r 9871 OJOMO:PALM SAPAND

Principes,3l(4),1987, pp. 169 171

Componentsof Fermenting Palm and Bottled

EnweRoE. Orouo Nigerian Institute.fbr OiI Palm Research (NIFOR) , P.M.B. 103O, Benin City, Nigeria

ABSTRACT enous flora of the palm trees and from equipment used in collecting the sap (Oka- associated The length of preservation and bacteria for 1975, Ojomo et al. l9B4). with the variation in the components of palm sap Nigerian Institute for Oil Palm during fermentation were investigated at room tem- The perature. The fermenting palm sap at room temper- Research (NIFOR) has successfully ature deteriorated after two days of storage; while its desiened and made its own Ceneral Pur- counterpart treated at 75" C for 30 minutes stored pore Watetbath for bottling palm wine' at room temperature for 12 months. There was well The need has arisen to investigate the effi- a sequence in the bacteria genera (Micrococcus, Streptoc.occus, Leuconostoc, Lactobacillus and Ace- ciency of the waterbath to ensure that the tobacter) isolated during the palm sap f'ermentation. bottled palm wine can be preserved for up The activities of these microorganisms result to changes to twelve months without appreciable dete- of in the composition of the chemical constituents rioration of quality. I report here the palm sap and palm wine. Whereas, NIFOR fabricated composition and the general purpose waterbath at 75'C for 30 minutes changes in bacteria inhibired the prolileration of bacteria. major chemical constituents of fresh and bottled palm wine due to the activities of microorganisms. The incorporation of bottled palm wine (fermented palm sap) into the local bev- erage market is currently gaining wide acceptability in Nigeria. Palm wine is a Materialsand Methods popular traditional African beverage which is obtained by tapping Raphia palrn Aliquotsof 630 mL of freshlycollected (Raphia hookeri G. Mann and H. A. Raphia palm wine were crowncorked and Wendl.) and oil palm (Elaeis gulneensis then pasteurized by treating in NIFOR Jacq.) trees. Palm sap ferments easily, and waterbath at 75" C for 30 minutes and becomes sour within a few hours of col- stored for periods ranging 2-12 months lection. When fresh it is sweet, refreshing, ar 28o C. The unbottled palm sap was nourishing and a nutritious drink contain- allowed to ferment in the air at room tem- ing sugar, vitamins and minerals. Raphia perature for 5 days. During the fermen- palm wine has a sugar content of about tation and at 3 months interval (bottled 6-8%, an acidity (calculated as acetic acid) palm wine), I mL samples were used for of about O.47o and protein (% w/v) of chemical analyses; pH was determined about 0.05% (Eapen 1982, Okiy and using pH meter; alcohol was determined Ojomo 1985). Within 24 hours of fer- by gas liquid chromatography according mentation, sugar content reduces to 0.5 to the procedure of Sharma et al. (1984); I7o while acidity increases to 0.5 0.6% the total sugar content was determined by (Eapen 1982). Present in the wine are the anthrone method of Yemm and Willis various microorganisms (mainly bacteria (1954) and the acidity by titration against and ) which originate from the indig- 0.1 N sodium hydroxide. Media and meth- PRINCIPES [Vor.31

Table l. Bacterial uariability durirug fresh palm sap fermentation.

Bacterial Genera

Day I Micrococcus, Streptococcus, Leuconostoc. 2 Micrococcus, Streptococcus, Leuconostoc, Lactobacillus. 3 Micrococcus, Streptococcus, Lactobacillus, Acetobacter. 4 Micrococcus, Streptococcus, Laetobacillus, Acetobacter. 5 Micrococcus, Streptococcus, Acetobacter.

Table 2. Bacteria associated uith bot- Resultsand Discussion tled palm wine. Due to microbial variability changes in

