• 한국축산식품학회지
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• 제32권4호
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• pp.448-457
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• 2012

The predictive ability for off-flavor development and quality change of ground beef was evaluated using a microbial time temperature indicator (TTI). Quality indices such as off-flavor detection (OFD) time, color, pH, volatile basic nitrogen (VBN), aerobic mesophilic bacteria (AMB) counts, and lactic acid bacteria (LAB) counts were measured during storage at 5, 10, 15, and $25^{\circ}C$, respectively. Arrhenius activation energies (Ea) were estimated for temperature dependence. The Ea values for TTI response (changes in titratable acidity (TA)), VBN, AMB counts, LAB counts, and freshness, which is defined based on OFD time for quality indices of ground beef, were 106.22 kJ/mol, 58.98 kJ/mol, 110.35 kJ/mol, 116.65 kJ/mol, and 92.73 kJ/mol, respectively. The Ea of microbial TTI was found to be closer to those of the AMB counts, LAB counts, and freshness. Therefore, AMB counts, LAB counts, and freshness could be predicted accurately by the microbial TTI response due to their Ea similarity. The microbial TTI exhibited consistent relationships between its TA change and corresponding quality indices, such as AMB counts, LAB counts, and freshness, regardless of storage temperature. Conclusively, the results established that the developed microbial TTI can be used in intelligent packaging technology for representing some selected quality indices of ground beef.

• 한국포장학회지
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• 제27권2호
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• pp.55-62
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• 2021

This study aims to reduce the rancid odor generated during the fermentation process of kimchi by inserting zinc oxide (ZnO) into an inorganic porous material with a high surface area to decompose or adsorb the fermentation odor. ZnO activated by the presence of moisture exhibits decomposition of rancid odors. Mixed with Titanium dioxide (TiO₂), a photocatalyst. To manufacture the packaging liner used in this study, NaOH, ZnCl₂, and TiO₂ powder were placed in a tank with diatomite and water. The sludge obtained via a hydrothermal ultrasonication synthesis was sintered in an oven. After being pin-milled and melt-blended, the powders were mixed with linear low-density polyethylene (L-LDPE) to make a masterbatch (M/B), which was further used to manufacture liners. A gas detector (GasTiger 2000) was used to investigate the total amount of sulfur compounds during fermentation and determine the reduction rate of the odor-causing compounds. The packaging liner cross-section and surface were investigated using a scanning electron microscope-energy dispersive X-ray spectrometer (SEM-EDS) to observe the adsorption of sulfur compounds. A variety of sulfur compounds associated with the perceived unpleasant odor of kimchi were analyzed using gas chromatography-mass spectrometry (GC-MS). For the analyses, kimchi was homogenized at room temperature and divided into several sample dishes. The performance of the liner was evaluated by comparing the total area of the GC-MS signals of major off-flavor sulfur compounds during the five days of fermentation at 20℃. As a result, Nano-grade inorganic compound liners reduced the sulfur content by 67 % on average, compared to ordinary polyethylene (PE) foam liners. Afterwards SEM-EDS was used to analyze the sulfur content adsorbed by the liners. The findings of this study strongly suggest that decomposition and adsorption of the odor-generating compounds occur more effectively in the newly-developed inorganic nanocomposite liners.

• 한국식품영양학회지
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• 제23권2호
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• pp.218-225
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• 2010

