• 한국축산식품학회지
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• 제35권5호
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• pp.611-614
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• 2015

This study was performed to apply a protein film containing a natural antimicrobial compound to meat packaging and determine quality change of meat during storage. Proteins obtained from the by-products of food processing have been utilized as biodegradable film sources. Porcine meat and bone meal (MBM) is obtained during meat processing, and proteins from the MBM can be extracted and used as a film base material. Previously, an antimicrobial MBM film containing coriander oil (CO) was prepared and its physical properties and antimicrobial activity were characterized. In this study, the antimicrobial MBM-CO film was applied to beef patties packaging, and the microbial population and the degree of lipid oxidation were determined during storage at 4℃ for 15 d. The population of inoculated E. coli O157:H7 in the samples wrapped with the MBM-CO film was 6.78 log colony forming unit (CFU)/g after 15 d of storage, whereas the control had 8.05 Log CFU/g, thus reducing the microbial population by 1.29 Log CFU/g. In addition, retardation of lipid oxidation in the patties was observed during storage for the samples packaged by the MBM-CO film, compared with the control samples. These results suggest that the MBM-CO film can be useful for enhancing the quality of beef patties during storage.

• Food Science and Biotechnology
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• 제15권3호
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• pp.478-481
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• 2006

This study investigated the antimicrobial activity of soy protein isolate (SPI) film containing green tea extract (GTE, 1-4%, w/w) on dental caries-inducing bacterium (Streptococcus mutans), food pathogenic (Staphylococcus aureus, Escherichia coli 0157, Salmonella typhimurium), and spoilage (Pseudomonas aeruginosa) bacteria. The physical and mechanical properties of the SPI film containing GTE were also studied. The SPI film containing GTE (4%, w/w) exhibited good antimicrobial activity against S. mutans and S. aureus. The antimicrobial activity of the SPI film containing GTE increased against S. mutans as the concentration of GTE increased up to 4%(w/w). SPI films containing GTE showed lower tensile strength and elongation, and higher total soluble matter than those of control SPI film. Therefore, GTE can be used as one of antimicrobial agents for anti-dental caries and food packaging films.

• Food Science and Biotechnology
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• 제15권1호
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• pp.133-137
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• 2006

Wheat gluten-chitosan composite film (WGCCF) can prevent moisture migration and enhance the antimicrobial properties of gluten in intermediate-moisture foods like sandwiches. To mimic the structure of actual sandwich-type products we developed multi-layer food models, where moisture content and water activity differ. Water activity gradients direct moisture migration and therefore determine product characteristics and product stability. A 10% wheat gluten film-forming solution was mixed with chitosan film-forming solution (0-3%, w/w) and evaporated to generate WGCCF. Addition of 3% chitosan enhanced the mechanical properties of the film composite, lowered its water vapor permeability, and improved its ability to protect against both, Streptococcus faecalis and Escherichia coli, in a 24 hr sandwich test (reduction of 1.3 and 2.7 log cycles, respectively, compared to controls). Best barrier and antimicrobial performance was found for 3% chitosan WGCCF at pH 5.1. Film of this type may find application as barrier film for intermediate-moisture foods.

• KSBB Journal
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• 제17권4호
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• pp.350-356
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• 2002

다양한 식품의 미생물에 의한 변패를 억제하고 저장성을 높일수 있는 포장필름을 개발하기 위하여, 미생물이 생산하는 천연 항균성 물질을 흡착시킨 silica에 항균제로서 benzoic acid 및 일본산 항균성 필름 첨가제인 JP를 공동 첨가하여 항균성 LDPE 필름을 제조하였다. 천연 항균제로는 methanol 자화 방선균 MO-16과 MO-17이 생산한 항균제를 사용하였으며, 이 물질은 121$^{\circ}C$에서 5분간 열처리시에도 항균력이 유지되는 내열성이 확인되었다. 제조한 silica LDPE 필름의 미생물생육 억제효과를 검토한 결과 조분쇄한 돈육의 경우 포장하여 실온 및 4$^{\circ}C$에서 보존시 시판필름에 비해 미생물생육억제효과가 우수하였다. 고체배지에 제조필름을 첨가하여 E. coli 에 대한 항균효과를 검토한 결과 첨가량에 따라 항균효과가 우수한 것이 입증되었다. 제조필름으로 포장한 4종류의 식품에 대한 저장성을 검토한 결과 시판필름에 비해 저장성이 우수한 것이 확인되었으며 특히 양송이 및 토마토에 대한저장효과가 우수하였다.

