THE EFFECT OF REPEATED FREEZING-THAWING ON QUALITY OF TUNA FISH BALLS

Abu Bakar Jiwo Seto¹, Nurfitri Ekantari¹, Prihati Sih Nugraheni^1*

¹Department of Fisheries, Faculty of Agriculture,Gadjah Mada University, Yogyakarta, Indonesia

^*Corresponding author: nugrahenips@ugm.ac.id 

This study aims to determine the effect of repeated freezing-thawing on the quality of tuna fish balls. The research used fish balls with freezing-thawing cycles of 1 to 6. Determination of the cycle is based on the habits of retailers in traditional markets that sell the fish ball without refrigeration and freeze it again if they are not sold out up to 3 times. In this research, the number of cycles was made more to determine the safety limit of fish balls for consumption. The analysis that was carried out in this study includes the temperature of the center and surface of the fish ball, drip loss, the number of bacteria, total volatile base, texture with Lloyd's method, sensory, and proximate test. Repeated freezing-thawing was shown to decrease the quality of the texture and sensory (appearance, smell, and taste) of fish balls, while the drip loss increased with the increasing number of freezing-thawing cycles. The TPC and TVB values exceed the safe consumption limit in the 4^th freezing-thawing cycle so that the freezing-thawing process should not exceed 3 times. The results of the proximate analysis showed that the nutritional value also decreased when freezing-thawing was carried out in 4 cycles compared to the initial condition (0 cycle). This research is expected to be used to educate fish ball retailers and consumers to more pay attention to how to handle the products sold.

Keywords: Cycle, Fish ball, Freezing, Quality, Thawing

THE MUSCLE ORGANIZATION OF EPISESARMA SINGAPORENSE, AS AN IMPORTANT SEARMA CRAB FROM THAILAND

Phimolnard Chomchuen^1,*, Pornthep Wirachwong¹, Supparat Kong-Oh¹, Wannee Jiraungkoorskul², Gen Kaneko³, Sinlapachai Senarat¹, Supapong Imsonpang ⁴,

Atsuo lida⁵, Chanyut Sudtongkong¹

¹Department of Marine Science and Environment, Faculty of Science and Fisheries Technology, Rajamangala University of Technology Srivijaya, Trang, Thailand Agriculture ²Department of Anatomy, Faculty of Medical Science, Naresuan University, 65000 Thailand ³College of Natural and Applied Science, University of Houston-Victoria, Victoria, Texas, USA

⁴Division of Health and Applied Sciences, Faculty of Science, Prince of Songkla Univerity, Songkhla 90110, Thailand

⁵Department of Animal Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan

^*Corresponding author: phimolnard41.pc@gmail.com

The muscle structure has been investigated in many crabs in relation to their growth and development; however, such information has not been covered in E. singaporense. In this study, we investigated the muscle histology of E. singaporense using the morphometric analysis between different areas (Area 1: abdomen, Area 2: Cheliped and Area 3: working leg). Thirty muscle fibers from each area were measured. It was clear that the organization of E. singaporense skeleton was tightly packed, showing the striated muscle in longitudinal sections. Within the muscle, the muscle fibers contained several myofilaments. Multiple peripherally located nuclei were visible in the muscle fiber, and the muscle fiber ran through the entire length of the actual muscle. According to the morphometric data, all muscular areas were differed. Our results suggested that the Area 1 of E. singaporense skeleton would be where the highest muscle mass growth takes place and is suitable for crab meat consumption.

