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Item Slow and steady-small, but insufficient, changes in food and drink availability after four years of implementing a healthy food policy in New Zealand hospitals(BioMed Central Ltd, 2024-12) Mackay S; Rosin M; Kidd B; Gerritsen S; Shen S; Jiang Y; Te Morenga L; Ni Mhurchu CBACKGROUND: A voluntary National Healthy Food and Drink Policy (the Policy) was introduced in public hospitals in New Zealand in 2016. This study assessed the changes in implementation of the Policy and its impact on providing healthier food and drinks for staff and visitors in four district health boards between 1 and 5 years after the initial Policy introduction. METHODS: Repeat, cross-sectional audits were undertaken at the same eight sites in four district health boards between April and August 2017 and again between January and September 2021. In 2017, there were 74 retail settings audited (and 99 in 2021), comprising 27 (34 in 2021) serviced food outlets and 47 (65 in 2021) vending machines. The Policy's traffic light criteria were used to classify 2652 items in 2017 and 3928 items in 2021. The primary outcome was alignment with the Policy guidance on the proportions of red, amber and green foods and drinks (≥ 55% green 'healthy' items and 0% red 'unhealthy' items). RESULTS: The distribution of the classification of items as red, amber and green changed from 2017 to 2021 (p < 0.001) overall and in serviced food outlets (p < 0.001) and vending machines (p < 0.001). In 2021, green items were a higher proportion of available items (20.7%, n = 815) compared to 2017 (14.0%, n = 371), as were amber items (49.8%, n = 1957) compared to 2017 (29.2%, n = 775). Fewer items were classified as red in 2021 (29.4%, n = 1156) than in 2017 (56.8%, n = 1506). Mixed dishes were the most prevalent green items in both years, representing 11.4% (n = 446) of all items in 2021 and 5.5% (n = 145) in 2017. Fewer red packaged snacks (11.6%, n = 457 vs 22.5%, n = 598) and red cold drinks (5.2%, n = 205 vs 12.5%, n = 331) were available in 2021 compared to 2017. However, at either time, no organisation or setting met the criteria for alignment with the Policy (≥ 55% green items, 0% red items). CONCLUSIONS: Introduction of the Policy improved the relative healthiness of food and drinks available, but the proportion of red items remained high. More dedicated support is required to fully implement the Policy.Item A randomized cross-over trial to determine the effect of a protein vs. carbohydrate preload on energy balance in ad libitum settings(BioMed Central Ltd, 2019-11-09) Gibson MJ; Dawson JA; Wijayatunga NN; Ironuma B; Chatindiara I; Ovalle F; Allison DB; Dhurandhar EJBACKGROUND: Although high protein diets have been tested in controlled environments for applications to weight management, it is not understood if adding high protein foods to the diet would impact ad libitum energy balance in the absence of other lifestyle changes. METHODS: This double-blinded randomized crossover trial compared the effects of a protein shake (PS) to a carbohydrate shake (CS), consumed prior to each major meal to equate to 20% of total energy needs over the course of the day, on energy balance over two 5-day treatment periods in healthy adults with BMI 20-30 kg/m2. Tri-axial accelerometers estimated physical activity energy expenditure. Ad libitum energy intake was measured in a laboratory kitchen. RESULTS: Energy balance was positive during both treatment periods but was not different between periods. There were no interactions between treatment and preload caloric dose or treatment and BMI status on energy balance. Satiety ratings did not differ for any pairwise comparisons between treatment and caloric dose. Controlling for gender and basal metabolic rate, thermic effect of food was greater for PS than CS. CONCLUSIONS: Preload periods significantly altered the macronutrient composition of the overall diet. This study found limited evidence that carbohydrate or protein preloads have differential effects on energy balance in short-term ad libitum settings. TRIAL REGISTRATION: This trial was pre-registered on clinicaltrials.gov as NCT02613065 on 11/30/2015.Item Effects of Whey Protein on Skeletal Muscle Microvascular and Mitochondrial Plasticity Following 10-Weeks of Exercise Training in Men with Type-2 Diabetes(Canadian Science Publishing, 2021-08) Gaffney K; Lucero A; Macartney-Coxson D; Clapham J; Whitfield P; Palmer BR; Wakefield S; Faulkner J; Stoner L; Rowlands DSAbstract Skeletal muscle microvascular dysfunction and mitochondrial rarefaction feature in type 2 diabetes mellitus (T2DM) linked to low tissue