Bacterial Genera the components of fresh palm sap during fermentation were observed. At atmo- Months I 3 spheric temperature, the sugar concentra- 6 Lactobacillus tion of the palm sap started to {all after a 9 Lactobacillus few hours and fermentation was completed I2 Lactobacillus within four days. As from the second day (Table 3), sugar decreased in concentra- tion; the concentration fell from 7.57o to Table 3. Chemical conl.ponentsof fresh 5.27o on the first day, and less than half palm sap during fermentation. of the first day value after a period of three days. This fall was accompanied by a pro- Alcohol Acidity gressive increase in acidity and a sharp pH Sugar (%) (%) (%) rise in the level of alcohol concentration. Duy At this stage, the palm wine contained l- (fresh) 1 3.83 7.s 2.0 .35 27o alcohol after 24 hours fermentation 2 3.64 5.2 3.8 and its value never rose beyond 4.57o a{ter 3 3.53 2.4 4.5 72 hours. A fresh sap contains no alcohol, 4 J.J 2.2 3.6 .5 5 t.2 3.2 but after a few hours the production of alcohol usually begins, with rapid evolution of CO, (Faparusi and Bassir, 1972). Table 4. Chemical componentsof bot- At pH 3.5 to 4.0, the palm wine is tled palm nine. considered suitable for drinkine. Within 24 hours of tapping, the pH of the fermenting Sugar Alcohol Acidity sap fell rapidly from 7.0 to 3.83. At this pH (%) (%) (%) stage of the palm sap fermentation, the Months I 3.83 7.5 2.O .35 degree of infection is high. The lowering 3 3.85 7.3 2.05 .36 pH and rising alcohol content are both 6 3.9 7.28 2.1 .36 factors resulting from the metabolic activ- 9 3.9s 7.27 2.r5 .37 ities of the bacteria which get into the sap 12 3.85 7.2 2.t .375 as it drips out of the tree (Table I). Bac- teria which are always present in the palm wing during the five days' analyses are ods for bacteria isolation procedure were Micrococcus and.Streptococcus. The lac- of Ojomo et al. (1984). Bacteria identifi- tic acid bacteria isolated include certain cation was in accordance with the method species in the genera Streptococcus, Leu- described by Buchanan et al. (1975). conostoc and Lactobaclllzs. Fermentation r 9B7l OJOMO:PALM SAPAND WINE was started by the bacterial genera Strep- Acknowledgments tococcus and,Leuconosroc (Tables I and The author is grateful to the Director, 3). The sugar was converted to lactic acid, NIFOR and membersof the Plant Pathol- alcohol, acetic acid and other products. As ogy Division. the acids accumulate, Leuconostoc was inhibited after day 2, but the fermentation continues with Lactobacillus. A slight fall LrreRetunn CIrso of alcohol level after the third day is due Bergey'smanualofdeter- to oxidation of alcohol by a newly invading BucHANANETAL.I975. minative bacteriology,8th ed. Williams and Wil- Its appearance species oI Acetobacter. kins Company,Baltimore, MD, U.S.A.,p. 1268' decreased the alcohol percentage from EAPEN,P. I. 1982. Some studieson the preser- 4.57o to 3.6uo and there was an increase vation and bottling of Palm Wine. J. Nig. Inst. in acidity. Okiy and Ojomo (1985) reported for Oil Palm Res. 6: 2I7 221. FApARUSI.S. I. errro BASSIR,O. 1972. Factors that a good quality fresh or bottled palm affecting the quality of palm wine 2. Period of wine should possessthe following charac- Storage.West Afric. Jour. Biol.and App[.Chem. teristics: Sugar level not less than 67o, I5:24 28. alcohol concentration of about 27o and Olono, E. E., ADERUNGBoYT,F.O. lNn Nwosu, S. on the microbiologyof NIFOR acidity level not more ihan 0.57o. Using O. 1984. Studies Raphia and Oil Palm Wine. Canadian Institute the fermenting palm the ahove criteria, of Food Scienceand TechnologyJournal 17: sap at room temperature deteriorated after 172-174. two days of storage. W'hereas, the major OKAFoR,N. 1975. Microbiologyof NigerianPalm chemical constituents of the bottled palm Wine with particular reference to bacteria. Jour- nal of Appiied Bacteriology38: BI 88. wine remained normal after 12 months of Oxrv, D. A. anl OJouo, E. E. 1985. A sampling storage at room temperature. The activi- of the quality of some brands of Palm Wine ties of the microorganisms using NIFOR bottled in Nigeria. J. Nig. Inst. for Oil Palm All Purpose Waterbath at 75" C for 30 Res. 7. Maximisation of fuel minutes were inhibited. So far, attempts SnaRrr,reET AL. 1984. 'NIFOR from Pawpawfermentation- Energy 9: 15 20. wine by use of to preserve palm YEMM.E. W. nNl WILLIS,A. J. 1954. The esti- waterbath have produced acceptable mation carbohydrates in plant extracts by results. anthrone.Biochem. J. 57: 508.

THE 1988 BIENNIALMEETING

The next Biennial Meeting of The International Palm Society will be held in Queensland, Australiain the latter part of September1988, with two tentative Post Biennialoptional tours, (l) Australia or (2) New Guinea. Details concerningitineraries, accommodations, and costs will be included in a forthcoming issue of Principes. Meanwhile save your penniesand join fellow membersin 1988 down under. ElweRn M. McGoHBe,President The International Palm Society