초록 ▼

Ⅳ. 연구개발결과
- 시판 냉동 다진 마늘의 품질 분석, 대파, 마늘의 동결 및 해동 조건별 품질 분석과 대파, 마늘의 냉동 및 저장기간조건에 따른 품질 특성을 분석하였음.
- 물분자 모델링을 통한 적정 전자기장 주파수 구명 및 전자기장 급속동결장치 제작 및 마늘, 절단무에 대한 효과 구명하였음.
- 과냉각을 이용한 급속냉동 식품동결장치 설계 및 제작(특허출원:10-2014-0148187), 저온챔버 제습장치 설계 및 제작(특허출원:10-2014-0148298), 전자기장을 이용한 과냉각 및 급속동결 요인실험장치 제

Ⅳ. 연구개발결과
- 시판 냉동 다진 마늘의 품질 분석, 대파, 마늘의 동결 및 해동 조건별 품질 분석과 대파, 마늘의 냉동 및 저장기간조건에 따른 품질 특성을 분석하였음.
- 물분자 모델링을 통한 적정 전자기장 주파수 구명 및 전자기장 급속동결장치 제작 및 마늘, 절단무에 대한 효과 구명하였음.
- 과냉각을 이용한 급속냉동 식품동결장치 설계 및 제작(특허출원:10-2014-0148187), 저온챔버 제습장치 설계 및 제작(특허출원:10-2014-0148298), 전자기장을 이용한 과냉각 및 급속동결 요인실험장치 제작, 냉동농산물 표면관찰장치 제작하였음.
- 물의 과냉각과 냉동속도의 상관관계 분석, 냉동온도에 따른 마늘 추출물의 생리활성 변화 분석, 농산물 과냉각온도 및 동결점 분석, 마늘의 급속냉동시 과냉각 효과 분석, 전자기장을 이용한 마늘의 과냉각 및 급속냉동 요인실험 및 과냉각 급속동결 실험 수행 및 효과 검증하였음.
- 동결 마늘 대파를 위한 세척 전처리 조건 구명, 조리용도별 및 절단 전처리한 동결 마늘 대파의 품질특성 분석, 가공 전처리별 동결 마늘 대파 품질특성 조사하였음.
- 동결 마늘 대파와 생마늘, 생대파의 조리 후 관능적 특성 비교, 마늘 대파 이용 동결 편의제품 개발, 동결 마늘 대파 냉동 편의제품 현장실증 시험하였음.
- 마늘 및 대파의 냉동특성을 조사하고, 포장방법에 따른 제품의 품질을 조사한바 파우치형태나 진공포장방법 보다는 트레이형의 포장재를 사용하여 내용물을 충진한 후 커버필름을 사용하여 포장하는 방법이 우수함을 확인하였음.
- 이들 제품의 커버필름으로 방담성을 갖는 생분해성 포장재를 기조로 하고 여기에 나노 충진제를 혼합하여 항균성 및 자외선 차단성, 방담성의 기능성을 갖는 포장 필름을 개발하였음.

Abstract ▼

Evaluation of quality characteristics of korean and chinese frozen chopped garlic
This study investigated quality characteristics of commercial frozen chopped garlic. We collected six kinds of commercial frozen chopped garlic, four of which were domestic and the remaining two made in China. The m

Evaluation of quality characteristics of korean and chinese frozen chopped garlic
This study investigated quality characteristics of commercial frozen chopped garlic. We collected six kinds of commercial frozen chopped garlic, four of which were domestic and the remaining two made in China. The moisture contents and drip loss of domestic frozen chopped garlic were significantly lower than those of Chinese garlic. Drip loss was positively correlated with moisture content (r=0.918, P<0.01). Total pyruvate contents of frozen chopped garlic ranged from 118.69±5.97∼224.81±9.92 μmol/g in domestic garlic and 75.27±5.91∼79.35±1.79 μmol/g in Chinese garlic. Allicin contents of frozen chopped garlic ranged from 8.91±0.34∼13.09±0.35 mg/g in domestic garlic and 5.91±0.08∼6.05±0.27 mg/g in Chinese garlic. Total thiosulfinate content of commercial frozen chopped garlic ranged from 0.60±0.07∼1.33±0.12 optical density/g. Total thiosulfinate content of commercial frozen chopped garlic was positively correlated with allicin content (r=0.892, P<0.01). Flavor patterns of commercial frozen chopped garlic measured by an electronic nose showed no difference between domestic and Chinese garlics.