본 연구에서는 기능성 식품 소재로서 이용가치가 높은 표고버섯 분말을 스폰지 케이크 제조에 이용하기 위하여 표고버섯 분말을 3, 6, 9, 12%로 첨가한 스폰지 케이크를 제조하여 품질 특성을 파악하고 최적 제품을 생산하고자 하였다. 표고버섯 분말을 첨가한 스폰지 케이크 반죽의 점도, 비중, 수분 함량은 대조군과 표고버섯 분말 첨가군 들 간에는 유의적인 차이를 나타내지 않았다. 표고버섯 분말을 첨가한 스폰지 케이크의 부피 지수는 대조군이 13.75로 가장 낮은 값을 나타냈으며, 표고버섯 분말 3~6% 첨가군에서는 높은 값으로 증가하다가 9~12% 첨가군에서는 감소하는 경향을 보였으나, 표고버섯 분말 첨가군이 대조군보다는 높은 값을 나타내었다. 무게는 대조군과 12%첨가군이 유사한 값을 보였으며, 표고버섯 분말 3% 첨가군에서 가장 높은 값을 나타내었다. Crust 색도 L, a, b는 모두 대조군에 비해 표고버섯 분말 첨가군에서 값이 낮게 나타났고, Crumb 색도 L은 대조군에서 가장 높은 값을 나타내었으며, 표고버섯 분말 첨가량이 증가할수록 낮은 값을 나타내었다. a는 대조군이 가장 높은 값을 나타냈으며, 표고버섯 분말 첨가량이 증가할수록 낮은 값을 나타내었다. b는 대조군과 3% 첨가군간에 유의적인 차이가 있었으며, 6~12% 첨가군 간에는 유의적인 차이가 없었다. 표고버섯 분말을 첨가한 스폰지 케이크의 견고성(hardness)은 대조군과 표고버섯 분말 3% 첨가군에서는 차이가 없었으나, 6% 이상 첨가군에서는 대조군보다 낮은 값을 나타내었다. 파쇄성(fracturability)은 대조군과 표고버섯 분말 3% 첨가군 간에는 유의적인 차이가 없었으나 6% 이상 첨가군에서는 대조군보다 낮은 값을 나타내었다. 부착성(adhesiveness)은 대조군과 표고버섯 분말 첨가군들이 유사한 값을 나타냈으며, 씹힘성(chewiness)은 표고버섯 분말 3% 첨가군에서 가장 높은 값을 나타냈다. 복원성(resilience)은 대조군이 가장 낮은 값을 나타냈으며, 표고버섯 분말 첨가군에서는 유의적인 차이를 나타내었다. 관능검사의 색(color), 향미(flavor), 부드러운 정도(softness), 전체적인 기호도(overall acceptability)는 대조군이 가장 높은 값을 나타내었고, 표고버섯 분말 첨가량이 증가할수록 낮은 값을 나타내었다. 표고버섯 향(Lentinus edodesflavor), 구수한 맛(pleasant taste), 부적합한 향미(off-flavor)는 대조군이 가장 낮은 값을 나타내었고, 표고버섯 분말 첨가량이 증가할수록 증가하는 경향을 보였다. 계란향(egg-flavor), 촉촉함(moistness)은 대조군이 가장 높은 값을 나타내었고, 표고버섯 분말 첨가량이 증가할수록 감소하는 경향을 보였다. 이상의 결과를 종합해 보면 대조군이 기호도 검사에서 가장 높은 점수를 나타내었고, 표고버섯 분말 첨가량이 증가할수록 낮은 점수를 나타내긴 하였지만, 전체적인 품질 특성의 결과를 고려할 때 표고버섯 분말의 3% 첨가가 최적의 배합비로 사료된다.

• Journal of Dairy Science and Biotechnology
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• 제16권2호
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• pp.90-97
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• 1998

본 실험은 저온장시간(LTLT), 고온단시간 (HTST) 그리고 초고온순간(UHT) 열처리한 시유를 사용하여 저장기간에 따른 시유의 미생물수와 이취의 변화를 조사함으로써 살균방법이 품질에 미치는 영향을 조사하였다. 시유의 생산일로부터 1일째를 저장 0일로 하여 0, 5, 9, 12, 15일까지 10$^{\circ}C$에서 저장한 시료의 미생물수를 측정한 결과, LTLT 처리유 경우 총 미생물수는 저장0일째에 5.0${\times}$10$^3$ cfu /ml에서 저장 5일째 2.4${\times}$10$^6$ cfu /ml로 급격한 증가를 보였으며 저장 15일까지 계속적인 증가를 보여 2.3${\times}$10$^9$ cfu /ml에 달하였다. 내냉성 미생물은 3.3${\times}$10$^3$ cfu /ml (저장 0일째) 에서 1.2${\times}$10$^6$ cfu /ml (저장 5일째)로 총 균수와 거의 유사한 경향을 보였다. HTST 처리유의 경우 10$^{\circ}C$에서 총균수는 저장초기 5.0${\times}$10$^3$ cfu /ml (0일)에서 4.6${\times}$10$^9$ cfu /ml 으로 증가하였다. 내냉성 미생물 또한 급격한 증가 추세를 보였다. 대장균과 병원성 균수는 LTLT와 HTST 처리유 모두에서 저장 12일 이후에 나타나기 시작하였다. UHT 처리시유의 경우는 저장 15일째에 적은 수의 미생물만이 검출되었다. 위 실험의 결과, 원유를 LTLT와 HTST로 처리한 시유는 저장 중 함유된 미생물의 증가를 보였으며, 10$^{\circ}C$ 저장시 5일째부터 보사부규정인 일반세균 2.0${\times}$10$^4$ cfu /ml 을 상회하는 수치를 나타내어 원유의 질에 있어서 시유에 내재하는 미생물이 중요함을 시사하였다. 저장기간에 따른 이취의 변화는 LTILT와 HTST 처리유에서는 12일째부터 유의적 차이를 보이기 시작한 반면, UHT 처리유의 경우에는 9일째에 이취의 발생이 급속히 증가하는 것을 나타내었다. 따라서 본 실험의 결과를 토대로 미생물학적인 면으로는 UHT 처리유의 품질이 저장 9일까지 큰 변화가 없으나, 관능적인 면으로는 이취의 발생으로 인한 품질 저하가 유발된다고 사료된다. 그러나 LTLT와 HTST 처리유의 경우는 반대의 양상을 보였다. 따라서 미생물적인 면과 괸능적면 모두를 감안한다면 현재의 유통기간 5일이 LTLT나 HTST 처리유에게는 적합한 것으로, UHT 처리유에게는 5일 이상도 가능하리라 사료된다.

