This research project was designed to investigate the chemical and physical changes in pork pies during storage. Lipid oxidation and moisture migration were found to be the parameters of most importance, with protein cross-linkaging and colour changes in the meat filling "'having' less of a deteriorative effect on pie shelf life. The extent of lipid oxidation and the development of rancidity (taste and odour) were found to be affected by cooking, the age of the meat and back fat in the meat filling and by their storage conditions (temperature and time). An increase in all or any of these parameters was found to increase the rate of rancidity development. On the other hand the rusk and the seasoning mix used in the meat filling of the pies, were found to reduce the rate of rancidity development. This antioxidant activity was investigated further. In the rusk, substances produced by the maillard browning reaction during the course of its manufacture were found to be antioxidative. However prolonged heating, although it produced a rusk with high antioxidant activity, had lowered its water binding capacity sufficiently to prevent its use in the meat products where water has to be bound to an inert filler. The antioxidant component of the seasoning mix was found to be white pepper, with the ethanol soluble fraction exhibiting this activity. Lipid analyses showed that rancidity developed parallel to the loss of the unsaturated fatty acids which had a chain length of 16 or above carbon atoms; and a concomitant rise in the concentration of short chain fatty acids and aldehydes, especially those having five and six carbon atoms in the chain length. The level of hexanoic acid (C6: 0) rose as rancidity developed, being development most marked in the pies with the fastest rate of rancidity development (i. e. those devoid of both the rusk and the seasoning mix). Moistture migration, both from. the atmosphere and from the jelly into the pastry (especially into the brown outer layer of pastry) resulted in an increase in moisture content, and a decrease in texture, of the pastry. Threshold levels for these two parameters were established above and below which respectively the pastry was deemed unacceptable, and these values were used subsequently in the investigation to assess the effect of various products on shelf life extension. Simultaneous lowering of the relative humidity (r. h. ) of the external atmosphere, and lowering of the jelly aw to levels at which to prevent moisture migration into the pastry resulted in a 35 day shelf life for the pies. However the use of glycerol to reduce the jelly aw to 0.56 resulted in an unpleasant taste to the pie. Lowering the jelly aw to 0.84 gave an extension (of at least 2 days) to the usual 8 days shelf life. Unfortunately attempts to achieve this aw (0.84) by the use of binders and pfi, were unsuccessful. Similarly the use of cetyl alcohol as a moisture barrier within the pork pie was not effective. The formation of a gelatin-lactein cogel, showed excellent potential for reducing moisture migration in pork pies.

The Rice Krispies™ process consists essentially of the cooking of short or medium rice grains, followed by a mechanical compression between two rolls (bumping), a tempering step and a toasting operation (puffing) which expands the grains into the finished product. The objectives of this project were to clarify which molecular phenomena take place inside the rice grains during the process and to facilitate the improvement and optimisation of the process parameters. The composition and gelatinisation behaviour of seven different raw rice varieties used either in the United States or the United Kingdom were studied. The glass transition of the cooked rice material was determined by dynamic mechanical thermal analysis (DMTA), which allowed each step of the process to be mapped onto a temperature / moisture content state diagram. The bumping step of the process and its effect on the various molecular entities present in the cooked rice were studied in details. Amylose was found to form complexes with the lipids present in the material during cooking, and these reinforced the cooked rice grain structure. One of the roles of the bumping could be to partially dislocate these amylose-lipid complexes to enable the rice grains expansion at the puffing step of the process. The bumping also reduced the molecular weight of amylopectin, which is thought to weaken the rice grains structure and improve the puffed grains expansion. The mill gap between the bumping rolls was the key factor determining the quality of the puffed product. The temperature at which the rice grains are bumped had a secondary influence on the quality of the puffed rice, within the range 26°C to 57°C. The RVA provided a very effective method to categorise post-bumped samples and could be a useful diagnostic tool in case of production problems. Evidence of physical ageing and moisture content equilibration during the tempering step was found. Physical ageing did not have a detectable effect on the expansion of the rice grains, while it was important that moisture content was equilibrated inside the grains to ensure a proper puffing. Finally, correlations were found between the puffed rice grains expansion and the post-bumped grains height recovery, which made it possible to predict the quality of the expanded grains from the characterisation of the post-bumped rice. Overall, the project is a good example of the application of general starch science concepts to the study of a specific industrial process.

