983 ('000 metric tons ; FAO, 1983)

1973 1974 1975 1976 1 1980 1981 1982 1983 2 1984 2 1985 2

Sorghum 248 128 180F 245 220F 220F 220F 793 492 724

Millet 171 63 120F 129 160F 140F 150F 206 267 300

Total 419 191 300 374 380 360 370 999 759 1024

mean for 1974-1976 F = FAO estimate

2 FAO, 1986

3.2 The T r a d i t i o n a l B rewing Techn iques

3.2.1 P o s t - h a r v e s t Handl ing P r a c t i c e s :

S o r g h u m is an annual c r o p r e q u i r i n g f i v e t o six m o n t h s t o m a t u r e ; h o w e v e r , c e r t a i n c u l t i v a r s (Se rena and Lulu) have a s h o r t e r cyc le . Severa l v a r i e t i e s a r e t r a d i t i o n a l l y g r o w n , w i t h b r o w n , w h i t e and m i x e d c o l o u r g r a i n v a r i e t i e s be ing p o p u l a r . These p o p u l a r v a r i e t i e s e x h i b i t b o t h o p e n and c losed panic le s t r u c t u r e s . An e x a m p l e o f a c losed panic le s t r u c t u r e g r o w n in Tanzania is d e p i c t e d in F i g u r e 2. W h e n t h e g r a i n is f u l l y r i p e n e d t h e panic les a r e h a r v e s t e d us ing k i t c h e n knives. T rad i t i ona l l y , t h e y a r e p i led in heaps o v e r t h e k i t c h e n r o o f w h e r e t h e y a r e l e f t t o d r y all t h e y e a r a r o u n d by t h e k i t c h e n smoke (Fig. 3) . W h e n t h e y a r e s u f f i c i e n t l y d r y , t h e heaps a r e c o v e r e d w i t h d r y grass f o r p r o t e c t i o n f r o m ra in . A l t e r n a t i v e l y , s o r g h u m panicles may b e s t o r e d in a "K ihenge" , a s t r u c t u r e specia l ly c o n s t r u c t e d f o r t h i s p u r p o s e (F ig .4) .

T r a d i t i o n a l Beers Processing in Africa.

F i g u r e 2 - Immature sorghum growing in the field (Courtesy Department of Crop Science, Sokoine U n i v e r s i t y of A g r i c u l t u r e , M o r o g o r o , T a n z a n i a ) .

T r a d i t i o n a l Beers Processing in T a n z a n i a .

F i g u r e 3 - T r a d i t i o n a l storage and threshing techniques ; : sorghum panicles piled on the roof of a

gr a s s thatched h o u s e (kitchen) ; %2 : threshing dry sorghum panicles by beating

on the floor with an oar - s h a p e d wooden b a t o n .

Syt '**fil'' !(' > j \ tx/jy' g r a s s thatched roof

w a l l (wooden b a t o n s plastered w i t h mud or cow-dung )

metal s l e e v e s to ke e p out rats

T r a d i t i o n a l Beers Processing in Ta n z a n i a .

F i g u r e 4 - Diagram of a typical Kihenge for Grain Storage (adapted from a village care Handbook, Werner 1985)

SORGHUM

D r y - C l e a n i n g (to remove impurities)

Aqueous Wood Ash

suspension-

Water

Steeping (1 2-18 hours)

)

W a s h i n g

Ambient G e r m i n a t i o n (15-40C)(4-5 d a y s )

Steep liquor (red liquid)

Wash water

"GREEN" SORGHUM MALT t

S u n - D r y i n g (20-40C)

Screening and C l e a n i n g (to remove r o o t l e t s & s h o o t l e t s )

DRY SORGHUM MALT

Fig. 5 : Malting of Sorghum

O p t i o n a l s tarch a d j u n c t s

CASSAVA (fermented or d r i e d )

M I L L E T ( g r a m or malt) o r MAIZE (bran or g r i t s )

B O I L I N G WATER

CLEANED SORGHUM MALT

Mixing

Grinding

Flour

MTAMA DOUGH

Ambient C o o l i n g

UMWAMBIRO (starter)

POTABLE WATER4

Mixing

UMUTOBE

F e r m e n t i n g at 2 0 - 3 0 C for 24h

Fermenting at 20-30C for 36 to 48 h

F e r m e n t i n g at 2 0 - 3 0 C for more than 48h

UMUBIRA IHIRA UMUCHE

Fig. 6. T r a d i t i o n a l Preparation of Mtama Beer

Occasionally s o r g h u m panicles a r e also h e a p e d on w o o d e n p l a t f o r m s and c o v e r e d w i t h d r y grass .

The d r y s o r g h u m panic les a r e t h r e s h e d i m m e d i a t e l y b e f o r e use by b e a t i n g t h e m on t h e f l o o r w i t h w o o d e n b a t o n s (F ig .3) . I f small q u a n t i t i e s a r e r e q u i r e d t h e panic les a r e p o u n d e d in a w o o d e n m o r t a r and p e s t l e .

