Development of Hydrophobically Modified Casein Derivative-Based Delivery System for Docosahexaenoic Acids by an Acid-Induced Gelation

하호경,우단비,이미령,이원재 한국축산식품학회 2023 한국축산식품학회지 Vol.43 No.2

Although omega-3 fatty acids including docosahexaenoic acid (DHA) contain various health-promoting effects, their poor aqueous solubility and stability make them difficult to be induced in dairy foods. The aims of this research were to manufacture casein derivative-based delivery system using acid-induced gelation method with glucono-σ-lactone and to investigate the effects of production variables, such as pH and charged amount of linoleic acid, on the physicochemical properties of delivery systems and oxidative stability of DHA during storage in model milk. Covalent modification with linoleic acid resulted in the production of casein derivatives with varying degrees of modification. As pH was reduced from 5.0 to 4.8 and the charged amount of linoleic acid was increased from 0% to 30%, an increase in particle size of casein derivative-based delivery systems was observed. The encapsulation efficiency of DHA was increased with decreased pH and increased charged amount of linoleic acid. The use of delivery system for DHA resulted in a decrease in the development of primary and secondary oxidation products. An increase in the degree of modification of casein derivatives with linoleic acid resulted in a decrease in the formation of primary and secondary oxidation products than of free DHA indicating that delivery systems could enhance the oxidative stability of DHA during storage in model milk. In conclusions, casein derivatives can be an effective delivery system for DHA and charged amount of linoleic acid played a key role determining the physicochemical characteristics of delivery system and oxidative stability of DHA.

Classification and Functuonal Properties of Processed Cheese

하호경,이미령,노치원,김진욱,이원재 경상대학교 농업생명과학연구원 2013 농업생명과학연구 Vol.47 No.6

Processed cheese is manufactured by mixing natural cheeses with emulsifying salts and other ingredients and heating under agitation to produce a homogeneous product. Processed cheese, processed cheese food, and processed cheese spread are classified in the US standards for processed cheese. The functional properties of processed cheese, such as firmness and meltability, are regarded as a quality indicator assessing overall cheese quality and consumer preference. Various analytical methods have been developed to determine the functional properties of processed cheese. In this review, the classification and functional properties of processed cheeses are described and analytical tools for evaluating the functional properties of processed cheese are discussed.

Cellular Uptake and Cytotoxicity of β-Lactoglobulin Nanoparticles: The Effects of Particle Size and Surface Charge

하호경,김진욱,이미령,전우진,이원재 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.3

It is necessary to understand the cellular uptake and cytotoxicity of food-grade delivery systems, such as β-lactoglobulin (β-lg) nanoparticles, for the application of bioactive compounds to functional foods. The objectives of this study were to investigate the relationships between the physicochemical properties of β-lg nanoparticles, such as particle size and zeta-potential value, and their cellular uptakes and cytotoxicity in Caco-2 cells. Physicochemical properties of β-lg nanoparticles were evaluated using particle size analyzer. Flow cytometry and confocal laser scanning microscopy were used to investigate cellular uptake and cytotoxicity of β-lg nanoparticles. The β-lg nanoparticles with various particle sizes (98 to 192 nm) and zeta-potential values (–14.8 to –17.6 mV) were successfully formed. A decrease in heating temperature from 70°C to 60°C resulted in a decrease in the particle size and an increase in the zeta-potential value of β-lg nanoparticles. Non-cytotoxicity was observed in Caco-2 cells treated with β-lg nanoparticles. There was an increase in cellular uptake of β-lg nanoparticles with a decrease in particle size and an increase in zeta-potential value. Cellular uptake β-lg nanoparticles was negatively correlated with particle size and positively correlated with zeta-potential value. Therefore, these results suggest that the particle size and zeta-potential value of β-lg nanoparticles play an important role in the cellular uptake. The β-lg nanoparticles can be used as a delivery system in foods due to its high cellular uptake and non-cytotoxicity.

