title: Enhancement of "flavours" through enzymatic release of glutamate

authors: Juwono, Joshua

abstract: The sensory characteristics of food, in particular the flavours of food, play a very crucial role in the food industry. It is often what consumers associate most from food, and it is therefore crucial for food manufacturers like The Tatua Co-operative Dairy Company to produce flavour ingredients that are unique and of the highest quality.  
The Dairy Flavour Ingredients Business Unit at Tatua produces a range of dairy flavour ingredients including Butter, Cream and Milk, and Cheese Flavours. Tatua exports most of their flavour products worldwide to various food manufacturers, enhancing the flavour of the products that such manufacturers produce. Umami or savouriness is one of the five primary tastes. It is one of the most important flavour characteristic in dairy flavourings. In particular, umami is most needed in many of the different cheese flavourings produced by Tatua.  
This project focuses on optimising the release of glutamate from casein. Liberated glutamate with a commercial name HCP337 is used as a flavour enhancer, increasing the umami of the dairy flavourings that Tatua makes. Alternatively, the addition of monosodium glutamate (MSG) can also increase the umami of the flavours that Tatua makes, however this is not possible due to a couple of reasons: MSG has a negative reputation in the consumers’ mind, as many believe consumption of MSG can cause negative health effects; another reason is that addition of MSG would prevent Tatua from labelling their products as “natural”. Thus, the glutamate used for Tatua’s flavour ingredients is derived from the proteolysis of casein.  
Currently, the problem is that very little free glutamate is present in the HCP337 product even after a very long proteolysis. Therefore, the purpose of this project is to comprehensively examine the biochemistry of glutamate release in order to find the optimum proteolysis condition and use this knowledge to optimise the current process, increasing glutamate release. 
Three techniques were developed over the initial part of the study to quantify glutamate, glutamine, and pyroglutamic acid. A thorough set of samples from the HCP337 production process were then characterised. We found that indeed there was low glutamate content in the HCP337 product, and there was pyroglutamic acid in significant amounts. Stability tests of both glutamate and glutamine showed that glutamate is stable and not affected by the processing conditions. On the other hand, glutamine is very unstable and converted into pyroglutamic acid spontaneously under the processing conditions.  
With this information, various tests were performed with the focus of maximising glutamate yield from casein. These tests included: testing the proteolytic capacity of new and different enzymes at differing pH values with the hope of finding a better and more suitable enzyme at liberating glutamate from casein, the use of different acidifying agents in the HCP337 production process, and the screening of glutaminase activity within the new enzymes. The presence of glutaminase may further increase the glutamate yield, as glutaminase will convert the free glutamine released into glutamate instead of it spontaneously forming pyroglutamic acid. 
In summary, this study demonstrated that the current HCP337 production process is not designed to optimally release glutamate from casein. Altering the pH and enzyme combinations during hydrolysis did not appear to be effective strategies to increase glutamate release from casein. More tests on more enzyme should be conducted in the future in order to find enzymes that are most effective at releasing glutamate under the appropriate production process.

text: Enhancement of "flavours" through enzymatic release of glutamate The sensory characteristics of food, in particular the flavours of food, play a very crucial role in the food industry. It is often what consumers associate most from food, and it is therefore crucial for food manufacturers like The Tatua Co-operative Dairy Company to produce flavour ingredients that are unique and of the highest quality.  
The Dairy Flavour Ingredients Business Unit at Tatua produces a range of dairy flavour ingredients including Butter, Cream and Milk, and Cheese Flavours. Tatua exports most of their flavour products worldwide to various food manufacturers, enhancing the flavour of the products that such manufacturers produce. Umami or savouriness is one of the five primary tastes. It is one of the most important flavour characteristic in dairy flavourings. In particular, umami is most needed in many of the different cheese flavourings produced by Tatua.  
This project focuses on optimising the release of glutamate from casein. Liberated glutamate with a commercial name HCP337 is used as a flavour enhancer, increasing the umami of the dairy flavourings that Tatua makes. Alternatively, the addition of monosodium glutamate (MSG) can also increase the umami of the flavours that Tatua makes, however this is not possible due to a couple of reasons: MSG has a negative reputation in the consumers’ mind, as many believe consumption of MSG can cause negative health effects; another reason is that addition of MSG would prevent Tatua from labelling their products as “natural”. Thus, the glutamate used for Tatua’s flavour ingredients is derived from the proteolysis of casein.  
Currently, the problem is that very little free glutamate is present in the HCP337 product even after a very long proteolysis. Therefore, the purpose of this project is to comprehensively examine the biochemistry of glutamate release in order to find the optimum proteolysis condition and use this knowledge to optimise the current process, increasing glutamate release. 
Three techniques were developed over the initial part of the study to quantify glutamate, glutamine, and pyroglutamic acid. A thorough set of samples from the HCP337 production process were then characterised. We found that indeed there was low glutamate content in the HCP337 product, and there was pyroglutamic acid in significant amounts. Stability tests of both glutamate and glutamine showed that glutamate is stable and not affected by the processing conditions. On the other hand, glutamine is very unstable and converted into pyroglutamic acid spontaneously under the processing conditions.  
With this information, various tests were performed with the focus of maximising glutamate yield from casein. These tests included: testing the proteolytic capacity of new and different enzymes at differing pH values with the hope of finding a better and more suitable enzyme at liberating glutamate from casein, the use of different acidifying agents in the HCP337 production process, and the screening of glutaminase activity within the new enzymes. The presence of glutaminase may further increase the glutamate yield, as glutaminase will convert the free glutamine released into glutamate instead of it spontaneously forming pyroglutamic acid. 
In summary, this study demonstrated that the current HCP337 production process is not designed to optimally release glutamate from casein. Altering the pH and enzyme combinations during hydrolysis did not appear to be effective strategies to increase glutamate release from casein. More tests on more enzyme should be conducted in the future in order to find enzymes that are most effective at releasing glutamate under the appropriate production process.

