Development of Tenderized Fermented Squid Product in the Form of Spread and Pieces Using Kiwifruit Protease Priyanka Chacko A thesis submitted to AUT University in partial fulfillment of the requirements for the degree of Master of Applied Science (MAppSc) June 2016 School of Science Auckland University of Technology Table of Contents Table of Contents ................................................................................................................. i List of Figures ..................................................................................................................... iii List of Tables ...................................................................................................................... iv Acknowledgement .............................................................................................................. v Abstract ............................................................................................................................. vi Statement of Originality ................................................................................................... viii Chapter 1 ............................................................................................................................ 1 Introduction ........................................................................................................................ 1 Fermentation and fermented foods .............................................................................................................................. 1 History of fermentation .......................................................................................................................................................... 1 Traditional and industrial fermentations ..................................................................................................................... 2 Microorganisms involved in fermentation .................................................................................................................... 3 Classification of fermented foods ................................................................................................................................... 5 Fermentation producing a meat-like textured food ................................................................................................. 5 High-salt savoury-flavoured amino acid/peptide sauces and pastes ............................................................... 6 Alcoholic fermentations ......................................................................................................................................................... 6 Acetic acid/vinegar fermentations ................................................................................................................................... 7 Alkaline fermentations ........................................................................................................................................................... 7 Lactic acid fermentation ........................................................................................................................................................ 8 Fermented meat products ...................................................................................................................................................10 Fermented fish and seafood products ............................................................................................................................11 Squid ....................................................................................................................................................................................... 13 Major squid products .............................................................................................................................................................14 Tenderization of squid ..........................................................................................................................................................15 The New Zealand squid industry ......................................................................................................................................17 Objectives of the study .................................................................................................................................................... 18 Chapter 2 .......................................................................................................................... 19 Product development with minced squid ........................................................................... 19 Introduction ......................................................................................................................................................................... 19 Materials and Methods .................................................................................................................................................... 20 Equipment, chemicals and starter culture ..................................................................................................................20 Fermented squid mince preparation..............................................................................................................................20 Analysis by inspection ...........................................................................................................................................................22 Measurement of pH ................................................................................................................................................................22 Measurement of colour .........................................................................................................................................................22 Texture analysis of minced fermented squid ..............................................................................................................22 Data analysis for this and later chapters .....................................................................................................................23 Results and discussion ..................................................................................................................................................... 23 Pilot trial .....................................................................................................................................................................................23 Formal trial ................................................................................................................................................................................25 Conclusion ............................................................................................................................................................................ 27 Chapter 3 .......................................................................................................................... 28 Development of various forms of fermented squid ............................................................ 28 Introduction ......................................................................................................................................................................... 28 Materials and Methods .................................................................................................................................................... 28 Preparation of bowl chopped treatments ....................................................................................................................30 i Preparation of sliced squid treatments.........................................................................................................................30 pH, colour and texture analysis ........................................................................................................................................30 Results and Discussion .................................................................................................................................................... 31 Conclusion ............................................................................................................................................................................ 35 Chapter 4 .......................................................................................................................... 36 Microscopy ....................................................................................................................... 36 Introduction ......................................................................................................................................................................... 36 Materials and methods .................................................................................................................................................... 36 Light microscopy .....................................................................................................................................................................36 Electron microscopy ..............................................................................................................................................................36 Results ...................................................................................................................................................................................