Study on the application of liquid ice for handling and preservation of yellowfin tuna

MINISTRY OF EDUCATION AND TRAINING NHA TRANG UNIVERSITY OLANREWAJU AKIN YINKA STUDY ON THE APPLICATION OF LIQUID ICE FOR HANDLING AND PRESERVATION OF YELLOWFIN TUNA MASTER THESIS KHANH HOA - 2020 MINISTRY OF EDUCATION AND TRAINING NHA TRANG UNIVERSITY OLANREWAJU AKIN YINKA STUDY ON THE APPLICATION OF LIQUID ICE FOR HANDLING AND PRESERVATION OF YELLOWFIN TUNA MASTER THESIS Major: Food Technology Code: 8540101 Topic allocation Decision 192/QĐ-ĐHNT dated 03/3/2020 Decision on establishing the Committee: 899/QĐ-ĐHNT dated 04/9/2020 Defense date: 18/9/2020 Supervisors: Dr Mai Thị Tuyết Nga Chairman: Assoc Prof Nguyen Thuan Anh Department of Graduate Studies: KHANH HOA - 2020 ii UNDERTAKING I undertake that the thesis entitled: “Study on the application of liquid ice for handling and preservation of yellowfin tuna” is my own work The data collection was an effort of a research team led by my supervisor, Dr Mai Thi Tuyet Nga, who started the project KC.05.10/16-20 of Vietnam “Studying, designing, and manufacturing a liquid ice production system for handling and preservation of ocean tuna” since April 2018 before I began my MSc study in Vietnam I joint the project since January 2020, when the final phase of the project studying on slurry ice and crushed block ice was going on, and luckily allowed to use the data previously collected by my teammates The work has not been presented elsewhere for assessment until the time this thesis is submitted Khanh Hoa, date 25 month 08 year 2020 Author Olanrewaju Akin Yinka iii ACKNOWLEDGMENTS First and for most, my sincere appreciation goes to God for granting me such a great opportunity to be alive and healthy to complete this program I specially honor the Lord Jesus and the Holy Spirit for the deep inspiration, supernatural strength, and great opportunity made available to be awarded a scholarship in Vietnam Secondly, I really want to appreciate my supervisor and promoter in the person of Dr Mai Tuyet Nga for her unrelenting supports and great contributions towards the success of this research study I acknowledge the support of the HOD, secretary of the program and other staff in the department Thirdly, I would like to express the deepest appreciation to my good friend for his immense contribution towards the success of my thesis My good colleagues, you are well appreciated for your love and kindness Especially, I appreciate my family and friends in the diaspora for your love, prayers, and support I would like to appreciate the support of the VLIR Network Vietnam, Nha Trang University, Food Technology Department for the success of this research study Food Technology Laboratories at Nha Trang University for allowing me to carry out this research study with their up-to-date equipment Last but not least, I would like to thank project KC.05.10/16-20 of Vietnam “Studying, designing, and manufacturing a liquid ice production system for handling and preservation of ocean tuna” for financial support and permission to use its data for my MSc thesis iv ABSTRACT Yellowfin tuna (Thunnus albacares) is a big species of tuna mostly found in Atlantic, Pacific and Indian oceans It is an important aspect of tuna fisheries worldwide and in the major oceans, yellowfin tuna is one of the major target species for the tuna fishery and the most commonly catch marine fish on overseas fishery The major objective of this study was to evaluate the suitable handling and preservation methods that could be used for port-harvested Yellowfin tuna Among the studied cooling and storage media, the liquid ice of 3.5% NaCl, 48% ice content, initial temperature of 4.0°C showed the best preservation effect for yellowfin tuna sensory quality The second most effective medium was the liquid ice of 3.0% NaCl, 44% ice content, initial temperature of -3.1°C Fish chilled down either in slurry ice of initial temperature of -4.0°C or in crushed ice, and then stored in crushed ice had the second worst and the worst sensory quality, respectively, indicating the weakness of