3.2.2. P r e p a r a t i o n o f S o r g h u m Malt :

Resul ts o f o u r s u r v e y i n d i c a t e t h a t t h e r e d and m i x e d v a r i e t i e s o f S o r g h u m b ico lou r , Moench a r e t h e m o s t p o p u l a r and p r e f e r r e d s t a r t i n g m a t e r i a l f o r t h e t r a d i t i o n a l s o r g h u m b e e r s o f Tanzania , p a r t i c u l a r l y in t h e Lake, C e n t r a l and Coastal z o n e s .

The m a l t i n g p r o c e s s o u t l i n e d in F ig . 5 is c o m m o n t o all t y p e s o f s o r g h u m b e v e r a g e s . I n t h e m a l t i n g p r o c e s s f o r Mtama b e e r s o r g h u m gra ins a r e soaked in w a t e r w i t h o r w i t h o u t w o o d ash, f o r one day b e f o r e b e i n g g e r m i n a t e d ; t h e s t e e p e d gra ins a r e w a s h e d , d r a i n e d and s p r e a d on and c o v e r e d w i t h p l a n t leaves o r sisal sackings. A similar t e c h n i q u e is used in Togo, Rwanda, B u r u n d i and Uganda. G e r m i n a t i o n , wh ich s t a r t s w i t h i n 24h a f t e r s t e e p i n g , is a l lowed t o c o n t i n u e f o r a p e r i o d o f 4 - 6 days. The l e n g t h o f t h e r a d i c l e is used t o j u d g e t h e s u f f i c i e n c y o f g e r m i n a t i o n ( N t i r u b a h a m w e , 1985 ; Personal Comm.) . Some b r e w e r s p r e f e r t h e d a r k c o l o u r e d s p r o u t s t h a t f ina l l y g ive g o o d q u a l i t y ma l ts . The g e r m i n a t i o n is usually c o m p l e t e a f t e r a p e r i o d o f f o u r days. A f t e r g e r m i n a t i o n t h e " g r e e n " m a l t is sun d r i e d in t h i n layers (usually one o r t w o days) . The d r y m a l t is t h e n r u b b e d on t h e g r o u n d b e t w e e n f e e t o r l i ght ly p o u n d e d using a w o o d e n m o r t a r and p e s t l e t o r e m o v e r o o t l e t s and s h o o t l e t s . The d r y m a l t can b e s t o r e d f o r a p e r i o d o f u p t o f o u r weeks b e f o r e f u r t h e r use.

3.2.3. P r e p a r a t i o n o f Mtama b e e r :

The p r e p a r a t i o n o f Mtama b e e r f r o m s o r g h u m m a l t is p r e s e n t e d in F ig . 6. T rad i t i ona l l y , mi l l ing is p e r f o r m e d on a

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g r i n d i n g s t o n e o r by p o u n d i n g using a m o r t a r and p e s t l e . W h e n e v e r s t a r c h a d j u n c t s (maize , mi l le t and m o r e f r e q u e n t l y f e r m e n t e d cassava) a r e i n c o r p o r a t e d , t h e y a re m ixed t o g e t h e r w i t h t h e s o r g h u m m a l t and coarse ly g r o u n d i n t o a f l o u r .

The e a r t h e n p o t s used f o r b r e w i n g a r e usual ly h e a t e d w i t h a p r o b a b l e i n t e n t i o n t o " s t e r i l i z e " t h e m ( f i g . 7 ) . The Mtama b e e r d o u g h is p r e p a r e d by a d d i n g bo i l ing w a t e r t o t h e f l o u r m i x t u r e and w o r k i n g o u t i n t o t h i c k c o n s i s t e n c y . The d o u g h is l e f t t o cool t o r o o m t e m p e r a t u r e and t h e n d i l u t e d w i t h w a t e r t o f o r m a suspens ion ca l led U m u t o h e ( t h e p r o p o r t i o n o f w a t e r d e t e r m i n e d f r o m e x p e r i e n c e is usually 1:4). To a c t i v a t e f e r m e n t a t i o n some b r e w e r s a d d a s t a r t e r cal led U m w a m b i r o ( d r i e d p o w d e r o b t a i n e d f r o m an o v e r f e r m e n t e d b a t c h ) t o U m u t o b e . I t is now l e f t t o f e r m e n t in e a r t h e n p o t s ( f i g . 8 ) o r meta l i c c o n t a i n e r s as r e q u i r e d . L i g h t f i r e may be made near t o o r a r o u n d t h e f e r m e n t a t i o n c o n t a i n e r s t o increase t h e t e m p e r a t u r e and s p e e d u p t h e p r o c e s s . F e r m e n t a t i o n can be a r r e s t e d a t severa l s tages d e p e n d i n g on t h e a lcohol s t r e n g t h r e q u i r e d . Thus, t h r e e f e r m e n t a t i o n s tages a r e d i s t i n g u i s h a b l e : a t 24h , Umub i ra ; a t 3 6 h , I h i ra and f i na l l y a f t e r 48h Umuche is o b t a i n e d .

