LEE- Gıda Mühendisliği-Doktora

Bu koleksiyon için kalıcı URI

http://hdl.handle.net/11527/19294

Gözat

Yazar "Özçelik, Beraat" ile LEE- Gıda Mühendisliği-Doktora'a göz atma
  • Öge
    Formation of anthocyanin-rich black carrot extract loaded potato protein particles by ternary compressed CO2-ethanol-water mixture extraction and PGSS-drying
    (Graduate School, 2021-08-16) Düzgün Yavuz, Merve ; Özçelik, Beraat ; 506142501 ; Food Engineering
    Black carrot anthocyanins have importance for food industry as it is a natural colorant and possesses health beneficial effects regarding the functional food and beverages. Anthocyanins are conventionally extracted by using organic solvents such as methanol, acetone or water with small amount of hydrochloric acid or formic acid. These methods are problematic due to the residues of organic solvents remaining in extracts that are associated with food safety or due to the degradation of anthocyanins at high temperatures which required for acidified water extraction. Due to these problems, it is crucial to develop novel methods which are environmentally sustainable and efficient, resulting in high yields. The extraction using sub- and supercritical carbon dioxide (sc-CO2) has been growing as an alternative to conventional extraction, as it can potentially fulfill these demands. The anthocyanin- rich extracts are still very labile to different environmental conditions. Encapsulation or complexation with different biopolymers of bioactive compounds provides a good solution before the incorporation of these valuable compounds in food and beverages. Complex coacervation is one of the encapsulation methods which finds a widespread relevance in functional biomaterials consisting the food and beverage area. It is a physicochemical process that be conducted at mild temperatures without high pressures. The other process applied in this thesis for the purpose of complexation was Particles from Gas saturated Solutions–Drying.
  • Öge
    Potential of lactic acid bacteria fermentation as a strategy for valorisation and biotransformation of mushrooms
    (Graduate School, 2024-08-15) Sümer Ayar, Eda Nur ; Özçelik, Beraat ; 506172502 ; Food Engineering
    Consumers increasingly recognise the importance of healthy eating and the potential benefits of incorporating mushrooms into their diets. Known for their rich nutritional profile, mushrooms provide essential vitamins, minerals, fibre, and antioxidants, making them valuable plant-based food sources. They are also rich in bioactive compounds with anti-inflammatory, antioxidant, antitumor, antiviral, and antimicrobial properties, promoting health and reducing disease risks in humans. Among various bioactive components in mushrooms, phenolic compounds are particularly noteworthy. These compounds are considered significant secondary metabolites in mushrooms and are found in free and bound forms within food matrices. However, the bioaccessibility and bioavailability of bound phenolic compounds are lower than that of free phenolic compounds due to their covalent bonds to cell wall matrices, which prevent absorption in the small intestine. Additionally, mushroom production generates various by-products, which pose environmental and financial challenges due to their disposal. Innovative processing techniques are required to enhance the bioavailability of phenolic compounds and add value to mushroom by-products. Fermentation with lactic acid bacteria (LAB) is effective in this context. LAB fermentation not only extends the shelf life and improves sensory properties but also breaks down macronutrients such as carbohydrates and proteins. This alters the nutritional composition of the food and facilitates the transformation of bound phenolic compounds into more bioavailable forms, similar to free phenolic compounds. Through LAB fermentation, macronutrients are transformed, antioxidative peptides are released, and phenolic compounds are modified. This process enhances the health benefits of mushrooms by increasing the bioavailability of mushroom phenolics, making them more accessible for absorption and use by the body. Therefore, fermentation techniques can significantly improve mushrooms' use, health benefits, and by-products. Given this information, a research framework for this doctoral thesis explores modifying industrial mushroom wastes and specific extracted components, as well as mushrooms like L. edodes and La. deliciosus, which may become waste due to their short shelf life. The research plan is based on processing mushroom waste and mushrooms through LAB fermentation. The objectives of this doctoral thesis are: (i) to valorise the mushroom waste generated from bioactive substance extraction, modifying its structure and nutritional composition through fermentation with lactic acid bacteria; (ii) to ferment the mushrooms with lactic acid bacteria to facilitate the transition of phenolic compounds from bound to free form, altering the structure of L. edodes and La. deliciosus; (iii) to determine biotransformation of these phenolic compounds use analytical identification; (iv) to investigate the effects of LAB fermentation on the bioaccessibility and intestinal transport of mushroom phenolics using an in vitro gastrointestinal digestion model. To achieve these objectives, three different experimental studies (Chapters 3-5) were conducted within the scope of this thesis. The first study focused on the fermentation of L. edodes mushroom waste, L. edodes residue (LER), with lactic acid bacteria compared to L. edodes itself (LE), examining changes in its structure and nutritional composition for functional properties (Chapter 3). The second study was based on the changes in phenolic components, interactions with other metabolites, and the profiling of phenolic substances in fermented L. edodes and La. deliciosus (Chapter 4). Based on the previous chapter's findings, the third study examined phenolic components' bioaccessibility and antioxidant activity trends in an in vitro gastrointestinal digestion model.
  • Öge
    Proteins and bioactive peptides extraction from food wastes and their modification by different processes to produce functional food products
    (Graduate School, 2024-05-15) Şenol, Ezgi ; Özçelik, Beraat ; 506182503 ; Food Engineering
    Watermelon seeds (WMS) have valuable protein content and possess health beneficial effects regarding the functional foods. They generally comprise approximately 35-40% protein per weight, rendering them a significant protein reservoir for individuals adhering to vegetarian and vegan diets. Additionally, watermelon seeds encompass healthy fats, including monounsaturated and polyunsaturated fats, which contribute to heart health. Moreover, these seeds boast dietary fiber, facilitating digestion and promoting digestive well-being, alongside serving as a rich source of minerals like magnesium, iron, zinc, and potassium, essential for diverse bodily processes. In terms of health benefits, watermelon seed protein is a nutritious and sustainable plant-based protein source that offers various health benefits and a valuable addition to a post-workout or muscle-building diet. Protein and fiber in watermelon seeds can help promote satiety, which may aid in weight management by reducing overall calorie intake. While watermelon seed protein offers numerous health benefits, it's essential to consume them as a protein source for a balanced. Incorporating watermelon seed protein into the diet of people preferring vegan, vegetarian or healthy diet can be a delicious and convenient way to boost the protein intake and support overall health and well-being. Even though WMS are a potential protein source owing to their high protein content and the balanced amino acid composition, they are often discarded when eating the fruit and actually packed with nutrients, including protein. In terms of valuable contents of bioactive peptides, protein, amino acids and, WMS protein come close to soy protein, being the most broadly used plant protein source so far.