초록 ▼

Ⅳ. 연구개발결과
방충물질 후보군으로 선정한 11가지 식물 정유 및 이들을 구성하는 단일성분 중 대상해충에 대해 우수한 방충력을 보인 상위 4가지 물질은 마늘 정유, 양파 정유, 알릴 디설파이드, 알릴메르캅탄으로 확인되었다. 이들을 방충물질로 사용하여 제작한 방충다층필름은 방충물질 무처리 필름(대조군)에 비하여 매우 우수한 화랑곡나방 유충의 침투 억제율을 보였고 특히 5% 알릴 디설파이드 함유 방충다층필름의 경우 대조군 대비 약 90%의 억제율을 나타내 실험군들 중 가장 우수한 결과 값을 나타냈다. 따라서 실제 현미저장 실험은

Ⅳ. 연구개발결과
방충물질 후보군으로 선정한 11가지 식물 정유 및 이들을 구성하는 단일성분 중 대상해충에 대해 우수한 방충력을 보인 상위 4가지 물질은 마늘 정유, 양파 정유, 알릴 디설파이드, 알릴메르캅탄으로 확인되었다. 이들을 방충물질로 사용하여 제작한 방충다층필름은 방충물질 무처리 필름(대조군)에 비하여 매우 우수한 화랑곡나방 유충의 침투 억제율을 보였고 특히 5% 알릴 디설파이드 함유 방충다층필름의 경우 대조군 대비 약 90%의 억제율을 나타내 실험군들 중 가장 우수한 결과 값을 나타냈다. 따라서 실제 현미저장 실험은 5% 알릴 디설파이드 함유방충다층필름으로 진행되었으며 25℃ 인큐베이터에서 30일간 저장된 현미의 관능평가(sensory evaluation)를 실시하였다. 관능평가는 생현미와 조리된 현미를 시료로 하고, 시료의 향의 강도, 향·색·식감·맛의 기호도 및 전체적인 선호도를 평가항목으로 하여 50명의 비숙련 패널(panel)들을 대상으로 9점법(9-point intensity scale)을 이용하여 실행되었다. 그 결과, 생현미의 경우, 전체적인 선호도 항목에서 유의적인 차이를 보이며(p≤0.05) 대조군보다 낮은 점수를 나타냈다. 이는 현미 포장재로 사용된 5% 알릴 디설파이드 함유 방충다층필름의 알릴 디설파이드 성분이 현미에 이행 및 잔류되었고, 패널들이 이를 이취(off-flavor)로 판단하였음을 뜻한다. 그러나 조리된 현미의 전체적인 선호도의 경우, 대조군보다 낮기는 했으나 5점 이상으로 패널들의 평가가 긍정적이라고 간주할수 있었다. 이는 생현미의 관능평가 결과와 상이한데, 현미를 조리할 때의 수세(washing)·불리기(soaking)·익히기(cooking) 과정에서 현미에 이행 및 잔류된 알릴 디설파이드의 성분이 씻겨나가 제거되었기 때문인 것으로 판단된다. 현미는 날것 그대로 섭취하는 경우보다는 수세, 불리기 등의 과정을 거쳐 조리해 먹는 것이 일반적이므로 이러한 과정에서 현미에 이행된 방충물질이 거의 제거되어 미량만 남게 될 것이다. 따라서 방충다층필름의 향이 현미로 이행되는 것은 현미 취식 시 소비자들의 선호도에 미치는 영향이 적을 것으로 예상된다.
방충물질 후보군에 대한 쌀바구미 기피실험 결과, 가장 우수한 기피력을 나타낸 물질은 알릴 메르캅탄이었으므로 이를 중심물질로, 쌀가루를 벽물질3)로 이용하여 방충 미세캡슐을 제작한 뒤 사쉐(sachet)에 적재하여 쌀바구미 방제를 위한 방충향낭을 제작하였다. 가스 크로마토그래피(gas chromatography)를 이용하여 방충 미세캡슐의 방출경향을 분석한 결과, 방충물질인 알릴 메르캅탄이 720시간(30일)의 측정기간 동안 서방성을 보이며 서서히 방출되었음으로 곡류 포장재로의 응용에 적합함을 확인하였다. 또한 알릴 메르캅탄의 항산화 활성 실험 결과, 1 g 당 아스코르브산(ascorbic acid) 403.35 mg과 트롤록스(trolox) 1245.90 mg에 상응하는 항산화 활성을 나타냈으므로 ‘쌀바구미의 제어’라는 주요 효과 외에도 ‘곡류의 산패 억제’라는 부수적인 효과도 얻을 수 있을 것으로 예상하였다. 따라서 알릴 메르캅탄 방충향낭을 현미 포장재에 적용하여 이를 35℃의 인큐베이터에 4주간 저장하며 1주일 간격으로 현미의 산패도(산가와 과산화물가)를 측정하였다. 그러나 알릴 메르캅탄 방충향낭은 현미의 산패를 억제하는데 별다른 효과가 없는 것으로 확인되었다.