The nutty and cereal aromas of new make malt whisky are important sensory characteristics of certain distillery malts of commercial value for blending; however there is a lack of understanding regarding the volatile congeners which contribute to these complex sensory characters. The work described in this thesis aimed to improve knowledge of the chemical origins of nutty and cereal aromas in immature spirit in order to aid process control of these characters during manufacturing. Two aroma extraction methods were compared; liquid-liquid extraction (LLE) using dichloromethane and solid-phase extraction (SPE) with LiChrolut EN sorbent. New make spirit samples from industry (n=S) were evaluated by a trained whisky sensory panel using Quantitative Descriptive Analysis (QDA). Four were noted for their nutty/cereal character, the other served as a non-nutty control. Gas Chromatography-Olfactometry/ Mass Spectrometry (GC-O/MS) was used to try and identify compounds in chromatogram regions coincident with nutty/cereal descriptors. Using LLE extracts, 14 such regions were identified. LiChrolut EN SPE proved to be more selective (19 nutty/cereal odour active regions). 2,S-dimethylpyrazine (known to impart a nutty/cereal character in other food systems) was one noted congener, which was only detected using the more selective SPE method. The gross volatile compositions of the 5 spirit samples were remarkably similar, suggesting that congeners present at low concentration but with low odour thresholds are likely responsible for nutty/ cereal characters. One analytical difference of note was that the nuttier samples contained higher concentrations of long-chain esters. Thus, ethanolic Atmospheric Pressure Chemical Ionisation Mass Spectrometry (APCI-MS) was used to analyse the headspace concentrations of a test set of 14 whisky aroma volatiles above a series of aqueous ethanolic solutions differing in concentrations of alcohol (5 -40% ABV) and ethyl hexadecanoate (O-SOO mg/L). Ethanol had a significant solubilising effect (p < 0.0001) on headspace volatile concentrations of all the aroma compounds, whilst the ethyl hexadecanoate concentration had a selective effect of reducing headspace concentrations of the more hydrophobic aroma compounds (Log P > 2.S). We propose that nutty and cereal characters are imparted by relatively polar aroma compounds, whose characters are emphasised by the selective incorporation of hydrophobic aroma compounds into the interior of micelle-like structures formed by long chain esters (typified here by ethyl hexadecanoate). Some distillers have reported that manipulation of the lipid concentrations in wash offers a method of controlling the nutty/oily character of new make spirit. A batch of fermented wash sourced from industry was spiked with varying concentrations of oleic (18:1) and linoleic (18:2) acids and (laboratory) distilled at two different temperatures, using a D-optimal experimental design to evaluate the impacts of each factor. Nutty (p = 0.0203) and oily (p = 0.0034) aroma characteristics were scored as significantly stronger in distillates of wash spiked with 100 Ilg/mL each of oleic and linoleic acids, as compared to the control. GC-O/MS of distillate extracts once again determined several odour active regions relevant to the nutty/cereal characters and concentrations of some compounds could be correlated with nutty/cereal QDA scores. New make spirit samples from 35 individual malt whisky distilleries were extracted using the LiChrolut SPE method and analysed by GC-MS. Analytical concentrations of 'candidate' nutty-cereal compounds (n = 20) were used to model sensory QDA data for the 35 spirit samples (nutty, oily, cereal and feinty characters) using Principal Components Analysis (PCA). Significant positive correlations with nutty were seen for 7 compounds (using ANOVA). These included the Maillard products 2-furanmethanol (p < 0.0001), 2-methylpyrazine (p < 0.0013) and 2,5-dimethylpyrazine (p < 0.0004). The PCA overlay bi -plot showed clustering of certain higher alcohols near to the nutty aroma descriptor (methionol, pentan-1-0I, 2-phenyethyl alcohol). Nutty and cereal characters of whisky are of complex origin and likely originate from multiple congeners in a synergistic mixture. This work has shown that processes of particular importance to the expression of this character in new make spirit are lipid oxidation and Maillard chemistry. The conditions for these reactions are to be found during malt kilning and distillation. Whilst these processes are where nutty/cereal compounds are likely to be formed, other distillery parameters such as the mashing protocol, length of fermentation (both determine the supply of key precursors such as fatty and amino acids) and the spirit cut of the distillation govern the chemical composition of the final spirit.

