LUI A.J. BELL, POSA SKELTON and TAVITA SASI
- This study examined the acceptability of the Nile tilapia as a food fish in Samoa, particularly with reference to the nearshore reef fish species. Two traditional methods of cooking fish were used, cooked (boiled) in coconut cream and cooked in a Samoan “umu” with fish wrapped in breadfruit leaves.
Only Nile tilapia were cooked in coconut cream but taster were asked to compare its taste to that of reef fish. The results showed that of the 43 people that participated in this particular survey, 21 (48.8%) rated Nile tilapia as tasting the same as reef fish, 20 (46.5%) rated Nile tilapia as tasting better than reef fish, while only 2 (4.7%) rated Nile tilapia as tasting worse than reef fish.
Nile tilapia and various species of reef fish were cooked in the Samoan “umu” and tasters had the chance to evaluate both “on-the-spot”. The overall results showed that of the 72 people that participated in this particular survey, 9 (12.5%) rated both Nile tilapia and reef fish as having the same taste. Thirty people (41.7%) rated Nile tilapia as tasting better than reef fish while 33 (45.8%) rated reef fish as tasting better than Nile tilapia.
The results clearly show that creating alternative fish production for consumption and as a source of income, using Nile tilapia, is a very viable venture. This in turn will divert pressure from the over-exploited nearshore fishery resources.
Discussion on specific aspects and other details of the survey are included.
In 1995, Fisheries Division, Ministry of Agriculture, Forests, Fisheries and Meteorology, Samoa, conducted a comparative taste study using Nile tilapia, bottomfish and skipjack tuna during the Fisheries Division Open Day. Fresh (chilled) Nile tilapia was imported from Fiji with the financial assistance of the South Pacific Aquaculture Development Project (SPADP II).
Due to the very encouraging results from the first taste study and the fact that inshore reef and lagoon fish are much more widely consumed in Samoa at all levels, it was decided to repeat the study but comparing Nile tilapia and nearshore reef fish species. Taste testing was conducted during the Fisheries Division Open Day on 8 November, 1996. Nile tilapia for this study was again imported from Fiji.
These studies form part of the Fisheries Division's effort to create alternative sources of fish in order to reduce pressure on the fishery resources in the nearshore reefs and lagoons. It has been established that the nearshore fishery resources have been over-exploited. Inland fish farming as well as stocking inland natural and man-made bodies of water offer potential in increasing fish production thus diverting effort from utilising the over-exploited nearshore resources.
With the assistance of the SPADP (II) approximately 100 kg of Nile tilapia (chilled on ice), with an average weight of 300g each, were imported from Fiji three days before the Fisheries Open Day. These were all kept on ice until cooking on the Open Day, 8 November 1996. Five strings of reef fish, consisting of various species, were bought from the Apia Fish Market the day before the Open Day and were kept in the Division's freezer and cooked the following morning.
Fish cooked (boiled) in coconut cream is one of the most common and preferred traditional way of cooking fish in Samoa. For this study, tilapia specimens were washed with fresh water before boiling them in coconut cream. Salt and onion were added.
Cooked tilapia was placed on a tray and people tasted them from there. Tasters were aware or informed that the fish being tested was Nile tilapia. For this survey, there were no reef fish cooked in coconut cream for comparative tasting but tasters were asked to compare the taste of tilapia to that of reef fish. The questionnaire used is appended as Appendix 1.
Fish wrapped in breadfruit leaves and baked in an “umu” is another common and preferred traditional method of cooking fish in Samoa. For this study, Nile tilapia was salted on the outside and two to three specimens were wrapped in a large breadfruit leaf. Reef fish used for the study was treated the same way. The wrapped fish was placed on hot stones with other hot stones placed on the top and then covered with leaves. The fish was baked for about one hour.
After cooking, the breadfruit wrappings were removed and the fish placed on a tray. Reef fish and Nile tilapia were placed side-by-side on the same tray. Since most people had known Nile tilapia from the 1995 taste study, people were aware or told that the fish being tested were reef fish and tilapia. All information was recorded on a questionnaire form appended as Appendix 2.
