• Agricultural and Biosystems Engineering
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• 제1권1호
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• pp.38-42
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• 2000

Though the freshness for agricultural products is an important factor related to their quality management, this terminology is being used restrictedly because it is very subjective. In this study, a dimensionless index which had the span of the maximum of 1 through the minimum of 0 was proposed to describe freshness of the product with time-variant quality and was applied to Tsugaru and Fuji apples. First, the compressive properties having the linearity in their change regarding time elapsed after harvest were selected. For Tsugaru apple, bio-yield and rupture forces had high correlation with time while for Fuji, bio-yield and rupture deformations had high correlations. When the slope, or ratio of force to deformation, was considered, the effect of cultivar could be neglected. When the linearly time-variant compressive properties for Tsugaru and Fuji apples were involved in the freshness indices, they described well freshness of apples. Also, the freshness decay constant depicted a characteristic which related to freshness decay rate. Therefore, the freshness index can be utilized to manage the quality during storage and distribution of apples.

• 정보보호학회논문지
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• 제18권6B호
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• pp.219-232
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• 2008

A novel idea of protocol security analysis is presented based on trusted freshness. The idea has been implemented not only by hand but also by a belief muitisets formalism for automation. The key of the security analysis based on trusted freshness is a freshness principle: for each participant of a cryptographic protocol, the security of the protocol depends only on the sent or received one-way transformation of a message, which includes a trusted freshness. The manual security analysis method and the belief multisets formalism are all established on the basis of the freshness principle. Security analysis based on trusted freshness can efficiently distinguish whether a message is fresh or not, and the analysis results suggest the correctness of a protocol convincingly or the way to construct attacks intuitively from the absence of security properties. Furthermore, the security analysis based on trusted freshness is independent of the idealization of a protocol, the concrete formalization of attackers' possible behaviors, and the formalization of concurrent runs of protocols.

• Journal of Biosystems Engineering
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• 제22권4호
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• pp.433-438
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• 1997

The freshness of apple was evaluated by characterizing the surface texture of flesh cells. The freshness index which was related to the amount of wrinkles on the cell surface was defined to quantify the freshness. Four parameters relevant to the amount of the cell wrinkles were selected and measured using image analysis including wrinkle extraction procedure and Fast Fourier Transform of a wrinkle-extracted image. Out of 4 parameters, three parameters had highly significant correlations with the time elapsed after harvest. But it was concluded that two parameters out of such 3 parameters could be used for description of freshness index.

• Applied Biological Chemistry
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• 제49권2호
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• pp.158-162
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• 2006

두부의 저장 중 신선도를 판정 할 수 있는 신선도표시계를 제작하여 두부의 표면에 부착하여 품질변화를 측정하였다. 부패시점을 판정하기 위하여 pH, VBN, TBARS, 총균수 및 관능검사를 수행하였다. 두부의 저장 중 품질변화를 측정한 결과 신선도표시계의 반응 시점과 같은 저장 8일째에 두부는 부패초기수준에 도달하여 pH는 5.6, 총균수는 7.63 log CFU/g의 값을 나타내었다. 또한 VBN, TBARS 값도 상승하였고, 관능검사 결과도 저장 8일 이후에는 이취 및 표면에 점질물 생성 및 조직의 저하 등 가식이 불가능 하였다. 따라서 본 연구에서 사용된 신선도표시계는 두부의 저장 중 신선도를 실시간으로 나타내줌으로써 두부의 유통기한 확립 측면에서 매우 유용한 도구가 될 것으로 판단된다.

• 수산해양교육연구
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• 제27권4호
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• pp.1194-1201
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• 2015

This study conducted to investigate the impact of raw material freshness on the quality and hygienic safety of anchovy fish sauce and suggest the importance of raw material freshness to make high-quality and hygienic anchovy fish sauce by measuring the chemical compositions and histamine. To devide the raw material's freshness levels, raw anchovy was left for 24 hours and was sampled every 4 hour(Group I-VII). As a result, the levels of VBN(volatile basic nitrogen) and histamine increased as time passed each contents were 16.29-87.65 mg/100 g and 6.14-1499.63 mg/100 g respectively. As fish sauce fermented for 18 months, the contents of VBN were 205.31-270.51 mg/100 g and histamine were 120.54-1707.22 mg/100 g, respectively. These results means the levels of VBN and histamine of raw materials are significantly associated with the hygiene of anchovy fish sauce. To investigate the reason of different contents of histamine at each fish sauce, bacteria from each groups were isolated and identified. At group V-VII those the lowest three groups, Leconostoc mesenteroides ssp. cremoris was identified and that produced the highest content of histamine 22.88-101.69 mg/kg and the others produced histamine 3.79-20.2 mg/kg. This means that fish sauce made by low freshness materials contain bacteria have strong ability to make histamine from histidine. Therefore, the freshness of raw material influences the hygiene and safety of fish sauce, and it is most important to manage the freshness of raw material to make the high quality and hygienically safe fish sauce.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2007년도 춘계종합학술대회
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• pp.449-451
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• 2007

텅스텐-할로겐(300 - 1050 nm) 광원을 사용한 광학적 방법으로 계란의 신선도를 측정하였다. 계란의 신선도는 저장온도, 습도, 이산화탄소 농도, 저장 기간 및 유전 형질에 따라 달라진다 광원을 조사하여 투과 및 반사 스펙트럼을 분석하여 계란의 신선도를 파악하였다.

