Master Degree / Yüksek Lisans Tezleri

Permanent URI for this collectionhttps://hdl.handle.net/11147/3008

Browse

Filters

2022 - 20246

Settings

Author: search.filters.author.Harsa, Hayriye ŞebnemPublisher: search.filters.publisher.01. Izmir Institute of Technology

Search Results

Now showing 1 - 6 of 6
  • Master Thesis
    Development of Probiotic Bar With Microencapsulated Probiotics
    (01. Izmir Institute of Technology, 2024) İriçağıl, Zelihan; Baysal, Ayşe Handan; Harsa, Hayriye Şebnem; Harsa, Hayriye Şebnem; Baysal, Ayşe Handan; 03.08. Department of Food Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Bu çalışma, Saccharomyces boulardii CNCM-I745 ve Alkalihalobacillus clausii (N/R, O/C, SIN, T) gibi probiyotikleri mikroenkapsüle ederek, bu yararlı mikroorganizmaların stabilitesini ve canlılığını artırmayı amaçlayan bir probiyotik barın geliştirilmesini incelemektedir. Mikroenkapsülasyon, probiyotikleri koruyucu bir matris sağlayan lupin protein izolatı-ksantan gam-trehaloz kompleksi kullanılarak gerçekleştirilmiştir. Mikroenkapsüle edilmiş probiyotikler, glutensiz yulaf, hurma, fıstık ezmesi, kuru incir, ceviz, keten tohumu, tarçın ve tuz içeren bir bar formülasyonuna eklenmiştir. Nem içeriği, su aktivitesi, doku ve renk ölçümleri gibi fizikokimyasal analizler, barların kalitesini değerlendirmek için yapılmıştır. Ayrıca, probiyotiklerin canlılığını izlemek amacıyla 4°C'de 90 günlük bir depolama çalışması yürütülmüştür. Sonuçlar, mikroenkapsülasyonun probiyotiklerin stabilitesini ve hayatta kalma oranını önemli ölçüde artırdığını, canlı sayılarının depolama süresi boyunca 106 CFU/g üzerinde kaldığını ve Türk Gıda Kodeksi standartlarını karşıladığını göstermiştir. Özellikle, mikroenkapsüle edilmiş probiyotikler 90 günlük depolama süresince 1 log CFU/g'den az bir azalma gösterirken, serbest probiyotikler 3 log CFU/g'den fazla bir azalma göstermiştir. Çalışma ayrıca, probiyotiklerin in vitro gastrointestinal hayatta kalma oranlarını incelemiş ve mikroenkapsüle edilmiş probiyotiklerin simüle edilmiş mide ve bağırsak koşullarına karşı üstün direnç gösterdiğini ortaya koymuştur. Mikroenkapsülasyon süreci, depolama ve sindirim sırasında karşılaşılan zorlu çevresel faktörlerden koruyarak probiyotiklerin canlılığının korunmasını iyileştirmiştir. Bu araştırma, mikroenkapsülasyon tekniklerinin fonksiyonel gıdaların geliştirilmesindeki potansiyelini vurgulamakta ve yenilikçi, süt içermeyen probiyotik ürünler yaratma konusunda gıda endüstrisine değerli bilgiler sağlamaktadır.
  • Master Thesis
    Development of Aronia Based Vegan Nutritional Supplementation
    (01. Izmir Institute of Technology, 2024) Oruç, Yaren Tuğba; Harsa, Hayriye Şebnem; Harsa, Hayriye Şebnem; 03.08. Department of Food Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Fonksiyonel gıdalar, özellikle Kovid-19 salgını sonrasında değişen yaşam standartlarıyla birlikte küresel tüketici kitlesi ve gıda sektörü için büyük önem kazanmıştır. Aronia melanocarpa, biyoaktif madde içeriği yüksek, antioksidan içeriği ve zengin besin değeri olan, tüm dünyada yaygınlaşan ve bununla birlikte Türkiye'de de giderek yaygınlaşma hızını artıran bir meyvedir. Gerçekleştirilen çalışmada Aronia melanocarpa'nın süper meyve olarak seçilmesi nedenlerinden olan bu zengin ve faydalı içerik ile insanlığın uğraşmak zorunda kaldığı büyük ve ciddi sorunlara etkili olabilecek bir fonksiyonel gıda ürünü tasarlamak amaçlanmıştır. Hazırlanan ürünlerin fiziksel, kimyasal, mikrobiyolojik, raf ömrü ve duyusal özellikleri analiz edilmiş ve bunun yanında Aronya smoothie ürünü in vitro sindirim ve ADE engelleyici aktivite açılarından da incelenmiştir. Bu fonksiyonel ürünün kırmızı mercimekten ekstrakte edilen protein tozu ile protein seviyesi artırılmış ve Aronya toz karışım ürünü için %23,7, Aronya smoothie ürünü için ise %3,74 protein içeriği elde edilmiştir. Aronya smoothie ürününe uygulanan in vitro sindirim sonrası ürünün fenolik ve antioksidan özelliklerinde artış gözlenmiştir. Aronya smoothie ürününün dünya genelinde uğraşılan ciddi kronik sağlık sorunlarından olan hipertansiyon ve kalp hastalıkları üzerinde olumlu etkisi bulunan mekanizma ADE engelleyici aktivitesi %22 olarak tespit edilmiştir. Duyusal analiz sonucunda Aronya smoothie ürününün genel kabul edilebilirlik puanı 3,65 elde edilmiştir.
