• Journal of Applied Biological Chemistry
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• 제50권4호
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• pp.234-238
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• 2007

The effects of ultra-fine pulverization on the physicochemical properties of rice starch (RS) were investigated using a high impact planetary mill. After pulverization, RVA characteristics, peak viscosity, break down, and set back values of RS decreased from 274.75 to 9.42 RVU, 214.46 to 6.17 RVU, and 87.80 to 17.00 RVU, respectively. The pasting properties also changed significantly. X-Ray diffractogram revealed RS had four A-type peaks, which disappeared after pulverization. The peak temperature and gelatinization enthalpy of RS using differential scanning calorimetry (DSC) were 13.99 J/g at $75.14^{\circ}C$, whereas the pulverized RS (PRS) had two peaks, 0.13 J/g at $63.88^{\circ}C$ and 1.23 J/g at $101.24^{\circ}C$. DSC measurement showed the retrogradation degree of PRS was lower than that of RS after storage at 4 and $25^{\circ}C$. The enzymatic (${\alpha}$-amylase) digestibilities of RS and PRS were 72.7 and 77.3%, respectively.

• 한국식품영양과학회지
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• 제28권1호
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• pp.107-112
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• 1999

Physicochemical properties and microflora of kimchi stew's sauce were investigated during 6 months at 13oC, 27oC and 37oC to study the changes of its quality. The final pH values in the sauce showed a slight decrease to 4.46, 4.38 and 4.21 during storage at 13oC, 27oC and 37oC, respectively. Color(L, a, b values), salinity, moisture and Aw in the sauce were decreased during storage. However, the values of brix and browning, and the amounts of total sugar, crude protein and crude fat in the sauce were increased during storage. All the reactions occurred more rapidly in the samples stored at 37oC than those stored at 27oC and 13oC. The viable cell counts of aerobic bacteria in the sauce were changed remarkably during storage, but viable cell counts of lactic acid bacteria were decreased. Yeast, mold and E. coli were not found in the above temperatures during storage. Regression analysis between sensory scores and quality characteristics showed that the ΔE value was a major quality index for the deterioration of kimchi stew's sauce. The shelf lives of sauces at 13oC, 27oC, 37oC were estimated to be 24 months, 6 months and 6 months, respectively.

• 동아시아식생활학회지
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• 제10권5호
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• pp.425-430
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• 2000

Physicochemical properties of Kochujang(OK) added onion powder (OK ) were Investigated duringstorage at 20"C The pH value of Kochujang tended to decrease by condition of storage. Initial pH value of OK was significantly lower than that of control, but the difference of pH value was getting smaller during the storage period. In the Process of 90 days storage period, the pH value of OK containing 8 and 10% of onion powder was higher than control. Salt content was lower in OK than in control as the onion content was higher No changes in salt content were observed during the storage process. Reducing sugar was higher in OK than in control, and Its concentration was increased with onion content. Amino acid nitrogen content which was slightly higher in OK than in control increased during 45 days of storage period and tended to decrease afterward. In the sensory attribute data of Kochujang after 3 months of storage period, OK had higher scores in sweetness, color, flavor, and overall acceptability than control, especially the OK with 10% onion powder had the highest scores.scores.

• 동아시아식생활학회지
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• 제7권3호
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• pp.315-324
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• 1997

1.5, 3.0, 4.5, 6.0% active Cl/g starch를 포함하는 sodium hypochlorite 용액으로 pH 7.0에서 감자전분을 산화시켜 이화학적인 성질을 측정하였다. 산화 전분의 카르복실기 함량은 사용한 활성 염소농도에 비례하였고, 물결합력과 알칼리수, 용해도는 산화 정도가 높을수록 증가하였다. 청가와 요오드흡착특성에서는 산화에 의해 아밀로오스 구조가 변화되었음을 알 수 있었고, 광투과도와 DSC에 의한 호화양상에서는 산화 정도가 클수록 낮은 온도에서 호화되는 것으로 나타났다. X선 회절도와 주사전자 현미경으로 살펴 본 전분 입자의 형태로부터 산화는 주로 입자 표면의 무정형 부분에서 일어난 것으로 추정되었다.

• 한국식품조리과학회지
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• 제19권5호
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• pp.624-630
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• 2003

The physicochemical properties and antioxidant activities of commonly consumed espresso and regular coffees, at coffee shops in downtown Seoul, were investigated. Moreover, the characteristics between chain type coffee shops and owner shops were compared using t-tests. The serving temperature and volume of espresso were lower than those for regular coffees. Whereas, the pH and total acidity of espresso were higher than those for regular coffees. Coffees from chain shops, in particular, had a significantly higher pH and lower total acidity than those from owner shops. The L, a and b values of the regular coffees were higher than those of the espresso coffees. With the exception of the a value of regular coffees, all the color values of the coffees from owner shops were higher than those from the chain shops. The intensity of the brownness, soluble solid contents and total phenolic contents of the espresso coffees were about 7∼8, 8∼9 and 4 times higher, respectively, than those of regular coffees. In addition, the free radical scavenging capacities and antioxidant activities of the espresso coffees, using a chemiluminescence assay, were higher than those of regular coffees. Espresso coffees from chain shops, especially, had higher activities of free radical scavenging than those from owner shops. In conclusion, the characteristics of coffees from chain shops were significantly different from those from owner coffee shops.