This work reports a fundamental study of the science and economics of microwave and RF drying of foods, addressing current knowledge gaps and introducing new techniques to aid the development of new microwave and RF drying processes. The present study has discovered that a correlation exists between the points of inflection of the moisture dependant dielectric properties and the moisture dependant water activity. Hence the moisture dependant dielectric properties are governed by the state of the water as defined by the sorption isotherms. Water activity equations were mathematically modified in this study to successfully describe moisture dependant dielectric properties. This is a valuable contribution to science as there are currently no recognised standard equations for describing the moisture dependence of dielectric properties. These new proposed equations are of great value as they can be used in microwave drying models. This will enable engineers to optimise microwave and RF processes, leading to a reduction in the trial and error approach that currently prevails in industry. Improved optimisation may ultimately lead to more successful microwave and RF applications. It is extremely important to be able to monitor key parameters such as porosity, oil and water content, when introducing a new food processing technique. To this end, a new and novel technique for quantifying the porosity of thin irregularly shaped food has been established. This can be used as a diagnostic tool to assess and optimise processing changes such as the introduction of new microwave or RF drying processes. A good understanding of how RF/MW processes affects porosity can be used to optimise the drying process, leading to a greater probability of success. Sorption isotherm measurements carried out in this study showed that the gelatinisation of starch in potato has a negligible effect on the isosteric heat of sorption. This is important for drying applications, as the isosteric heat of sorption is very significant compared to the latent heat at low moisture contents. Dielectric properties were measured for potato crisps, biscuits, and pasta particulate at 915MHz, and were used to gain new insights into moisture levelling behaviour through analytical analysis. Contrary to common belief, it was found that moisture levelling can be more effective below the critical moisture content, at lower moisture contents. Although moisture levelling limits the variability of the final moisture content, it was found that fine control of the final moisture content can only be achieved by minimising variation in electric field exposure. Feasibility studies of microwave applications showed that finish drying microwave applications were far more practical and cost effective compared to applications that have to remove large quantities of water. Dry food is generally quite thin so that it is eatable, or for rehydration purposes. As a consequence conventional food drying processes tend to be sufficiently energy efficient so that even microwave and RF finish drying processes are comparatively expensive with respect to energy usage. Hence, microwave and RF food drying must be justified by improvements in quality.

It is well known that in English law the indemnity insurers stand in a better position than the assureds and this is especially true when a claim is delayed: in that scenario, the insurer is neither liable for the damage caused by the late payment, nor for the compound interest. In Sprung v. Royal Insurance ([1999] 1 Lloyd's Rep IR 111) this unfair situation was justified by the Court of Appeal, naturally, it brought an opportunity for the Law Commission to reconsider the law. Recently, the new Insurance Act 2015 has been enacted and subsequently amended by the Enterprise Act 2016 in regards to the insurer’s obligation to make a timely payment; however, the legal effect of the new legislation is unknown due to the lack of binding precedents. In this work, the duty of the indemnity insurer shall be discussed in full and this work will try to make a contribution to the interpretation of the new legislation regarding to the obligation of the insurer and remedies for the assured.