S t r o n g e r b e e r s ( I n t u r i l e ) a r e p r o d u c e d by a d d i n g s y r u p s (usually s u c r o s e o r honey ) t o t h e f e r m e n t i n g m i x t u r e a f t e r 24 o r 3 6 h , and c o n t i n u i n g f e r m e n t a t i o n f o r a f u r t h e r p e r i o d o f 1 -3 days. A t any s t a g e o f t h e a b o v e f e r m e n t a t i o n t h e u n f i l t e r e d b e v e r a g e can be c o n s u m e d s t r a i g h t a w a y . T r a d i t i o n a l l y , calabash scoops , g rass s t r a w ( f o r suck ing f r o m t h e b r e w i n g p o t ) o r glasses a r e used f o r se rv ing t h e s t r a i n e d b e e r ( f i g . 9 ) . W h e n h o r n e - b r e w e d , t h e q u a n t i t y is usually 1 0 -100 l i t r e s ( f o r special occasions o r f ami l y c o n s u m p t i o n ) . As a c o t t a g e i n d u s t r y u p t o 600 l i t r e s c o u l d b e p r o d u c e d in a b a t c h .

3.3 The L a b o r a t o r y - s c a l e p r e p a r a t i o n o f Mtama b e e r

S o r g h u m s samples w e r e p r o c u r e d f r o m Kagera Region o f

T r a d i t i o n a l Beers Processing in A f r i c a .

F i g u r e 9 -A s p e c i a l l y woven s i e v e used for straining sorghum beer (made from flexible thin sticks and g r a s s ) . (photo : P. Van Damme)

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Tanzania, and t h e G h e n t Grain Termina l , G h e n t , Belg ium. The

samples w e r e c l e a n e d , s t e e p e d in ash suspens ion , g e r m i n a t e d

u n d e r c o n t r o l l e d c o n d i t i o n s , and f ina l l y d r y - m i l l e d (0 .8mm

mesh sieve) t o p r o d u c e t h e s o r g h u m mal ts .

The p r o c e d u r e f o l l o w e d in p r e p a r i n g t h e b e e r was essent ia l ly t h e same as t h a t used t r a d i t i o n a l l y ( s e c t i o n 3.2.3.) w i t h f e w m o d i f i c a t i o n s . To a c t i v a t e f e r m e n t a t i o n p i t c h i n g was p e r f o r m e d using a t r a d i t i o n a l s t a r t e r c u l t u r e . F e r m e n t a t i o n was c a r r i e d o u t a t a c o n s t a n t t e m p e r a t u r e o f 30 C.

Mtama b e e r was chosen f o r l a b o r a t o r y w o r k since i t is t h e

m o s t r e p r e s e n t a t i v e o f t h e d i f f e r e n t s o r g h u m b e e r s . Also, is

is t h e m o s t p o p u l a r s o r g h u m b e v e r a g e w i t h a b r o a d c o u n t r y

w i d e d i s t r i b u t i o n .

3 . 3 . 1 . The analysis :

The analyt ica l r e s u l t o f a t y p i c a l sample ( a f t e r s t r a i n i n g ) is

p r e s e n t e d in Table 3.

Table 3. Analytical Parameters of a Laboratory-scale Mtama Beer Sample (Ihira)

Parameter Result Reference

Total solids (%, w/v) 1.75 Pearson (1970) Specific gravity (pycnometer) 1.00 Pearson (1970) Alcohol content (%, w/v) 5.52 Pearson (1970) Acidity (% w/v, as lactic and acetic acids) 0.45 Pearson (1970) pH 3.8 Pearson (1970)

The sensory qua l i t i es (genera l a p p e a r a n c e , f l a v o u r and m o u t h f e e l ) o f t h e l a b o r a t o r y Mtama b e e r samples w e r e similar t o Ind imas i o r Mtama b e e r p r o d u c e d u n d e r t r a d i t i o n a l c o n d i t i o n s (sensory e v a l u a t i o n c o n d u c t e d w i t h 15 Tanzan ian c o n s u m e r s ) . F e r m e n t a t i o n a t c o n s t a n t e l e v a t e d t e m p e r a t u r e

315 -

r e s u l t e d in r e d u c e d t i m e f o r I h i r a p r o d u c t i o n . The analyt ica l r e s u l t , p a r t i c u l a r y t h e pH and s p e c i f i c g r a v i t y , c o m p a r e s v e r y well w i t h t h o s e r e p o r t e d f o r S o u t h A f r i c a n s o r g h u m b e e r s (Novel l ie , 1976) . Also, r e p o r t s on o t h e r s o r g h u m - b a s e d A f r i c a n b e e r s such as t h e N iger ian B u r u k u t u (Faparus , 1970) and t h e Sudanese Merissa (D i rar , 1978) i n d i c a t e a close r e s e m b l a n c e t o t h e Tanzanian s o r g h u m b e e r s in t e r m s o f t h e g e n e r a l p r o c e s s i n g p r o c e d u r e , p r o d u c t a p p e a r a n c e and g e n e r a l t e x t u r a l c h a r a c t e r i s t i c s . Overa l l , t h e b e e r o f f e r s a p r o m i s i n g s c o p e f o r f u r t h e r s t u d i e s in th i s f i e l d .

