title: Osmotic Dehydration of Selected Commercial Crops

authors: Pontawe, Reagan Jazmin

subjects: Dehydration

abstract: Osmotic dehydration can partially reduce the moisture content of most fruits and vegetables. This method was applied to New Zealand chestnuts and Philippine cassava. The effect of osmotic dehydration on mass transfer kinetics (water loss, solids gain and normalized moisture content) and quality of osmosed products were investigated. Shelled (i.e. shell removed) and unshelled (i.e. shell intact) chestnuts in bulk conditions (1kg samples) were immersed in sodium chloride, sucrose, glucose and calcium chloride solutions of 15, 22; 50, 60; 56.5 and 50 % (w/w), respectively for 2, 4, 6, 8, 10 up to 24 hours. Cassava slices with 15 mm thickness in bulk condition (1kg samples) were immersed in sodium chloride and sucrose solutions of 22 and 25; 60% (w/w), respectively for 30, 60, 90, 120, 150, 180 and 210 minutes. The solution to product ratio was kept above 10 to minimise the concentration change of the osmotic solutions during the dehydration experiments. Experiments were conducted at ambient conditions.
For chestnuts, using glucose (56.5% w/w) and calcium chloride (50% w/w) solutions produced unfavourable results. The normalised moisture content for both shelled and unshelled chestnuts using 22% (w/w) sodium chloride and 60% (w/w) sucrose solutions was reduced to about 75 and 80%, respectively after 8 hours at 20.5°C. Thus, the chestnut shell was not a significant barrier during osmotic dehydration with these solutions. Water loss rates were higher compared to solids’ gain values both for shelled and unshelled chestnuts. The optimum osmotic dehydration time for shelled and unshelled chestnuts was 6-8 hours. Furthermore, using sodium chloride (22% w/w), the recovery of wholenuts after mechanical shelling (i.e. shell removal) showed a statistically significant improvement from 28.5±0.04% (unosmosed) to around 45.3±0.04% (osmosed). In addition, with a different batch of chestnuts, using sucrose (60% w/w) solution, an improvement of almost 16.5±.08% (osmosed) from the control (unosmosed) on wholenuts shelling recovery achieved. Chestnuts osmosed with 22% (w/w) sodium chloride were darker compared to the control samples while chestnuts osmosed with 60% (w/w) sucrose was no colour difference to unosmosed chestnuts. However, chestnuts osmosed with sucrose were more brittle than unosmosed chestnuts.
For chipped cassava the optimum osmotic dehydration time was found to be 210 minutes for 25% (w/w) sodium chloride and 180 minutes for 60% (w/w) sucrose. The sodium chloride (25% w/w) solution achieved a slightly higher moisture loss compared to that of sucrose (60% w/w) solution at 24.5°C. After osmotic dehydration, air drying was done for final drying (to a moisture content of 0.13, wet basis) of the chipped cassava. The optimum drying temperature was 70°C at 1.8 m/s air velocity. Drying rate was not affected significantly by osmotic solutions and osmosed cassava was not affected by a 10°C increase in the drying temperature. Osmosed products with 25% (w/w) sodium chloride or 60% (w/w) sucrose showed no gelatinization after air drying to 70°C. Cassava osmosed with 60% (w/w) sucrose was darker compared to samples osmosed with 25% (w/w) sodium chloride and to unosmosed, air dried chipped cassava.
If a chestnut processor’s aim is to get higher wholenuts recovery after mechanical shelling, a 6 hour osmotic dehydration period using 22% (w/w) NaCl is recommended. Otherwise, if the processor prefers good shelling recovery and considers the broken nuts to be used for second stage by-products processing (e.g. crumb, chestnut flour), 8-hour osmotic dehydration time before mechanical shelling is more advantageous.
Osmotic dehydration for chipped cassava using 25% (w/w) sodium chloride and 60% (w/w) sucrose is only effective up to 210 and 180 minutes, respectively. The optimum air drying temperature for osmosed cassava chips with no gelatinization effect was 70°C