The reef fish used in this study are as follows:
| Common name | Local name |
|---|---|
| Lined surgeonfish | Alogo |
| Bristle-tooth surgeonfish | Pone |
| Parrotfish | Fuga/Ulapo |
| Trevally | Lupo |
| Goatfish | Taulaia/Vete |
| Emperorfish | Mataeleele |
| Squirrelfish/Soldierfish | Malau |
While people were tasting Nile tilapia cooked in coconut cream, several questions were posed to them and answers recorded on a questionnaire. As mentioned above, there were no reef fish cooked in coconut cream but tasters were asked to compare the taste of tilapia to that of reef fish.
The results for the taste survey on Nile tilapia cooked in coconut cream are presented in Table 1. A total of forty-three (43) people were involved. Of this total, 21 (48.8%) rated Nile tilapia and reef fish as tasting the same. 20 (46.5%) rated Nile tilapia as tasting better than reef fish, while only 2 (4.7%) respondents rated Nile tilapia as tasting worse than reef fish.
Table 1. Results of comparative taste survey on Nile tilapia cooked in coconut cream with salt and onions, compared to reef fish.
| Tasters | Preference (tilapia vs. reef fish) | Total | ||
|---|---|---|---|---|
| Same | Better | Worse | ||
| Number | 21 | 20 | 2 | 43 |
| (Percentage) | (48.8) | (46.5) | (4.7) | (100) |
In terms of responses to the question, Any difference in taste between this fish and other reef fish?, 18 (83.8%) responded that there was a difference in taste between Nile tilapia and reef fish while 4 (18.2%) rated both Nile tilapia and reef fish as having no difference in taste. The difference in taste as indicated by participants between Nile tilapia and reef fish are presented in the following Table 2.
Table 2. Taste differences between Nile tilapia and reef fish as noted by tasters
| Tilapia Ranking | Taste differences noted by tasters | Total | ||||
|---|---|---|---|---|---|---|
| Soft | Tasty | Fatty | Too soft | No. | % | |
| Tasted like reef fish because | 2 | 2 | 4 | 18.2 | ||
| Tasted better than reef fish because | 6 | 6 | 5 | 17 | 79.3 | |
| Tasted worse than reef fish because | 1 | 1 | 4.5 | |||
| Total | 8 | 8 | 5 | 1 | 22 | 100 |
3.1.1 By gender
The results of the survey, sorted by sex, are presented in Table 2. Thirteen of the total number of tasters were females and thirty were males. Of the females, 8 (61.55%) rated Nile tilapia and reef fish as tasting the same while 4 (30.8%) rated Nile tilapia as tasting better than reef fish and 1 (7.7%) rated Nile tilapia as tasting worse than reef fish. For the thirty males, 13 (43.3%) rated Nile tilapia as having the same taste as reef fish, 16 (53.3%) rated Nile tilapia as tasting better and 1 (3.3%) rated Nile tilapia as tasting worse than reef fish.
3.1.2 By age groups
Age groups were sorted out as was done in the previous study comparing Nile tilapia, bottomfish and skipjack. Results are presented in Table 3. In this study, only 2 tasters were within the 6–15 year old group and all of them rated Nile tilapia as better tasting than reef fish.
A total of 10 tasters were in the 16–25 year old age group and 5 (50.0%) rated Nile tilapia and reef fish as tasting the same and the other 5 (50.0%) rated Nile tilapia as tasting better. None rated Nile tilapia to be tasting worse than reef fish.
The majority (22) of tasters were in the 26–35 year old group. Of the total 22 tasters in this group, 12 (54.5%) rated both Nile tilapia and reef fish to have the same taste. 8 (36.4%) rated Nile tilapia as tasting better than reef fish while only 2 (9.1%) rated tilapia as tasting worse than reef fish.
Nine of the total tasters were in the 36+ year old group, and 4 (44.4%) rated both Nile tilapia and reef fish as tasting the same while 5 (55.6%) rated Nile tilapia as having a better taste. None of the respondents rated tilapia as having a worse taste.