Keywords: Histology, Muscular organization, Searma crab, Thailand

POTENTIAL APPLICATION OF NATURAL HYDROXYAPATITE (HAp) DERIVED FROM FISHERY BY-PRODUCTS IN ECO-FRIENDLY TOOTHPASTE FORMULATION

Nor Fazliyana Mohtar^1*, Mohamad Rais Hassan¹, Habibah Hamzah¹, Mohd Sabri Mohd Ghazali ²

¹Faculty of Fisheries and Food Science, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia

²Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia

*Corresponding author email: fazliyana@umt.edu.my 

Toothpaste formulation development has become vital due to dental health problems. There has been series of improvements in the formulation including the incorporation of synthetic fluoride and microbeads. However, the existing problems of the current toothpaste formulation are caused due to the synthetic fluoride and its toxicity issues on consumer health. Therefore, there is a rising concern to address such problems through the development of environmental-friendly hydroxyapatite (HAp) toothpaste extracted from fishery by-products. This study was aimed to extract a natural hydroxyapatite (HAp) from several types of fishery by-products via calcination at series of temperatures and to characterize their physico-chemical properties as compared to the standard HAp. Results have confirmed that the extracted HAp demonstrated better properties than that of observed in standard HAp. The heating profile of the extracted HAp possessed the highest inflection point at a temperature range from 400°C to 800°C. The morphological analysis has demonstrated smaller particle size distribution observed in extracted HAp compared to the standard HAp. Similar findings were also observed on the Ca/P ratio of the extracted HAp, which was identical to that of the standard HAp, as well as the crystallinity phase that matched with the standard peak. The FTIR analysis have confirmed the presence of phosphate, hydroxyl and water molecule groups observed in the extracted HAp. Overall results have successfully revealed the potential properties of HAp extracted from fishery by-products and their future prospect in substituting the existing synthetic HAp. Such findings could also create a significant demand for HAp in vast applications to meet the global requirements for Halal and Kosher markets, thus contributing to a better and safe environment.

Keywords: Hydroxyapatite, Fisheries, By-Products, Toothpaste, Formulation

THE EFFECT OF SUBSTITUTING WHEAT FLOUR WITH A COMBINATION OF MILKFISH BONE FLOUR (CHANOS CHANOS) AND SEAWEED FLOUR (KAPPAPHYCUS ALVAREZII) ON THE CHARACTERISTICS OF DRIED NOODLES

Insiyah Rizqiyanah¹, Mochammad Amin Alamsjah^2*, and Dwi Yuli Pujiastuti²

¹Study Program of Fish Processing Technology, Faculty of Fisheries and Marine, Universitas Airlangga, Indonesia

²Department of Marine, Faculty of Fisheries and Marine, Universitas Airlangga, Indonesia

*E-mail: alamsjah@fpk.unair.ac.id

The raw material used in the processing of dried noodles is wheat flour. Indonesia is not a country that produces wheat as a raw material for wheat flour. The use of wheat flour can be reduced by substituting it using milkfish bones and seaweed (Kappaphycus alvarezii) which is abundant in Indonesia. Substituting wheat flour with these ingredients is also needed to increase the nutritional content of dried noodles. This study aims to determine the effect of substituting wheat flour with a combination of milkfish bone flour and seaweed flour (K. alvarezii) on the sensory and chemical characteristics of dried noodles. The study was experimental using a Complete Random Design (RAL) with four treatments and five repeats. The treatment in this study was a combination of milkfish bone flour and seaweed (K. alvarezii) (0%, 10%, 20% and 30%) of the amount of wheat flour. Organoleptic test analysis uses the Kruskal-Wallis test and Mann-Whitney test, while chemical tests use Paired Sample T-Test test. The results showed that there was a significant effect (P<0.05) on the sensory and chemical characteristics of dried noodles. The best sensory test results are on dried noodles with a 10% substituting milkfish bone flour and seaweed flour (K. alvarezii) (P1). Dried noodles (P1) have chemical characteristics of 7.21% water content, 9.40% ash, 10.03% crude protein, 1.18% crude fat, 5.75% crude fiber, 66.41% crude carbohydrates, and 3.53% calcium.