산양유 단백질 분해물/키토올리고당 나노 전달체 제조 및 물리화학적 특성연구

하호경,김진욱,한경식,윤숭섭,이미령,이원재,Ha, Ho-Kyung,Kim, Jin Wook,Han, Kyoung-Sik,Yun, Sung Seob,Lee, Mee-Ryung,Lee, Won-Jae 한국유가공학회 2017 한국유가공기술과학회지 Vol.35 No.3

본 연구에서는 산양유 단백질 분해물과 키토올리고당을 이용하여 약 138~225 nm 크기를 지니는 구형의 나노 전달체를 성공적으로 제조하였다. 제조된 나노 전달체는 소수성 건강기능성 물질인 DHA와 레스베라트롤을 각각 ~22 mg/100 mL와 ~4.5 mg/100 mL 씩 포집가능하며, 제조 공정요인(예, TPP 농도, 산양유 단백질 분해물 농도, 키토올리고당 농도) 조절을 통해 입자 크기, 표면전하등과 같은 나노 전달체의 물리화학적 특성과 소수성 건강기능성 물질의 포집 효율을 조절할 수 있음을 알 수 있었다. 또한 산양유 단백질 분해물/키토올리고당 나노 전달체는 동결건조를 통해 분말화가 가능하기 때문에 식품 적용성이 뛰어나다. 결론적으로 본 연구에서 food-grade 물질인 산양유 단백질 분해물과 키토올리고당을 이용하여 제조한 나노 전달체는 저지방 및 무지방 유식품에 적용 가능한 무지방 기반(non-fat based)의 소수성 건강기능성 물질 전달체로 이용될 수 있을 것으로 기대된다. The aims of this study were to manufacture a hydrolyzed goat milk protein (HGMP)/chitosan ologisaccharide (CSO) nano-delivery system (NDS) and to investigate the effects of production variables, such as sodium tripolyphosphate (TPP), HGMP, and CSO concentration levels, on the formation and physicochemical properties of the NDS. An HGMP/CSO NDS was produced using the ionic gelation method at pH 5.5. Transmission electron microscopy and a particle size analyzer were used to determine the morphological and physicochemical properties of NDSs, respectively. The size of the HGMP/CSO NDS decreased from 225 to 138 nm as HGMP and CSO concentration levels decreased. The NDS had a positive surface charge, with a zeta-potential value of +23 mV. The encapsulation efficiency (EE) of docosahexaenoic acid was enhanced as the HGMP concentration level increased. Additionally, increasing the concentration level of CSO resulted in an increase in the EE of resveratrol. The HGMP/CSO NDS exhibited good physical stability during freeze-drying. Thus, our findings showed that the HGMP/CSO NDS was successfully manufactured and that HGMP and CSO concentration levels were key factors affecting the physicochemical properties of the NDS.

Physicochemical Characterization and Potential Prebiotic Effect of Whey Protein Isolate/Inulin Nano Complex

하호경,전나은,김진욱,한경식,윤숭섭,이미령,이원재 한국축산식품학회 2016 한국축산식품학회지 Vol.36 No.2

The purposes of this study were to investigate the impacts of concentration levels of whey protein isolate (WPI) and inulin on the formation and physicochemical properties of WPI/inulin nano complexes and to evaluate their potential prebiotic effects. WPI/inulin nano complexes were produced using the internal gelation method. Transmission electron microscopy (TEM) and particle size analyzer were used to assess the morphological and physicochemical characterizations of nano complexes, respectively. The encapsulation efficiency of resveratrol in nano complexes was studied using HPLC while the potential prebiotic effects were investigated by measuring the viability of probiotics. In TEM micrographs, the globular forms of nano complexes in the range of 10 and 100 nm were successfully manufactured. An increase in WPI concentration level from 1 to 3% (w/v) resulted in a significant (p<0.05) decrease in the size of nano complexs while inulin concentration level did not affect the size of nano complexes. The polydispersity index of nano complexes was below 0.3 in all cases while the zeta-potential values in the range of -2 and -12 mV were observed. The encapsulation efficiency of resveratrol was significantly (p<0.05) increased as WPI and inulin concentration levels were increased from 1 to 3% (w/v). During incubation at 37°C for 24 h, WPI/inulin nano complexes exhibited similar viability of probiotics with free inulin and had significantly (p<0.05) higher viability than negative control. In conclusions, WPI and inulin concentration levels were key factors affecting the physicochemical properties of WPI/inulin nano complexes and had potential prebiotic effect.