Evaluation of quality characteristics of frozen welsh onion with different freezing and thawing conditions
In trunk, when welsh onion was frozen at immersed liquid freezer(ILF, -40℃), hardness and Hunter L value of thawed welsh onion were most similar to raw materials. In leaf, when welsh onion was frozen at ILF, Hunter a value of thawed welsh onion was most similar to raw materials and was thawed at room-temperature(20℃), Hunter b value was most similar to raw materials. Drip loss was the lowest when freezing at ILF or thawing at room-temperature. Total aerobic bacteria counts of thawed welsh onion were the lowest when freezing at -20℃ or using water-thawing. Flavor patterns of thawed welsh onion were grouped according to three freezing conditions.
Evaluation of quality characteristics of frozen garlic with different freezing and thawing conditions
△E values was most similar to freezing at ILF or thawing at room-temperature and using water-thawing. The contents of total pyruvate of frozen garlic was the highest when freezing at ILF or thawing at room-temperature in except for the Uiseong cultivar. The contents of total free sugar in the Uiseong cultivar were detected fructose. Sucrose were detected from another cultivars. The contents of organic acid of frozen garlic were detected citric acid and succinic acid. Flavor patterns of garlic freezing at ILF were grouped with fresh garlic according to freezing conditions in except for the Danyang cultivar and the Daeseo cultivar.
Evaluation of quality characteristics of welsh onion during frozen storage
Drip loss of frozen welsh onion was the lowest in freezing at ILF. Drip loss and the numbers of aerobic bacteria of frozen welsh onion were decreased according to the increasing of storage period. In trunk and leaf of frozen welsh onion, △E values were increased according to the increasing of storage period. The contents of total pyruvate of frozen welsh onion were decreased according to the increasing of storage period. The contents of total pyruvate of frozen welsh onion was the highest in freezing at ILF. The contents of total free sugar were detected fructose and glucose. The contents of total free sugar of frozen welsh onion were no significant difference according to storage period.
Evaluation of quality characteristics of chopped and sliced garlic in the Daeseo and Uiseong cultivar during frozen storage
Drip loss and the numbers of aerobic bacteria of frozen garlic were decreased according to the increasing of storage period. Drip loss and the numbers of aerobic bacteria of frozen garlic was the lowest in freezing at ILF. Lightness of frozen garlic were decreased according to the increasing of storage period. However, Redness and yellowness of frozen garlic were increased according to the increasing of storage period. The hardness of frozen garlic was increased according to the increasing of storage period. The hardness of frozen garlic was the highest in freezing at ILF. The contents of total pyruvate and allicin of frozen garlic were decreased according to the increasing of storage period. The contents of total pyruvate of frozen garlic was the highest in freezing at ILF.
The supercooling of garlic and welsh onion and using electromagnetic heating and development of rapid-freezing technology
This study was conducted to enhance the conventional quick freezer not only using the low temperature coolant but also using supercooling state. To make short the passing time through the zone of maximum ice crystal formation, in the present investigation, supercooling process was included before quick freezing. Every food has different nucleation points, so we adopt the silicone oil as a coolant for the supercooling state to change the temperature easily. Additionally, for the quick freezing, we used liquid nitrogen spray. With the heat exchange type precooler using silicone oil, the temperature of the chamber was easily changed for supercooling. In particular, the results of freezing test of garlic indicated that this system had better quality in the hardness after it thawed, compared to conventional freezing method. Before quick freezing, if the food experience supercooling state, the time from nucleation to -5°C frozen state (the maximum ice crystal formation zone) will be shorter than just quick frozen one. The combination of heat exchanger type supercooler and liquid nitrogen sprayer should be promising technology to improve physicochemical qualities of frozen foods.
During the freezing of agro-food, ice grows fast in the zone of maximum ice crystal formation, from the freezing point to five degrees below the freezing point. Quick freezing makes smaller ice crystals than slow freezing. The frozen food with small ice crystals has better quality than that with big ice crystals, and quick freezing usually used for frozen food. In this study, we used four kinds of freezing to change the temperature difference between unfrozen layer and freezing front. To make short the freezing time of the layers in food, we used electromagnetic heating during quick freezing. A little amount of electromagnetic heating makes the layers in the food unfrozen until the phase transition of the freezing front is finished. To compare the hardness, we used 27.12 MHz RF (Radio Frequency) heating to thaw the frozen samples. This result shows that electromagnetic heating can be used to upgrade the effect of quick freezing.