traditional icing However, no cooling or storage media effect, as well as no size influence on TVC of tuna samples has been found so far These results vividly showed that liquid/slurry ice has a large scope of preservation effect and has the potential to improve significantly the quality and as well as extends the product shelf life Further study on on-board cooling and salt uptake of fish stored for long period in liquid ice is needed v TABLE OF CONTENTS UNDERTAKING iii ACKNOWLEDGMENTS iv ABSTRACT v TABLE OF CONTENTS LIST OF ABBREVIATIONS LIST OF FIGURES LIST OF TABLES CHAPTER INTRODUCTION 1.1 INTRODUCTION 1.2 MAIN OBJECTIVE 1.3 SPECIFIC OBJECTIVES 1.4 PROBLEM STATEMENTS CHAPTER LITERAURE REVIEW 11 2.1 YELLOWFIN TUNA 11 2.1.1 Production 11 2.1.2 Habitat of Yellowfin Tuna 12 2.1.3 Size, age, and growth 12 1.3.4 Reproduction 13 2.2 POST-MORTEM QUALITY CHANGES OF FISH-RELEVANT FACTORS AND VARIABLES 14 2.2.1 Autolytic changes 14 2.2.2 Chemical spoilage 14 2.2.3 Microbiological spoilage 15 2.3 HANDLING AND PRESERVATION OF FISH 16 2.4 REFRIGERATED METHODS OF SEAFOOD PRESERVATION 18 2.4.1 Icing and iced storage of fish 21 2.4.2 Pre-cooling and cooling by slurry ice 22 2.5 EVALUATION OF FRESHNESS AND QUALITY CHANGES OF FISH 24 2.5.1 Sensory analysis 25 2.5.2 Microbiological analysis 27 CHAPTER MATERIALS AND METHODS 28 3.1 MATERIALS 28 3.2 APPARATUS AND TOOLS 28 3.3 METHODS 29 3.3.1 Experimental plan 29 3.3.2 Experimental factors 30 3.3.3 Sampling 30 3.3.4 Determination of sensory quality 32 3.3.5 Determination of total viable count 33 3.4 DATA COLLECTION AND ANALYSIS 34 CHAPTER RESULTS AND DISCUSSION 35 4.1 CHANGES OF TVC IN TUNA DURING STORAGE OF FISH 35 4.1.1 Changes of TVC in tuna cooled and stored in liquid ice over time 35 4.1.2 Changes of TVC in tuna cooled in ice slurry and stored in crushed block ice 40 4.1.3 Changes of TVC in tuna cooled and stored in crushed block ice 41 4.2 SENSORY CHANGES OF TUNA DURING STORAGE 43 4.2.1 Sensory changes of tuna cooled and stored in liquid ice over time 43 4.2.2 Sensory changes of tuna cooled in ice slurry and stored in crushed block ice 47 4.2.3 Sensory changes of tuna cooled and stored in crushed block ice 48 4.2.4 Comparison of sensory quality of yellowfin tuna cooled and stored in different media 49 CONCLUSIONS AND RECOMMENDATIONS 58 CONCLUSIONS 58 RECOMMENDATIONS 58 REFERENCES 59 APPENDICES - - LIST OF ABBREVIATIONS °C – Degree Celsius CFU - Colony forming unit F - Fish g - Gram Kg – Kilogram NaCl - Sodium Chloride TVC - Total viable count LIST OF FIGURES Figure Experimental flowchart 29 Figure Yellowfin tuna 31 Figure Sampling tool 31 Figure 3 Procedures of TVC determination 33 Figure Changes of TVC of Fish (30 kg up) during storage in liquid ice of 3.0% of NaCl, 44% initial ice concentration, and initial temperature of -3.1°C 35 Figure Changes of TVC in Fish (20 kg up) during storage in liquid ice of 3.5% of NaCl, 48% initial ice concentration, and initial temperature of -4.0 °C 37 Figure Changes of TVC in Fish (30 kg up) during storage in liquid ice of 3.5% of NaCl, 48% initial ice concentration, and initial temperature of -4.0°C 38 Figure 4 Changes of TVC in Fish (40 kg up) during storage in liquid ice of 3.5% NaCl, 48% initial ice concentration, and initial temperature of -4.0°C 39 Figure Changes of TVC in Fish (30 kg up) cooled in ice slurry with an initial temperature of -4.0°C and stored in crushed block ice 40 Figure Sensory changes of Fish (30 kg up) stored in liquid ice of 3.0% NaCl, 44% initial ice mass, and initial temperature of -3.1°C 43 Figure Sensory changes of Fish (30 kg up) cooled in ice slurry with an initial temperature of -4.0°C and stored in crushed block ice 47 Figure Comparison of the sensory quality of all the fish at day 49 Figure Comparison of the sensory quality of all the fish at day 50 Figure 10 Comparison of the sensory quality of all the fish at day 51 Figure 11 Comparison of the sensory quality of all the fish at day 51 Figure 12 Comparison of the sensory quality of all the fish at day 12 52 Figure 13 Comparison of the sensory quality of all the fish at day 15 53 Figure 14 