glucose disposal rate (GDR). Exercise training and milk protein supplementation independently promote microvascular and metabolic plasticity in muscle associated with improved nutrient delivery, but combined effects are unknown. In a randomised-controlled trial, 24 men (55.6 y, SD 5.7) with T2DM ingested whey protein drinks (protein/carbohydrate/fat: 20/10/3 g; WHEY) or placebo (carbohydrate/fat: 30/3 g; CON) before/after 45 mixed-mode intense exercise sessions over 10 weeks, to study effects on insulin-stimulated (hyperinsulinemic clamp) skeletal-muscle microvascular blood flow (mBF) and perfusion (near-infrared spectroscopy), and histological, genetic, and biochemical markers (biopsy) of microvascular and mitochondrial plasticity. WHEY enhanced insulin-stimulated perfusion (WHEY-CON 5.6%; 90% CI −0.1, 11.3), while mBF was not altered (3.5%; −17.5, 24.5); perfusion, but not mBF, associated (regression) with increased GDR. Exercise training increased mitochondrial (range of means: 40%–90%) and lipid density (20%–30%), enzyme activity (20%–70%), capillary:fibre ratio (∼25%), and lowered systolic (∼4%) and diastolic (4%–5%) blood pressure, but without WHEY effects. WHEY dampened PGC1α −2.9% (90% compatibility interval: −5.7, −0.2) and NOS3 −6.4% (−1.4, −0.2) expression, but other messenger RNA (mRNA) were unclear. Skeletal muscle microvascular and mitochondrial exercise adaptations were not accentuated by whey protein ingestion in men with T2DM. ANZCTR Registration Number: ACTRN12614001197628. Novelty: • Chronic whey ingestion in T2DM with exercise altered expression of several mitochondrial and angiogenic mRNA. • Whey added no additional benefit to muscle microvascular or mitochondrial adaptations to exercise. • Insulin-stimulated perfusion increased with whey but was without impact on glucose disposal. Résumé Le dysfonctionnement microvasculaire du muscle squelettique et la raréfaction mitochondriale caractérisant le diabète de type 2 (« T2DM ») sont liés à un faible taux d’élimination du glucose tissulaire (« GDR »). L’entraînement physique et la supplémentation en protéines du lait favorisent indépendamment la plasticité microvasculaire et métabolique dans le muscle; cette plasticité est associée à une amélioration de l’apport de nutriments, mais les effets combinés sont inconnus. Dans un essai contrôlé randomisé, 24 hommes (55,6 ans, SD 5,7) aux prises avec le T2DM consomment des boissons protéinées de lactosérum (protéines / glucides / lipides: 20/10/3 g; « WHEY ») ou un placebo (glucides / lipides: 30/3 g; « CON ») avant / après 45 séances d’exercice intense en mode mixte sur 10 semaines, et ce, pour examiner les effets sur le flux sanguin microvasculaire (« mBF ») et la perfusion (spectroscopie proche infrarouge) stimulés par l’insuline (clamp hyperinsulinémique), des variables histologiques, génétiques et des marqueurs biochimiques (biopsie) de la plasticité microvasculaire et mitochondriale. WHEY améliore la perfusion stimulée par l’insuline (WHEY-CON 5,6 %; IC 90 % −0,1, 11,3), tandis que le mBF n’est pas modifié (3,5 %; −17,5, 24,5); la perfusion, mais pas le mBF, est associée (régression) à une augmentation du GDR. L’entraînement à l’exercice augmente la densité mitochondriale (gamme de moyennes: 40-90 %) et lipidique (20−30 %), l’activité enzymatique (20−70 %), le ratio capillaire: fibre (∼25 %) et diminue les pressions systolique (∼4 %) et diastolique (4−5 %), mais sans effets de WHEY. WHEY amortit l’expression de PGC1α −2,9 % (intervalle de compatibilité de 90 % : −5,7, −0,2) et NOS3 −6,4 % (−1,4, −0,2), mais les autres ARN messager (ARNm) ne sont pas clairs. Les adaptations microvasculaires et mitochondriales des muscles squelettiques causées par l’entraînement physique ne sont pas accentuées par la consommation de protéines de lactosérum chez les hommes aux prises avec le T2DM. Numéro d’enregistrement ANXCTR : ACTRN12614001197628. [Traduit par la Rédaction] Les nouveautés: • La consommation prolongée de lactosérum en présence de T2DM combinée à l’entraînement physique modifie l’expression de plusieurs ARNm mitochondriaux et angiogéniques. • Le lactosérum n’ajoute aucun avantage supplémentaire aux adaptations microvasculaires ou mitochondriales musculaires à l’exercice physique. • La perfusion stimulée par l’insuline augmente avec le lactosérum mais n’a pas d’impact sur l’élimination du glucose.Item Sugar-sweetened beverages consumption among New Zealand children aged 8-12 years: a cross sectional study of sources and associates/correlates of consumption(BioMed Central Ltd, 2021-12-13) Smirk E; Mazahery H; Conlon CA; Beck KL; Gammon C; Mugridge O; von Hurst PRBACKGROUND: The benefit of