  • Master Thesis
    Effect of Different Storage Conditions on the Stability and Functionality of Dairy Powders: a Case Study With Labneh Production
    (01. Izmir Institute of Technology, 2023) Harsa, Hayriye Şebnem; Harsa, Hayriye Şebnem; 03.08. Department of Food Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Dairy powders are frequently used in the food industry because of their distinctive nutritional profile and long shelf life. They are popular food ingredients due to their texturizing, emulsifying, and nutritional properties. Nevertheless, each product exhibits distinct attributes that confer unique functionalities to them. The purpose of this study is to comprehend the impact of storage temperature and time on the functionality and stability of dairy powders and their use in labneh production to see how storage conditions of an ingredient affect final product attributes. The study employs four different dairy powders, namely Milk Protein Concentrate (MPC85), Skim Milk Powder (SMP), Whey Protein Concentrate 80 (WPC80), and Whey Protein Concentrate 80 -S (WPC80S). The mentioned powders were subjected to storage conditions of 10 °C, 25 °C, and 37 °C for a duration of 4 months. Prior to subjecting them to any temperature conditions, the analysis on day zero (D0) was performed. On a monthly basis dairy powder properties were assessed using color analysis using the L*, a*, b* system, particle size distribution, Fourier Transform Infrared Spectroscopy (FTIR), water activity, and turbidity analysis. After 4 months, the powders were removed from their storage environments and used in labneh recipes. For each resulted labneh sample, various analytical techniques were employed, including Color analysis, Fourier Transform Infrared Spectroscopy (FTIR), Texture analysis, Rheology measurements, and Sensory evaluations. The findings indicate that alterations in the functionality of dairy powders may greatly impact the quality of the final product.
  • Master Thesis
    Developing Spreadable Peanut Butters Incorporated With the Encapsulated Potential Psychobiotic Lactococcus Lactis C19.1 Strain
    (01. Izmir Institute of Technology, 2023) Harsa, Hayriye Şebnem; Harsa, Hayriye Şebnem; Arslan Tontul, Sultan; 03.08. Department of Food Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    In recent years, the partially processed food market has increased, partly due to the demand for fresh-cut or dried products. However, there is an increasing demand for foods enriched with physiologically active ingredients such as probiotics and prebiotics. From the nutrional point view, these two functional factors, have created a new market area for fruit and snack products. Peanuts have high nutritional value (24% protein, 45% fat and 13% fiber) as well as high amounts of thiamine and niacin). It is also known to reduce the risk of prostate, liver, colon and lung cancer and stress-related diseases. In this study, as a model bacteria Lactococcus lactis C19.1 strain isolated from Turkish cottage cheese has been impregnated with peanut and cashew nut butter after encapsulation. In the selection of the Lactococcus lactis strain, porbiotic and anti-stress properties were considered. To increase the viability of the strain, the encapsulation was carried by whey protein-xylan complex as the wall material. After encapsulation, the probiotic strain was added to the peanut and cashew nut butter formulation. In addition, in order to determine the encapsulation efficiency, it was