4.0 TECHNOLOGICAL DEVELOPMENT OF SORGHUM 8EVERAGES

I t is a p p a r e n t t h a t t h e n e a r - f u t u r e t e c h n o l o g i c a l d e v e l o p m e n t a c t i v i t y in th is f i e l d shou ld be c e n t e r e d a r o u n d t h e f o l l o w i n g c r i t i c a l areas :

a. Raw Mate r ia l Qua l i ty A s p e c t s

b. P rocess O p t i m i z a t i o n and c o n t r o l c. P r o d u c t Qua l i ty and S h e l f - l i f e A s p e c t s d . Economic A s p e c t s

This a c t i v i t y shou ld be i n t e g r a t e d in such m a n n e r as t o i n v e s t i g a t e , in t o t a l i t y , t h e c o m m e r c i a l v i a b i l i t y o f p r o d u c i n g an a lcohol ic s o r g h u m b e v e r a g e o f u n i f o r m q u a l i t y c h a r a c t e r i s t i c s , in a t y p i c a l m i n i - b r e w e r y in t h e r u r a l Tanzanian e n v i r o n m e n t .

4.1 Raw Mater ia l Qua l i ty A s p e c t s

T r a d i t i o n a l l y t h e d i f f e r e n t v a r i e t i e s o f s o r g h u m a r e used i nd i sc r im ina te l y d e p e n d i n g on avai l ib i l i ty , w i t h o u t any r e f e r e n c e t o t h e i r b r e w i n g qua l i t i es . Thus, Novel l ie (1962 ; 1982) i d e n t i f i e d c e r t a i n i m p o r t a n t b r e w i n g c h a r a c t e r i s t i c s t h a t r e q u i r e special a t t e n t i o n ; un l ike b a r l e y m a l t , t h e d i a s t a t i c ( e n z y m e ) a c t i v i t y o f s o r g h u m m a l t is g e n e r a l y low, whi le t h e h igh n i t r o g e n c o n t e n t o f t h e m a l t does n o t cause any d i f f i c u l t y in b r e w i n g . The d i a s t a t i c a c t i v i t y was f o u n d t o v a r y among d i f f e r e n t v a r i e t i e s , and also i n f l u e n c e d by t h e c u l t i v a t i n g season, and level o f m a t u r i t y o f t h e g r a i n (Novel l ie, 1962b ) .

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Da iber (1975) e s t a b l i s h e d t h a t t h e v a r i e t a l v a r i a t i o n s c o u l d b e la rge ly a t t r i b u t e d t o t h e t a n n i n c o n t e n t s , t h e tann ins having an i n h i b i t o r y a c t i o n on t h e e n z y m e s y s t e m usually a c t i v e d u r i n g mashing f o r w o r t p r o d u c t i o n . Unless t r e a t e d , some h i g h - t a n n i n s o r g h u m c u l t i v a r s a r e t o t a l l y u n s u i t a b l e f o r c o m m e r c i a l b r e w i n g . However , in t r a d i t i o n a l p r a c t i c e , the* h i g h - t a n n i n v a r i e t i e s ( t h e r e d and m ixed ones) a r e t h e m o s t p o p u l a r f o r b r e w i n g s o r g h u m b e v e r a g e s .

Possib i l i t ies f o r i m p r o v i n g t h e q u a l i t y o f h i g h - t a n n i n s o r g h u m

e x i s t .

The p r o c e s s o f r e m o v a l / i n a c t i v a t i o n o f t a n n i n s in f o o d s is

g e n e r a l l y r e f e r r e d t o as d e t o x i f i c a t i o n s ince t h e s e

p r i n c i p l e s , a t h igh levels, have a d e l e t e r i o u s e f f e c t on t h e

m e t a b o l i s m o f h u m a n and animal s y s t e m s .

The chemica l d e t o x i f i c a t i o n o f h i g h - t a n n i n s o r g h u m s had b e e n s u c c e s f u l l y a c c o m p l i s h e d in S o u t h A f r i c a ; use o f f o r m a l d e h y d e r e d u c e d t h e t a n n i n c o n t e n t by 997., t h e r e b y i m p r o v i n g t h e b r e w i n g q u a l i t y t o a g r e a t e x t e n t . T r a d i t i o n a l l y , c o m p a r a b l e b r e w i n g q u a l i t y is a c h i e v e d in r u r a l a reas , especia l ly in Rwanda and B u r u n d i , by s t e e p i n g t h e g r a i n in w o o d ash suspens ion . However , t h e a r g u m e n t p u t f o r w a r d by t h e t r a d i t i o n a l s o c i e t y f o r s t e e p i n g in t h e w o o d ash suspens ion is n o t d e t o x i f i c a t i o n b u t t h e d e v e l o p m e n t o f a p p e a l i n g s e n s o r y q u a l i t y (da rk ish matt , c r e a m - c o l o u r e d b e e r w i t h a b s e n c e o f a s t r i n g e n t t a s t e ) t h a t r e s u l t s f r o m such t r e a t m e n t . I n t h e i r i n v e s t i g a t i o n s on Tanzan ian s o r g h u m c u l t i v a r s (Lu lu , Mbangara and Se rena ) Muindi e t at. (1981) r e p o r t e d a 57% r e d u c t i o n in t a n n i n c o n t e n t on t r e a t m e n t o f s o r g h u m w i t h a locally avai lable c a r b o n a t e m i n e r a l , Magadi soda (sod ium s e s q u i c a r b o n a t e , Na^O^.NaHCO^.Z^O).