reducing sugar-sweetened beverage (SSB) consumption is widely accepted, but updated and in-depth data on New Zealand (NZ) children's SSB consumption is lacking. The aims of this study were to describe beverage consumption, focusing on SSBs in primary school age children living in Auckland; to examine the association of selected socio-demographic, home, community and school factors and children's beverage knowledge/attitudes with regards to beverage consumption; to explore the relationship between SSBs consumption and adiposity in children. METHODS: A cross-sectional, Auckland-wide survey of 578 school age children (8-12 years) was conducted using questionnaires to collect data on beverage consumption, beverage knowledge/attitudes, and selected socio-demographic and home, community, school factors. Body fat percentage (BF%) was assessed using bioelectrical impedance (BIA). RESULTS: Ninety-six percent of children consumed ≥1 serving of SSBs a week; with ≥5 servings reported by 62% of children. Of all SSBs assessed, consumption of ≥1 serving of sugar sweetened milk-based beverages (85%, mainly milk drinks made from powder) was most prevalent, followed by fruit juice (46%) and sugar-containing carbonated drinks (39%, mainly soft/fizzy drinks). Among unsweetened beverages, plain water was reported to be consumed < 2 times a day by 22% of children, and plain milk < 1 serving a day by 53%. Higher consumption of SSBs was associated with socio-economic disadvantage, non-NZ European ethnicities (Māori, Pacific, Asian, others), availability of SSBs in the home, frequent takeaway/convenience shop visits, children's incorrect perception of adequate SSBs consumption frequency, and higher BF% (females only). School health policy and encouragement of children to consume un-sweetened beverages was not associated with SSBs consumption. CONCLUSIONS: The consumption of SSBs is prevalent in NZ school age children, with higher consumption rates observed among those from socially disadvantaged areas. This high consumption is associated with higher BF% in females. Multi-contextual interventions to decrease SSBs should target children, and their families/environment, particularly those from socially disadvantaged areas.Item 2021 Assessment of New Zealand district health boards' institutional healthy food and drink policies: the HealthY Policy Evaluation (HYPE) study(Pasifika Medical Association Group (PMAG), 2022-08-19) Gerritsen S; Kidd B; Rosin M; Shen S; Mackay S; Te Morenga L; Mhurchu CNAIM: To assess adoption of the voluntary National Healthy Food and Drink Policy (NHFDP) and the alignment of individual institutional healthy food and drink policies with the NHFDP. METHOD: All 20 district health boards (DHBs) and two national government agencies participated. Policies of those organisations that had not fully adopted the NHFDP were assessed across three domains: nutrition standards; promotion of a healthy food and beverages environment; and policy communication, implementation and evaluation. Three weighted domain scores out of 10, and a total score out of 30 were calculated. RESULTS: Nine of the 22 organisations reported adopting the NHFDP in full. Of the remaining 13, six referred to the NHFDP when developing their institutional policy and three were working toward full adoption of the NHFDP. Mean scores (SD) were 8.7 (1.0), 6.1 (2.6) and 3.8 (2.2) for the three domains, and 18.6 (4.8) in total. Most individual institutional policies were not as comprehensive as the NHFDP. However, some contained stricter/additional clauses that would be useful to incorporate into the NHFDP. CONCLUSION: Since a similar policy analysis in 2018, most DHBs have adopted the NHFDP and/or strengthened their own nutrition policies. Regional inconsistency remains and a uniform mandatory NHFDP should be implemented that incorporates improvements identified in individual institutional policies.Item Studies on the gastric digestion of plant-based alternative milks : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Manawatū, New Zealand(Massey University, 2022) Wang, XinPlant-based alternative milks are colloidal dispersions consisting of extracted plant protein, oil bodies and other biopolymers that resemble cow milk in appearance. In recent years, plant-based alternative milks have become increasingly popular because of their sustainability and perceived health benefits. However, little is known about the structural changes and colloidal stability of these milks during gastric digestion and how these changes impact the delivery and absorption of nutrients. The aim of this PhD project was to understand the digestion behaviour of plant-based