• Environmental Engineering Research
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• 제13권3호
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• pp.136-140
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• 2008

$TiO_2$ photocatalyst has been known to exhibit a notable disinfecting activity against a broad spectrum of microorganisms. A lot of commercial $TiO_2$ photocatalyst products have been developed for antimicrobial purposes. However, a standard method has not yet been proposed for use in testing antimicrobial activity. In this study, we developed a $TiO_2$ photocatalytic adhesion test method with film as the standard testing method for the evaluation of antimicrobial activity. This method was devised by modifying the previous antimicrobial products test method, which has been widely used, and considering the characteristics of $TiO_2$ photocatalytic reaction. The apparatus for testing the antimicrobial activity was composed of a Black Light Blue (BLB) lamp as UV-A light source, a Petri dish as the cover material, and a polypropylene film as the adhesion film. The standard $TiO_2$ photocatalyst sample, Degussa P25 $TiO_2$ - coated glass, could only be used once. The optimal initial concentration of the microorganism, proper light intensity, and light irradiation time were determined to be $10^6$ CFU/mL, 1.0 mW/$cm^2$, and 3 hr, respectively, for testing and evaluating antimicrobial activity on the $TiO_2$ surface.

• Journal of Microbiology and Biotechnology
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• 제17권3호
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• pp.520-523
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• 2007

Edible films of gelatin and com zein were prepared by incorporating nisin to the film-forming solutions. Com zein film with nisin of 12,000 IU/ml had an increase of 11.6 MPa in tensile strength compared with the control, whereas gelatin film had a slight increase with the increase of nisin concentration added. Water vapor permeability for both com zein and gelatin films decreased with the increase of nisin concentration, thus providing a better barrier against water. Antimicrobial activity against Listeria monocytogenes increased with the increase of nisin concentration, resulting in 1.4 log cycle reduction for com zein film and 0.6 log cycle reduction for gelatin film at 12,000 IU/ml. These results suggest that incorporation of nisin into com zein and gelatin films improve the physical properties of the films as well as antimicrobial activity against pathogenic bacteria during storage, resulting in extension of the shelf life of food products by providing with antimicrobial edible packaging films.

• Food Science and Biotechnology
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• 제17권6호
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• pp.1203-1206
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• 2008

Silk fibroin (SF) film containing catechin was prepared and the antimicrobial activity as well as physical property of the film was examined. Tensile strength of the SF film decreased with increasing concentration of catechin, and water vapor permeability of the film decreased. The film's antimicrobial activity against Escherichia coli O157:H7 increased with increasing catechin concentration. Sausage samples were inoculated with E. coli 0157:H7 and Listeria monocytogenes, and the sausage packaged with the SF film containing catechin had a decrease in the populations of E. coli O157:H7 and L. monocytogenes by 0.83 and 0.85 log CFU/g after 12 days of storage, respectively, compared to the control. In addition, the sausage had a better quality than the control regarding lipid oxidation. Our results indicate that sausages can be packed with the SF film containing catechin to extend shelf life.

