• Journal of Biosystems Engineering
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• 제24권5호
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• pp.407-414
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• 1999

To evaluate the quality of flame-peeled chestnuts, their physical and chemical properties were analyzed. The physicochemical properties of flame-peeled chestnuts, including geometrical shape, texture and chemical composition, were compared to those of hand-peeled ones. For the flame-peeled chestnuts, some properties in heated and non-heated sections were separately analyzed. The color, texture such as springness, cohesiveness, adhesiveness, hardness and chewiness, moisture content, and reducing sugar of the heated section of the flame-peeled chestnuts were significantly different with their non-heated section. But the physicochemical properties of the non-heated section of the flame-peeled chestnuts were similar to those of the hand-peeled ones.

• 한국포장학회지
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• 제7권1호
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• pp.25-30
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• 2001

The purpose of this study was to examine how can we keep the freshness of peeled chestnuts in distribution process. The 30 minutes impregnation treatment at the preservation solution of 0.3% consistency showed a good result. The solution treatment prevented from surface yellowing and quality degradation of peeled chestnuts. And, in vaccum packaging after treating chemicals surface drying was faster than the other packaging from 7th day. A vitamin C treatment was no effective to restrain the growth of microbials.

• Journal of Biosystems Engineering
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• 제33권1호
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• pp.21-29
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• 2008

In this study, the thermal properties of peeled chestnuts were measured, and the mathematical prediction model of freezing time was also developed for various interior positions from center to rind (surface). The measured thermal properties were showed that heat conductivity is $0.43W/m^{\circ}C$, specific heat is $2.7206J/m^3^{\circ}C$, latent heat is $216.9{\times}10^6J/m^3$ and freezing point is $-2.8^{\circ}C$. The entire process about reaching to the freezing time of peeled chestnuts was analyzed with its each regular depth position using the finite difference method (FDM) based on computer simulation. In case of regular freezing temperature, it was showed an that surface (rind) position is more rapidly reached into the freezing point rather than the center position, and also reaching time to the freezing point is more fast at the lower freezing temperature. Comparison results between simulation and experiments showed linear relationship. In regularly varying condition for freezing temperature, this method would give an information to predict a freezing time of the interior points for peeled chestnuts and more similar agricultural products.

• 한국식품영양학회지
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• 제24권1호
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• pp.71-78
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• 2011

Peeled chestnuts were stored at different temperatures($-10^{\circ}C$ and $-20^{\circ}C$) and for different times(0, 10, and 20 min at $90^{\circ}C$) for blanching over a 6 month period. Analyses were conducted for moisture content, total sugar content, browning index, polyphenol compounds, PPO activity, and SEM. Moisture content and PPO activity were increased by storage time. The increments for the samples stored at $-20^{\circ}C$ were lower that for the samples stored at $-10^{\circ}C$. The Browning index was increased by storage time, and increments for the samples stored at $-20^{\circ}C$ were lower that for the samples stored at $-10^{\circ}C$. Scanning electronic microscopy(SEM) studies were performed on peeled chestnuts. Results showed that the wrinkle structure of the cell wall was enhanced by storage time, and the level of enhancement was higher at $-10^{\circ}C$ than at $-20^{\circ}C$.

• 한국자원식물학회지
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• 제27권1호
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• pp.72-79
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• 2014

본 연구는 마찰과 칼날 박피방식과 저장온도에 따른 박피밤의 품질 변화를 조사하기 위하여 수행되었다. 박피밤의 중량감소율은 저장기간 동안 모든 처리구에서 관찰되었으며, 박피방식에 따른 차이는 관찰할 수 없었다. 그러나 박피밤의 수분함량은 모든 처리구에서 저장기간에 따라 감소하는 경향을 보였는데, 마찰박피밤이 모든 처리구에서 칼날박피밤 보다 수분함량이 높았다. 박피밤 색도의 경우 a, b, ${\Delta}E$값은 모든 처리구에서 저장기간 동안 증가한 반면, L값은 저장기간 동안 감소하였다. 다만, 마찰 박피밤의 갈변정도가 칼날 박피밤보다 높게 나타났다. 과육경도는 마찰박피와 칼날박피에서 $-1^{\circ}C$ 처리구의 밤이 가장 높았으며, 당함량은 저장직후부터 감소하였으나 저장 24일째부터 당함량이 증가하는 경향을 나타내었다. 박피밤의 식미와 식감은 모든 처리구에서 저장기간이 늘어날수록 감소하였으며, 저장 15일 이후로 급격하게 감소하는 경향을 보였다. 따라서 위의 결과를 볼 때 마찰과 칼날 밤피밤의 품질차이는 나타나지 않았다. 하지만 $4^{\circ}C$와 $2^{\circ}C$에서 저장한 박피밤은 15일 이후 품질이 급격하게 감소한 반면 $-1^{\circ}C$에서 저장한 박피밤은 천천히 감소하여 품질을 유지하는데 효과적이었다. 또한 마찰 박피밤의 갈변을 줄일 수 있으면 고품질의 우수한 박피밤이 생산될 수 있을 것이다.

