• Food Science and Biotechnology
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• 제16권4호
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• pp.590-593
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• 2007

The textural properties of doughs mixed with L-ascorbic acid (AA), trypsin hydrolyzed gluten peptide (THGP), and a mixture of AA-THGP were investigated using texture analyzer under the fermentation of the full formula and the freezing process. The full formula dough (FFD) required a shorter mixing time than the flour and water formula dough (FWD). The maximum resistance (Rmax) values of both the unfrozen and frozen doughs were lower for the FFD. The effects of AA and THGP additions were not significant (p<0.01) in FFD, however, they were significant in FWD. The freezing effect was significant (p<0.0001) for FFD, indicating that yeast fermented dough was much more sensitive to damage from freezing, which subsequently affected dough strength. Additions of AA (p=0.0026) and THGP (p=0.0097) had a significant effect on the extensibility (E-value) of unfrozen FWD, where THGP increased and AA decreased the E-value. However, freezing did not significantly effect the extensibilities of FWD (p=0.64) or FFD (p=0.21). The area of FFD was lower than the area of FWD for both the unfrozen and frozen doughs. However, the frozen dough mixed with THGP alone had the largest area overall. The addition of additives did not result in significantly different (p<0.01) areas under the curve, except in the frozen FFD. Freezing caused a statistically significant difference in the area of FWD (p=0.0045).

• Food Science and Biotechnology
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• 제15권5호
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• pp.805-813
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• 2006

The quality of frozen bread dough made with the milk proteins casein (C), whey (W), and the gums sodium alginate (A) and ${\kappa}$-carrageenan (K), was investigated to develop methods to suppress the deterioration of the frozen dough quality. The control had a lower dough volume than dough with additives during freeze-thaw cycles. In bread stored at $5^{\circ}C$, the moisture content of bread prepared with whey plus sodium alginate (WA) decreased less than that of the control. The control also had a lower specific loaf volume than breads made with added milk proteins and gums. The hardness of the control bread and bread made with casein plus sodium alginate (CA) and whey plus ${\kappa}$-carrageenan (WK) increased during freeze-thaw cycles, although that of the control increased more than the others. There was no significant difference in sensory preference among breads with and without milk proteins and gums. Addition of CA and WA improved the baking quality by reducing the deterioration of frozen dough and retarding the staling of bread.

• 한국식품조리과학회지
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• 제9권3호
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• pp.230-238
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• 1993

The objectives of this study were to provide the basic data for the consumer education and for the new product development by surveying housewives'demands concerning prepared frozen or refrigerated foods and by surveying industry's practices and opinions concerning new product development. 804 housewives and 14 manufacturing companies of prepared frozen or refrigerated foods were surveyed. Data from housewives were analyzed by using SPSS-X progrm in terms of $x^2$-test, one-way ANOVA, t-test. The results of study are summarized as follows : 1. Frozen dumpling, frozen meat, surimi, ham and sausage were identifed as the most frequently used food items by housewives. The mean storage period for either prepared frozen or refrigerated foods was less than 15 days. 2. Housewives with higher educational background showed the greater concerns in packing and sanitary conditions, convenience in cooking procedures and brand name of the product than their counterparts. 3. Most housewives'purchasing motive for prepared frozen or refrigerated foods was the convenience of the cooking procedures(71.1%). Among the member of family, children(72.8%) specially liked prepared frozen or refrigerated foods. 4. Housewives'demands for prepared frozen or refrigerated foods were 'price reduction'and 'nutrition fortification'. These were in accordance with the companys'opimons. 5. Most wanting new product developments from the housewives perspectives were beverages (37.7%), stir-fried menu items(36.1%), pan-fried menu items(34.0%), stewed menu items(30.3%) and soups(20.4%). In case of stew and soups, the industry did not have a plan to develop those menu items.

• 한국식품영양학회지
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• 제26권4호
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• pp.772-782
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• 2013

A study is undertaken to examine the effects of the additional frozen blueberry powder and anthocyanin powder extracted from black beans to quality attributes of pound cakes. Frozen blueberry powder and anthocyanin powder extracted from black beans are being added to the flour at a ratio of 0.5, 1.5, 2.5, and 3.5% respectively. The antioxidant activity is highly correlated with the total phenolic and total flavonoids contents of frozen blueberry powder and anthocyanin powder extracted from black beans of pound cakes, respectively (r=0.8423, p<0.001 r=0.9449, p<0.001). The quality characteristics of the specific volumes decreased significantly with increasing substitution levels of frozen blueberry powder and anthocyanin powder extracted from black beans (p<0.01). The lightness significantly decreased with increasing frozen blueberry powder and anthocyanin powder extracted from black beans of pound cakes' crusts and crumbs (p<0.01). The hardness, chewiness and gumminess tend to reduce, while the cohesiveness increase in both powders. The consumer acceptability score for 0.5~3.5% of frozen blueberry powder and anthocyanin powder extracted from black beans pound cakes ranked significantly (p<0.01) higher than those of the other groups according to taste, flavor and overall preferences. These results show that frozen blueberry powder and anthocyanin powder extracted from the black beans are a good ingredient for increasing consumer acceptability and overall healthy.