Table 3. Results of comparative taste survey sorted by gender on Nile tilapia and reef fish cooked in coconut cream
| Gender | Preference | Total | ||
| Same | Better | Worse | ||
| Male | 13 | 16 | 1 | 30 |
| (%) | (43.3) | (53.3) | (3.4) | (100) |
| Female | 8 | 4 | 1 | 13 |
| (%) | (61.5) | (30.8) | (7.7) | (100) |
Table 4. Results of comparative taste survey sorted by age group on Nile tilapia and reef fish cooked in coconut cream
| Age Group | Number of tasters | Preference (tilapia vs. reef fish) | ||
|---|---|---|---|---|
| Better | Same | Worse | ||
| 6–15 (%) | 2 | 2 (100) | 0 (0) | 0 (0) |
| 16–25 (%) | 10 | 5 (50) | 5 (50) | 0 (0) |
| 26–35 (%) | 22 | 8 (36.4) | 12 (54.5) | 2 (9.1) |
| 36+ (%) | 9 | 5 (55.6) | 4 (44.4) | 0 (0) |
| Total | 43 | 20 | 21 | 2 |
As was the case for the survey of fish cooked in coconut cream, people were asked several questions concerning the taste of both Nile tilapia and reef fish while they were tasting the two different fishes.
A total of 72 people participated in the survey comparing taste of Nile tilapia and reef fish cooked in a Samoan “umu”. The results are presented in Table 5. Of the 72 respondents, 9 (12.5%) rated Nile tilapia and the reef fish as tasting the same. However, 30 (41.7%) rated Nile tilapia as tasting better while 33 (45.8 per cent) rated reef fish as tasting better.
Table 5. Results of comparative taste survey on Nile tilapia and reef fish wrapped in breadfruit leaves and cooked in a Samoan “umu”.
| Tasters | Preference (tilapia vs. Reef fish) | Total | ||
|---|---|---|---|---|
| Same | Better | Worse | ||
| Number | 9 | 30 | 33 | 72 |
| (Percentage) | (12.5) | (41.7) | (45.8) | (100) |
Table 6 presents the differences in taste as indicated by participants who recognised a difference in taste between Nile tilapia and reef fish tasted.
Table 6. Differences in taste between Nile tilapia and reef fish as noted by tasters
| Taste Difference | Ranked both Fish the Same | Ranked Nile Tilapia Better | Ranked Reef Fish Better | Total | |
|---|---|---|---|---|---|
| Numbers | % | ||||
| Tilapia soft | 4 | 9 | 9 | 22 | 32.7 |
| Tilapia salty | 1 | 2 | 3 | 4.5 | |
| Tilapia fleshy | 3 | 1 | 4 | 6.0 | |
| Tilapia fatty | 7 | 1 | 8 | 11.9 | |
| Tilapia smells good | 1 | 1 | 2 | 3.0 | |
| Reef fish softer | 1 | 1 | 1.5 | ||
| Reef fish tasty | 4 | 4 | 6.0 | ||
| Reef fish firm | 2 | 5 | 7 | 10.4 | |
| Reef fish fresh | 3 | 3 | 4.5 | ||
| Reef fish salty | 3 | 10 | 13 | 19.5 | |
| Total | 5 | 27 | 35 | 67 | 100.0 |
3.2.1 By gender
Results, sorted by sex, are presented in Table 6. 21 (29%) of the total number of tasters were females and 51 (71%) were males. Of the female respondents, 2 (9.5%) classified Nile tilapia as having the same taste as reef fish, 8 (38.1%) rated Nile tilapia as tasting better, while 11 (52.4%) rated reef fish as tasting better.
For the male respondents, 8 (13.7%) rated Nile and reef fish as tasting the same and the number of respondents preferring Nile tilapia were the same as those preferring reef fish, i.e. 22 (43.1%) each.
3.2.2 By age groups
Table 7 presents results sorted by age groups. Two of the respondents did not specify their ages and were excluded for this portion.
As recorded in the other study, the lowest number of participants was in the 6–15 year old group. This group was represented by only 5 participants in this part of the survey and 3 (60%) rated Nile tilapia as tasting better while the other 2 (40%) rated reef fish as having a better taste. The 16–25 year old group was represented by 13 people of whom 2 (15.4%) rated both Nile tilapia and reef fish as tasting the same while 6 (46.2%) preferred the taste of tilapia and 5 (38.5%) preferred reef fish. The third age group, 26–35 year of age, had a total of 23 respondents. 4 (17.4%) rated Nile tilapia as tasting the same as reef fish, 11 (47.8%) rated Nile tilapia a as tasting better while 8 (34.8%) rated reef fish as tasting better. There were 29 respondents in the 36+ year old group. Of this total, only 2 (6.9%) rated Nile tilapia and reef fish as tasting the same, 9 (31.0%) preferred Nile tilapia over reef fish while 18 (62.1%) rated reef fish as tasting better than Nile tilapia.