alternative milk in the gastric environment, with a focus on the changes in microstructure, colloidal stability, physiochemical properties and protein hydrolysis and their direct consequences on the kinetics of nutrient release and delivery. The impact of cow milk protein on the digestion behaviour of oat-based milk was also explored. State-of-the-art dynamic in vitro and in vivo gastric digestion models were employed for this project. The results demonstrated that plant-based alternative milks made with different plant materials (almonds, soybeans and oats) behaved differently under gastric conditions, in particular, in terms of changes in microstructures, colloidal stability and protein digestibility. Almond milk oil bodies flocculated, coalesced and then quickly layered into an upper lipid-rich layer and a lower aqueous phase upon gastric digestion. Soymilk coagulated and formed small-sized particles which sedimented rapidly. In contrast, no significant changes in the structure and colloidal stability were observed in oat milk. These variations in colloidal stability resulted in different gastric release profiles of protein and lipid. These results highlight the role of intragastric structural properties as a determining factor in controlling the kinetics of delivery of macronutrients. This study also clearly showed the influence of cow milk protein on the structural and colloidal stability of the oat milk-cow milk blend during gastric digestion. The findings from this thesis provide new knowledge and understanding of the gastric digestion of plant-based alternative milks and how their behaviours are different from cow milk. The knowledge gained from this PhD project may provide valuable information into the tailored design of novel plant-based alternative milk products or milk blended products for specific consumers' needs.Item Evaluating temporal multiple sip approaches to characterise product experience : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Palmerston North Campus, New Zealand(Massey University, 2021) Weerawarna N. R. P., MaheekaAs consumers become ever more demanding, methods that capture detailed insights into consumer product experiences are much needed. Adapting temporal sensory and affective measures to cater this demand beyond single time points and small sample sizes is one such approach, and of a recent interest in the sensory and consumer science research area. Firstly, this research compared single and multiple sip sensory approaches using static and time-dependent sensory methodologies with an expert panel. Multiple sip evaluations were designed to represent the consumption of a whole product serving, in this case vanilla milkshakes. Generalised linear models with Analysis of Deviance were employed as a novel approach to analyse naturally correlated temporal data. Additionally, the impact of milkshake sipping method and panel type on multiple sip temporal profiles of the milkshakes was investigated. In addition, temporal methods were adapted to investigate consumer affective responses, both hedonic and emotional response, over multiple sips. Temporal drivers of product acceptance and rejection were identified in analyses combining sensory and affective data. Finally, the impact of individual differences in sweet liker and PROP (6-n-propylthiouracil) taste phenotypes across multiple sip temporal emotion profiles of the milkshakes was investigated. Multiple sip evaluation of both static and temporal methods (Temporal check all that apply (TCATA) and Temporal dominance of sensation (TDS)) provided further discrimination of products than on a single sip of milkshakes. The use of static and temporal methods as complementary approaches, rather than as alternatives, was valuable in obtaining holistic temporal profiles of products. Specifically, the use of generalised linear models and Analysis of Deviance allowed to investigate the dynamics of within-sip and between sip which was a novel addition to the knowledge of temporal data analysis. However, temporal sensory product profiles varied depending by sipping method and emphasised the importance of adapting product evaluation protocols based on intended consumption methods of the beverages. Moreover, temporal sensory profiles were affected by panel type, i.e. experts or consumers, and the insights obtained from the two panel types were not interchangeable. Using expert panels, even on multiple sip evaluations did not provide closer insights into actual consumer product experience. The research highlighted that choice of panel type needs to be aligned with any respective project objectives. Temporal sensory responses of