• 한국식품조리과학회지
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• 제32권3호
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• pp.290-298
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• 2016

Purpose: This study aimed to investigate the effect of grape skin on the physicochemical properties and sensory score of ground pork meat. Methods: Four types of ground pork were evaluated: T0 without grape skin, T1 with 0.3% grape skin, T2 with 0.7% grape skin, and T3 with 1.0% grape skin. Results: There was no significant group wise difference in VBN content, L-value, b-value, chemical composition of raw and cooked meat, cooking yield, water holding capacity, moisture retention, fat retention, hardness, springiness, cohesiveness, gumminess, chewiness, taste, texture, juiciness, or palatability. Total polyphenol content was highest in T3, and DPPH radical scavenging activity was highest in T2 and T3 (p<0.001). The pH was highest in T0, and was lowest in T3 (p<0.001). The a-value of T2 and T3 were significantly higher than that of T0 (p<0.05). Flavor was highest in T2 among samples (p<0.01). Conclusion: The study results suggest that grape skin may be a useful ingredient in ground pork meat in terms of antioxidant potential, color and flavor.

• 한국수산과학회지
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• 제55권4호
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• pp.408-416
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• 2022

This study investigated the physicochemical properties and physiological activities of jelly prepared from gelatin, sugar, bokbunja extract, and different amounts (0, 0.5, 1, 2 and 3%) of fermented sea tangle Saccharina japonica powder (FSP). The jelly moisture, pH, and sugar content slightly increased with increasing the FSP content. Hardness, springiness, gumminess, chewiness, and cohesiveness also increased with increasing FSP concentration. Jelly antioxidant activity did not change significantly with increasing FSP. In contrast, alcohol dehydrogenase and aldehyde dehydrogenase activities in the jellies increased significantly with increasing FSP concentration. β-secretase inhibitory activity in jellies also increased with increasing FSP concentration. Jellies containing 0.5 or 1% FSP achieved the highest overall sensory acceptance scores. Taken together, these data indicate that addition of FSP to jelly appears to improve its quality and physiological activities.

• 한국축산식품학회지
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• 제43권3호
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• pp.540-551
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• 2023

Milk protein concentrate (MPC) is widely used to enhance the stability and texture of fermented dairy products. However, most research has focused on yogurt products, and the effects of MPC on sour cream characteristics remain unknown. Therefore, we investigated the effects of different MPC levels (0%, 1%, 2%, and 3% w/w) on the rheological, physicochemical, microbiological, and aroma characteristics of sour creams in this study. We found that MPC supplementation stimulated the growth of lactic acid bacteria (LAB) in sour creams, resulting in higher acidity than that in the control sample due to the lactic acid produced by LAB. Three aroma compounds, acetaldehyde, diacetyl, and acetoin, were detected in all sour cream samples. All sour creams showed shear-thinning behavior (n=0.41-0.50), and the addition of MPC led to an increase in the rheological parameters (η_a,50, K, G', and G"). In particular, sour cream with 3% MPC showed the best elastic property owing to the interaction between denatured whey protein and caseins. In addition, these protein interactions resulted in the formation of a gel network, which enhanced the water-holding capacity and improved the whey separation. These findings revealed that MPC can be used as a supplementary protein to improve the rheological and physicochemical characteristics of sour cream.

• 한국식품영양과학회지
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• 제23권5호
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• pp.816-821
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• 1994

The physicochemical properties and cooking qualities of six cultivars of covered barley, four malting barley and six naked barley were investigated. The 1, 000 kernel weight was heavier in the malting barley and ash content was the highest in covered barley. The varietal variation of amylose content was 17.7 to 20.2%. $\beta$-Glucan viscosity was generally lower in the malting barely, and varied greatly among barley cutivars with 2.16 to 8.47 cSt. The pearling rate was highest in naked barley with a mean of 75.5% and protein content of aw and pearled barely was significantly different with cultivars. In the cultivars tested, Doosan 8, Youngsan and Iri 5 showed the higher milling rate. Amylose patterns showed that the covered barley cultivars has lower gelatinization temperature and higher peak height and height at 50 $^{\circ}C$ than the malting and naked barley. The water absorptions were highest in covered barley cultivars , and lowest in naked barley cultivars. The soluble solid was highest in naked barley cultivars.

• 한국식품저장유통학회지
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• 제6권1호
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• pp.7-10
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• 1999

Physicochemical properties of Satsuma mandarin(Citrus unshiu Marc. var. miyagawa) harvested in middle of November according to production areas of Cheju were investigated. Peel thickness of citrus fruits was ranged from 2.54mm to 3.13mm, and it was lower on fruits harvested in western areas than those of other areas in Cheju. Soluble solids were ranged from 10.1 to 12.0$^{\circ}$Brix, and it was lower on fruits harvested in southern areas. Acid contents of citrus juice were ranged from 1.28% to 1.42%, it was higher on fruits harvested in eastern areas, specific gravity of citrus fruits was ranged between 0.86 and 0.88. Flesh ratio was ranged from 75.1% to 77.6%, it was lower on fruits harvested in southern areas. Soluble solids, acid content and specific gravity harvested in southern areas of below 100m and over 150m sea level altitude were 11.8 and 11.2, 1.43% and 1.40%, 0.87 and 0.9, respectively. Fruits quality harvested in southern areas was better, compared to other harvest areas of Cheju.