Table 7. Results of comparative taste survey sorted by gender on Nile tilapia and reef fish cooked in a Samoan “umu”
| Gender | Preference | Total | ||
| Same | Better | Worse | ||
| Male | 22 | 7 | 22 | 51 |
| (%) | (43.1) | (13.8) | (43.1) | (100) |
| Female | 8 | 2 | 11 | 21 |
| (%) | (38.1) | (9.5) | (52.4) | (100) |
Table 8. Results of the taste survey sorted by age on Nile tilapia and reef fish cooked in a Samoan “umu”
| Age Group | Number of Individuals | Preference (tilapia vs. reef fish) | ||
|---|---|---|---|---|
| Better | Same | Worse | ||
| 6–15 (%) | 5 | 3 (100) | 0 (0) | 2 (40.0) |
| 16–25 (%) | 13 | 6 (46.2) | 2 (15.4) | 5 (38.5) |
| 26–35 (%) | 23 | 11 (47.8) | 4 (17.4) | 8 (34.8) |
| 36+ (%) | 29 | 9 (31.0) | 2 (6.9) | 18 (62.1) |
| Total | 70 | 29 | 8 | 33 |
3.2.4 Reef fish species
In order to see whether specific reef fish species have any effect on the responses, the data was sorted according to the reef fish species used for comparing taste with Nile tilapia. The results are presented in Table 9 on the following page.
Alogo (lined surgeonfish): Twelve people had a chance to taste “alogo” against Nile tilapia. Eight (66.7%) rated “alogo” as tasting better than Nile tilapia while 4 (33.3%) rated Nile tilapia as better.
Pone (bristle tooth surgeonfish): A total of fourteen people tasted “pone” against Nile tilapia. Seven (50.0%) ranked “pone” as a better tasting fish than Nile tilapia, 6 (42.9%) ranked Nile tilapia as better tasting while 1 (7.1%) ranked them the same.
Table 9. Results of the taste survey sorted by reef fish species tasted on Nile tilapia and reef fish species cooked in a Samoan “umu”
| Reef fish species used | Preference | Total | |||
|---|---|---|---|---|---|
| Tilapia better | Same | Reef fish better | No. | % | |
| Alogo (%) | 4 (33.3) | 0 (0) | 8 (66.7) | 12 | 100 |
| Fuga/Ulapo (%) | 16 (50.0) | 5 (15.6) | 11 (34.4) | 32 | 100 |
| Lupo (%) | 2 (50.0) | 0 (0) | 2 (50.0) | 4 | 100 |
| Malau (%) | 0 (0) | 0 (0) | 1 (100.0) | 1 | 100 |
| Mataeleele (%) | 0 (0) | 2 (50.0) | 2 (50.0) | 4 | 100 |
| Pone (%) | 6 (42.9) | 1 (7.1) | 7 (50.0) | 14 | 100 |
| Taulaia/Vete (%) | 2 (40.0) | 1 (20.0) | 2 (40.0) | 5 | 100 |
Fuga/ulapo (parrotfish): Thirty-two tasters had parrotfish tasted against Nile tilapia. Sixteen (50.0%) rated Nile tilapia as better tasting than parrotfish, 11 (34.4%) rated parrotfish as tasting better while 5 (15.6%) rated Nile tilapia and parrotfish the same.
Lupo (trevally): Only four people tasted “lupo” against Nile tilapia of whom half preferred tilapia and the other half preferred “lupo”.
Taulaia/vete (goatfish): Only five people tasted goatfish against Nile tilapia. Two (40.0%) preferred tilapia. Two (40.0%) preferred goatfish and one (20.0%) ranked both the same.
Mataeleele (emperor fishes): Only four people tasted emperorfish against Nile tilapia. Two (50.0%) ranked emperorfish as better than tilapia while the other two (50.0%) ranked Nile tilapia as the same as emperorfish.
Malau (squirrelfish/soldierfish): Only one person tasted “malau” against Nile tilapia, and he ranked the “malau” as better tasting than tilapia.
