Food and Nutritional Sciences - Masters by Research Theses

Permanent URI for this collection

https://hdl.handle.net/10468/9965

Browse

Now showing 1 - 5 of 13

A study of the milking performance of eight milking machines
(University College Cork, 1968) Cowhig, Michael Joseph; Raftery, Tom
There are twenty makes of milking machines available to the Irish farmer at present. Most of these are available in bucket and pipeline plants but two are available in pipeline plants only. However, 90% of the 30,000 milking machines in the Republic of Ireland are bucket type. All the machines available are the two-chamber type and normally work at a vacuum of 13" to 15" Hg. No two machines have exactly the same properties in pulsation characteristic or design of cluster assembly.
Characterisation of the changes in the physicochemical properties of high-solids skim milk during thermal processing, and their relationship with fouling
(University College Cork, 2023) Murphy, Tara R.; O'Mahony, Seamus Anthony; O’Callaghan, Tom F.; Enterprise Ireland
Fouling of thermal processing equipment during production of dairy products and ingredients is a challenge for the dairy industry, with evaporator fouling during the production of skim milk powder being an area of particular focus. The build-up of foulant mass deposit within different regions of the evaporator technology has significant economic, operational, and environmental consequences for the dairy industry, as the decline in the heat performance of the equipment results in more frequent cleaning required and increased energy and water consumption, in addition to potential deterioration in product quality as the required product temperature may not be achieved. The objectives of the work reported in this thesis were to study the effect of pH on the heat stability and physicochemical properties of concentrated skim milk during thermal processing to assess their contributions to evaporator fouling. Heating concentrated skim milk (30%, w/w, total solids; pH 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7) using a high temperature short time thermal treatment (90 °C x 3 min), using a rheometer, showed that as the pH of the samples decreased, both viscosity and particle size distribution increased after heating, coinciding with an increase in sedimentation. Heat treatment (90 °C x 2 h) of concentrated skim milk at pH 6.2 on the fouling rig resulted in severe fouling. Moreover, when the concentrated skim milk was analysed for particle size and sedimentation after heat treatment using the fouling rig, the findings aligned with the initial analysis conducted during the rheometer based HTST thermal treatment. Further characterisation of evaporator fouling was carried out by heat treating concentrated skim milk samples at pH 6.1, 6.3, 6.5 and 6.7 on the fouling rig while in-line measurements of pH, conductivity and temperature were conducted, followed by analysis of the concentrated skim milk samples, cleaning-in-place chemicals and foulant material adhered to the heat exchanger after the fouling experiments. It was observed that samples of concentrated skim milk that caused fouling also displayed increased viscosity, particle size and sedimentation when compared to the samples that resulted in no fouling. The adhered foulant formed at pH 6.1 and 6.3 was found to consist predominantly of protein on a total solids basis, with protein profiling showing that the most prominent proteins were denatured β-lactoglobulin and α-lactalbumin, as well as a strong presence of caseins. It was found that by maintaining the pH of concentrated skim milk above 6.3, fouling during heat treatment could be successfully avoided. Furthermore, through pH adjustment to achieve no fouling to extensive fouling, it was possible to analyse physicochemical properties such as viscosity, particle size, and sedimentation, to provide a practical approach to predict the potential for fouling in concentrated skim milk. These findings contribute significantly to our understanding of the impact of protein stability on the formation of fouling deposits caused by concentrated skim milk, allow us to develop/validate predictive tools and to develop/test mitigation strategies for fouling.
Nutrient intakes, compliance with recommendations and key sources in women of child-bearing age (18-50y) in Ireland
(University College Cork, 2022-02-09) O'Mahony, Abigail; Walton, Janette; Kehoe, Laura; Flynn, Albert; Cashman, Kevin; Coffey, Aidan