year: 2016

title: Dynamic landscape, dynamic practice: Aboriginal dwelling beside the Carran Carran–Durt’yowan floodplains (Thomson River–Latrobe River, Central Gippsland)

authors: Anderson, William

abstract: Recurring occupation beside waterways is an essential part of Aboriginal dwelling and movement in the landscape. Riverbanks and their wider floodplains were repeatedly inhabited as hunting and fishing grounds and to gather plants and other materials; moreover, Aboriginal people used rivers and creeks as routeways and landmarks to navigate Country, for meetings and ceremonies, to affirm boundaries and territorial claims; and they were sacred features whose origins were captured in stories and songs. Archaeological investigations often encounter material that hints at persistent occupation of riverine landforms, but it is rare to conclusively prove the overall duration that a place was inhabited and the length of occupation episodes. Excavations near Sale in central Gippsland, in GunaiKurnai Country, identified one such place. Cultural deposits buried in the sands of an alluvial rise at Fulham include hearths and concentrations of stone artefacts up to a metre deep. Radiocarbon dating shows two distinct occupation phases—in the Late Pleistocene and Holocene eras—that were separated by a gap of up to eight thousand years. The results underline the enduring significance of the alluvial plains around the confluence of Carran Carran (Thomson River) and Durt’yowan (Latrobe River) and show habitation by GunaiKurnai Ancestors over vast timespans as the climate, water level, landforms and ecology of the wider estuarine district changed. They highlight spatial and temporal connections between the upper and lower reaches of these river systems over several millennia, giving a unique, long–term perspective on human responses to shifts in climate and water flows.

text: Dynamic landscape, dynamic practice: Aboriginal dwelling beside the Carran Carran–Durt’yowan floodplains (Thomson River–Latrobe River, Central Gippsland) Recurring occupation beside waterways is an essential part of Aboriginal dwelling and movement in the landscape. Riverbanks and their wider floodplains were repeatedly inhabited as hunting and fishing grounds and to gather plants and other materials; moreover, Aboriginal people used rivers and creeks as routeways and landmarks to navigate Country, for meetings and ceremonies, to affirm boundaries and territorial claims; and they were sacred features whose origins were captured in stories and songs. Archaeological investigations often encounter material that hints at persistent occupation of riverine landforms, but it is rare to conclusively prove the overall duration that a place was inhabited and the length of occupation episodes. Excavations near Sale in central Gippsland, in GunaiKurnai Country, identified one such place. Cultural deposits buried in the sands of an alluvial rise at Fulham include hearths and concentrations of stone artefacts up to a metre deep. Radiocarbon dating shows two distinct occupation phases—in the Late Pleistocene and Holocene eras—that were separated by a gap of up to eight thousand years. The results underline the enduring significance of the alluvial plains around the confluence of Carran Carran (Thomson River) and Durt’yowan (Latrobe River) and show habitation by GunaiKurnai Ancestors over vast timespans as the climate, water level, landforms and ecology of the wider estuarine district changed. They highlight spatial and temporal connections between the upper and lower reaches of these river systems over several millennia, giving a unique, long–term perspective on human responses to shifts in climate and water flows.

year: 2021

title: A study of iwi communication between Te Tau Ihu iwi and intergenerational diasporic whānau

authors: Wright, Karamea Moana

subjects: diaspora

abstract: This study looks at the online communication methods used between Te Tau Ihu iwi and intergenerational uri who live in the diaspora. Preferences and perceptions of methods of communication utilized by both iwi, and tāngata who live in the overseas diaspora were explored. Most important are the implications for uri living away from Aotearoa, and their desire to remain connected to iwi in New Zealand. This is a mixed methods study, comprising of a survey of fifty-eight emigrant respondents living abroad, and interviews with one member of the first, second, and third generations of emigrants to the United States, with affiliation to at least one of the eight tribes who claim tāngata whenua status of Te Tau Ihu.

The implications of the findings from the study provide both iwi and tāngata the opportunity to create a synergistic relationship of communicating. Assisting iwi to develop and implement a strategy for relevant communication, and iwi members engaging in a dialogue with iwi about relevance of communication is critical in strengthening ties between iwi and future generations regardless of location. “He aha te mea nui, he tangata, he tangata.”

text: A study of iwi communication between Te Tau Ihu iwi and intergenerational diasporic whānau This study looks at the online communication methods used between Te Tau Ihu iwi and intergenerational uri who live in the diaspora. Preferences and perceptions of methods of communication utilized by both iwi, and tāngata who live in the overseas diaspora were explored. Most important are the implications for uri living away from Aotearoa, and their desire to remain connected to iwi in New Zealand. This is a mixed methods study, comprising of a survey of fifty-eight emigrant respondents living abroad, and interviews with one member of the first, second, and third generations of emigrants to the United States, with affiliation to at least one of the eight tribes who claim tāngata whenua status of Te Tau Ihu.

The implications of the findings from the study provide both iwi and tāngata the opportunity to create a synergistic relationship of communicating. Assisting iwi to develop and implement a strategy for relevant communication, and iwi members engaging in a dialogue with iwi about relevance of communication is critical in strengthening ties between iwi and future generations regardless of location. “He aha te mea nui, he tangata, he tangata.”

year: 2019