The two major differences between this study and that done previously are as follows:
This study used inshore reef fish which is more popular and commonly consumed The previous study used Bottomfish and Skipjack.
During this study, tasters knew or were informed before or while tasting that the fish being tested was Nile tilapia and reef fish. In the previous study, tasters were not informed of the fish being tested.
4.1 Nile Tilapia Cooked in Coconut Cream
The overall results of the study involving Nile tilapia cooked in coconut cream clearly indicate the acceptability of Nile tilapia as a food fish by Samoan people, even though the tasters knew that Nile tilapia is a fresh-water fish. The highest percentage of those who participated (48.8%) rated Nile tilapia as having the same taste as reef fish. A slightly lower portion of the total number of tasters (46.5%) rated Nile tilapia as tasting better than reef fish. A very minor portion (4.7%) rated Nile tilapia as tasting worse than reef fish.
When the results were separated according to sex, a much higher portion of the females rated Nile tilapia and reef fish as having the same taste, whereas males had a higher proportion rating Nile tilapia as a better tasting fish. This could be an indication of the difference in sharpness in taste ability by the different sex groups. Additionally, females could be more sensitive and less “adventurous” taking any risks in terms of food.
The youngest age group, 6–15 years old, was represented by only two. Both rated Nile tilapia as tasting better than reef fish. Their answers are probably reflective of the stage of development of their taste for fish. Interestingly, the oldest age group, 36+ years old and represented by 9 individuals, had a higher percentage rating Nile tilapia as better than reef fish. None of this age group rated Nile tilapia as tasting worse than reef fish. For the 16–25 years old group, half rated both Nile tilapia and reef fish as tasting the same while the other half rated Nile tilapia as tasting better. This age group probably represents those who are open for new “tastes” and have not yet become traditionalised in terms of tasting fish. In the 26–35 years old group, about 55% rated Nile tilapia and reef fish as having the same taste, while 36% rated Nile tilapia as tasting better. This is the only age group that had participants (9.1%) rating Nile tilapia as tasting worse than reef fish. This could be an indication that this group represents those that have developed their taste for reef fish. Nevertheless, almost 90% of this group rated Nile tilapia as having the same taste as reef fish and Nile tilapia tasting better.
The differences in taste between Nile tilapia and reef fish indicate that the majority preferred Nile tilapia because it is soft, tasty and fatty. Of the two people that ranked Nile tilapia as tasting worse than reef fish, one responded that tilapia is too soft.
It could be argued that the situation would be different if there was actually reef fish cooked in coconut cream for comparison. While this may have some truth, but the results clearly illustrates that, in the absence of reef fish, Nile tilapia is an acceptable substitute. It is believed that a major contributing factor is how the fish was prepared in that the “freshwater taste” was eliminated.
4.2 Nile Tilapia Cooked in a Samoan “umu”
The overall results of the survey where both Nile tilapia and reef fish were cooked in the Samoan “umu” and having people tasting both, indicated a slightly higher percentage (45.8) ranking reef fish as tasting better. However, a comparable percentage (41.7) ranked Nile tilapia as tasting better than reef fish, while 12.5% rated both Nile tilapia and reef fish as tasting the same. The fact that a comparable percentage actually rated Nile tilapia as tasting better than reef fish is a strong indication of the acceptability of Nile tilapia as a substitute for reef fish.
The preference for reef fish over Nile tilapia was higher in females than males. However, for males, there was an equal preference in which 43% rated Nile tilapia as tasting better and 43% rated reef fish as tasting better while the remaining 14% rated both fish as tasting the same. This again indicates that females are more sensitive and that they take very little risk in areas of this nature.
As is the case with fish cooked in coconut cream, the youngest age group, 6–15 years of age, was poorly represented with only 5 participants in this survey. A relatively high percentage (60) of this group ranked Nile tilapia as tasting better than reef fish while the rest ranked reef fish as tasting better. Again it can be argued that this age group represents those that have not yet developed specific tastes for fish. The 16–25 years old group was represented by 13 participants and the highest portion (46.2%) rated Nile tilapia as having a better taste, while about 39% rated reef fish as tasting better with 15.4 per cent rating both fish as having the same taste. The 26–35 years old group had the highest representation in this survey, having 23 participants. Different from the results of the other survey in this study, the highest portion in this group rated tilapia as tasting better than the reef fish species tasted. This again is an indication that these groups have not yet fully developed their taste for fish. The vast majority (about 69 per cent) of the 36–45 years old group rated reef fish as tasting better than tilapia with only 25% preferring tilapia over reef fish. The majority (about 54%) of 46+ years old group also rated reef fish as tasting better than tilapia. As was aid before, this group represents those that have developed fish tastes and tend to prefer the “usual”. However, fair proportions of these groups actually rated tilapia better.
