After the fermentation process was completed, all the apparatus needed for boiling were prepared as shown in the diagram below. The fermented mixture was then boiled in the clay pot. As it boiled, then the distillate which is an alcohol called Ombike in Oshiwambo was collected at the end of the metal tube into the collecting container.
75 Figure 4.5.1: Ombike traditional distillation equipment
Question 1- What do you think is the function of the metal tube used in this activity? G1: To be an entry for the evaporating steam inside the boiler
G2: Is where Ombike moves from the clay pot to the collecting bottle
G3: To transport the gas that is converted to liquid to the receiver. It is also where condensation takes place.
Question 2:- Explain what would happen if the boiling pot is not sealed properly. G1: Ombike will pass out in the form of water vapour and could not reach the receiver. G2: The traditional alcohol will be less because some water vapour will pass out through those cracks into the atmosphere.
G3: Ombike will evaporate through those openings and could not be collected through the condenser.
Question 3:- The cold water is always put in the trough over the metal tube in the trough. Once the water becomes hot, it is quickly removed and replaced with cold water again.
a) What is the reason of putting cold water over the metal tube in the trough? G1: So that the vapour will change into water droplets which will turn to Ombike.
G2: To cool down the metal tube so that Ombike will condense and come out in the form of liquid.
G3: To cool down the vapour that pass through the tube and then for that vapour to condense. b) Explain how and why does this water get hot?
G1: the water will get hot because the gas which is coming out from the pot is hot causing the metal tube to be hot too because metals are good conductors of heat.
76 G2: Because of the heat in the vapour from the boiler, as it touches the tube, the tube becomes hot and then passes on the heat to the water.
c) Explain what could happen if no cold water was placed in the trough.
G1: No condensation process will take place. Ombike will evaporate in the form of gas to the atmosphere. So no liquid comes out, only a smoke you can see.
G2: Most of Ombike would escape in a gas state.
Question 4: Give the scientific explanations or reasons for the following statements;
Crushing the fruits into very small pieces:
G1: So that the water will mix nicely and at the end the Ombike produced will taste stronger. G2: Fermentation starts at this stage, thus it will make it easier when mixing them with water so that there will be a taste.
G3: In order for fermentation to take place faster by increasing the surface area.
Covering the mixture in a plastic bucket for about four days:
G1: For oxygen not to enter into the mixture, because once it enters water will be the product instead of ethanol.
G2: For the carbon dioxide produced not to escape because it will be needed in dissolving the taste of the mixture into acidic taste since it is an acidic gas.
G3: To prevent the entrance of oxygen and also to make the temperature range constant.
The last distillate of Ombike is found to be weak and tasteless compared with the first distillate:
G1: The first distillate is pure Ombike and as the alcohol get finished then it becomes weaker because now it is now moves toward water.
77 G2: The first is pure Ombike and the last one is omatshatsha which contains little alcohol and more water.
Based on the questions and responses above, I realised that many learners were able to fully make use of and incorporate the knowledge that they had gained from the previous session. The sessions that most contributed to these responses were the brainstorming, discussion with the expert, and the session about the introduction of the concepts under study. Learners were thus able to use the needed scientific understanding in answering the posed questions.
Responses given for not frequently opening the container were more scientifically appropriate to the level of these learners (grade 9). Learners had to translate the responses given by the expert when the same question was posed to her. Although the expert explained concepts such as ‘air will spoil the mixture’, scientific concepts such as; oxygen, oxidises, water and carbon dioxide were evident in their explanations.
Although most literatures recommend the use of IK in the science classrooms, it is important to note that not all community knowledge is relevant. It is therefore a good idea to create a platform to correct any misconceptions that might exist in the community. I am relating this to some of the responses given by learners which could be beliefs they had heard from their community. For example, when asked to explain why the addition of sugar to the fermenting fruits was not recommended, learners in group three (G3), replied that ‘it causes TB’. This might be confusing and as it requires more clarification on how sugar causes TB.
I also realised that teachers need to emphasise to the learners the importance of integrating topics in science. I found from learners’ responses that they were able to use knowledge from other topics to explain certain concepts. For example, in the responses given, I could see the use of other topics used in this context of making Ombike such as; matter (states, condensation, vapour...), conduction (heat, metals...), chemical reactions (equation), health (effects of adding sugar).
4.6 Concluding remarks
This chapter presented and analysed the findings from the brainstorming, discussions, practical demonstration and lesson observations. It is clear from the presentations that the
78 elicitation of learners’ prior knowledge is something of crucial importance. It formed a strong foundation which could give a clear direction to the teacher to know the kind of learners he/she is working with.
The data revealed that the use of community knowledge and experiences could be a remedy in schools where teaching and learning materials are not available. The explanations from the expert showed that, despite their low academic background, the knowledge of the community and their cultural practices might well be usable; hence studies like thses are needed.
79 CHAPTER FIVE
DATA PRESENTATION AND ANALYSIS: PHASE TWO 5.1 Introduction
In this chapter, I present and analyse the data from the observation of the lessons on practical activities as well as the worksheets. As a continuation to the previous chapter, I thus present the data from the two remaining stages of the research process, namely:
Stage 5: data from practical activities; and
Stage 6: data from the interviews on the participants’ evaluations and recommendations.
I now discuss each of these below.