Quick freezing is widely used in commercial food storage. Well-known freezing techniques such as individual quick freezing require a low-temperature coolant and small cuts for the heat-transfer efficiency. However, the freezing method for bulk food resembles techniques used in the 1970s. In this study, electromagnetic (EM) heating was applied to improve the quick freezing of bulk food. During freezing, the surface of food can be rapidly cooled by an outside coolant, but the inner parts of the food cool slowly owing to the latent heat from the phase change. EM waves can directly heat the inner parts of food to prevent it from freezing until the outer parts finish their phase change and are cooled rapidly. The center temperature of garlic cloves was probed with optical thermo sensors while liquid nitrogen (LN) was sprayed. When EM heating was applied, the center cooling time of the garlic cloves from freezing until -10°C was 48 s, which was approximately half the value of 85 s obtained without EM heating. For the white radish cubes, the center cooling time was also improved, from 288 to 132 s. The samples frozen by LN spray with EM heating had a closer hardness to the unfrozen samples than the samples frozen by LN only.
The commercialization and used cooking of frozen garlic and welsh onion
This study was carried out to promote the products that garlic and welsh onion of washing, dehydration, cutting, packing and freezing. That was developed a step-by-step processing that can be long-term preservation, hygienic and high-quality for frozen convenience food.
The results are as follows.
Washing pretreatment and packing method of garlic
We were peel off garlic, the next the first with tap water to washing secondary, tertiary than remove the faucet after washing, dehydration, grinding, packaging and commercialization was rapidly frozen at –40 ℃. Garlic chopped are used in the home was packed with PP materials per 200g, commercial as prepared with 1kg.
Washing pretreatment and packing method of welsh onion
We were peel off welsh onion, then the first and the secondary washing with tap water, than tertiary washing with air bubbles, rinse, dehydration and cooking were cut by use and commercialize packaged frozen at –18∼-40℃. Slice welsh onion are used in the home was packed with PET materials per 200g, commercial as prepared with 1kg.
We compared a garlic and welsh onion flavor components analysis by GC-MS changes according to fresh, frozen, freeze-drying and hot air drying processing methods. Fragrance ingredient of garlic is fragrant ingredients were similar pattern, depending on the processing method, and was a quantitative difference. Welsh onion had a quantitative differences and flavor components patterns according to the processing method.
We analyzed of the characteristics of the fresh and frozen welsh onions by cooking method that the white part of the stem at 80 ℃ in salt (NaCl) 1% concentration was the highest value of L, the green part of green leaf -a this also was the highest value.
We cooked pizza and Kimchi(cabbage) with fresh and frozen garlic, when these sensory evaluation showed no significant difference in the taste. We cooked gomtang(beef-bone soup) and nureumjeok(pan-fried brochette) with fresh and frozen welsh onion when these sensory evaluation showed no significant difference in the taste.
In order to commercialize the garlic and welsh onion frozen convenience food products, processors field demonstration was performed at product is frozen welsh onions at Jindochungjengfoodvalley agricultural incorporated company in Jindo-gun. Frozen chopped garlic products was carried out demonstration at Handeul combined entity in Haenam-Gun. And we were reviewing these products about the possibilities that can be commercialized in the processing industry.
Preparation and characterization of sodium carboxymethyl cellulose/cotton linter cellulose nanofibril composite films
Crystalline cellulose nanofibril (CNF) was isolated from cotton linter pulp using an acid hydrolysis method and used as a filler to reinforce sodium carboxymethyl cellulose (CMC) film. The CNF was in rod shape with the diameter of 23-38 nm and the length of 125-217 nm and crystallinity index (CI) was 0.89. The effect of CNF concentration (1, 3, 5 and 10 wt% based on CMC) on the optical, morphological, mechanical, water vapor barrier, surface hydrophobicity, and thermal properties of the nanocomposites were studied. The CNF was evenly distributed in the polymer matrix to form smooth and flexible films indicating the CNF is highly compatible with the CMC. The tensile strength (TS) and elastic modulus (EM) of CMC film increased by 23% and 27%, respectively, while the elongation (E) decreased by 28% with 5 wt% of CNF inclusion. The WVP of CMC film decreased at low content of CNF, and increased with increase in CNF content, then decreased but to the same level of the control CMC film with the inclusion of 10 wt% of CNF. Transparency of CMC film decreased slightly from 87.7% to 86.2% with 5 wt% of CNF. The CMC/CNF composite films have a high potential to be used as an edible coating or packaging films for the extension of shelf life of fresh and minimally processed fruits and vegetables.