4.2 P rocess O p t i m i z a t i o n a n d C o n t r o l

A u n i f o r m q u a l i t y raw m a t e r i a l w i t h d e f i n i t e q u a l i t y

c h a r a c t e r i s t i c s is t h e p r e - r e q u i s i t e f o r success in any

c o m m e r c i a l v e n t u r e . The o p t i m i z a t i o n o f t h e p r o c e s s i n g

c o n d i t i o n s , and s u c c e s s f u l p r o c e s s c o n t r o l , w o u l d assure t h e

- 317 -

e v e n t u a l m a n u f a c t u r e o f a u n i f o r m p r o d u c t w i t h h igh q u a l i t y . Many o f t h e p r a c t i c e s t h a t a r e b l i n d - f o l d e d l y f o l l o w e d in t h e t r a d i t i o n a l s o r g h u m b r e w i n g p r o c e d u r e m u s t be g iven u p a l t o g e t h e r i f t h i s be e v e r u p g r a d e d t o a commerc ia l l y v iab le i n d u s t r y . F o r i n s t a n c e , r e s u l t s f r o m o u r l a b o r a t o r y s t u d i e s i n d i c a t e t h a t t h e t r a d i t i o n a l mashing p r o c e s s r e s u l t s in t h e c o n v e r s i o n o f only 107. o f t h e t o t a l avai lable c a r b o h y d r a t e s i n t o r e d u c i n g sugars . Some o f t h e u n c o n v e r t e d s t a r c h is slowly c o n v e r t e d t o f e r m e n t a b l e sugars in t h e c o u r s e o f f e r m e n t a t i o n . However , a l a r g e r p a r t o f c a r b o h y d r a t e s a p p e a r in t h e b e e r and in t h e w a s t e a f t e r s t r a i n i n g . The t r a d i t i o n a l f e r m e n t a t i o n is c a r r i e d o u t b y t h e n a t u r a l (mixed) f l o r a p r e s e n t in t h e e n v i r o n m e n t and a t a m b i e n t t e m p e r a t u r e s . I n a s t u d y o f t h e m i c r o b i o l o g y o f s o r g h u m b e e r s Van d e r W a l t (1956) i d e n t i f i e d o v e r one h u n d r e d species o f b a c t e r i a and severa l y e a s t s t r a i n s in t h e f e r m e n t . This f i n d i n g a lone emphas i zes t h e m a g n i t u d e o f t h e cha l lenge e n c o u n t e r e d in th i s f i e l d .

4.3 P r o d u c t Qua l i ty and S h e l f - l i f e A s p e c t s

F o r success fu l m a r k e t i n g a c o n s i s t e n t l y h igh q u a l i t y p r o d u c t is essent ia l . Lack o f s t a n d a r d i z a t i o n o f i n g r e d i e n t s and absence o f any f o r m o f p r o c e s s c o n t r o l , l ead ing t o v e r y h igh day t o t day f l u c t u a t i o n s in p r o d u c t q u a l i t y , has b e e n s t u d i e d among t h e t r i b a l (commerc ia l ) b r e w e r s o f S o u t h A f r i c a (Novel l ie , 1976) . This lack o f s c i e n t i f i c basis may e v e n lead t o d i s a s t r o u s c o n s e q u e n c e s ; f o r i n s t a n c e , levels o f u p t o 4 . 6 m g / l i t r e o f z e a r a l e n o n e , an e s t r o g e n i c m y c o t o x i n (Mi rocha e t . al. , 1971 ; S h e r w o o d and P e b e r d y , 1974) , has b e e n r e p o r t e d in a s t u d y o f the traditional Zambian "Seven days" b e e r based on ma i ze and s o r g h u m (Love lace and N y a t h i , 1977) . Also, t h e S o u t h A f r i c a n t r a d i t i o n a l b e e r s w e r e f o u n d t o c o n t a i n s i g n i f i c a n t l y h igh levels o f f u s e l (high) a lcohols (O 'Donovan and Novel l ie , 1966) . The e f f e c t s o f f u s e l oils on human m e t a b o l i s m a r e d i f f i c u l t t o assess, b u t some a u t h o r i t i e s a t t r i b u t e c e r t a i n u n d e s i r a b l e e f f e c t s o f excess ive c o n s u m p t i o n o f a lcohol ic b e v e r a g e s t o t h e f u s e l oil c o n t e n t ( S t e v e n s , 1960) . The c o n s u m p t i o n o f l a rge a m o u n t s o f s o r g h u m b e e r s has b e e n a s s o c i a t e d w i t h h igh i r o n (Fe ) -

