• Food Science and Biotechnology
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• 제15권3호
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• pp.374-379
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• 2006

This study was carried out to investigate the physicochemical properties of frozen pork muscle which has been thawed using the ohmic thawing process, and to establish the optimal ohmic power intensity. The samples were frozen at $-40^{\circ}C$ and thawed at 0, 10, 20, 30, and 40 V by ohmic thawing. Increasing ohmic power intensity correlated with increased thawing rates. The relationship between ohmic power intensity and thawing rate can be represented as a polynomial function. The pH value decreased with increasing ohmic power intensity (p<0.05). With regard to color measurement, the $L^*$, a, and b values of thawing at all ohmic power intensities were not significantly different. The water holding capacity showed a peak value of 41.62% with an ohmic thawing intensity of 30 V. Cooking losses were lowest at the lowest ohmic thawing intensity of 10 V. Thiobarbituric acid reactive substance (TBARS) levels with all thawing processes were slightly higher than that of the control (p<0.05). Increasing ohmic power intensity did not tend to change the total volatile basic nitrogen (TVBN) value.

• 한국수산과학회지
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• 제54권6호
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• pp.861-868
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• 2021

To confirm the influence of modified starch on frozen storage stability, the microstructure and sensory characteristics of fish cakes, called Eomuk in Korea, by using seven varieties of starch, including native starch (NS), physically treated corn starch (MS) and modified starch [treatment with acetate (SA-1, SA-2 and SA-3), hydroxypropyl (HS), and acetylated distarch adipate (ADA)] were evaluated. Scanning electron microscopy (SEM) photographs showed fish cakes with NS had a finer and denser network structure than those made with modified starches. During frozen storage, fish cakes with HS and ADA exhibited a stable structure, as evaluated by porosity and rough surface. The results of the sensory evaluation showed that modified starch, including HS, SA-2 and ADA, increased the taste and firmness of the fish cakes, while NS, MS and the modified starch SA-3 resulted a decrease in the sensory properties during storage. Therefore, HS, SA-2 and ADA are suitable additives to improve the sensory quality of frozen fish cakes.

• Preventive Nutrition and Food Science
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• 제1권2호
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• pp.252-255
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• 1996

As an index of freeze-injury of yeast, the leakage of intracellular substances from yeast cells after freeze-thawing was investigated. It was found that much more ultraviolet-absorbing substances leaked out from non-freeze tolerant yeast (NETY) than from freeze-tolerant yeast. Furthermore, the rate of leakage of cellular substances form NFTY during incubation exceeded that of FTY, indicating that NFTY is more susceptible to freeze-injury than FTY during frozen-storage. An apparent degradation of phospholipid was observed during incubation of perfermented frozen-cells of NFTY, while little change of phospholipid occurred in FTY, These results suggested that the difference in the sensitivity of yeast might be due to the strength of cell membrane in terms of the degradation of phospholipid by enzymes, phospholipases, attached to cell membranes.

• 한국식품영양학회지
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• 제25권4호
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• pp.903-910
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• 2012

This study was conducted to examine the applicability of muffins and the optimal ratio of batter mixture by adding mugwort with various functions and physiological active substances. In result of examining the quality characteristics of muffins after adding frozen-dried mugwort powder by 0%, 1%, 3%, 5%, or 7%, the moisture retaining capacity of muffin batter was lowest with MPM0, the control group, and the deposition was highest at $17.94m{\ell}$ with MPM0. The pH value of muffin batter was highest at 8.62 with MPM0 and moisture decreased significantly (p<0.001) when more mugwort powder was added to the sample. The brightness increased significantly (p<0.001) when the amount of frozen-dried mugwort powder decreased and redness and yellowness decreased when the addition of mugwort powder increased. The height and volume of mugwort muffins were lowest at 4.75 cm and $135.69m{\ell}$ with MPM7 with the greatest value of frozen-dried mugwort powder. The loss at baking of mugwort muffins was lowest at 2.27% with MPM7. The hardness of mugwort muffins was highest with MPM7 with the highest mugwort powder content. Coagulation and resilience was highest at 0.64 with the MPM0 control group and the chewiness increased significantly (p<0.001) with greater amount of frozen-dried mugwort powder. The appearance of mugwort muffins was highest at 6.1 with MPM5 and the most preferable color and flavors were found with MPM3. Tenderness was highest with the MPM0 control group. Overall preferability was highest with MPM3 with 3% frozen-dried mugwort powder. When adding frozen-dried mugwort powder to muffins, the 3% and control groups mostly showed the highest values, whereas the 5% group and higher groups showed lower values.