• 원예과학기술지
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• 제28권6호
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• pp.980-984
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• 2010

깻잎을 active MA 소포장 후 실온(약 $27^{\circ}C$)에서 호흡, 이취 관련 물질 및 신선도 유지효과에 관한 연구결과는 다음과 같다. 저장기간 중 호흡율은 무처리 및 저산소 처리구($CO_2:O_2:N_2$=6:2:92, 0:10:90) 보다 고산소 처리구(0:30:70 및 0:50:50)에서 높게 유지되었고, 에틸렌 발생도 다소 높았다. 그러나 이취관련 물질인 아세트알데히드 및 에탄올 발생은 고산소 처리구에서 현저하게 낮았다. 중량감소율은 무처리 및 저산소 처리구에서 약 1.8%, 고산소 처리구에서는 1.4%로 낮았지만, 저장 5일째는 유사한 경향을 나타냈다. Ascorbic acid 함량은 저장 1일에 13.3mg/100g F.W.이었고, 저장 3일에 무처리구에서 8.8mg/100g F.W.으로 가장 낮았으나, active MA 처리구에서는 커다란 차이 없이 저장기간이 길어짐에 따라 다소 감소하는 경향을 보였다. 엽록소 함량은 저장 5일째는 무처리구에서 47.5(SPAD-502 unit)로 가장 낮았고, active MA 처리구에서는 약 53.0 수준으로 높게 유지되었다. 관능 평가(시각)에서 저장기간 동안 서서히 감소되어 고산소 처리구(0:30:70 및 0:50:50)에서 저장 5일에 2.8로 상품성을 유지하였지만, 무처리 및 저산소 처리구에서는 상품성을 상실하였다. 이취발생은 저장 5일에 무처리구에서는 2.6으로 매우 낮았고, 고산소 처리구에서는 3.4 수준으로 높았다. 따라서 깻잎을 active MA 포장할 경우 실온에서(약 $27^{\circ}C$) 일반 MA포장 보다는 2일정도 더 신선도 유지효과가 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권2호
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• pp.267-276
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• 2005

This study was carried out to investigate the effect of phytosterol ester addition on lowering blood cholesterol in cholesterol-reduced Cheddar cheese. For cholesterol removal, separated cream was treated with 10% ${\beta}$-cyclodextrin at 800 rpm, then blended with remaining skim milk and homogenized with 1,000 psi at $70^{\circ}C$. Experimental cheeses were manufactured by five different levels of phytosterol addition. After the cholesterol reduction process by ;${\beta}$-cyclodextrin, the cholesterol removal rate was in the range of 91.0 to 92.1%. Amount of short-chain free fatty acid and free amino acids increased with an increase of phytosterol ester, and those were significantly different from that of control in all ripening periods. All rheological properties also increased with an increase of phytosterol ester during ripening period. In sensory analysis, the scores of rancid, bitterness Cheddar flavor and off-flavor intensities increased significantly, while texture was decreased during ripening in phytosterol ester-added groups. Total blood cholesterol was reduced by 18% when rats were fed Cheddar cheese treated with 8% phytosterol. The present study indicated that phytosterol ester addition resulted in a profound lowering effect of blood with cholesterol-reduced Cheddar cheese.

• Food Science and Biotechnology
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• 제17권3호
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• pp.534-539
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• 2008

This study investigated the effects of pretreatment and storage conditions on the properties of stored chestnuts. Effects on chestnuts of refrigerated storage (RNT) and frozen storage (FNT) with no pretreatment, frozen storage after oxalic acid treatment without blanching (FON) and with blanching (FOB) were examined. Water binding capacity, swelling power, solubility, and viscosity of the starch produced from RNT, FNT, and FON were similar to those of the starch produced from control (CON). FOB showed significant differences in these properties from CON. Textural properties of starch gels prepared from stored chestnuts except FOB also were very similar to those of CON starch gels. The sensory characteristics of steamed FON and FNT were similar to those of steamed CON except in brown color and hardness. Steamed FNT tended to have higher brown color and lower hardness than steamed FON. Steamed RNT showed significant differences in all the sensory properties except in hardness and cooked chestnut flavor. Steamed FOB was significantly higher than steamed CON in water release and off-flavor. Among the storage conditions examined, frozen storage with oxalic acid treatment is recommended for the long-term storage of chestnuts.