Abstract ▼

The stored product insects cause both quantitative and qualitative damages on processed food such as cookies, chocolate and instant noodle as well as cereal products. However, proposal of solution to solve these problems is not properly made out. Commonly, synthetic chemicals composed of methyl brom

The stored product insects cause both quantitative and qualitative damages on processed food such as cookies, chocolate and instant noodle as well as cereal products. However, proposal of solution to solve these problems is not properly made out. Commonly, synthetic chemicals composed of methyl bromide are widely used to control pests. However, methyl bromide, which is known as a carcinogenic substance, can be migrated and remained in food when it is used for anti-insect materials for food packaging. Therefore, eco-friendly and safe anti-insect material is required to be investigated. In this study, we developed the diverse anti-insect food packaging techniques using natural-derived plant essential oils which have effective insecticidal properties.
The first purpose of this study was to select test object insects and candidates of anti-insect materials from plant essential oils to control the stored product insects. Rice weevil (Sitophilus oryzae) and Indian meal moth (Plodia interpunctella) were selected as test object insects, and essential oil from garlic (Allium sativum), ginger (Zingiber officinalis), black pepper (Piper nigrum), onion (Allium cepa), cinnamon (Cinnamonum zeylanicum) fennel (Foeniculum vulgare) and, major single compounds (allyl disulfide and allyl mercaptan) of garlic and onion oil were selected as candidates of anti-insect materials. The anti-insect activities of those candidates against rice weevil and Indian meal moth were measured by fumigation assay, acetylcholinesterase inhibition assay and repellent assay.
In anti-insect activities experiments, garlic oil, onion oil, allyl disulifde and allyl mercaptan showed excellent results. Accordingly, anti-insect multi-layered films were made with these 4 substances by coating on low density polyethylene (LDPE) base film. The penetration test was performed to verify anti-insect ability of developed anti-insect multi-layered films and mechanical properties experiment was also carried out. All developed films presented excellent ability to inhibit penetration of Indian meal moth larvae compared with control(anti-insect material untreated film). Furthermore, 5% allyl disulfide containing films (AD 5) showed much superior ability than the other films. Hence, AD 5 was applied to brown rice packaging and sensory evaluation was performed to defined whether or not the AD 5 negatively affected odor migration when brown rice was packaged with AD 5.
To find out industrialization possibility of developed anti-insect multi-layered films, we manufactured the experimental products of AD 5 using an industrial facility (gravure printing machine).
Anti-insect sachet was also developed using allyl mercaptan which presented the best repellent activity against the rice weevils. To investigate the effect of developed anti-insect sachet on stored brown rice, the sachet inserted inside the brown rice packaging and the rancidity of brown rice was measured under storage.
Garlic oil, onion oil, allyl disulfide and allyl mercaptan showed the best anti-insect properties among the candidates of anti-insect materials. Anti-insect multi-layered films with anti-insect materials showed the excellent ability to inhibit the penetration of Indian meal moth larvae than films without anti-insect materials (control). Especially, fils with 5% allyl disulfide (AD 5) showed much superior ability than the other films. Therefore, AD 5 was applied brown rice packaging and stored in an incubator maintained at 25℃ for 30 days. The sensory evaluation was performed to confirm whether the odor of brown rice can be affected by the AD 5 migration or not, when brown rice was packaged with AD 5. In sensory evaluation of raw brown rice, the odor intensity of brown rice packaged by AD 5 was significantly different (p≤0.05), meaning that the brown rice was affected by AD 5 migration. Consequently, odor and overall preference which may be affected by odor migration were observed significantly decreased compared with control, whereas there was no significant difference (p>0.05) in the preference of color which did not be affected by odor. Moreover, the score of odor and overall preferences in AD 5 were lower than 5 point, which indicated that panels regarded the AD as an off flavor. On the other hand, in sensory evaluation of cooked brown rice, the intensity of odor was not significantly different (p>0.05) between samples packaged with AD 5 and control. This result is different from raw brown rice’s sensory result, because it was attributed to 3 cooking processes, including washing, soaking, and boiling which could remove the rest odor components. Even though odor, texture, taste and overall preference are significantly different between samples packaged with AD 5 and control, the score of all preferences were higher than 5 point, meaning that panels had a positive opinion about odor, color, texture, taste and overall aspects.
Allyl mercaptan showed the best repellent power against the rice weevils. When anti-insect microcapsule was made, allyl mercaptan was used as core material and rice flour as wall material. Prepared microcapsule was packed up into the sachet which can control rice weevils. The release tendency of microcapsule in sachet was analyzed by gas chromatography (GC). In result, microcapsule showed the sustained release property during measuring period (30 days). And this property indicates that allyl mercaptan sachet was suitable for packaging materials of cereal products. Also, allyl mercaptan showed the antioxidant activity equivalent to 403.35 mg of ascorbic acid and 1,245.90 mg of trolox. From these results, we expected ‘rancidity inhibition effect’ in addition to ‘rice weevil control’. Therefore, the sachet inserted inside the brown rice packaging and stored in an incubator at 35℃. And the rancidity (acid value and peroxide value) of brown rice was measured weekly for 4 weeks. But allyl mercaptan sachet had no antioxidant effect on deterioration of brown rice.
In this study, anti-insect packaging of cereal products has been developed using an essential oil having a great anti-insect ability and its single major component. Devices for measuring the repellent activity (patent application 10-2013-0111797 and registration 10-1566080) and measuring the penetration activity of vermin (patent application 10-2014-0156887), which were designed during this study, and a method for measuring the anti-insect ability can be standardized with a numerical value and can provide a intuitive value of experimental results. Hence, it can be expected that the devices and method can give a great contributions to further study. The anti-insect multi-layered films and anti-insect sachet, as a core result of this study, will be applied and registered for a patent and they can be exposed to the company, which hopes to utilize the anti-insect multi-layered films and anti-insect sachet in the industry. Also these novel packaging developed in this study can be commercialized and industrialized through this utilization and their manufactural method has a plan to be devised and redesigned considering the real industry. Therefore, industrialized anti-insect packaging can contribute to reduce quantitative and qualitative loss in food industry and contributes greatly to economy.