Whilst there is a tradition of indigenous opaque sorghum beer production in Africa, the manufacture of Western-style clarified lager beers from sorghum is a relatively recent development, originating in late 1980’s Nigeria. There remains substantial scope to optimise the process by tailoring the equipment and conditions utilised more specifically to the raw material. This was the context to the main objectives of this PhD project: towards an improved sorghum brewing process. Two principal approaches were employed: 1. The reduction of primary energy usage by developing novel modifications to the mashing and wort boiling unit operations and 2. Characterisation of the material properties of a substantial co-product of sorghum brewing, sorghum spent grains (SSG) as a pre-requisite to assessing its suitability for the production of value-added products and/or biofuel. The gross chemical composition of five SSG samples sourced from commercial breweries in Africa were determined, with the sum of individual components accounting for 97.8 % material on a dry weight basis (d.b.; average value). The SSG samples contained relatively high amounts of protein (>38.0 %) as compared to values quoted for brewers’ spent grains. SSG samples were found to contain considerable amounts of residual starch (>4.55 %; d.b.), which suggested that the practice for milling and mashing with unmalted sorghum, in the breweries from which samples were sourced, could be further optimised. By boiling at reduced temperature, required energy input is reduced as the latent heat of evaporation is not provided. In Chapter 3, the impact of reduced temperature boiling on the formation and stripping of key wort volatile compounds was evaluated at both industrial scale and pilot scales (10 hL). As compared to control boiling (3.5 % evaporation), the stripping efficiency of simmer boiling (0 % evaporation) was reduced for some volatiles, including: hexanal, linalool, and β-myrcene. One key lager flavour volatile, dimethyl sulphide (DMS), displayed similar patterns of stripping when comparing simmer and control boils. In Chapter 4, we report the evaluation of a novel wort boiling technology in production-scale trials at a brewery in Ghana. The ‘PDX’ wort boiler utilises direct steam injection into wort and claims improved efficiency of heat transfer and volatile stripping. The present work demonstrated that steam injection technology could provide an approximate 50 % reduction in energy input during the boil, without significant deleterious effects on final product quality. Finished beverages produced using steam injection technology were determined to be within brand specifications by a trained sensory panel. Chapters 5 and 6 report investigations aimed at reducing the energy input when mashing with unmalted sorghum and developing knowledge of how the structure and composition of different sorghum cultivars interacts with the mashing conditions employed. Designed experimentation was used to investigate the impact of mash conditions on a novel low-temperature mashing system and a high-temperature enzyme mashing system. The reduced energy, low-temperature system was comparable to the high-temperature system in terms of extract and FAN yield, when mashing with unmalted Sorghum bicolor cv. Fara Fara. Furthermore, both enzyme systems were able to produce acceptable wort using agricultural sorghum varieties, providing that the starch properties were similar to brewing cultivars in terms of their pasting characteristics and grain hardness. Poor mashing properties were associated with cultivars displaying increased physical interaction of endosperm protein with starch, resulting in reduced starch swelling during mashing.

The removal of yeast biomass (cropping) at the end of fermentation to inoculate a subsequent fermentation (serial-repitching) is common practice in the brewing industry. Between successive fermentations cropped yeast is stored as a slurry in cooled storage vessels under anaerobic conditions until required for subsequent use. Maintenance of yeast quality during storage is critical for subsequent fermentation performance. An assumption is made in brewing that all strains benefit from storage at 3-4°C. To test this assumption a model working system was initially established to assess cooling times of lager yeast in different suspension media. Preliminary investigations focussing on freshly propagated yeast slurry demonstrated that whilst the deleterious effects of extremely high storage temperatures on lager brewing yeast physiology was in line with expectation, utilization of traditionally recommended storage temperatures does not necessarily benefit yeast physiology when compared to slurry maintenance at slightly higher temperatures. Genome-scale transcriptional analysis in slurries cropped following an initial fermentation suggested that lager yeast might experience cold stress during slurry maintenance at typically recommended storage temperatures. In contrast, maintenance of lager yeast at a slightly higher storage temperature, in this case 10°C, yielded no adverse impact on key indicators of brewing yeast physiological state or on subsequent fermentation profiles following repitching into fermentations. Whilst these observations were not made using full production scale, they do indicate that optimal storage may not be currently being deployed for brewing yeast at full scale.

This thesis studies the change process of risk management practices associated with the implementation of Enterprise Risk Management (ERM) and the extent to which it can lead to changes in capital allocation practices. The study develops a theoretical framework to study risk management changes, which draws on structuration theory (Giddens, 1979, 1984) and institutional theory, particularly the institutional framework of Burns and Scapens (2000), as well as new institutional sociology theory. A two-stage empirical study was undertaken in non-life insurance companies. The first stage was a field study of 10 listed non-life insurance companies, while the second stage was a case study of a large non-life insurance company. Multiple data collection methods were used including semi-structured interviews, documentary evidence, annual reports, and publicly available data. Findings show internal, coercive, and normative pressures have mainly driven the ERM adoption decision. The literature supports the impact of coercive, mimetic, and normative pressures on the trend toward ERM in financial industries. However, the study finds that internal pressures related to achieving the company's objectives are either equal to or surpass the external pressures. The study also provides empirical evidence of the changes in risk management practices, which include capital allocation change process associated with ERM implementation. Effective capital allocation requires the incorporation of ERM elements in the whole process of allocating capital. Furthermore, new capital allocation routines and institutions are produced. The study shows that the risk-based capital allocation method is intra- and extra-institutionalised at the company level. The main contribution of this thesis is to identify the nature of ERM adoption and implementation in insurance companies. More specifically, this study provides a better understanding of the institutional forces driving ERM adoption and offers empirical evidence on ERM implementation and the change in risk management practices (routines) within nonlife insurance companies. Moreover, this study avoids the limitations of previous research that was based on surveys, and it does so by conducting an exploratory field study and explanatory case study to address the changes in risk management practices. Practices and process need to be located in their institutional context and hence cannot be reflected in surveys.