consumers were associated with temporal liking and emotions over multiple sips. Furthermore, dominant emotions reported depended on sweet liker status and PROP taster status. The research findings highlighted the importance of investigating temporal affective responses, i.e. both liking and emotions, and individual differences alongside temporal sensory responses in consumer research to obtain closer insight into actual product experience. Generally, findings were attribute and product specific and hence wider research using additional products and different food matrices are required to validate the findings. Overall, the research outcomes emphasised the importance of multiple sip sensory evaluations to represent the consumption of whole product servings, using appropriate sipping methods, and panels. Investigating the affective responses and individual differences were important to capture different insights according to respective project objectives.Item Beverage consumption in Auckland primary school children : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics at Massey University, Albany, New Zealand(Massey University, 2019) Smirk, EmmaBackground: The New Zealand (NZ) Ministry of Health advises that plain water and plain low-fat milk should be consumed daily and that if children are to drink sugar-sweetened beverages (SSB) they should be limited. The latest comprehensive NZ beverage intake data in 8 to 12 year old children was published in 2008, however, fizzy drink intake data is updated annually. This means that NZ is lacking a full picture of children’s beverage consumption. SSB intake has been associated with weight gain in some studies. However, most of these studies calculate adiposity using body mass index (BMI) and few measure body fat percentage (BF%). International and limited national evidence has identified home availability, parental encouragement, socioeconomic status, and knowledge in children as factors associated with SSB intake. Many NZ schools have become ‘water-only’ schools (WOS) to try to reduce SSB consumption. Aim: To investigate beverage consumption in 8 to 12 year old Auckland primary school children. Methods: This cross-sectional study evaluated beverage intake and associated factors using self-administered questionnaires. SSB consumption measurements consisted of 17 types of beverages, and different combinations of these. Body composition was measured using bioelectrical impedance analysis (BIA). Chi squared and Mann-Whitney tests were used to examine the associations between SSB consumption and the factors associated with it. Results: Children (n=695, 9.9±0.7 years, 44.8% male) were recruited from 6 schools (4 WOS). Plain water and plain milk were consumed less than once per day by 11.6% and 54.7% of the children, respectively. Soft drink and fruit juice were consumed more than once per week by 30.6% and 39% of the children, respectively. SSBs (p<0.001), including fruit juice (p=0.021), had a positive relationship with BF% in girls. There was an increased likelihood of consuming beverages at least once per week if they were usually available at home. Receiving a lot of encouragement for healthy beverage intake from parents or school had an inverse relationship with SBB intake (p<0.001). Low socioeconomic status was inversely associated with SSB intake (p<0.001). WOS had a higher consumption of SSBs compared to non-WOS (p<0.001). Conclusions: Too many children in this cohort were not meeting the NZ Ministry of Health recommendations for plain water and milk consumption. Thus, they may benefit from increasing their intake, whilst decreasing their SSB intake. If parents limited SSB home availability and encouraged intake of healthy beverages it may contribute to a decrease in their children’s SSB consumption. Our findings support a recommendation to include fruit juice in any public health actions to discourage SSB consumption. More research is needed to assess school water-only policies and their effect on SSB consumption.Item Development and characteristics of green tea kombucha : a thesis presented in partial fulfilment of the requirements for the degree of Master of Food Technology at Massey University, Albany, New Zealand(Massey University, 2018) Wang, XiaoleiFermentation by microorganisms plays an important role in the development of manufactured food due to its ability to extend the shelf-life of the products as well as improving the nutritional value and sensory properties. Demand and interest in the consumption of fermented products, such as yoghurt, cheese, buttermilk and meat has continued to increase in the past few decades, due to their beneficial health