Comparison of the sensory quality of all the fish at day 18 54 Figure 15 Comparison of the sensory quality of all the fish at day 21 54 Figure 16 Comparison of the sensory quality of all the fish at day 24 55 Figure 17 Comparison of the sensory quality of all the fish at day 27 56 Figure 18 Comparison of the sensory quality of all the fish at day 30 56 LIST OF TABLES Table Studied parameters of liquid ice 30 Table Cooling and storage media for tuna 30 Table 3 Control sensory sheet 32 Table Changes of TVC in Fish (40 kg up) cooled and stored in crushed block ice 41 Table Changes of TVC in Fish (30 kg up) cooled and stored in crushed block ice 42 Table Sensory scores of Fish (20 kg up) cooled and stored in liquid ice of 3.5% NaCl, 48% initial ice concentration, and initial temperature of -4.0°C 45 Table 4 Sensory scores of Fish (40 kg up) and Fish (30 kg up) cooled and stored in crushed block ice 48 From day 15 onward, there were only fish left, which were Fish 2-Fish 5, and Fish (quickly cooled by liquid ice or slurry ice) since control samples (Fish and Fish 7, cooled by crushed ice) spoilt completely and were excluded from further quality evaluation Color Odor Meat texture A A Scores A A AB C AB B B B B AB AB BC C F2 F3 F4 Fish F5 F8 Figure 13 Comparison of the sensory quality of all the fish at day 15 Notes: Results are means ± standard deviations For each attribute, values with different letters are significantly different (p < 0.05) On day 15 (Figure 13), the colour of Fish (stored in liquid ice of 3.0% NaCl, 44% ice concentration, initial temperature of -3.1°C) and Fish (stored in crushed ice) became significantly worse (p < 0.05) compared to Fish and Fish 4, which were stored in liquid ice of 3.5% NaCl, 48% ice concentration, initial temperature of 4.0°C The odour of Fish was more defective (p < 0.05) than Fish and Fish The meat texture of Fish changed significantly (p < 0.05) in comparison with Fish and Fish 53 Scores Color Odor A Meat texture A A A AB AB BC BC C B C C F2 F3 B B BC F4 F5 F8 Fish Figure 14 Comparison of the sensory quality of all the fish at day 18 Notes: Results are means ± standard deviations For each attribute, values with different letters are significantly different (p < 0.05) Color Scores A Odor Meat texture A A A A AB AB AB B B B B B B B F2 F3 F4 Fish F5 F8 Figure 15 Comparison of the sensory quality of all the fish at day 21 Notes: Results are means ± standard deviations For each attribute, values with different letters are significantly different (p < 0.05) 54 The fish could be grouped based on sensory quality from day 18 to day 24 (Figure 14-Figure 16) The first group composed of Fish 3, Fish 4, and Fish 5, cooled and stored in liquid ice of 3.5% NaCl, 48% ice concentration, initial temperature of 4.0°C, has the best remaining quality The second group was Fish 2, stored in liquid ice of 3.0% NaCl, 44% ice concentration, and initial temperature of -3.1°C The last group was Fish 8, cooled in slurry ice with initial temperature of -4.0°C, which had Scores the worst sensory quality Color A Odor Meat texture A A A A AB B C F2 AB B B BC C F3 B B F4 F5 F8 Fish Figure 16 Comparison of the sensory quality of all the fish at day 24 Notes: Results are means ± standard deviations For each attribute, values with different letters are significantly different (p < 0.05) At the later stage of storage (days 27-30, Figure 17-Figure 18), when the spoilage of all the fish became evident, the first group still had better sensory characteristics than the remaining ones 55 12 Color 10 Scores Meat texture A A Odor B A B C AB AB B C A C C C C F2 F3 F4 F5 F8 Fish Figure 17 Comparison of the sensory quality of all the fish at day 27 Notes: Results are means ± standard deviations For each attribute, values with different letters are significantly different (p < 0.05) 10 Color Scores Meat texture A A Odor AB AB C B BC B C A B C A AB ABC F2 F3 F4 F5 F8 Fish Figure 18 Comparison of the sensory quality of all the fish at day 30 Notes: Results are means ± standard deviations For each attribute, values with different letters are significantly