• 한국축산식품학회지
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• 제31권1호
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• pp.27-31
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• 2011

To differentiate between frozen-thawed and fresh broiler breast fillets, different methods such as optical microscopy and measurement of drip loss, pH, torrymeter and K-value were performed. A total of 10 samples of fresh and frozen-thawed breast fillets were stored in a refrigerator ($4^{\circ}C$) for 5 d. Optical microscopy of the frozen-thawed breast fillets found structural changes caused by ice crystals, which may have significantly increased drip loss compared to fresh breast fillet. The pH and K-value could not be distinguished between the two breast fillets during storage. However, the torrymeter values of the fresh and frozen-thawed breast fillets were significantly different (p<0.05). The results indicate that both optical microscopy and torrymeter measurement can be effective methods for differentiating between fresh and frozen-thawed breast fillets. However, optical microscopy may be difficult to implement in the marketplace since it requires much time and effort. Thus, the determination of the torrymeter value is the easiest and most rapid instrumental method among those tested for the differentiation of frozen-thawed chicken breast fillet from fresh one.

• 한국축산식품학회지
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• 제18권1호
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• pp.63-74
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• 1998

Recently the high outbreaks of intestinal disease caused by the consumption of frozen dairy foods containing pathogenic bacteria has generated considerable interest in the causative agent such as Listeria monocytogenes and E. coli O157:H7. This study was carried out to detect the above pathogens and compare the microbiological qualities of three commercial forzen yogurt products. The main results obtained were as follows. L. monocytogenes coliforms and E. coli O157:H7 were not detected in the total of seven frozen yogurt samples. For microbiological qualities the viable lactic counts of products manufactured by FA company were about 2.9$\times$108 -1.6$\times$109cfu/ml 1.7$\times$106 cfu/ml for FB's and 1.2$\times$106 cfu/ml for FC's The PH values of FA's FB's and FC's products was in the range of pH 4.1~5.3 and the values of FA's were 4.1~4.6 compared by the pH 5.2~5.3 of FB's and FC's products. During refrigeration of the test samples the survival rates of L. monocytogenes spiked into thawed frozen yogurt sample(FA's FB,s and FC's) were 0.55% 15.61% and 16.89% respectively. On the other hand E. coli O157:H7 and L. monocytogenes were 12.4% and 25.0% for FA's 10.8% and 20.8% for FB's and 10.26% and 22.7% for FC's under 37$^{\circ}C$ storage, As the results described above each frozen yogurt products were different in microbiological qualities. The survival rates of pathogens spiked into the samples increased with the pH of the products. This indicates that the pH or any other factors pre-sumable supressed the growth of E. coli O157:H7 and L. monocytogenes in frozen yogurt products.

• 한국식품과학회지
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• 제46권6호
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• pp.710-715
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• 2014

냉동 복분자의 품질에 대한 연구가 매우 부족하고 고품질 냉동 복분자를 생산하기 위한 냉해동 최적조건 연구가 시급히 필요한 실정이다. 본 연구에서는 국내에서 가장 많이 재배되는 R. occidentalis의 성숙과를 이용하여 냉해동 연구를 수행하였다. 복분자를 수확 직 후 -20, -45, $-70^{\circ}C$ 조건에서 냉동하고 2개월 동안 $-20^{\circ}C$에서 저장한 후 $4^{\circ}C$ 혹은 상온에서 해동하여 복분자의 품질변화를 drip률, 강도, pH, 유리당 함량, 색도 및 anthocyanidin 함량을 중심으로 분석하였다. 분석결과, 냉동 온도에 따라 drip률, 유리당 함량 및 과의 강도가 유의적인 차이가 나타나는 것으로 측정되었다. 그러나 색도, pH, anthocyanidin의 함량 등은 냉동 조건에 따른 변화가 뚜렷하게 나타나지 않았다. 냉동 단면을 비교한 결과, 낮은 온도에서 냉동할수록 세포간 유출수가 현저하게 감소하는 것으로 관찰되었다. 미생물의 오염도는 호기성세균은 물론 효모와 곰팡이도 냉해동을 거치면서 유의적으로 감소하는 것을 확인 할 수 있었다.