effects which include prevention of chronic disease and enhancement of the immune system. However, because of the health challenges of these products such as lactose intolerance, high cholesterol and fat content, as well as protein allergies, consumer interest in the consumption of non-dairy and plant-based fermented products such as water kefir and kombucha is growing. Kombucha is a traditional refreshing home-made beverage with a slightly acidic, sweet and alcoholic taste, which is thought to have originated in Germany, China and Russia, but is now consumed worldwide. Kombucha is usually produced by the fermentation of tea and sugar with a symbiotic consortium of acetic acid bacteria and yeasts, commonly known as the kombucha starter culture. The physico-chemical characteristics, microbial profiles and sensory properties of kombucha are significantly affected by fermentation conditions including sugar concentration, fermentation time and temperature. The majority of previous studies have focused on the comparison of different substrates for kombucha preparation and their effects on the final composition of kombucha. Therefore, there is scanty information in the development and characteristics of kombucha under different production conditions. The present study investigated the effects of sugar concentration, fermentation time and temperature on the fermentation of green tea kombucha aimed at optimising the process to develop a consistent high quality beverage. The development and characteristics of green tea kombucha were investigated in four- integrated experimental phases. Phase 1 enumerated the microflora in the kombucha starter culture (acetic acid bacteria, lactic acid bacteria and yeasts). The effect of fermentation time (7, 10 and 14 days) on the development of kombucha was studied in Phase 2 in order to select the optimum fermentation time. In Phase 3, the effects of two sugar concentrations (7% and 10%) and two fermentation temperatures (22℃, 24℃) on the physico-chemical, microbial and sensory characteristics of green tea kombucha were studied, with the aim of selecting the optimum sugar concentration and fermentation temperature for the development of green tea kombucha. The antibacterial activity of the final optimised green tea kombucha were investigated and the stability of the beverage was monitored during storage (4℃) for 4 weeks in Phase 4. Various analyses of green tea kombucha samples were conducted during fermentation and storage in order to investigate the physico-chemical, microbial and sensory characteristics of the beverage: sugars, organic acids, ethanol, antioxidant, titratable acidity (TA) and viable cell counts (VCC) of kombucha microorganisms were analysed, pH, total soluble solids (TTS) and colour were also measured. Acetic acid bacteria (6.08±0.06 log cfu/ml) and yeasts (7.13±0.07 log cfu/ml) were present in the kombucha starter culture used in this study, while no lactic acid bacteria were found. Results from Phase 2 showed that fermentation time contributed to the physico-chemical, microbial and sensory properties of green tea kombucha. In Phase 2, TA increased steadily from Day 7 (0.36±0.02 - 0.42±0.04) to Day 14 (0.88±0.04 - 1.01±0.06) (p<0.05), while pH, total soluble solids, VCC and overall consumer acceptability decreased (p<0.05). In Phase 3, kombucha samples containing 7% or 10% sugar and fermented at 24℃ for 7 days were characterised by higher levels (p<0.05) of organic acids with lower pH, TSS and VCC than kombucha fermented at 22℃. No significant differences (p<0.05) in colour, VCC and levels fermentation. Based on the physico-chemical, microbial and sensory characteristics of green tea kombucha beverage in Phases 2 and 3, the optimum fermentation conditions were kombucha containing 7% sugar and fermented at 22℃ for 7 days. The results of the disc diffusion studies showed that the final optimised green tea kombucha had antibacterial activities against Escherichia coli 111, Listeria monocytogenes 15E03-1, Salmonella typhimurium ESR3479, Staphylococcus aureus MU-A57 and Pseudomonas aeruginosa MU-A26. High quantities of antioxidants (gallic acid = 5.7±0.04 µg/ml, EGC = 130.89±6.86 µg/ml, EGCG = 152.26±39.70 µg/ml and ECG = 41.11±16.23 µg/ml) were also present in this beverage. These observations suggested that consumption of green tea kombucha may exert beneficial health effects. During storage (4℃) for 4 weeks, the colour of the optimised green tea kombucha was stable and the consumer acceptability of green tea kombucha beverage remained high. Green tea kombucha containing 7% sugar and fermented at 22℃ for 7 days was well-liked by consumer panellists (n=60) and this beverage contained 0.35±0.03% (w/v) gluconic acid, 0.31±0.00% (w/v) acetic acid and high levels of certain antioxidants which may confer beneficial effects on human health.Item Process development for a sheep whey beverage : a thesis presented in partial fulfilment of the requirements for the degree of Master of Food Technology at Massey University, Palmerston North, New Zealand(Massey University, 2017) Weerawarna N R P, Maheeka IsurinieThe potential of New Zealand sheep whey as a stable base ingredient in beverage manufacturing was studied using 4 model whey and 7 commercial whey streams. In order for sheep whey containing beverages to have a commercially adequate shelf life they are required to undergo a heat treatment. Due to the artisan small scale nature of sheep cheese manufacture in New Zealand heat treatment using continuous processing was not deemed feasible. The most likely form of heat treatment would be in package batch heating to 90°C with the pH of the beverage less than pH 4.6. Thus this study investigated the variations in the physicochemical composition of sheep whey as a function of cheese manufacturing on heat treatment (90°C/ 5min) under varying acidic pH conditions (pH 4.5 and pH 3.5). The composition of sheep whey varied primarily based on the pH of the cheese curd formation and separation method. Additionally, the whey composition also differed with the type of cheese produced and quality control of the process by each manufacturer. Of particular importance is the curd separation technique as this can result in casein contamination of the whey. A model study containing 5% w/v of contaminating curd in whey showed that significant Ca and Mg migrated from the curd into the whey during overnight cold storage (5°C) at pH 3.5 resulting in an overall increase in ionic strength of the whey. The stability of sheep whey during heat treatment (90°C for 5 min) at pH 4.5 and pH 3.5 was studied via sedimentation and colour (L, a, b) measurement. The L value of whey samples heated at pH 4.5 increased and the samples produced 13 – 40% (v/v) sedimentation after overnight storage at 5°C. Comparatively, whey heated at pH 3.5 was generally stable with less than 1% (v/v) sedimentation and no significant changes in the L value. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed comparatively high loss of monomeric whey proteins in whey heated at pH 4.5 than at pH 3.5 and further confirmed the above results. However, a commercial whey with high ionic strength (conductivity 193.6 mS cm-1) was unstable at pH 3.5 heat treatment and produced about 40% (v/v) sedimentation and a prominent increase in the L value. Consequently, an extended study on the effect of ionic strength, varied by the addition of NaCl, on heat stability (90°C for 5 min at pH 3.5) of sheep whey was performed. Whey was stable with up to 0.1 mol L-1 added NaCl (conductivity 102.1 mS cm-1) and produced 6% (v/v) sedimentation after the heat treatment followed by the overnight storage. In contrast, a dramatic increase in sedimentation (about 60%, v/v) was evident at 0.15 mol L-1 NaCl with gradual reduction of sedimentation upon subsequent addition of NaCl. Transmission electron microscopy (TEM) images of the sediments showed hairy like aggregates at 0.15 mol L-1 NaCl which became dense with further increases in NaCl concentration and perhaps explain the sedimentation behaviour. Further, conductivity of whey increased linearly with increasing NaCl concentration (R2 = 0.98 at a 95% level of confidence) and thus conductivity measurement could be used to predict the stability of whey during thermal processing. Moreover, a prototype whey beverage was produced using the above established conditions (90°C for 5 min heat treatment at pH 3.5 and conductivity below 102.1 mS cm-1). However, the product, which was heated in 450 mL bottles (at 1.94°C/ min) rather than the test tubes (at 28°C/ min) of the earlier work, were found to be unstable. Further a rapid heat treatment (at 4.7°C/ min) of the beverage only produced floating aggregates. It was thought that the instability was due to extended heating and cooling rates. A subsequent study showed that holding time at the heat treatment affected the properties of whey protein aggregates and consequently produced either floating aggregates or sediments. Therefore, minimizing heating and cooling rates would be a significant consideration in commercial scale sheep whey processing. Additionally, the research outcomes would assist on-site decision making for individual cheese manufacturers on the utilisation of different sheep whey streams as a stable base ingredient in beverage processing.