The Potential of Guava Leaf Extract as A Natural Preservation for Fish

Fish is kinds of food that easy to spoil. High protein content in fish makes the food is a good medium for microorganisms. People commonly buy fish for consumption, however, not all fish are consumed at the same time. Fishes were stored in freezer for several days or preserved with additional chemical preservation. The use of organic preservatives have no harm. This paper discussed guava (Psidium guajava L) leave as natural fish preservation. The objectives were to analyze the potency of the leaves as a natural preservation for mackerel fish (Rastrelliger sp.). Fime parameters used to determine the fish quality as follows : gills, eye, texture, odour and mucilage. The treatments were leaf methanolic extract with doses 0, 20, 40, 60 and 80%. Data were taken on from 1 to 5 days after storage. The results showed that (i) Fish quality was decline and start to depraved at 2 day storage, especially at control treatment (0% extract). Treatment at doses 60 and 80%, the fish quality were still relatively good over 3 days storage. Even though the fish samples have been starting spoilage, those fishes were still available to be consumed. At the same time, with the other treatment, the fish samples have been spoiled and no more available to be consumed. However, at 5th day of storage, all samples at all treatments were spoiled. Overall results, it can be concluded that extract of guava leaves can be has as fish preservative. Keyword: dosage, extract , guava leaves, mackerel fish Received 8 November 2019 | Revised 25 December2019 | Accepted 26 January2020

preservation such as salt change the taste. Cahyono [3] mentioned the use of natural preservations such as bay-leaves (Syzygium polyanthum), betle leaves (Piper betle) and orange extraction.
This paper examine guava leave (Psidium guajava) as natural for fish preservation. Psidium guajava has been used in traditional medicine in many cultures throughout Central America, the Caribbean, Africa, and Asia [4]. People uses common guava for food and herbal. There are estimated, more than 150 species of guava in the world [5]. According to Rattanachaikunsopon et al, [6], the leaves of P. guajava contain the flavonol morin, morin-3-O-lyxoside, morin-3-Oarabinoside, quercetin and quercetin-3-O-arabinoside. Heuzé et al , [7] mentioned that guava was an edible fruit and can be eaten raw or cooked. The processing of the fruits yields byproducts that can be fed to livestock. It is very useful to our health. The leaves can also be used as fodder. According to Sudarsono et al. [8] common guava leaf contains flavonoid, tannin (17.4 %), fenolic (575.3 mg/g) and eteris oil.
One of fish species that is commonly consumed is mackerel fish. The fish is an important that is consumed worldwide. According to FAO Fact Sheet [9] the mackerel fish have deeply forked tails and are smaller and slimmer than tuna. The mackerel is spoils rapidly, especially in the tropics. Traditional commonly used to preservee fish include drying, salting, pickling and smoking. Modern techniques also used such as of freezing and canning those have taken on a large importance [10]. Croker et al. [11] explained that mackerel is an important food fish that is consumed worldwide since hundred years ago. Many fisheries were traditionally pickled mackerel with large amounts of salt, which allowed it to be sold widely. The purpose of this study was to analyze guava (Psidium guajava L.) leaves as a fish natural preservation. until 9 (high/good quality) via physical condition using score-sheet. The score were as follow:

Materials and Methods
Score (1 -9) and physical criteria of fish quality.

Fish parameter
Criteria and specific quality Score Eye  Bright eye, stick-out pupils, white cornea.  Slightly bright eye, slightly brown pupil, white cornea  Concave eye, browned pupil, turbid cornea.  Very concave pupil, yellow cornea

Result and Discussion
The results, scoring of physical fish quality from observation of 5 parameter in which each parameter in 1 replicates were shown in Table 1. The range of score is from 9 (high/good quality) to 1 (low/poor quality). The effect of guava leaf extract to mackerel fish preservation with parameter of eye is presented in Figure 1. Guava leaf extract on concentration 60% and 80%, in 4 th day preservation, the score of fish quality, still in score 3. On the other hand, the other treatments (0%, 20% and 60%), the quality score of fish had been decreasing at 1, that means the fish samples had been completely spoilage. The effect of guava leaf extract to mackerel fish preservation with parameter of gills is presented in Figure 2. preservation, has score of fish quality l around 3. Treatment with concentration 80% in 4 th day has score 4 (the fish is still available to be consumed) and at 5 th day preservation has score 4. At day 4 the control treatments (0%), the quality score of fish had been decreasing at below score 2, that means the fish samples had been spoilage. This results indicate that common guava leaf extract has a potency to be used for preservation of fish.
The effect of guava leaf extract to mackerel fish preservation with parameter of Aroma is presented in Figure 3. Graph 3 shows on 4 th days preservation, the quality score of fish with treatments, 20, 40, 60 and 80%, all gave higher that score on control (0%). Treatment with concentration 80% at 5 th day preservation has score 3 and the other treatments have been decreased on score 1.
The effect of guava leaf extract to mackerel fish preservation with parameter of texture is presented in Figure 4. preservation, has score of fish quality on around 3. Treatment with concentration 80% in 4 th day has score 4 (the fish is still available to be consumed) and at 5 th day preservation has score 4.
On the other hand, the control treatments (0%), the quality score of fish had been decreasing at 1, that means the fish samples had been completely spoilage. Figure 4 indicate again, that common guava leaf extract potential to be used for fish preservation.
The effect of guava leaf extract to mackerel fish preservation with parameter of mucilage is presented in Figure 5. Guava leaf extract on concentration 20, 40, 60 and 60%, at 4 th day preservation, has score quality on around 3. Treatment with concentration 80% in 3 rd , 4 th and 5 th day has score higher that score on control (0%). The result showed that guava leaf extract has a potency to be used to preserve fish. Based on data on Figure 1, 2, 3, 4 and 5 was averaged, therefore, it will be able to see at Figure   6 showed prediction of Y = 5.

Acknowledgement
We would like to thank to Abdul Karim for technical assistance