Keywords: Dried noodles, substitution, milkfish bone flour, seaweed flour, Kappaphycus alvarezii

QUALITY INDEX METHOD SCHEMES FOR SENSORY EVALUATION OF FRESH/CHILLED POMPANO (Trachinotus blochii)

Nga T. T. Mai^1,*, Van A. Huynh¹, Sa T. Le^,2

¹Faculty of Food Technology Nha Trang University, No 2 Nguyen Dinh Chieu Street, Nha Trang City, Viet Nam

²Center for Experiments and Practices, Nha Trang University, No 2 Nguyen Dinh Chieu Street, Nha Trang City, Viet Nam

^*Corresponding author: ngamtt@ntu.edu.vn

Pompano (Trachinotus blochii) belongs to the Carangidae family. The new commercial species has become more and more economically important for Vietnam and needs a convenient tool to evaluate its freshness or quality. Quality index method (QIM) is a sensory assessment mean developed for specific species and products, considered advantageous over other organoleptic methods thanks to its simplicity, accuracy, uniqueness, and predictability of chilled seafood shelf life. Each scheme composes of various attributes with 0-1, 0-2 or 0-3 demerit points and a total score or quality index (QI) linearly correlated with storage time. In this study, two separate QIM schemes were established, one for chilled whole pompano and another for chilled fillets. The earlier contains 9 descriptors, namely, Skin; Mucus; Texture of the fish back; Texture of the fish belly; Odor; Eye brightness; Eye shape; Gill color and Gill odor with a total score of 0-19. The later consists of the following attributes: Color; Color; Mucus of fillet side and of fillet side; and Texture with a maximal QI 13. The schemes were tested to monitor the freshness of whole and fillet pompano during storage at 0-2 and/or 2-4 °C. The results show that the QI increased linearly with storage days at coefficients of determinations of 0.68-0.86, therefore, the schemes need further improvement.

Keywords: Pompano, Quality index method, Chilled storage, Freshness, Shelf life

PREVENTION OF LIPID OXIDATION IN DRIED ROUND SCAD FILLETS BY USING NATURAL ANTIOXIDANT-CONTAINING EXTRACT FROM VOI LEAF (Cleistocalyx operculatus)

Xuan Duy Nguyen*, Thi My Hanh Tran

Nha Trang University, No. 2 Nguyen Dinh Chieu Street, Nha Trang City, Vietnam

^*Corresponding author: duynx@ntu.edu.vn

Lipid oxidation is one of the most important deterioration in lipid-rich food. Marine fish is rich in lipid with a lot of polyunsaturated fatty acids. These fatty acids are very susceptible to oxidation process. Therefore, deteriorations related to lipid oxidation are one of the major sources that occur during production, storage, distribution and consumption. One of the most effective ways of retarding lipid oxidation in foods is to incorporate.  In this study, we investigated to apply a natural antioxidant-containing extract extracted from Voi’s leaves grown in Vietnam to retard lipid oxidation in dried round scad fillets. Accordingly, the Voi’s leaves were extracted at an optimal condition to obtain maximum polyphenol content, including a temperature of  70^oC, time of 100 mins, a solvent extract of ethanol 60%, a ratio of solvent and material of 60/1 (v/w). Polyphenol-containing extract was partly purified using a solvent system with an increasing polarity. The highest polyphenol content was found in the water fraction. This polyphenol-rich extract was evaluated antioxidant activity using free radical scavenging ability (ABTS) and reducing power ability (RPA), retardation of lipid oxidation in oil-in-water model system. Finally, the polyphenol-rich extract was applied in preventing lipid oxidation in dried round scad fillets. Results showed that the polyphenol-rich extract from the Voi’s leaves exhibited antioxidant activity in all of tests in vitro. A value of IC50 of ABTS and RPA were 2.97 µg/ml and 5.01 µg/ml. In oil-in-water model system, the polyphenol-rich extract at 200 ppm prevented effectively lipid oxidation compared with the control sample. Dried round scad fillets were treated by the polyphenol-rich extract indicated a significant reduction of lipid oxidation level as shown by conjugated diene index, peroxide value, and thiobarbituric acid reaction substances. These values of the extract-treated fillets were significantly lower than those of the control samples (p < 0.05).

Keywords: Cleistocalyx operculatus, dried round scad fillets, lipid oxidation, natural antioxidant.