Background: Women’s pre-conceptional health (including nutritional status) is important for both the health of the individual themselves and also for the lifelong health of any occurring offspring. However, it has been estimated that up to 50% of pregnancies are unplanned, thus optimal nutritional status is important for all women of child-bearing age (WCBA) not just those with pregnancy intentions. Despite the accumulation of evidence of the importance of nutritional status at this life-stage, nutrient recommendations for WCBA for the most part don’t differ from recommendations for other population groups. The notable exception to this is that all WCBA are recommended to take a folic acid supplement to reduce the risk of neural tube defects (NTDs) in an occurring pregnancy. Objectives: The overall aim of this thesis was to estimate the nutrient intakes among WCBA in Ireland. The first aim was to estimate the mean daily intake of energy, macronutrients, dietary fibre and salt, to determine compliance with dietary guidelines and to identify the key dietary sources of these nutrients in WCBA. A further aim was to estimate the mean daily intake of micronutrients, the prevalence of inadequate intakes and risk of excessive intakes and to identify the key dietary sources of micronutrient intakes in this population group. Methods: The analysis for this research was based on data from the subset of WCBA (18-50 years) (n 487) in the Irish National Adult Nutrition Survey (NANS) (2008-2010). Food and beverage intakes were estimated using a 4-day semi-weighed food record. Nutrient intakes were estimated using WISP® which uses data from ‘McCance and Widdowson’s the Composition of Foods’, Sixth Edition (plus all nine supplemental volumes). During the NANS, modifications were made to the food composition database to include recipes of composite dishes, fortified foods, nutritional supplements, generic Irish foods that were commonly consumed and new foods on the market. The mean daily intake (MDI) of energy and nutrients were estimated by summing the total amount of energy and each nutrient consumed and dividing the total by the number of recording days (four) using SPSS® Version 26. Compliance with dietary guidelines was examined for macronutrients, dietary fibre and salt. The prevalence of inadequate micronutrient intakes (% upper levels (UL)) was also determined. The percent contribution of specific food groups to mean daily intakes of energy, macro- and micro-nutrients was calculated by the mean proportion method. Results: This study found that that while protein intakes are sufficient among WCBA in Ireland, a large proportion of this population have total fat intakes above recommendations (42%) and carbohydrate intakes below recommendations (59%). This population group also have high intakes of saturated fat (13% of total energy (%TE)), free sugar (9%TE) and salt (5.5g/d from food sources only) and low intakes of dietary fibre (17g/d). Important sources of energy in the diet were ‘cereal & cereal products’ (including potatoes) ‘meat, fish & eggs’ and ‘dairy & dairy products’ which when combined contributed over two-thirds of energy intake on average. However ‘top-shelf’ foods (i.e. ‘sugars, confectionery, preserves & savoury snacks’, ‘biscuits, cakes & pastries’ and ‘sugar-sweetened beverages’) also contributed a high proportion of energy intake (21%) in addition to contributing significantly to intakes of fat (15%), saturated fat (16%) and free sugars (59%). This population group also have high intakes of saturated fat (13% of total energy (%TE)), free sugar (9%TE) and salt (5.5g/d from food sources only) and low intakes of dietary fibre (17g/d). With regard to micronutrients, significant proportions of WCBA have inadequate intakes of vitamin D (93%), vitamin C (48%), calcium (41%), folate (32%), iodine (26%), riboflavin (25%), vitamin A (18%), magnesium (18%) and iron (10%). There was little risk of excessive intakes of micronutrients among WCBA with negligible proportions (<3%) of this population having intakes of vitamin B6 and iron greater than the UL. Important sources of vitamins and minerals were milk and milk products, meats, breads and cereals, especially fortified breakfast cereals, and fruits and vegetables. Conclusions: In summary, this study has found unfavourable intakes of total and saturated fat, carbohydrate, sugar, salt and dietary fibre together with low intakes of key micronutrients in WCBA in Ireland. The data presented in this study will have important implications for public health guidance for this vulnerable population group. Furthermore, information about the relative contributions of specific foods to nutrient intakes will be useful to both policy makers and the food industry to develop targeted dietary strategies to improve the diets of WCBA in Ireland.
Development of patient resources for oncology patients with dysphagia and disease-related malnutrition
(University College Cork, 2021-12-21) Hanna, Michelle; Ryan, Aoife; Power, Derek; Breakthrough Cancer Research; Oesophageal Cancer Fund