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v e r l o a d a m o n g 8lack p o p u l a t i o n o f S o u t h e r n A f r ica (Derman e t . a l . , 1980) . This o v e r l o a d seems t o be d u e t o t h e e n h a n c e d i r o n a b s o r p t i o n f r o m t h e b e e r ; t h e m inera l s o u r c e b e i n g t h e b r e w i n g m a t e r i a l s and t h e u tens i l s used .

I n a d d i t i o n t o s t a n d a r d i z i n g t h e p r o d u c t , u r g e n t s t u d i e s a r e r e q u i r e d t o i n v e s t i g a t e t h e s h e l f l i f e o f t h e p r o d u c t . The t r a d i t i o n a l b e e r s a r e c o n s u m e d s t r a i g h t a w a y , and a t m o s t w o u l d r e m a i n a c c e p t a b l e f o r a f e w days. A c r i d t a s t e d e v e l o p m e n t has b e e n r e p o r t e d by Van d e r W a l t d u e t o A c e t o b a c t e r a c t i v i t y in s t o r e d s o r g h u m b e e r s ( s t o r a g e t i m e , 2 t o 3 days) . This o f f - f l a v o u r d e v e l o p m e n t is p r e c e d e d by s e d i m e n t a t i o n o f t h e s u s p e n d e d sol ids. The k e e p i n g q u a l i t y m i g h t e v e n t u a l l y t u r n o u t t o b e t h e l im i t i ng f a c t o r f o r t h e scale o f i n d u s t r i a l o p e r a t i o n s o f a s c i e n t i f i c a l l y p r o c e s s e d a lcohol ic s o r g h u m b e v e r a g e .

4.4 Economic A s p e c t s

The b e n e f i t s o f t h i s n u t r i t i o n a l l y s i g n i f i c a n t (Aucamp e t . al. , 1961 ; Chevassus -Agnes e t . at., 1976 ; D e r m a n e t . al . , 1980) b u t t r a d i t i o n a l l y a c c e p t a b l e a lcohol ic s o r g h u m b e v e r a g e based on local raw m a t e r i a l s c o u l d be r e a p e d only i f i t is c o m m e r c i a l l y p r o d u c e d t o fa l l w i t h i n t h e means o f t h e peasants in t h e r u r a l a reas .

The e c o n o m i c a s p e c t s o f th i s v e n t u r e c o u l d n o t be d iscussed a t l e n g t h in t h i s in i t ia l s t a g e o f s c i e n t i f i c i n v e s t i g a t i o n ; only one s i g n i f i c a n t o b s e r v a t i o n c o u l d be made . E f f o r t m u s t be e x p e n d e d t o i d e n t i f y i nexpens ive a l t e r n a t i v e local m a t e r i a l s , w h e r e v e r poss ib le , t o s u b s t i t u t e f o r t h e p r o c e s s i n g a i d s / a d d i t i v e s , in t h e b r e w i n g p r o c e d u r e o f s o r g h u m b e v e r a g e s .

I n t h i s c o n t e x t , t h e use o f Magadi Soda f o r t h e d e t o x i f i c a t i o n o f t a n n i n s shou ld b e i n v e s t i g a t e d in p r e f e r e n c e t o t h e e x p e n s i v e f o r m a l d e h y d e and c o n v e n t i o n a l alkali m a t e r i a l s . Also, t h e poss ib i l i t y o f u t i l i z i n g cane molasses, an u n d e r u t i l i z e d b y - p r o d u c t f r o m t h e Tanzan ian Sugar i n d u s t r y , in p lace o f honey and r e f i n e d sugar , f o r

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enhanc ing t h e f e r m e n t a t i o n a c t i v i t y in t h e p r o d u c t i o n o f

I n t u r i l e shou ld b e e x p l o r e d .

5.0 CONCLUSION

In s p i t e o f t h e i r immense s o c i o - e c o n o m i c s i g n i f i c a n c e , t h e t r a d i t i o n a l a lcohol ic b e v e r a g e s o f Tanzania , wh ich d i f f e r in t r ins ica l l y f r o m t h e W e s t e r n b e e r s , have y e t t o b e d e v e l o p e d on sound t e c h n o l o g i c a l basis f o r c o m m e r c i a l e x p l o i t a t i o n . These a lcohol ic b e v e r a g e s a r e many and v a r i e d , near l y each d i s t r i c t o f t h e c o u n t r y having i ts own " b r a n d s " ; h o w e v e r , m o s t o f t h e m a r e based on ce rea ls , p a r t i c u l a r l y s o r g h u m .