text: Osmotic Dehydration of Selected Commercial Crops Osmotic dehydration can partially reduce the moisture content of most fruits and vegetables. This method was applied to New Zealand chestnuts and Philippine cassava. The effect of osmotic dehydration on mass transfer kinetics (water loss, solids gain and normalized moisture content) and quality of osmosed products were investigated. Shelled (i.e. shell removed) and unshelled (i.e. shell intact) chestnuts in bulk conditions (1kg samples) were immersed in sodium chloride, sucrose, glucose and calcium chloride solutions of 15, 22; 50, 60; 56.5 and 50 % (w/w), respectively for 2, 4, 6, 8, 10 up to 24 hours. Cassava slices with 15 mm thickness in bulk condition (1kg samples) were immersed in sodium chloride and sucrose solutions of 22 and 25; 60% (w/w), respectively for 30, 60, 90, 120, 150, 180 and 210 minutes. The solution to product ratio was kept above 10 to minimise the concentration change of the osmotic solutions during the dehydration experiments. Experiments were conducted at ambient conditions.
For chestnuts, using glucose (56.5% w/w) and calcium chloride (50% w/w) solutions produced unfavourable results. The normalised moisture content for both shelled and unshelled chestnuts using 22% (w/w) sodium chloride and 60% (w/w) sucrose solutions was reduced to about 75 and 80%, respectively after 8 hours at 20.5°C. Thus, the chestnut shell was not a significant barrier during osmotic dehydration with these solutions. Water loss rates were higher compared to solids’ gain values both for shelled and unshelled chestnuts. The optimum osmotic dehydration time for shelled and unshelled chestnuts was 6-8 hours. Furthermore, using sodium chloride (22% w/w), the recovery of wholenuts after mechanical shelling (i.e. shell removal) showed a statistically significant improvement from 28.5±0.04% (unosmosed) to around 45.3±0.04% (osmosed). In addition, with a different batch of chestnuts, using sucrose (60% w/w) solution, an improvement of almost 16.5±.08% (osmosed) from the control (unosmosed) on wholenuts shelling recovery achieved. Chestnuts osmosed with 22% (w/w) sodium chloride were darker compared to the control samples while chestnuts osmosed with 60% (w/w) sucrose was no colour difference to unosmosed chestnuts. However, chestnuts osmosed with sucrose were more brittle than unosmosed chestnuts.
For chipped cassava the optimum osmotic dehydration time was found to be 210 minutes for 25% (w/w) sodium chloride and 180 minutes for 60% (w/w) sucrose. The sodium chloride (25% w/w) solution achieved a slightly higher moisture loss compared to that of sucrose (60% w/w) solution at 24.5°C. After osmotic dehydration, air drying was done for final drying (to a moisture content of 0.13, wet basis) of the chipped cassava. The optimum drying temperature was 70°C at 1.8 m/s air velocity. Drying rate was not affected significantly by osmotic solutions and osmosed cassava was not affected by a 10°C increase in the drying temperature. Osmosed products with 25% (w/w) sodium chloride or 60% (w/w) sucrose showed no gelatinization after air drying to 70°C. Cassava osmosed with 60% (w/w) sucrose was darker compared to samples osmosed with 25% (w/w) sodium chloride and to unosmosed, air dried chipped cassava.
If a chestnut processor’s aim is to get higher wholenuts recovery after mechanical shelling, a 6 hour osmotic dehydration period using 22% (w/w) NaCl is recommended. Otherwise, if the processor prefers good shelling recovery and considers the broken nuts to be used for second stage by-products processing (e.g. crumb, chestnut flour), 8-hour osmotic dehydration time before mechanical shelling is more advantageous.
Osmotic dehydration for chipped cassava using 25% (w/w) sodium chloride and 60% (w/w) sucrose is only effective up to 210 and 180 minutes, respectively. The optimum air drying temperature for osmosed cassava chips with no gelatinization effect was 70°C

year: 2013

title: Federalism and resource conflict: Assessing the impact of federalism in curbing conflict over petroleum resource revenues - A case study of Nigeria and Canada