Cancer is a leading cause of both morbidity and mortality globally [1]. Additionally, its incidence is continuing to rise year on year. Thus the development of treatments and supports to tackle and reduce cancer morbidity and mortality is of crucial importance. Current research highlights that the loss of body weight, and significantly lean body mass, contributes to increased risk of mortality in those with cancer [2, 3]. Cancer itself and its treatments can cause a variety of debilitating side-effects. These can in turn affect a person’s appetite and their ability to chew and swallow normally. Those suffering from cancers of the head and neck and upper gastrointestinal tract are particularly susceptible to dysphagia (difficulty swallowing), often related to the location of the tumour and its treatment [4]. These negative effects on appetite and normal eating lead to reduced food intake and quality of life, significant weight loss and malnutrition. A supportive, multifaceted, evidence-based approach from an early stage is required to attenuate the development of malnutrition and thus minimise its detrimental impact on treatment outcomes and quality of life. Involuntary weight loss affects between 50-80% of those with cancer and is associated with reduced quality of life, psychological implications, increased treatment-related complications and poorer survival [5]. Currently, no known cure exists for cancer-induced weight loss. The European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines for cancer patients recommend nutrition counselling as the first line of nutrition therapy, and state that the best way to increase energy and protein intake is with normal food: a food-first approach [6]. Prior to the publication of ‘Good Nutrition for Cancer Recovery’ by University College Cork in 2014 no evidence-based resource existed that provided patients with understandable and reliable nutritional information and nourishing recipes to help attenuate cancer-induced weight loss through a food-first approach. A 130-page, evidence-based resource containing 52 high protein, high calorie recipes was created but has been out of print since 2018. To address this, as part of this thesis, a second expanded edition was created: a 250+ page resource containing information, advice, and a bank of 116 nourishing recipes. This is described in chapter 2. All recipes are fortified with high-protein, high-calorie additions and portion sizes were adjusted to ensure meals were small in volume for those with a reduced appetite. The revision of the original recipes also allowed for an enhanced protein to fat ratio and all recipes comply with the energy and protein goals set by the British Dietetic Association (BDA) for nutritionally vulnerable patients [7]. Patients with solid tumours of their upper gastrointestinal tract are especially vulnerable to cancer-induced weight loss, exacerbated by dysphagia [4]. Difficulty chewing and swallowing reduce dietary intake and puts this population at an increased risk of malnutrition. In 2016, a novel written resource, ‘Eating Well with Swallowing Difficulties in Cancer’ was developed by University College Cork, aiming to help attenuate malnutrition and sarcopenia in cancer patients experiencing dysphagia. It consisted of 59 nourishing, texture-modified recipes and evidence-based nutrition advice and information based on the ‘Irish Consistency Descriptors for Modified Fluids and Food (2009)’ [APPENDIX 4]. Ireland’s changeover in 2019 to the International Dysphagia Diet Standardisation Initiative (IDDSI) led to changes in framework structure, terminology used and testing methods, thus all dysphagia resources required updating for compliance. IDDSI is a global initiative providing universal terminology describing food texture and fluid thickness, as used in dysphagia diets [8]. Chapter 3 of this thesis discusses the development of the written resources aimed to help optimise oral intake and attenuate weight loss in head and neck and upper gastrointestinal cancer patients experiencing dysphagia, according to the IDDSI framework. It outlines the creation of appealing recipes that are nourishing and texture-modified for IDDSI levels 3 and 4. These resources aim to help those with cancer in achieving nutrition requirements with all recipes developed to comply fully with the appropriate IDDSI level. It is hoped that these cookbooks with help both patients and their families cope with the challenges of a texture- modified diet and that they will become a useful resource for dietitians and other health care professionals in providing advice on IDDSI meals. Recipes were fortified with high protein, high calorie additions; portion sizes were adjusted to low-volume for easier eating, and texture was altered to meet modified texture guidelines. Thousands of copies of these resource will be printed and distributed to oncology centres nationwide in order to disseminate this knowledge, free of charge, to cancer patients. Chapter 4 of this thesis describes the development of an evidence-based cancer information and support website. With so much unfiltered information available, there is often a lot of confusion around what to believe in relation to diet and cancer. This can leave people extremely vulnerable to misleading information at what is already a very difficult time in their lives. To address this, a one-stop-shop evidence-based website was created. The aim of this website was to dispel the most common myths and misinformation on diet and cancer and provide simplified evidence-based information for people throughout their cancer journey. The main sections covered included problems which may affect eating, cancer prevention, cancer