• 산업식품공학
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• 제14권1호
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• pp.14-20
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• 2010

본 연구에서는 냉동요구르트 제조 시 trehalose와 sorbitol 첨가가 유산균의 동결변성방지 및 향기성분의 변화에 미치는 영향을 조사하고자 실시하였다. 요구르트를 L. bulgaricus와 S. thermophilus 단독균주 및 혼합균주로 발효시켰을 때 처리구 모두 trehalose와 sorbitol 첨가에 의한 발효과정 중 유산균의 증식효과는 나타나지 않았다. 요구르트를 6주간 냉동저장하는 동안 trehalose와 sorbitol 첨가에 의한 모든 처리구에서 유산균수의 차이가 없었으며, MRS 액상배지에 trehalose와 sorbitol 을 각각 2%, 5% 첨가하여 6주간 냉동저장하였을 때는 5% trehalose 처리구의 동결변성방지 효과가 가장 우수한 것으로 나타났다. 냉동저장 기간 동안 고형분 함량이 12%인 처리구와 20%인 처리구의 생균수는 큰 차이가 나타나지 않아 고형분 함량 차이에 의한 trehalose와 sorbitol 효과에는 차이가 없는 결과를 나타내었다. 요구르트의 동결과 해동을 반복하였을 경우 trehalose와 sorbitol 모두 2% 첨가구보다 5% 첨가구가 우수한 동결변성방지 효과를 나타내었다. 전반적으로 Trehalose 첨가구가 sorbitol 첨가구보다 2%, 5% 모두 동결변성방지 효과가 좋은 결과를 나타내었다. Trehalose와 sorbitol을 첨가하여 요구르트를 제조하였을때 향미성분의 함량은 대조구와 유사하였으며 일반적인 요구르트의 향미를 나타내었다. 냉동저장 중 요구르트 향미성분은 손실되거나, 함량비율의 변화가 발생하지 않았다. 이상의 결과로부터 요구르트의 풍미에는 영향을 미치지 않으면서 냉동저장에 의한 유산균의 동결변성방지제로서의 trehalose첨가가 냉동요구르트의 유산균 안정화에 효과가 있다고 하겠다.

• 한국축산식품학회지
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• 제40권3호
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• pp.350-361
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• 2020

Quality control of meat products is one of the main concerns of consumers, governmental control authorities, and retailers. The purpose of this study was to employ ribose-induced Maillard reaction in detection of meat adulteration and differentiation of fresh-chilled from frozen-thawed minced veal. The browning intensity was assessed through measuring the absorbance at 420 nm with a spectrophotometer as well as the direct analysis of the color and pH. The results showed that CIE b*, CIE a*, and A_420* values in the extract of fresh-chilled veal were significantly (p<0.05) higher than frozen-thawed samples. The extract of frozen meat samples stored at -18℃ became significantly darker and more yellowish compared to -4℃. The results showed that the A_420* value in the frozen-thawed veal stored at -4℃ and -18℃ was reduced by approximately 17.22±3.53% and 11.68±2.49%, respectively, compared with fresh-chilled veal. The findings also showed that the storage temperature of minced veal and the heating time in this reaction had a significant effect on all tested variables (p<0.0001). The proposed method can be considered as an easy, quick, and inexpensive test for differentiating between the fresh-chilled and frozen-thawed minced veal.

• 한국식품과학회지
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• 제43권4호
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• pp.509-512
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• 2011

동결건조 쌀죽의 품질특성에 미치는 동결속도의 영향을 조사하기 위하여 쌀죽을 -20, -40, -70$^{\circ}C$의 동결 온도에서 동결시킨 후 동결건조시킨 제품을 제조하여 이들 제품의 미세구조, 물리적 강도, 조직감 및 재수화율을 조사하였다. 전자주사현미경을 통한 이들 제품의 미세구조를 관찰한 결과 완만동결(-20$^{\circ}C$)시킨 것이 급속동결(-70$^{\circ}C$)에 비해 공극의 크기가 크고 그 수가 적었다. 반면에 급속동결시킨 제품은 보다 조직이 치밀하고 물리적인 강도가 유의적(p<0.05)으로 큰 값을 나타냈다. 수화복원율은 -20$^{\circ}C$에서 동결시킨 제품이 -40, -70$^{\circ}C$에서 동결시킨 제품보다 높았다. 따라서 품질이 우수하고 사용이 간편한 동결건조 쌀죽을 제조하기 위해서는 최적의 동결 온도의 선택이 필수적임을 알 수 있었다.