Amino acid mediated synthesis of silver nanoparticles and preparation of antimicrobial agar/silver nanoparticles composite films
Silver nanoparticles (AgNPs) were synthesized using amino acids (tyrosine and tryptophan) as a reducing and capping agent and they were incorporated into the agar to prepare antimicrobial composite films. The agar/AgNPs nanocomposite films were characterized by UV-visible spectroscopy, FE-SEM, FT-IR, and thermogravimetric analysis. The influence of reinforcement of AgNPs on the morphology, thermal stability, mechanical, water vapor barrier, water contact angle, and antibacterial properties of the agar-based films were investigated. The AgNPs solutions were bright yellow and brownish yellow in color when reduced by tyrosine and tryptophan, respectively, and they exhibited characteristic absorption peak for Ag at 420 nm. The absorption peaks showed a red shift to ~434 nm after forming composite with agar, which indicated the interaction of AgNPs with agar. XRD data demonstrated the crystalline structure of AgNPs with dominant (111) facet. Apparent surface color and transmittance of agar films were greatly influenced by the AgNPs. FTIR spectra did not show any changes in the chemical structure of agar after AgNPs reinforcement. The incorporation of AgNPs into agar did not exhibit any change in thermal stability, moisture content, and water vapor permeability. The water contact angle, tensile strength, and modulus decreased slightly, on the contrary, elongation at break increased after AgNPs incorporation. The agar/AgNPs nanocomposite films possessed strong antibacterial activity against Listeria monocytogenes and Escherichia coil. The agar/AgNPs film could be applied to the active food packaging by controlling the food-borne pathogens.
Preparation and application of agar/alginate/collagen ternary blend functional food packaging films
Ternary blend agar/alginate/collagen (A/A/C) hydrogel films with silver nanoparticles (AgNPs) and grapefruit seed extract (GSE) were prepared. Their performance properties, transparency, tensile strength (TS), water vapor permeability (WVP), water contact angle (CA), water swelling ratio (SR), water solubility (WS), and antimicrobial activity were determined. The A/A/C film was highly transparent, and both AgNPs and GSE incorporated blend films (A/A/C^AgNPs and A/A/C^GSE) exhibited UV-screening effect, especially, the A/A/C^GSE film had high UV-screening effect without sacrificing the transmittance. In addition, the A/A/C blend films formed efficient hydrogel film with the water holding capacity of 23.6 times of their weight. Both A/A/C^AgNPs and A/A/C^GSE composite films exhibited strong antimicrobial activity against both Gram-positive (L. monocytogenes) and Gram-negative (E. coli) food-borne pathogenic bacteria. The test results of fresh potatoes packaging revealed that all the A/A/C ternary blend films prevented forming of condensed water on the packaged film surface, both A/A/C^AgNPs and A/A/C^GSE composite films prevented greening of potatoes during storage. The results indicate that the ternary blend hydrogel films incorporated with AgNPs or GSE can be used not only as antifogging packaging films for highly respiring fresh agriculture produce, but also as an active food packaging system utilizing their strong antimicrobial activity.
Effects of preparation methods on the properties of poly(butylene adipate-co-terephthalate) films
Poly(butylene adipate-co-terephthalate) (PBAT) films were prepared with four different preparation methods and the effects of processing methods on physical, mechanical, and structural properties of PBAT films were studied. The films were characterized by UV-visible spectroscopy, FT-IR, XRD, and thermogravemetric analysis. All the films were white in color and exhibited high UV-barrier property. The film prepared by solvent casting (SC) method was less transparent than the other films. No structural change was observed among the PBAT films, though the films prepared at high temperature exhibited a higher degree of crystallinity. The extrusion-cast (EC) film exhibited the highest tensile strength, while the solvent-cast (SC) film had lowest TS. The water vapor permeability and water contact angle did not affected by the processing methods. The degree of crystallinity of the EC films was higher than the other films.