The s c i e n t i f i c i n v e s t i g a t i o n o f Mtama b e e r , t h e m o s t p o p u l a r t r a d i t i o n a l s o r g h u m b e v e r a g e , seems t o b e a p r o m i s i n g ' s t a r t i n g p o i n t f o r he t e c h n o l o g i c a l d e v e l o p m e n t . An i n t e g r a t e d a p p r o a c h shou ld be p e r s u e d in th i s t e c h n o l o g i c a l a c t i v i t y t o e x p l o r e t h e f e a s i b i l i t y o f p r o d u c i n g an a lcohol ic s o r g h u m b e v e r a g e o f u n i f o r m q u a l i t y c h a r a c t e r i s t i c s on a m e d i u m scale in t h e Tanzan ian e n v i r o n m e n t .

I t remains a cha l lenge f o r t h e s c i e n t i f i c c o m m u n i t y o f Tanzania t o d e v e l o p t h e s e t r a d i t i o n a l a lcohol ic b e v e r a g e s i n t o s u c c e s f u l c o m m e r c i a l y v iab le v e n t u r e s .

ACKNOWLEDGEMENT

I am g r a t e f u l t o Mr. Paul V a r o d a y a n , my co l league a t t h e Un ive rs i t y D e p a r t m e n t o f Techno logy , C h e m i s t r y and -M ic rob io logy o f Foods , R U G - F a c u l t y o f A g r i c u l t u r a l Sc iences , G h e n t , Belg ium, f o r his c o n s t r u c t i v e ideas in p r e p a r i n g t h e m a n u s c r i p t , and t o t h e Se rv ice o f P r o f e s s o r Dr. I r . A. H u y g h e b a e r t f o r p r o v i d i n g f a c i l i t i e s f o r t h e l a b o r a t o r y w o r k . Some i l l u s t r a t i o n s w e r e s u p p l i e d by I r . P. Van Damme o f RUG-T r o p i s c h e P l a n t e n t e e l t en Economie ; he is h ighly a c k n o w l e d g e d . F o r t y p i n g , I t h a n k my w i f e Mrs. Jasmine Ti isekwa.

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BIBLIOGRAPHY

AUCAMP, M X . ; GRIEFF, J.T. ; NOVELLIE, L. ; PAPENDICK, B. ; SCHWARTZ, H.M. and STEER, A.G. (1961) : N u t r i t i v e Value o f Some K a f f i r c o r n P r o d u c t s , J. Sei. Food Agr ic . 1 2 : 4 4 9 - 4 5 6 .

CHEVASSUS-AGNES, S. ; FAVIER, J X . and ORSTOM, A.J. (1976) : T r a d i t i o n a l Techno logy and N u t r i t i v e Value o f S o r g h u m Beer in C a m e r o o n ; Cahiers d e N u t r i t i o n e t d e D i t t i q u e 1 1 : 8 9 - 1 0 4

DAIBER, K.H. (1975) : E n z y m e I n h i b i t i o n by Po lypheno ls o f S o r g h u m Grain and Mal t , J . Sei. F o o d A g r i c , 2 6 : 1 3 9 9 - 1 4 1 1 .

DERMAN.D.P. ; BOTHWELL, T.H. ; TORRACE, J.D. ; BEZWODA, W.R. ; MAcPHAIL, A.P. ; KEW, M X . ; SAYERS, M.H. ; DISLER, P.B. and CHARLTON, R.W. (1980) : I r o n A b s o r p t i o n f r o m Maize (Zea mays) and S o r g h u m ( S o r g h u m v u l g a r e ) Beer , B r i t . J. N u t r . 4 3 : 2 7 1 - 2 7 9 .

DIRAR, H.A. (1978) : A M i c r o b i o l o g i c a l S t u d y o f Sudanese Merissa b r e w i n g . J. F o o d Sei. 4 3 : 1 6 8 3 - 1 6 8 6 .

FAO, (1983) : FAO P r o d u c t i o n Year Book 1982.

FAO (1986) : FAO P r o d u c t i o n Year Book 1985 FAO S t a t i s t i c s

Ser ies No. 70.

HESSELTINE, C.W. (1979) : Some I m p o r t a n t F e r m e n t e d Foods in M id -As ia , The Midd le East and A f r i c a , J. Am. Oil Chem. S o c , 5 6 : 3 6 7 - 3 7 4 .

KAYUMBO, H. (1985) : "Sc ience and Techno logy in Deve lop ing

C o u n t r i e s " , P a p e r p r e s e n t e d a t t h e Sc ience Sympos ium,

U n i v e r s i t y o f Dar -es - -Salaarn , Tanzan ia , S e p t . 1985.

LOVELACE, C.E.A. and NYATHI, C.B. (197 7) : E s t i m a t i o n o f Fungal Toxins, Zearatenone and A f l a t o x i n C o n t a m i n a t i n g O p a -q u e Maize Beer in Zambia , J . Sei . F o o d Agr ic . , 2 8 : 2 8 8 - 2 9 2 .