• 한국식품과학회지
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• 제14권4호
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• pp.324-329
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• 1982

고등어를 이용하여 어육냉동 steak을 만들어 이것의 가공조건을 구명하고 또한 대두단백질의 첨가가 제품품질에 미치는 효과에 대하여 검토하였다. 고등어 냉동 steak를 가공하기 위해서는 어육에 탄산수소나트륨 0.5%, 식염 1.0%, 중합인산염 0.2%, 글루탐산나트륨 0.2%, 설탕 2.0% 및 향신료로서 고춧가루 0.2%, 후추가루 0.4%, 마늘가루 0.2%와 nutmeg 0.2%를 첨가하여 고기갈이한 다음 $-3^{\circ}C{\sim}-5^{\circ}C$에서 2일간 조온저장 후 동결저장하는 것이 가장 좋았다. 또한 대두단백질을 5% 첨가하므로서 제품의 동결저장중 색조변화, 유리드립생성, 지방산패억제 및 텍스튜어의 개선효과가 있었으며 관능검사 결과로서도 고등어냉동 steak는 동결저장 90일동안 품질이 안정되게 유지되었다.

• 한국식품위생안전성학회지
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• 제38권6호
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• pp.476-482
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• 2023

본 연구는 가열하여 섭취하는 냉동식품 중 빵류 20건 및 서류가공품 30건과 식품접객업소의 조리식품 중 감자튀김 20건을 대상으로 가열조리에 따른 아크릴아마이드 함량을 분석하였다. 에어프라이어를 이용한 냉동식품의 조리 전·후 아크릴아마이드 함량과 식품접객업소 조리식품의 아크릴아마이드 함량을 LC-MS/MS를 이용하여 분석하고 비교하였다. 아크릴아마이드 함량은 에어프라이어 조리 후 빵류 4건에서 0.167-0.401 mg/kg, 서류가공품 24건에서 0.071-0.694 mg/kg으로 나타났으며, 식품접객업소 조리식품은 모든 제품에서 0.118-0.977 mg/kg으로 나타났다. 이 중 국내 아크릴아마이드 권장규격인 1 mg/kg을 초과한 제품은 없었다. 하지만 유럽연합의 benchmark level (0.5 mg/kg)을 초과한 냉동 제품 3건을 튀김기 조리법으로 가열 조리하였을 때, 서류가공품 1건이 국내 권장규격을 초과하여 1.83 mg/kg으로 검출되었다. 아크릴아마이드에 대한 국내 노출량이 증가하는 추세이므로 아크릴아마이드 저감화를 위해 지속적인 평가와 관리가 필요한 것으로 판단된다.

• Food Science and Biotechnology
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• 제16권1호
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• pp.8-17
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• 2007

The main purpose of flavor research using conventional extraction methods, such as solvent extraction, distillation, and dynamic headspace, is to effectively extract, identify, and quantify flavor volatiles present in food matrices. In recent flavor research, the importance of understanding flavor release during mastication is increasing, because only volatiles available in the headspace contribute to the perception of food 'flavors'. Odor potency differs among flavor volatiles, and the physicochemical characteristics of flavor volatiles affect their release behavior and interaction with various food matrices. In this review, a general overview of flavor release and flavor-food interactions within frozen dessert systems is given with emphasis on chemical, physiological, and perceptual aspects. Chemical and sensory analysis methods competent for investigating such flavor-food interactions are illustrated. Statistical analysis techniques recommended for data acquired from such experiments are also discussed.