authors: Kalu, John Otisi

subjects: Federalism

abstract: This thesis focuses on lingering conflict over natural resource revenues which has ravaged many countries. The problem has no doubt attracted the attention of researchers who have approached it, mostly, from the angle of how natural resources lead to violent and armed conflict; impact of natural resource conflict on economic growth; causes and the factors that increase the intensity of the conflict. Regrettably, the preoccupation of researches on those other aspects of resource conflict as mentioned, results in the unfortunate dearth of research that focus on charting out the means to bring about solutions to the problem. This study therefore argues that genuine solution to resource conflict can come from a specific design of the political institution of government—precisely, the institutionalization of federalism in the given country. 
However, the case of the Nigerian federation suggests the contrary, with conflict over resource revenues getting increasingly strident. It was therefore deemed vital to undertake a comparative case study of the problem in Nigeria and another federal country – Canada, in order to ascertain the extent to which federalism can contribute to resolve resource conflict. In-depth interviews were conducted with selected respondents in Nigeria and Canada to complement the secondary data from extant literature. The ‘method of difference’ was employed in the analysis of data which aided the identification of significant differences that account for variations in the manifestation of conflict over resource revenues across the countries. 
After the analysis, this study makes two major discoveries that contribute to the existing scholarship on the subject as follows. Firstly, findings from the case of Nigeria reveal that factors inhibiting federalism in mitigating resource conflict are linked primarily to a huge influence of oil and gas on the economy, or over dependence on the resource to drive the economy. The research illustrates clearly how this factor leads to excessive fiscal centralization, which undermines subnational fiscal autonomy, heightens poverty, enables ambiguous design of the fiscal constitution, and facilitates widespread corruption and non-adherence to the rule of law; all of which enhances the severity of resource conflict. Secondly, findings from the Canadian case illustrate how the reinforcement of sub-national fiscal autonomy, which is the hallmark of federalism, counteracts the above mentioned effects of over dependence on petroleum resources. This consequently reduces the violent manifestation of resource conflict. 
With some illustrative diagrams built to support arguments, the study concludes that the institution of federalism provides an effective means through which resource conflict can be addressed. This study provides lessons that would no doubt be useful to, not only Nigeria and Canada but also, many other natural resource endowed countries that are still battling problems of resource revenue dispositions. More so, the analysis in this thesis should be of interest to scholars of conflict and resource governance in deeply divided societies, students of federalism and multilevel governance, as well as policy makers and analysts interested in the facilitation of unity through diversity in their respective countries of focus.

text: Federalism and resource conflict: Assessing the impact of federalism in curbing conflict over petroleum resource revenues - A case study of Nigeria and Canada This thesis focuses on lingering conflict over natural resource revenues which has ravaged many countries. The problem has no doubt attracted the attention of researchers who have approached it, mostly, from the angle of how natural resources lead to violent and armed conflict; impact of natural resource conflict on economic growth; causes and the factors that increase the intensity of the conflict. Regrettably, the preoccupation of researches on those other aspects of resource conflict as mentioned, results in the unfortunate dearth of research that focus on charting out the means to bring about solutions to the problem. This study therefore argues that genuine solution to resource conflict can come from a specific design of the political institution of government—precisely, the institutionalization of federalism in the given country. 
However, the case of the Nigerian federation suggests the contrary, with conflict over resource revenues getting increasingly strident. It was therefore deemed vital to undertake a comparative case study of the problem in Nigeria and another federal country – Canada, in order to ascertain the extent to which federalism can contribute to resolve resource conflict. In-depth interviews were conducted with selected respondents in Nigeria and Canada to complement the secondary data from extant literature. The ‘method of difference’ was employed in the analysis of data which aided the identification of significant differences that account for variations in the manifestation of conflict over resource revenues across the countries. 
After the analysis, this study makes two major discoveries that contribute to the existing scholarship on the subject as follows. Firstly, findings from the case of Nigeria reveal that factors inhibiting federalism in mitigating resource conflict are linked primarily to a huge influence of oil and gas on the economy, or over dependence on the resource to drive the economy. The research illustrates clearly how this factor leads to excessive fiscal centralization, which undermines subnational fiscal autonomy, heightens poverty, enables ambiguous design of the fiscal constitution, and facilitates widespread corruption and non-adherence to the rule of law; all of which enhances the severity of resource conflict. Secondly, findings from the Canadian case illustrate how the reinforcement of sub-national fiscal autonomy, which is the hallmark of federalism, counteracts the above mentioned effects of over dependence on petroleum resources. This consequently reduces the violent manifestation of resource conflict. 
With some illustrative diagrams built to support arguments, the study concludes that the institution of federalism provides an effective means through which resource conflict can be addressed. This study provides lessons that would no doubt be useful to, not only Nigeria and Canada but also, many other natural resource endowed countries that are still battling problems of resource revenue dispositions. More so, the analysis in this thesis should be of interest to scholars of conflict and resource governance in deeply divided societies, students of federalism and multilevel governance, as well as policy makers and analysts interested in the facilitation of unity through diversity in their respective countries of focus.

year: 2016

title: When your maunga is a mountain but your moana is not a sea; Insights from the perception of synonymy of te reo Māori loanwords and New Zealand English lexical equivalents

authors: Pohl, Alexander

abstract: Languages and their speakers are in ongoing contact with one another, which inevitably leads to a flow of words being borrowed from one language into another (Haspelmath 2009; Winford 2010). One perspective that has comparatively seen less attention in language contact research concerns how loanword relate to existing lexical alternatives. In recent years, language contact research has thus seen a paradigm shift towards an onomasiological perspective (see Anderson et al. 2017; Crombez et al. 2022; Zenner et al. 2023). Within this shift, most studies looking at lexical variation between loanwords and their near synonyms equivalents employ corpus linguistics methods (e.g. Onysko & WinterFroemel 2011; Soares da Silva 2013). 