- 3 2 1 -

LUKOO, H.M. ; RWEHUMBIZA, A.K. and MOADILA, P. (1981) : P o t e n t i a l f o r S o r g h u m U t i l i z a t i o n in Tanzan ia , P a p e r p r e s e n t e d a t t h e Regional W o r k s h o p on C o m p o s i t e F lou rs , K h a r t o u m , S u n d a n , Dec. 1 9 8 1 .

MIROCHA.C.J., CHRISTENSEN, C M . and NELSON, G.H. (1971) . F~Z (Zeara lenone) e s t r o g e n i c m y c o t o n i x , Vol. 7 (S.Kadis, A. C iegler , and S.J. A j l , eds . ) , Academic Press , N.Y., p p . 1 0 7 -138.

MOSHA, A.C. ; KEPAKEPA, V.M.K, and MLINGI.B. (1977) : "Zao la M t a m a / U w e l e kama Chakula Bora cha B inadamu, LISHE, Tan z a m a F o o d and N u t r i t i o n J o u r n a l , No. 2.3., 1977. (in Swahili}

MOSHA, A.C. and LRRI, W . S . M . (1978) : An O v e r - v i e w o f t h e F o o d I n d u s t r y in Tanzan ia , In The F o o d P rocess ing I n d u s t r y in Tanzania , Food M a n u f a c t u r e r s W o r k s h o p in Tanzania , P r o c e e d i n g s - T F N C , e d . F. Gogomoka , 1978,

MUINDI, P.J. ; THOMKE, S. and EKMAN, R. ( 1 9 8 1 ) : E f f e c t o f Magadi Soda T r e a t m e n t , on t h e Tannin C o n t e n t and i,n-V i t r o N u t r i t i v e Value o f Grain S o r g h u m s , J. Sei . Food Agric... 3 2 : 2 5 - 3 4 .

NOVELLIE, L. (1962a) : E f f e c t o f Ma l t ing C o n d i t i o n s on t h e D ias ta t ic Power o f K a f f i r c o r n Mal t , J . Sei . F o o d A g r i c , 1 3 : 1 1 5 - 1 2 0 .

NOVELLIE, L. ( 1962b ) : V a r i a t i o n o f D ias ta t ic P o w e r w i t h V a r i e t y , Season, M a t u r i t y and Age o f Grain , J. Sei . F o o d A g r i c , 1 3 : 1 2 4 - 1 2 6 .

NOVELLIE, L. (1976) : Beverages f r o m S o r g h u m and Mi l lets , p r o c e e d i n g s o f a Sympos ium on S o r g h u m and Mil lets f o r Human F o o d , Pg. 7 3 - 7 7 . DAV Dend , e d . T rop ica l P r o d u c t s I n s t . , L o n d o n .

NOVELLIE, L. (1982) : F e r m e n t e d Beverages , I n P r o c e e d i n g s o f t h e I n t e r n a t i o n a l Sympos ium on S o r g h u m Grain Qua l i ty , Pg. 1 1 3 - 1 2 0 ; P a n t a c h e r u , ICRISAT, A.P., I nd ia .

- 322 -

NTIRUBAHAMWE, P. (1985) : Persona l C o m m u n i c a t i o n on B r e w i n g e x p e r i e n c e s , P.O. Nyakahura , B iharamulo , Tanzania .

0'DONOVAN, M.B. and NOVELLIE, L. (1966) : The f u s e l Oils o f K a f f i r Beer , 3. Sei. F o o d A g r i c , 1 7 : 3 6 2 - 3 6 5 .

PEARSON, 0.(19 70) : The Chemical Analysis o f Foods . S i x t h e d i t i o n , J . and A, Church i l l , L o n d o n .

SHERWOOD, R.F. and PEBERDY, J.F, (1974) : P r o d u c t i o n o f M y c o t o x i n , Z e a r a l e n o n e by Fusar ium G r a m i n e a r u m Growing on S t o r e d Grain I. Grain S t o r a g e a t R e d u c e d T e m p e r a t u r e s . 3. Sei. F o o d Agr ic . 2 5 : 1 0 8 1 - 1 0 8 7 .

STEVENS, R. (1960) : Beer F lavour . I. Vo la t i le P r o d u c t s o f F e r m e n t a t i o n : A rev iew. 3. I n s t . Brew. Vol .66, p p . 4 5 3 - 4 7 0 .

VAN DER W A L T , J.P. (1956) : S t u d i e s on t h e M ic rob io logy o f

K a f f i r Beer , 3. Sei . F o o d A g r i c , 7 : 1 0 5 - 1 1 3 .

WERNER, D. (1985) : A Vil lage Care Handbook : W h e r e t h e r e is no D o c t o r . Macmil lan Pub l ishers .

Beer p r o c e s s i n g in Unyamwezi (Tanzania) c i r c a 1 8 5 0 . Engraving from : Capitaine SPEKE. Les sources du Nil. Journal d'un voyage de dcouvertes. In : Le Tour du Monde. Nouveau journal des voyages. 1864, premier semestre. P a n s , Hachette, 1864.