survivors, dysphagia and cancer myths and misconceptions. The overall conclusions are summarised in Chapter 5. Malnutrition is a condition with a multifactorial aetiology and thus must be treated with an effective multimodal approach. However, this is outside the scope of this thesis which deals with its nutritional aspect. Dietary intake may be optimised by providing patients with a resource of high-calorie high-protein, nourishing recipes to improve oral intake and, potentially, attenuate loss of weight and muscle mass – such as the cookbook ‘Good Nutrition for Cancer Recovery’. For those with cancer experiencing swallowing difficulties in addition to malnutrition, separate resources with specific tailored advice, based on IDDSI guidelines, were published. Prior to these booklets being published, no resource existed to tackle the challenging task of creating high protein high calorie recipes which were also texture-modified according to the IDDSI guidelines. To support both projects and patients throughout their cancer journeys, a comprehensive website with easily accessible evidence-based information was created.
Temporal sensory liking methods: an investigation with beef steaks from different production systems
(University College Cork, 2022) Corcoran, Linda; O'Sullivan, Maurice; Crofton, Emily; Teagasc
Research on the impact of the diet of the animal on consumer liking of beef has yielded conflicting results. The aim of this study was to apply the traditional liking method and two temporal liking (TL) methods (free and structured) to determine consumer liking of beef derived from animals that were fed grain (GF), grass silage and grain (SG) or grazed grass (GG) during finishing and use different methods to determine the data quality and consumers variability. Three separate panels of regular beef-eating consumers (n=51; n=52; n=50) were recruited from students and staff at Teagasc Food Research Centre, Dublin, Ireland, to assess the liking of striploin steaks from animals fed either GF, SG, or GG, respectively. Results of chapter 2 revealed significant differences (p≤0.05) in liking between diets in terms of overall liking, juiciness, and tenderness using the free TL method. These effects were not observed using the structured TL or traditional liking methods. Further statistical analysis of the TL methods found that the free TL method yielded more discriminative data than the structured TL method, with significant differences (p≤0.05) found for both overall liking and juiciness. Consumers also found the free TL method easier to perform compared to the structured TL method. The evolution of scores over time (changes in consumer scores over the scoring period) was significant (p≤0.05) for all attributes using the free TL method. These results show that free TL may give rise to new opportunities to elicit more in-depth insight from consumer studies using meat. In addition to answering the research question, TL data also has the potential to give new insight into consumer behaviour in terms of how people approach temporal 8 sensory liking methods. Chapter 3 utilises this consumer behaviour approach to look at three temporal liking studies applying both structured and free TL in terms of data quality, presence or absence of temporality, and correlations between consumer response and self-reported difficulty. Interestingly, the assessment of temporality found that consumers who showed the ability to provide temporal data did not provide it for all attributes studied. The analyses have also demonstrated areas where fatigue and the natural variability in consumer responses may impact data quality. Chapter 4 further analyses data from study 2 from chapters 2 and 3 as this had no missing data. Studies 1 and 3 had missing data due to consumers not providing responses to all time points and attributes during sensory testing. Two TL methods (free and structured) and a traditional liking method were employed to generate data from consumers on their liking of beef steaks derived from a grain supplementation diet for four attributes (overall liking, flavour, tenderness, juiciness). Consumers spent the most time and gave the most responses to the attribute flavour. High levels of variability were found within each liking method. High correlations were also found between attributes within each liking method. For the structured TL, overall liking was found to be significant over time. In addition, the free TL and traditional liking were found to be significantly different from each other (p≤0.05) for liking and flavour attributes and the structured TL and traditional liking were found to be significantly different from each other for flavour. However, the two temporal liking methods did not differ from each other. Two clusters of consumers were found for each attribute, one who slightly liked the attribute and one who slightly disliked the attribute. Some consumers changed cluster groups between attributes. This study has shown that the choice of TL method may make a difference on the data elicited.

Browse

Recent Submissions