• KSBB Journal
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• 제15권6호
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• pp.600-604
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• 2000

다양한 식품의 미생물에의한 변패를 억제하고 저장성을 높 일수 있는 포장필름을 개발하기위하여, 미생물이 생산하는 천연 항균성 물질을 홉착시킨 합성 세라믹올 첨가하여 세라 믹 LDPE 필륨을 제조하였다. 천연 항균제로는 methanol자화 방선균 MO-16 및 MO-17균이 생산한 항세균제와 새로이 분 리한 방선균 No. 31이 생산한 항진균제를 사용하였다. 방선 균 No. 31이 생산한 항진균성 불질은 배양 4일째 항균효과가 우수하였으며, $121^{\circ}C$에서 15분간 열처리시에도 항균력이 유 지되는 내열성이 확인되었다. 제조한 세라믹 LDPE 필름의 미생불 생육 억제효과를 검토한 결과 조분쇄한 돈육의 경우 포장하여 실온 및 $4^{\circ}C$에서 보존시 시판필름에 비해 미생물 생육 억제효과가 우수하였다. 고제배지에 제조필름을 첨가하 여 E. coli에 대한 항균효과를 검토한 결과 첨가량에 따라 항 균효과가 우수한 것이 입증되었다 제조펼름으로 포장한 6종 류의 식품에 대한 저장성을 검토한 결과 시판필름에 비해 저 장성이 우수한 것이 확인되었으며 특히 양송이에 대한 저장 효과가 우수하였다.

• Journal of Microbiology and Biotechnology
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• 제14권6호
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• pp.1303-1309
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• 2004

In order to extend shelf-life of the packaged or coated foods, an antibacterial edible film was developed. Antimicrobial activities of 9 bacteriocin-like substance (BLS)­producing strains were evaluated after growing them on defatted soybean meal medium (DSMM). Bacillus subtilis was selected among those, because it showed the biggest inhibition zone against 6 problem bacteria in food. The antimicrobial edible film, containing $0.32\%$ of BLS, was produced from the fermented soybean meal with B. subtilis at the optimum condition of pH 7.0-7.5 and $33^{\circ}C$ for 33 h. The antimicrobial activity of the film was over $50\%$ of the maximum activity after film production with heat treatment at $90^{\circ}C$ and pH adjustment to 9. When the soy protein film with BLS was applied on the agar media containing E. coli, the growth inhibition was much higher than the ordinary soy protein film. These results indicate that the soy protein film with BLS from B. subtilis can be used as a new packaging material to extend the shelf-life of foods.

• 한국식품저장유통학회지
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• 제12권4호
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• pp.323-328
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• 2005

천연 항균성 peptide인 polylysine을 이용한 항균성 포장재의 개발을 위한 기초자료를 얻기 위하여 polyamide 수지를 기반으로 하는 제조조건을 검토하고 두부를 대상식품으로 하여 병원성 및 부패 관련 미생물에 대한 항균활성을 확인하였다. Polylysine 제조조건에 있어서는 polylysine, polyamide의 농도와 코팅필름의 두께에 따라 항균활성에 큰 차이를 보였으나, $1.0\%$ 이상의 polylysine, $40\%$ polyamide, $50\;{\mu}m$ 이상의 필름 두께로 제조한 필름에 상대적으로 가장 높은 항균활성을 나타내었다. Polylysine의 용출량은 코팅된 필름을 멸균수에서 7일간 침지시킨 결과 침지 3일 까지 최대 약 $20\;{\mu}g/mL$의 농도를 나타낸 후 평형에 도달하였다. 코팅 필름의 항균활성은 초기 생균수 $4.8{\times}10^5\;CFU/mL$인 B. cereus에 대해 대조구에 비해 침지 7일 후 최대 105 CFU/mL수준의 감균효과를, 그리고 초기 생균수 $6.8{\times}10^5\;CFU/mL$인 K. pneumoniae에 대해서는 대조구에 비해 침지 7일 후 최대 $10^2\;CFU/mL$ 수준의 감균효과를 나타내어 polylysine 코팅 필름의 항균성 포장재로서의 활용 가능성을 확인 할 수 있었으며 polylysine 코팅 필름을 상업적으로 적용하기 위해서는 저농도의 두꺼운 필름보다는 고농도의 얇은 필름이 미생물의 증식을 저해하는데 효과적이라고 판단된다. 또한 필름으로부터 polylysine 용출을 용이하도록 하기 위한 연구가 추가로 연구되어야 하겠다.