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In recent years, food ingredients rich in bioactive compounds have emerged as candidates to prevent excess adiposity and other metabolic complications characteristic of obesity, such as low-grade inflammation and oxidative status. Among them, fungi have gained popularity for their high polysaccharide content and other bioactive components with beneficial activities. Here, we use the C. elegans model to investigate the potential activities of a Grifola frondosa extract (GE), together with the underlying mechanisms of action. Our study revealed that GE represents an important source of polysaccharides and phenolic compounds with in vitro antioxidant activity. Treatment with our GE extract, which was found to be nongenotoxic through a SOS/umu test, significantly reduced the fat content of C. elegans, decreased the production of intracellular ROS and aging-lipofuscin pigment, and increased the lifespan of nematodes. Gene expression and mutant analyses demonstrated that the in vivo anti-obesity and antioxidant activities of GE were mediated through the daf-2/daf-16 and skn-1/nrf-2 signalling pathways, respectively. Taken together, our results suggest that our GE extract could be considered a potential functional ingredient for the prevention of obesity-related disturbances.

Milk phospholipids and non-polar lipids can form conjugations with antioxidants and starches, in the matrices of phytosomes and milk lipid-starch complexes, respectively. In addition to complexation, milk lipids also interact with starches in food matrices, leading to physiochemical changes of associated foods. Milk lipids possess neutral colour, taste, odour, natural, clean-label, and non-allergic. However, there has been little research on interactions or complexes between milk lipids and other food components when milk lipid was used as an ingredients in different food matrices. This thesis focuses on the extraction of bovine milk phospholipids from dairy products, purification of phospholipids, and preparation of vitamin C and E phytosomes in comparison with liposomes, followed by bovine milk phospholipid/triacylglycerol dispersions. Subsequently, non-polar lipids were used to prepare milk lipid-starch complexes in two kinds of food matrices: firstly bread and secondly starch gels. In the final research chapter, starch gel-stabilized milk fats were investigated in terms of lipid digestibility. The phytosomes were made by food-grade ethanol evaporation, and were verified by FTIR, DSC, UV and CI. In vitro models were used to measure the phospholipid digestibility and cellular uptake. Amylose-lipid complexes were prepared by thermal methods. The complexes were then verified by spectroscopy analysis. Starch and milk fat digestibility was determined by in vitro assays and simulated by a multi-step reaction model. The results on milk phospholipids showed that the polar heads of milk phospholipids in phytosomes interacted with hydroxyl groups of ascorbic acid resulting in the shifting of major bonds in the phosphatidyl residues in phospholipids, and therefore, milk phospholipid-based phytosomes had greater encapsulation efficiency and in vitro digestion stability than liposomes. Additionally, in opposition to triacylglycerol, milk phospholipids showed greater lipid digestibility and exhibited antioxidant activity due to differences in molecular and hydrocolloid structure. Therefore, milk phospholipids have potential application in fortification of foods including infant formulas. In contrast to milk phospholipid-based complexes, milk fats can interact and complex with corn, rice and wheat starches in food matrices. When milk fats were hydrolysed by fungal lipase, they formed starch-fatty acid complexes during baking, delaying bread firming rate and extending shelf-life due to reduced re-crystallisation of amylopectin. Hence, lipase treatment of milk fats offers a feasible way to improve both textural and physiological properties of bread. Also, milk fats-amylose conjugation can be produced by cooking at 95˚C, providing a practical method to lower the glycaemic response of starchy foods, reducing starch digestibility by 19% in corn starch, 17% in wheat starch, and 25% in rice starch. In addition to conjugation with milk fats, starch particles can also be used to stabilize milk fat emulsions. In vitro digestion showed that the lipolysis reaction speed and extent of starch gel-stabilized milk fats were two – three-fold that of milk fat dispersion, confirming the calculation by the multi-step enzymatic reaction model. This indicates the possibility to regulate lipid digestibility by designing starch-based matrices. Beginning with bovine buttermilk, membrane filtration was proposed to manufacture enriched milk phospholipid products (11 – 20 g polar lipids/100 g products), with the current, best available process efficiency. Supercritical fluid extraction was an effective, food-compatible method to produce high purity (65 – 90%) milk phospholipid products. Overall, this thesis demonstrates the structure-property-functionality relationship of milk phospholipids/lipids in several food matrices. This thesis provided novel approaches to the further use of milk lipids as functional food ingredients, such as vesicles (Chapter 4), antioxidants for infant formulas (Chapter 5), bakery product textural improvers (Chapter 6), glycaemic index reducers of starchy foods (Chapter 7), and lipophilic compound carriers using starch-stabilized milk lipid matrices (Chapter 8). Last research chapter (Chapter 9) offered practical knowledge to develop new product and processes using milk phospholipids. In future research, besides milk phospholipid neuro-functionality, milk lipid interactions with proteins and phenolic compounds should provide interesting research questions to explore.

Food is one of the great pleasures of life. However, due to cultural backgrounds and physical conditions, the same food is not suitable for all consumers. Peanuts, dairy products, and wheat can be deadly for people with food allergies. These consumers must carefully check the ingredients of all of their food. This article outlines a system that combines product labeling and mobile technology to help those with food allergies and food intolerances easily manage their diet and protect their health. With this new system, a user with dietary restrictions only needs to scan a label barcode with a mobile phone app to quickly assess a food product’s appropriateness for their needs. This system not only provides users with a functional, time-saving solution, it will also provide peace of mind to improve their quality of life.

An unexplored area in research is addressing how retorted food ingredients interact with retort packaging's oxygen barrier. Ten common food ingredients (whey protein isolate, soy protein isolate, bovine gelatin, fish gelatin, high molecular weight fish gelatin, water, air, oil, potato starch, and hydroxypropyl methylcellulose) were assessed to find their effect on the barrier properties of CPP, PET, and high barrier commercial retort pouches. OxySense Gen III 300 and Mocon OxTran 2/21 were used to evaluate the samples. CPP pouches were first assessed with the OxTran 2/21 and indicated that treatments affected the OTR's of the film materials. However, results from the OxySense show that there is not a difference in oxygen ingress over time. Oil increased film permeability on all pouch materials tested and allowed for a higher OTR and faster oxygen ingress.

The potential applications of chickpea proteins (Cicer arietinum L. cv Kaniva) as food ingredients have been investigated and presented in three major parts of this thesis. The first part identified different extraction conditions and their effects on the extraction yield and characteristics of the isolated proteins. The second part defined the functional properties of these isolated proteins and relevant factors affecting their behaviour. The third part investigated the effects of chemical and enzymatic modifications on the composition, structural characteristics, functional and flow properties of the modified proteins, particularly, their rheological properties in wheat flour dough systems.