• Journal of Biosystems Engineering
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• 제29권6호
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• pp.539-543
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• 2004

The purpose of this study was to develop a real-time sensor for beef freshness. Contents of biogenic amines (BA), saccharides and proteins were highly related with freshness on the beef meats. Relations of those chemical contents and NIR spectra were studied. Tyramine showed the best correlation coefficient at 1250nm. Correlation between VBN (volatile basic nitrogen) and K value, which were both freshness measurement method, was determined by the PCR (principle component regression). The correlation model had the values of $R^2=0.989$ and SEC=1.78, respectively. The model was validated at $R^2=0.963$ and SEP=2.285, respectively.

• 한국수산과학회지
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• 제55권5호
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• pp.670-680
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• 2022

Owing to the lack of a cold-chain distribution system, most seafood is generally distributed under room temperature conditions. However the degradation of freshness during the distribution process can lead to disputes between sellers and consumers. The most widely used method for low-temperature distribution for seafood includes packaging it with styrofoam boxes and cold packs. In this study, vacuum-packed frozen fillets of four fish species of [white meat (Paralichthys olivaceus and Sebastes schlegelii) and red meat (Scomber japonicus and Scomberomorus niphonius)] were placed in styrofoam boxes with cold packs. Thereafter, changes in chemical (including pH, volatile basic nitrogen, and trimethylamine), physical (odor intensity, hardness, and chewiness), and microbial (viable cell count) characteristics of the fillets were measured during storage at 25℃. To identify the suitable method of determining freshness during the room-temperature distribution, several factors were considered, which included significant difference verification, correlation coefficients, and economic efficiency (experimental cost and time). Volatile basic nitrogen, pH, odor intensity, and viable cell count are the most rapid and accurate freshness indicators for determining freshness of frozen fish fillets during.

• 한국유기농업학회지
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• 제30권2호
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• pp.291-302
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• 2022

Food safety is a fundamental requirement for consumers. Therefore, this study was aimed to determine the freshness of pork fillets based on freshness index (Ki value) analysis during storage. This study obtained a total of 24 pork fillets. This study was divided into 4℃ and -20℃ temperatures. Again, each temperature was divided into 4 different groups based on storage durations (15d). Each group was obtained in triplicate. The level of malondialdehyde (MDA) value was significantly increased at 4℃ than the -20℃ storage with the duration of storage days. The levels of inosine-5'-phosphate (IMP) in pork fillets were significantly decreased at 4℃ and -20℃. Hypoxanthine (Hx) levels were significantly increased at 15 days than those at 0 days during storage at both temperatures (4℃ and -20℃). Subsequent freezing increased more inosine levels at -20℃ than storage at 4℃. The Ki values were increased during storage days at both temperatures, although after 15d storage, its values at 4℃ were significantly higher than those at -20℃. These results demonstrated that storage period and temperature might affect the freshness of pork fillets via lipid oxidation and nucleotide degradation. This study suggested that the Ki value will be the crucial indicator of measurement of freshness of stored pork fillets.

• 수산해양교육연구
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• 제20권1호
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• pp.127-134
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• 2008

The purpose of this study was to determine content of biogenic amines (Histamine, Cadaverine, Putrescine) in the salted mackerel, canned mackerel, mackerel pike, and freeze dried mackerel pike (Guamegi) collectively, all were purchased in the market. Salted mackerel was purchased at five markets (A, B, C, D, and F market) and stored for 10 days at $4{^{\circ}C}$. At the time of purchase, salted mackerel purchased at markets A, B and C was tested for biogenic amine, yet nothing was detected. However, salt mackerel purchased at market D was tested and the histamine concentration was 0.5 mg/100g. Mackerel from market F, exhibited content levels of 0.5 mg/100g histamine and 1.6 mg/100g cadaverine. Those make certain safety during self-life but that purchased F market gradually increased biogenic amine during storage. Prepared salted mackerel of varying levels of freshness and processing methods were analyzed for biogenic amines. Salting process was performed using functional brine salt. VBN (volatile basic nitrogen) was used to establish freshness levels of salted mackerel. Analyses of mackerel muscle determined the values of freshness to be 9.2 mg/100g (good freshness), 18.2 mg/100g (bad freshness), respectively. After 40 days of storage, the content of histamine, cadaverine, putrescine in the freshness of salted mackerel was 2.0 mg/kg, 2.4 mg/kg and 0 mg/kg, respectively. The content of histamine, cadaverine, putrescine in salted mackerel of poor freshness was 71.3 mg/kg, 22.9 mg/kg and 17.8 mg/kg, respectively. It was concluded the presence of biogenic amines during the salting process of salted mackerel significantly effected freshness of materials. The presence of biogenic amines were detected in mackerel that underwent the salting process after 1 month of storage at $4{^{\circ}C}$. The levels of biogenic amines in the brine salted mackerel were higher than those found in dry, salted mackerel; however, the freshness of fish had an insignificant effect on biogenic amines. The presence of histamine was detected in small quantities in canned mackerel and mackerel pike from three companies. Alternatively, cadaverine and putrescine were not detected. Guamegi, vacuumed packed or sealed with a rope was purchased from three markets (A, B, C seafood company). Guamegi was stored and observed for 180 days at $-20{^{\circ}C}$. Histamine was detected in small quantities in all products stored at $-20{^{\circ}C}$. Levels of histamine was dependent on the types of packaging, rope packaging yielded the highest level. However, other amines were not detected.