impregnated to the butters the free cell form. The results revealed that encapsulation increased the shelf life stability of the psychobiotic cell. The shelf life of the peanut butters containing free cell of L. lactis was determined as 30 days that of 45 days in encapsulated cell containing samples. In addition, in vitro analyzes revealed that encapsulation protected probiotic cells in simulated gastrointestinal system and, the viability was between 106 – 107 CFU/g. However, the viability rate was found to be 105 in fort he free cell containing samples after digestion test. Cashews and peanut butters containing encapsulated cell came to the fore, as 105 CFU/g remained below the 106 CFU/g, which is the condition of being probiotic.
  • Master Thesis
    Development of Fermented Vegan Food Formulations With Improved Angiotensin-I Converting Enzyme Inhibitory (ace-I) Activity
    (01. Izmir Institute of Technology, 2022) Harsa, Hayriye Şebnem; Harsa, Hayriye Şebnem; 03.08. Department of Food Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Veganism has become popular in recent years and the demand for vegan products is increasing, especially due to the positive effects of plant-based diets on health. Since veganism can be defined as a diet or lifestyle that does not support the consumption of any animal food, protein-rich legumes occupy a large place in the daily diet of vegans. The health-promoting potential of probiotics in various forms has been recognized for years, and one of these health-promoting properties is their antihypertensive effect. In this context, the aim of this thesis is to develop some vegan food formulations, such as vegan mayonnaise-based salad dressings prepared using chickpea aquafaba and plant-based milk alternative (PBMA) fermented using lactic acid bacteria (LAB), showing antihypertensive effect. Microbiological, and quality characteristics and antioxidant properties of the formulations were determined. In addition, proteolytic activity and angiotensin-I converting enzyme inhibitory (ACE-I) activity experiments were carried out to control the antihypertensive properties of salad dressings. As a result, there are 107 CFU/ml bacteria in the final products. The quality characteristics of the formulations were compared with the literature. Consequently, the ACE-I activity of PBMA was enhanced by LAB fermentation and vegan mayonnaise was enriched with these high-value ingredients.
  • Master Thesis
    Functionalization of a Vegan Snack With Antimicrobial Edible Coating
    (01. Izmir Institute of Technology, 2022) Harsa, Hayriye Şebnem; Harsa, Hayriye Şebnem; 03.08. Department of Food Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Pomegranate peel is usually considered as a waste of fruit by many people, but it has quite high content of antioxidant, phenolic and antimicrobial compounds. The objective of this thesis is to observe the effect of edible film in vegan snack bar containing of dried fruits, nut and to functionalize the snack bar with enrichment of protein and antimicrobial content. The edible film was composed of 8% w/v of lentil protein extract, 15% w/w of pomegranate peel depends on protein content, 2% of pectin as a stabilizer and 0.5% of glycerol as a plasticizer. Application of coating was carried out by dipping method. Then, the coated vegan snack bar was dried at 40oC for 16 hours. The coated and uncoated bars were investigated in different conditions as 30% RH at 25 oC and 75% RH at 35 oC for 90 days. Optical properties, texture, total phenolic content, sensory, microbial and water activity analysis were determined to evaluate the impact of edible coating incorporation onto surface of the bar. The results showed that the coated bars have been preserved better than uncoated ones in terms of prevention of color change, microbial and textural properties, phenolic content and moisture loss in both conditions.