The impact of energy drinks and their ingredients on cognitive functioning has been of considerable scientific interest in recent years; however studies investigating cognitive effects of energy drink consumption have centred on the postprandial impact, that is the influence of their ingredients once absorbed into the blood. It is possible however, that sensory perception of these drinks, or their ingredients can influence cognition. The four studies outlined in this thesis aim to examine the influences of sensory perception of energy drinks in human volunteers and compare these with the effects observed in the postprandial period on a range of cognitive tasks. Postprandially energy drink treatments were observed to reduce reaction times and improve accuracy compared with a placebo control in a saccadic peripheral conflict task when a 200ms gap was present between a pre-stimulus cue and the stimulus; however when this gap was absent accuracy decreased, suggesting treatment had affected information processing and decision making processes. Sensory perception of a non-carbonated energy drink was observed to improve reaction time and accuracy in a manual choice reaction time task irrespective of gap presence, however an artificially sweetened placebo energy drink had similar effects, but only when the pre-stimulus gap was present. This thesis demonstrates that energy drinks can influence behavioural performance not only by increasing plasma glucose and caffeine levels in the postprandial period, but also through chemosensory perception, an effect elicited by the reward value of taste and flavour perception which is perhaps related to the calorific content of carbohydrates.

Flavour perception of food and beverages is a complex multisensory experience involving the gustatory, olfactory, trigeminal, auditory and visual senses. Thus, investigations into multimodal flavour perception require a multidisciplinary design of experiments approach. This research has focussed on beer flavour perception and the fundamental interactions between the main flavour components - sweetness, bitterness (from hop acids), alcohol content and carbonation level. A model beer was developed using representative ingredients which could be manipulated to systematically vary the concentration of the main flavour components in beer and was used in the following experiments. Using a full factorial design, the physical effect of ethanol, C02 and hop acid addition was determined by headspace analysis and in-nose expired breath (in-vivo) measurements. Results from headspace and in-vivo methods differed and highlighted the importance of in-vivo measures when correlating to sensory experience. Ethanol and C02 significantly increased volatile partitioning during model beverage consumption. The effects of ethanol and C02 appeared to be independent and therefore additive, which could account for up to 86% increase in volatile partitioning. This would increase volatile delivery to the olfactory bulb and thus potentially enhance aroma and flavour perception. This was investigated using quantitative descriptive analysis. Results showed that C02 significantly impacted all discriminating attributes, either directly or as a result of complex interactions with other design factors. C02 suppressed the sweetness of dextrose and interacted with hop acids to modify bitterness and tingly perception. Ethanol was the main driver of complexity of flavour and enhanced sweet perception. In a first study of its kind, the impact of C02 on gustatory perception was further investigated using functional magnetic resonance imaging (fMRI) to understand cortical response. In addition, classification of subjects into PROP taster status groups and thermal taster status groups was carried out. Groups were tested for their sensitivity to oral stimuli using sensory techniques and for the first time, cortical response to taste and C02 was investigated between groups using fMRI techniques and behavioural data. There was no correlation between PROP taster status and thermal taster status. PROP taster status groups varied in their cortical response to stimuli with PROP super-tasters showing significantly higher cortical activation to samples than PROP non-tasters. The mechanism for thermal taster status is not currently known but thermal tasters were found to have higher cortical activation in response to the samples. The difference in cortical activation between thermal taster groups was supported by behavioural data as thermal tasters least preferred, but were more able to discriminate the high C02 sample than thermal non-tasters. This research has provided in-depth study into the importance of flavour components in beer. It advances the limited data available on the effects of C02 on sensory perception in a carbonated beverage, providing sound data for the successful development of products with reduced ethanol or C02 levels. The use of functional magnetic resonance imaging has revealed for the first time that oral C02 significantly increases activation in the somatosensory cortex. However, C02 seemed to have a limited impact on activation strength in 'taste' areas, such as the anterior insula. Research comparing data from PROP taster status groups and thermal taster status groups has given insight into the possible mechanisms accounting for differences in oral intensity of stimuli.