Journal Articles

Permanent URI for this collectionhttps://mro.massey.ac.nz/handle/10179/7915

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    Lipidomics of Brain Tissues in Rats Fed Human Milk from Chinese Mothers or Commercial Infant Formula
    (MDPI (Basel, Switzerland), 2019-10-28) Su M; Subbaraj AK; Fraser K; Qi X; Jia H; Chen W; Gomes Reis M; Agnew M; Day L; Roy NC; Young W
    Holistic benefits of human milk to infants, particularly brain development and cognitive behavior, have stipulated that infant formula be tailored in composition like human milk. However, the composition of human milk, especially lipids, and their effects on brain development is complex and not fully elucidated. We evaluated brain lipidome profiles in weanling rats fed human milk or infant formula using non-targeted UHPLC-MS techniques. We also compared the lipid composition of human milk and infant formula using conventional GC-FID and HPLC-ELSD techniques. The sphingomyelin class of lipids was significantly higher in brains of rats fed human milk. Lipid species mainly comprising saturated or mono-unsaturated C18 fatty acids contributed significantly higher percentages to their respective classes in human milk compared to infant formula fed samples. In contrast, PUFAs contributed significantly higher percentages in brains of formula fed samples. Differences between human milk and formula lipids included minor fatty acids such as C8:0 and C12:0, which were higher in formula, and C16:1 and C18:1 n11, which were higher in human milk. Formula also contained higher levels of low- to medium-carbon triacylglycerols, whereas human milk had higher levels of high-carbon triacylglycerols. All phospholipid classes, and ceramides, were higher in formula. We show that brain lipid composition differs in weanling rats fed human milk or infant formula, but dietary lipid compositions do not necessarily manifest in the brain lipidome.
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    Seasonal Variations in the Composition and Physicochemical Characteristics of Sheep and Goat Milks
    (MDPI (Basel, Switzerland), 2022-06-14) Li S; Delger M; Dave A; Singh H; Ye A; Visioli F
    There has been growing consumer interest in sheep and goat milk products as alternatives to cow milk products. The physicochemical characteristics of milk vary not only between ruminant species, but also during different seasons; they determine the nutritional quality and processing properties of the milk. In this study, we characterized sheep and goat milks from New Zealand over the seasons for their composition (macronutrients, macro- and micro-minerals, fatty acids, and proteins) and physicochemical properties (e.g., ionic calcium, fat globule size, casein micelle size, viscosity, and melting behavior of milk fat). Heat-induced (95 °C for 5 min) protein interactions and changes in the physical properties of the milks were also investigated. The compositional and structural features of sheep and goat milks were identified and compared with those reported for cow milk. Seasonal variations in the milk characteristics were more pronounced for sheep milk than goat milk and were probably affected by the production systems. Sheep milk, particularly in the late season, had the largest heat-induced increases in casein micelle size and viscosity, probably arising from the greater casein-whey protein and casein-casein interactions during heat treatment. This study provides comprehensive information on the properties of sheep and goat milks and highlights the interaction effects between species, season, and processing.
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    Integrating Usability Testing with Digital Rhetoric in OWI
    (Elsevier B.V.) Bjork, C
    While usability testing can help instructors improve the design of online writing instruction (OWI), its emphasis on student-users sometimes overlooks the networked rhetorical ecologies in which those student-users operate, tilting online composition pedagogy toward neoliberal models of higher education that cater to the student-as-consumer. In response, I propose augmenting usability testing in online writing education with the theories of digital rhetoric. In the context of OWI, usability theory and digital rhetoric share a similar emphasis on the student as a user or audience, but they also have at least two key differences. First, unlike digital rhetoric, usability testing typically elides the political and ideological implications of student-users’ experiences. Second, the usability theories of Jakob Nielsen, for example, tend to view online interfaces as static objects manipulated by users. Digital rhetoric, on the other hand, sees interfaces as dynamic, real-time interactions. Although both paradigms have their advantages, I argue that integrating usability testing with the theories of digital rhetoric can add complexity to researchers’ understanding of OWI by revealing not only how students use online writing environments but also how they use them rhetorically.
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    Characteristics of Red Deer (Cervus elaphus) Milk: Lactational Changes in Composition and Processing Impacts on Structural and Gelation Properties
    (MDPI (Basel, Switzerland), 2023-04-03) Li S; Saharawat A; Ye A; Dave A; Singh H; Zhou P; Miao S
    In an increasingly diversified global market, milk of minor dairy species has gained interest as a novel and premium source of nutrition. Relative to the major dairy species, much is lacking in our understanding of red deer (Cervus elaphus) milk. In this study, we characterized the compositions (macronutrients, minerals, fatty acids, and proteins) of red deer milk and their variations throughout lactation. We also investigated the structures, physical properties, and gelation (acid- and rennet-induced) properties of deer milk and how they are impacted by typical processing treatments (e.g., homogenization and pasteurization). We identified unique features in the composition of deer milk, including being richer in protein, fat, calcium, zinc, iodine, branched-chain fatty acids, and α-linolenic acid than other ruminant milks. Different deer milk components displayed diverse variation patterns over the lactation cycle, many of which were different from those demonstrated in other ruminant species. Other physicochemical features of deer milk were identified, such as its markedly larger fat globules. Processing treatments were demonstrated to alter the structural and gelation properties of deer milk. Most of the gelation properties of deer milk resembled that of bovine milk more than ovine and caprine milks. This study furthers our understanding of red deer milk and will aid in its processing and applications in novel products.