This project presents a large-scale experimental approach from a case-study involving Māori loanwords borrowed into New Zealand English (NZE). Māori loanwords are ubiquitous, salient and probably still increasing within the NZE lexicon (Macalister 2007; Trye et al. 2019). Regarding onomasiology, Māori loanwords have been glossed and explained in different ways, and to date, there has been to our knowledge almost no research focused specifically on the relationship between loanwords and their near synonyms. 

Here, we report on a Qualtrics experiment devised to probe the perceived relationship between 60 Māori loanwords (spanning established semantic categories: flora and fauna, material culture, and social culture) and their NZE equivalents, as ascertained from published sources. The synonymy judgments were elicited for pairs (e.g. whānau – family), using an analogue slider (ranging from 0 = non-synonymous to 100 = fully synonymous; see Figure 1). Because synonymy judgements are subjective, we also included ten fillers, to help us calibrate and interpret participant judgements. The 60 words were divided into two-word lists in order avoid fatigue, resulting in a within participant design. The target demographic for our population of interest consisted of young adults (18-24 years). 

Following cleaning and exclusions (e.g. participants who ignored filler items), the final dataset contained 260 participants. Inspecting the dataset showed a skew towards female participants, and for this reason, we focus our statistical analysis on this core sample, while keeping an eye on the full dataset containing all participants. Preliminary findings suggest that young adults think Māori loanwords are (highly) synonymous with NZE lexical alternatives. These findings will be further scrutinised with regression techniques and qualitative analyses of the comments provided in an open answer section of the questionnaire.

text: When your maunga is a mountain but your moana is not a sea; Insights from the perception of synonymy of te reo Māori loanwords and New Zealand English lexical equivalents Languages and their speakers are in ongoing contact with one another, which inevitably leads to a flow of words being borrowed from one language into another (Haspelmath 2009; Winford 2010). One perspective that has comparatively seen less attention in language contact research concerns how loanword relate to existing lexical alternatives. In recent years, language contact research has thus seen a paradigm shift towards an onomasiological perspective (see Anderson et al. 2017; Crombez et al. 2022; Zenner et al. 2023). Within this shift, most studies looking at lexical variation between loanwords and their near synonyms equivalents employ corpus linguistics methods (e.g. Onysko & WinterFroemel 2011; Soares da Silva 2013). 

This project presents a large-scale experimental approach from a case-study involving Māori loanwords borrowed into New Zealand English (NZE). Māori loanwords are ubiquitous, salient and probably still increasing within the NZE lexicon (Macalister 2007; Trye et al. 2019). Regarding onomasiology, Māori loanwords have been glossed and explained in different ways, and to date, there has been to our knowledge almost no research focused specifically on the relationship between loanwords and their near synonyms. 

Here, we report on a Qualtrics experiment devised to probe the perceived relationship between 60 Māori loanwords (spanning established semantic categories: flora and fauna, material culture, and social culture) and their NZE equivalents, as ascertained from published sources. The synonymy judgments were elicited for pairs (e.g. whānau – family), using an analogue slider (ranging from 0 = non-synonymous to 100 = fully synonymous; see Figure 1). Because synonymy judgements are subjective, we also included ten fillers, to help us calibrate and interpret participant judgements. The 60 words were divided into two-word lists in order avoid fatigue, resulting in a within participant design. The target demographic for our population of interest consisted of young adults (18-24 years). 

Following cleaning and exclusions (e.g. participants who ignored filler items), the final dataset contained 260 participants. Inspecting the dataset showed a skew towards female participants, and for this reason, we focus our statistical analysis on this core sample, while keeping an eye on the full dataset containing all participants. Preliminary findings suggest that young adults think Māori loanwords are (highly) synonymous with NZE lexical alternatives. These findings will be further scrutinised with regression techniques and qualitative analyses of the comments provided in an open answer section of the questionnaire.

year: 2024