The differences in taste between Nile tilapia and reef fish indicate that the majority recognised that Nile tilapia flesh was softer than that of reef fish. However, of the total 22 that claimed that tilapia flesh was soft, 41% rated this as a positive characteristic, 41% also rated this a negative while 18% ranked them as the same. The second major taste difference was that reef fish was salty. Thirteen people noted this difference of which 10 (77%) rated this as a positive characteristic. The third main taste difference was that reef fish was firm. Only seven people of the total 67 participants noted this difference and of these 7, 5 rated this as a positive characteristic while the other two put as a negative one. Only two participants recognised smell as a difference, and one put it as a positive characteristic while the other one put it as negative.
When the date was sorted according to the reef fish species used for comparative tasting, it was indicated that preference for reef fish was affected by the reef fish species used. People placed their preference for reef fish when the more popular reef fish species, such as “alogo” (lined surgeonfish), “malau” (squirrelfish/soldierfish), “pone” (bristle tooth surgeonfish) and “mataeleele” (emperorfish), were being tasted against Nile tilapia. However, tilapia was equally preferred as other popular reef fish such as “lupo” (trevally) and “taulaia/vete” (goatfishes). Nile tilapia was mostly preferred over the common reef fish “fuga/ulapo” (parrotfishes).
As stated earlier, this study was different from the previous study in that reef fish species were used for comparative taste test and that tasters knew or were informed that the “new” fish being tested was Nile tilapia.
The overall results of the survey for Nile tilapia cooked in coconut cream without actually having reef fish for “on-the-spot” comparative tasting, shows that in the absence of reef fish, Nile tilapia is a well acceptable substitute, on the same level as reef fish. This applies to both sexes and across all age groups as only 4.7% of the respondents declared Nile tilapia as having a worse taste than reef fish while 95.3%t ranked Nile tilapia as tasting better or having the same taste as reef fish.
The overall conclusion from the survey using Nile tilapia and reef fish cooked in a Samoan “umu” also shows that Nile tilapia is acceptable as a food fish on the same level as reef fish. Even though there was a slightly more proportion preferring reef fish but the fact that a comparable percentage actually rated Nile tilapia as tasting better than reef fish is a strong indication of the acceptability of Nile tilapia on the same level as reef fish. Female participants seem to be more sensitive to sources of fish (i.e. fresh-water or marine) than male participants. Higher proportions of the younger participants, aged 6 to 35 years prefer Nile tilapia over reef fish whereas the majority of those aged 36+ years preferred reef fish over tilapia.
It is also concluded that particular reef fish species affected the results. People placed their preference for reef fish when the more popular species, such as “alogo” (lined surgeonfish), “malau” (squirrelfish/soldierfish), “pone” (bristle tooth surgeonfish) and “mataeleele” (emperorfish), were being tasted against Nile tilapia. However, tilapia was equally preferred as other popular reef fish species such as “lupo” (trevally) and “taulaia/veta” (goatfishes). Nile tilapia was preferred over the common reef fish “fuga/ulapo” (parrotfishes).
Nile tilapia, cooked in the most common traditional methods of cooking fish in Samoa is well accepted on the same level as reef fish provided salt is satisfactorily applied.
As far as acceptance of Nile tilapia as a food fish is concerned, the results clearly show that creating alternative fish production for consumption and as a source of income, using Nile tilapia, is a very viable venture in Samoa. This in turn will divert pressure from the over-exploited nearshore fishery resources.
Fisheries Division, Samoa, would like to thank the FAO SPADP (II) for providing Nile tilapia specimens from Fiji for the study. Mr Ueli O'Brien, Faafouina Fuli and “gang” were responsible for cooking all the fish. Mr Tulaga Malaulau assisted in conducting the survey.