• 한국식생활문화학회지
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• 제18권2호
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• pp.105-110
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• 2003

김치를 $10^{\circ}C$에서 8일간 숙성시켜 산도 $0.6{\sim}0.7%$로 숙성된 김치를 $-70^{\circ}C$와 $-20^{\circ}C$로 냉동하여 $-20^{\circ}C$에서 저장하면서 배추 조직의 elasticity, hardness, 세포 조직의 변화, 드립양을 실험한 결과는 다음과 같다. $-70^{\circ}C$에서 급속 동결한 것과 $-20^{\circ}C$에서 완만동결한 냉동 김치중 배추조직의 elasticity는 냉동저장 15일까지 감소하다 일정하게 유지되었고 hardness는 거의 변화가 없었으며 냉동 방법에 따른 변화도 거의 나타나지 않았다. 투과 전자현미경으로 관찰한 결과 control의 경우 세포벽이 매우 두꺼우며 세포의 모양들이 잘 보존되어 있는 것을 볼 수 있었고 $-20^{\circ}C$로 냉동 처리하여 해동시킨 세포벽들은 많이 손상되어 있음을 볼 수 있었으며 $-70^{\circ}C$로 급속 냉동 시료의 경우 세포벽의 손상 정도가 $-20^{\circ}C$로 냉동 처리한 시료보다 덜 파괴되어 있음을 볼 수 있었다. 한편 냉동 저장기간 동안 드립의 손실량의 변화는 $-70^{\circ}C$로 냉동 처리한 시료의 드립양은 $3{\sim}4%$정도로 $-20^{\circ}C$로 냉동 처리한 시료의 $5{\sim}6%$에 비해 적은 것을 알 수 있었다.

• 한국식품저장유통학회지
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• 제20권3호
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• pp.296-303
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• 2013

본 연구에서는 동결채소의 저장 중 품질 변화를 측정하여 동결채소의 장기저장 가능성과 이용 가능성을 모색해 보고자 하였다. 수확직후 여러 가지 채소는 선행실험을 통한 최적 조건에서 blanching 처리한 후 $-40^{\circ}C$에서 24시간 동안 급속동결시켜 $-20^{\circ}C$에서 저장하면서 분석하였다. 동결시킨 취나물, 콩나물, 얼갈이배추, 애호박 및 대파는 저장 기간 12개월 동안 색도의 증가와 감소가 크게 나타나지 않았다. 취나물, 애호박 및 대파의 경도는 저장기간 동안 비슷한 수준을 유지하였고, 얼갈이배추는 약간 증가하는 경향을 나타내었다. 반면에 콩나물의 자엽부와 배축부는 저장 6개월째에 경도가 큰 폭으로 증가하는 경향을 나타내었다. 저장기간 동안 취나물의 총균수는 $10^3$ CFU/g 수준을 콩나물, 얼갈이배추, 애호박 및 대파는 $10^2$ CFU/g 수준을 유지하였으며, 대장균군은 모든 시료에서 검출되지 않았다. 관능검사는 외관, 색, 이취, 조직감 그리고 맛 등의 전반적인 품질 요소들을 종합하여 전체기호도를 조사한 결과 5점을 marketable의 한계점으로 두었을 때 저장기간에 따른 동결채소의 상품성에는 큰 문제가 없는 것으로 나타났다. 따라서 동결 취나물, 콩나물, 얼갈이배추, 애호박 및 대파는 동결저장 12개월까지 저장 안전성이 있는 것으로 판단된다.

• 한국축산식품학회지
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• 제40권3호
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• pp.444-460
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• 2020

This study was conducted to investigate the effects of freezing and storage temperature (-18℃, -50℃, and -60℃) on the physicochemical properties of pork neck and chicken leg meat in home-scale deep freezers. Pork neck was cut into a thickness of 3 cm (9×9×3 cm, 150 g), individually packed in air-containing packages, and stored at different temperature (-18℃, -50℃, and -60℃) for 6 months. Chicken leg meats were prepared (10 cm long, weighing 70 g) and packed in the same manner. Frozen samples were thawed at 2℃. Physicochemical properties such as thawing loss, cooking loss, water-holding capacity, color, volatile basic nitrogen (VBN), and thiobarbituric acid reactive substances (TBARS) were evaluated. The samples frozen by deep freezing (-60℃) was favorable with respect to thawing loss, color, and VBN. Samples frozen at -60℃ had lower values of thawing loss and VBN than those frozen at -18℃ for all storage periods (p<0.05). Color parameters were more similar to those of fresh meat than to those of samples frozen at -18℃ for 6 months. The TBARS of all samples were below 0.3 mg malondialdehyde/kg, thereby indicating oxidative stability of lipids. Consequently, deep freezing at -60℃ may be acceptable for maintaining the quality of fresh pork neck and chicken leg meat for 6 months without deterioration.