different (p < 0.05) 56 To sum up, among the studied cooling and storage media, the liquid ice of 3.5% NaCl, 48% ice concentration, initial temperature of -4.0°C showed the best preservation effect for yellowfin tuna sensory quality The second most effective medium was the liquid ice of 3.0% NaCl, 44% ice concentration, initial temperature of -3.1°C Fish chilled down either in slurry ice of initial temperature of -4.0°C or in crushed ice, and then stored in crushed ice had the second worst and the worst organoleptic quality, respectively The findings support the advantage of liquid ice over the other environments in fish handling and storage to retain the product quality 57 CONCLUSIONS AND RECOMMENDATIONS CONCLUSIONS Among the studied cooling and storage media, the liquid ice of 3.5% NaCl, 48% ice content, initial temperature of -4.0°C showed the best preservation effect for yellowfin tuna sensory quality The second most effective medium was the liquid ice of 3.0% NaCl, 44% ice content, and initial temperature of -3.1°C Fish chilled down either in slurry ice of initial temperature of -4.0°C or in crushed ice, and then stored in crushed ice had the second worst and the worst sensory quality, respectively, indicating the weakness of traditional icing However, no cooling or storage media effect, as well as no size influence on TVC of tuna samples has been found so far RECOMMENDATIONS To have more solid supportive proof on the superior cooling and preservative effect of liquid ice on yellowfin tuna, further studies are recommended as follows: - Study with more replications; - Study on on-board cooling the fish, right after catch; - Study on the salt uptake of fish stored for 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5.3±1.2 A 21 5.3±0.6 AB 4.7±2.1BCD 5.3±0.6 A 24 5.7±0.6A 6.0±1.7ABC 5.7±0.6 A 27 5.7±0.6 A 6.3±2.1 ABC 5.7±0.6 A 30 6.0±0.0 A 7.7±0.6 AB 5.7±0.6 A 33 6.0±1.0 A 7.7±0.6AB 5.7± 0.6 A 36 6.0±0.0 A 8.0±1.0 AB 6.0±0.0 A 39 6.0±0.0 A 8.3±1.2A 6.0±0.0 A Notes: Results are means ± standard deviations In a column, values with different letters are significantly different (p < 0.05) Day = Start of storage Table A2 Sensory scores of Fish (30 kg up) cooled in ice slurry with an initial temperature of -4.0°C and stored in crushed block ice Storage time (days) Color Odor Meat texture -2 1.3±0.5EF 1.0±0F 1.0±0D -1 1.3±0.5EF 1.3±0.5F 1.3±0.5D 1.3±0.5EF 1.3±0.5F 1.3±0.5D -1- 0.8±0.5F 1.5±2.0F 2.0±2.0CD 1.3±0.5EF 1.0±0F 2.0±0CD 2.0±0DEF 2.5±0.6EF 1.8±0.5CD 12 3.0±0.8DE 3.8±0.5DE 3.3±1.3CD 15 3.5±1.0CD 4.5±1.7CDE 4.0±0.8BC 18 5.3±0.6BC 5.0±1.0BCD 7.0±1.0A 21 5.3±0.5BC 6.0±1.4ABC 6.0±1.4AB 24 6.0±0.8AB 6.5±1.3ABC 7.5±0.6A 27 8.0±1.7A 7.0±0AB 7.7±0.6A 30 7.5±1.0A 8.0±0.8A 8.0±0A Notes: Results are means ± standard deviations In a column, values with different letters are significantly different (p < 0.05) Day -2: Arrival to the laboratories; Day -1: Start of cooling; and Day 0: Start of storage Table A3 Comparison of the sensory quality of Fish and Fish at day 10 Fish Color Odor Meat texture F6 4.5± 1.0A 5.5±1.3A 5.8±1.5A F7 4.5±1.5A 5.5±1.9A 7.3±2.7A Notes: Results are means ± standard deviations In a column, values with different letters are significantly different (p < 0.05) Table A4 Comparison of the sensory quality of Fish and Fish at day 11 Fish Color Odor Meat texture F6 5.0±1.6A 5.5±1.0A 5.8±2.2A F7 4.5±1.3B 5.0±0.8A 5.5±1.7A Notes: Results are means ± standard deviations In a column, values with different letters are significantly different (p < 0.05) -2- ...MINISTRY OF EDUCATION AND TRAINING NHA TRANG UNIVERSITY OLANREWAJU AKIN YINKA STUDY ON THE APPLICATION OF LIQUID ICE FOR HANDLING AND PRESERVATION OF YELLOWFIN TUNA MASTER THESIS Major:... Department of Graduate Studies: KHANH HOA - 2020 ii UNDERTAKING I undertake that the thesis entitled: ? ?Study on the application of liquid ice for handling and preservation of yellowfin tuna? ?? is... development of bacteria, consequently spoilage is kept at minimum (Tawari and Abowei, 2011) Therefore, the aim of this study is to show the difference and the effect of ice slurry and block ice on the