• 한국식품조리과학회지
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• 제26권5호
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• pp.537-544
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• 2010

This study was conducted to find an efficient use for mulberry fruit powder (MFP). MFP was added to salad dressing products at concentrations of 0.25, 0.5, 0.75, 1%, and pH, total acidity, viscosity, color, and emulsion stability were measured and sensory evaluation was conducted. There were no significant differences among salad dressing samples regarding pH, total acidity and moisture content. Salad dressing made with 0.5% MFP showed significantly higher viscosity during storage and made the most stable emulsion. For color, the control sample had the highest L and b values, and these values decreased significantly as the amount of MFP in the sample increased. The control salad dressing had the lowest a value of -3.26, and this value increased significantly as the amount of MFP in the sample increased. Sensory evaluation of salad dressing was performed by a trained consumer panel. The flavor intensity increased as the amount of MFP increased in the salad dressing samples. Sweetness was rated significantly higher as the amount of MFP increased in the samples. The control sample had the lowest sourness and off-flavor, but there was no significant difference compared to the samples containing MFP.

• 한국가금학회지
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• 제26권1호
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• pp.1-25
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• 1999

Concerns about meat quality, including chicken meat, for the human diet has led to many attempts to manipulate the carcass fat and increase the eating quality. For actual eating quality, the birds must be grown and finished in a manner that results in meat that are tender, succulent and of good flavor, as well as being free from any foreign taint, flavor or safety hazard. Tenderization treatment with high voltage(820V) electrical stimulation and prechill muscle tensioning would improve the tenderness of chicken meat. Proper programs for the withdrawal of feed and water require a team approach for maximizing yield of meat and minimizing carcass contamination. Also effding of supplemental levels of-tocopherol to poultry with vegetable or fish oils increases of desirable polyunsaturated fatty acid(PUFA) content and stablizes the meat against rancidity and fish off-flavors. The nutritional effects of varying dietary ingredients on broiler carcass fat content are also important. Increasing the levels of energy in the ration increases the carcass fat content, while increasing the proteing levels decreases carcass fat content. Supplement-tation of poultry diets with amino acids such as methionine, lysine, glycine and tryptophan as well as amino acid such as well as amino acid mixtures can reduce body fat deposition. Normal stress leads to chicken muscular damage resulting in reduced meat quality, but this can be controlled by preslaughter management practices. Feed manufactures can utilize ntilize nutrient modulation to control pale soft exudative(PSE)syndrome. Finally, the success in poultry meat production depends on the consistent achievement of carefully selected levels of quality. Quality assurance should be the wider function of incorporating quality into the production system and the combination of motivating quality into actions and operations.

• 한국식품영양학회지
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• 제6권1호
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• pp.1-7
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• 1993

19 Samples of koji-starters using in brewing were collected from Korea and Japan, and then 31 strains of koji-molds were isolated from them. After Identification of the Isolate, rice koji was made with each strains, and its saccharogenic activity, dextrogenic activity, proteolytic activity, acid Producing ability, browning reaction and flavor were tested. Among 31 strains of isolates, 10 strains were Identified as Asp nwamori var. kawachii, 18 strains as Asp. oryzae, 3 strains as Asp. usamii mkt. shirousamii. The koji-starters made in Korea were composed of single species of koji-mold with same strain, but those made in Japan were composed of the mixture of different two species or the mixture of different 2 ∼4 strains in same species. Judging from amylolytic and proteolytic ability by species, Asp. awamori var. kawachii H1, I1 and 11, Asp. owsae J2, L2, M2, P3 and P4, and Asp. usamii writ. shirousamii S1 were better than the others. Mold strains isolated from Korean koji-starters were much lower in amylolytic or proteolytic activity than those from Japanese koji-starters. The typical characteristics for the 3 species of koji-molds were that Asp. awamori var. kawachii was strong in acid producing ability, but week in amylolytic and proteolytic ability, that Asp. owzae had strong amylolytic activity and good aroma, but produced little amount of acid, and that Asp. usamii mut. shirousamii had strong Proteolytic activity but some off-flavor.