• 한국식품영양학회지
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• 제22권4호
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• pp.587-597
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• 2009

Peeled chestnuts were stored at different temperatures($-10^{\circ}C$ and $-20^{\circ}C$) and after blanching at $90^{\circ}C$ for different lengths of time(0, 10, and 20 min) for 6 months. After the storage period, the texture, color, DSC and sensory characteristics were analyzed. Hardness, fracturability and chewiness increased with storage time, whereas springiness and cohesiveness decreased. Additionally, the L* decreased and a* and b* increased with storage time. Analysis of the DSC revealed that the peak of the retro gradation was approximately $46{\sim}60^{\circ}C$ and enthalpy for the peak increased with storage time. Additionally, the increment of enthalpy for samples stored at $-20^{\circ}C$ and blanched was lower than that of samples stored at $-10^{\circ}C$ and non-blanched samples. The sensory evaluation scores were also higher for samples stored at $-20^{\circ}C$ and blanched samples than for those stored at $10^{\circ}C$ and non-blanched samples.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1999년도 동계 학술대회 논문집
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• pp.509-515
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• 1999

• Applied Biological Chemistry
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• 제41권7호
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• pp.545-549
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• 1998

수출용 깐밤의 유통과정 중 발생하는 백탁현상을 방지하기 위하여 전해산화수를 이용하여 수출용 깐밤의 저장성을 향상시키는 연구를 있다. 수출용 깐밤을 전해수로 저장하면서 저장액의 pH및 탁도 변화를 조사 하였는데, $30^{\circ}C$에 저장했을 경우 저장 하루만에 이미 저장액의 pH가 급격히 변화하였으나, $4^{\circ}C$에 저장했을 경우는 $30^{\circ}C$에 비해 pH가 매우 완만하게 변화하였다. 특히 pH 2.5의 전해산화수는 저장 8일 후 pH가 3.4로 나타나 가장 적게 변화하였다. 탁도도 이와 비슷한 경향을 보였는데, $30^{\circ}C$에 저장했을 경우 저장 1일 후 이미 눈으로 확인할 수 있을 정도의 백탁현상이 일어났으나, $4^{\circ}C$에 저장했을 경우는 저장 14일 까지 백탁현상이 일어 나지 않았으며, 특히 pH 2.5의 전해산화수의경우 14일 후의 흡광도$(OD_{660})$가 0.01, 35일 후의 흡광도가 0.11로 나타나 백탁현상이 거의 일어나지 않았다. 전해수를 사용해 $4^{\circ}C$에서 15일간 저장한 깐밤에 대한 관능검사를 실시한 결과 대조구에 비해 유의한 차가 없었다.

• 한국산림과학회지
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• 제102권1호
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• pp.7-14
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• 2013

본 연구는 효율적인 박피 밤 생산을 위한 마찰식 박피기의 최적조건과 품종별 밤 과실의 내피박피성을 구명하고자 실시하였다. 마찰식 박피기의 최적조건은 박피시간 50분, 드럼 회전속도 27 rpm이었으며, 내피박피율도 89.3%로 가장 우수하였다. 최적의 박피조건(27 rpm/50분) 하에서 '축파' 등 8품종에 대한 내피박피율을 조사한 결과, '축파'가 89.3%로 가장 우수하였으며, '단택(72.2%)', '석추(70.9%)' 등의 순인 것으로 나타났다. I등급 밤의 비율은 '축파'가 77.2%로 가장 월등하였으며, '석추(46.7%)', '단택(45.0%)' 등의 순으로 높았다. 상품화 비율도 '축파'가 90.5%로 가장 우수하였으며, '단택(74.8%)', '석추(74.3%)' 등의 순으로 나타났다. 박피 시 과육 파손 및 흠집 발생 비율은 '미풍'이 37.2%로 가장 많은 반면, '축파'는 5.9%로 가장 적어 '축파' 품종이 마찰식 박피기를 활용한 고부가가치 가공 밤 생산을 위한 적합한 품종임을 알 수 있었다.

• Journal of Biosystems Engineering
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• 제38권3호
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• pp.185-191
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• 2013

Purpose: The present study focused on the estimation of soluble solids content (SSC) of chestnut using reflectance and transmittance spectra in range of VIS/NIR. Methods: Four species intact/peeled chestnuts were used for acquisition of spectral data. Transmittance and reflectance spectra were used to develop the best PLS model to estimate SSC of chestnut. Results: The model developed with the transmitted energy spectra of peeled chestnuts rather than intact chestnuts and with range of NIR rather than VIS performed better. The best $R^2$ and RMSEP of cross validation were represented as 0.54 and $1.85^{\circ}Brix$. The results presented that the reflectance spectra of peeled chestnuts by species showed the best performance to predict SSC of chestnut. $R^2$ and RMSEP were 0.55 and $1.67^{\circ}Brix$. Conclusions: All developed models showed RMSEP around $1.44{\sim}2.54^{\circ}Brix$, which is considered not enough to estimate SSC accurately. It was noted that $R^2$ of cross validation that we found were not high. For all that, grading of the fruits in two or three classes of SSC during postharvest handling seems possible with an inexpensive spectrophotometer. Furthermore, the development of estimation of SSC by each chestnut species could be considered in that SSC distribution is clustering in different range by species.