치즈 숙성 촉진 및 풍미 증진을 위한 최신 기술

하호경,Ha, Ho-Kyung 한국축산식품학회 2019 축산식품과학과 산업 Vol.8 No.1

Under-ice Measurements of Suspended Particulate Matters using ADCP and LISST-Holo

하호경,김용훈,이현정,황병준,주형민 한국해양과학기술원 2015 Ocean science journal Vol.50 No.1

Using a mooring package comprising an acoustic Doppler current profiler (ADCP) and holographic imaging system, a 1-day ice camp study was performed under the Arctic sea ice in the northern Chukchi Plateau to estimate vertical and temporal variations in total suspended particulate matter (SPM). In early August, the SPM in the upper mixed layer (~15 m and above) under sea ice reached up to about 100 mg l-1 even under the offshore regime. Results of both holographic and microscopic analyses showed that dominant constituents of this increased SPM were biogenic rather than lithogenic materials. Due to the highest melt and break-up rates of sea ice during the summertime, the export of particulate materials and ice algal communities embedded in the sea ice might significantly contribute to the increase in SPM. This study suggests that the combined effects of the increase in ice algal production and the decrease in ice and snow cover and multi-year sea ice extent could create favorable conditions for enhancing the concentration and flux of PM during the summertime.

Effects of suspended sediment concentration and turbulence on settling velocity of cohesive sediment

하호경,Jerome P.-Y. Maa 한국지질과학협의회 2010 Geosciences Journal Vol.14 No.2

Using a 5-MHz acoustic Doppler velocimeter (ADV),laboratory experiments were carried out to investigate the effects of suspended sediment concentration (SSC) and turbulence on the settling velocity (ws) of cohesive sediment. The measurement of ws with the Clay Bank sediment showed that ws increased non-linearly with SSC in the range of 300–700 mg L−1, and that turbulence can increase ws up to one order higher than ws for nonturbulent conditions. This turbulence effect can explain why ws derived by ADV is 1 to 3 orders higher than ws estimated by Owen tube where the ambient turbulence is totally blocked. When the turbulent shear stress was higher than about 0.14 Pa,however, it contributed to tear apart flocs and reduce ws. This study suggests that ADV is a useful tool to concurrently measure the instantaneous current velocities, SSC and ws in turbulence-dominant environments without breaking up flocs and disturbing ambient flow.

식품 소재를 이용한 나노전달체의 제조 및 유식품 적용에 관한 고찰

하호경,이원재 한국낙농식품응용생물학회 2018 Journal of Dairy Science and Biotechnology (JMSB) Vol.36 No.4

Nano-delivery systems, such as nanoparticles, nanoemulsions, and nanoliposomes, are carriers that have been used to enhance the chemical as well as physical stability and bioavailability of bioactive compound. Food-grade nano-delivery system can be produced with edible biopolymers including proteins and carbohydrates. In addition to the lowtoxicity, biocompatibility, and biodegradability of these biopolymers, their functional characteristics, such as their ability to bind hydrophobic bioactive compounds and form a gel, make them potential and ideal candidates for the fortification of bioactive compounds in functional dairy foods. This review focuses on different types of nano-delivery systems and edible biopolymers as delivery materials. In addition, the applications of food-grade nano-delivery systems to dairy foods are also described.

유청단백질 나노전달체의 기능적 특성

하호경(Hao Kyung Ha) 한국축산식품학회 2018 축산식품과학과 산업 Vol.7 No.2