• Journal of Microbiology and Biotechnology
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• v.30 no.9
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• pp.1404-1411
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• 2020

Lactic acid bacteria (LAB) play an important role in dairy fermentations, notably as cheese starter cultures. During the cheese production and ripening period, various enzymes from milk, rennet, starter cultures, and non-starter LABs are involved in flavor formation pathways, including glycolysis, proteolysis, and lipolysis. Among these three pathways, starter LABs are particularly related to amino acid degradation, presumably as the origins of major flavor compounds. Therefore, we used several enzymes as major criteria for the selection of starter bacteria with flavor-forming ability. Lactococcus lactis subsp. lactis LDTM6802 and Lactococcus lactis subsp. cremoris LDTM6803, isolated from Korean raw milk and cucumber kimchi, were confirmed by using multiplex PCR and characterized as starter bacteria. The combinations of starter bacteria were validated in a miniature Gouda-type cheese model. The flavor compounds of the tested miniature cheeses were analyzed and profiled by using an electronic nose. Compared to commercial industrial cheese starters, selected starter bacteria showed lower pH, and more variety in their flavor profile. These results demonstrated that LDTM6802 and LDTM6803 as starter bacteria have potent starter properties with a characteristic flavor-forming ability in cheese.

• Korean Journal of Agricultural Science
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• v.16 no.2
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• pp.179-200
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• 1989

Mucor miehei rennet(MR) was added as calf rennet(CR) substitutes in the fixed amounts of mixed rennets in making Camembert cheese. The conditions in the variations of chemical composition: water-soluble nitrogen, non-caseinic nitrogen, non-proteinic nitrogen, amino nitrogen, ammoniacal nitorgen, electrophoresis, molecular fractionation, mineral distribution, texture characterisitics, free amino acids and free fatty acids, were checked up with the sensory test and the chesse yields at each ripening period. The results obtained by investigating the utility of Mucor rennet were summarized as follows: 1. CR chesse, MR cheese and the mixed-rennet chesse failed to show any significant difference in their yields of 15%. 2. The contents of protein, fat and ash in MR cheese gave lower value than CR cheese did and with progress of ripening lactose decreased rapidly after 14 days of ripening. The difference among the rate of addition of mucor rennet was not recognized. 3. The WSN contents of 5 fresh sample chesse were from 14.7% to 17.3% and WSN increased from 39.7% to 41.0% with progress of ripening. After 21 days of ripening MR chesse had more WSN than CR cheese did. In NCN and ammoniacal nitrogen MR cheese showed higher value. 4. As the ripening progressed, MR chesse showed more cystein, phenylalanine and proline than CR chesse did but it failed to show any increase in aspartic acid, threonine and glutamic acid etc. 5. In the content of free fatty acid MR chesse showed higher value than CR cheese did and with the progress of ripening fatty acids increased from 8.36 mEq to 26.36 mEq but did not show any significant difference in the cheese types by the coagulant ratio. 6. Ca contents in the sample chesse were 0.238-0.27%, Mg 0.019-0.022%, Na 0.910-1.047%, and K 0.175-0.200%. The important non-sedimentable Ca in casein remained from 61 % to 77% without regard the ripening periods and added-rennets and Mg remained from 59.1% to 92.5% in non-sedimentable and water-soluble conditions. 7. In the fractionation of protein by ultrafilteration, MW> $5{\times}10^4$ decresed from 95% at the beginning period of ripening to 45% and MW< $10^4$ increased from 0.2% to 38% and definite caseinolysis was shown in all samples. 8. All the cheese showed to different electrophoretic patterns for the added-amounts of mucor rennet in the 14 days of ripenig. In the 28 days or ripening, MR cheese kept some bands on the patterns compared with CR cheese. 9. In vitro digestibility increased from 81.48-94.81 % to 94.47-98.61% but failed to show any significant difference in the cheese types by the coagulant ratio. 10. In hardness, MR cheese showed lower value compared with CR cheese as the ripening progressed. 11. The results of the sensory test failed to show any difference in flora rind, feelings in mouth and hands, deep structure, flavor and bitterness between CR Camembert cheese and MR Camembert chesse.

• Food Science of Animal Resources
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• v.24 no.2
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• pp.156-163
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• 2004

This study was carried out to investigate the improvement of stretchability in Mozzarella cheese based on the influence of various factors such as starter type, fat content, salt content and stretching temperature. To do this study, stretchability, meltability, fat leakage and the change of soluble nitrogen compound were measured during storage of the Mozzarella cheese at 4$^{\circ}C$ for 10 weeks. When L bulgaricus starter was added, stretchability of the cheese was excellent and cheese manufactured with starter of L bulgaricus and L. bulgaricus : Str. thermophilus = 1:2 improved meltability because of high soluble nitrogen compound. When salt content of cheese was 0.5％, this resulted in extreme deterioration of quality in regard to stretchability, meltability and fat leakage at five weeks and when salt content of cheese was 0.5, 1.0 and 1.5％, soluble nitrogen compound was 4.49, 4.45 and 2.61 ％ at one week and 19.71, 19.44％ and 17.07％ at eight weeks, respectively. Stretchability was good at high stretching temperature, and cheese with stretching at 60'C showed poor meltability at the first stage, but this cheese had good meltability in process of time because increase in soluble nitrogen compound was high at low stretching temperature.

• Journal of Dairy Science and Biotechnology
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• v.14 no.2
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• pp.147-155
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• 1996

This experiment was carried out to find general composition and mineral contents such as Ca, P, Mg, Na, K and Fe of domestic commercials Mozzarella cheese. Twenty-five products of 5 company were analyzed. The results obtained were as fellow : The average contents of moisture, fat, fat in dry matter, protein and ash in Mozzarella cheese were 49.01, 22.54, 44.16, 24.36 and 2.55%, respectively and average pH was 5.29. The average contents of Ca, P, Mg, Na, K and Fe were 696.44, 466.31, 22.08, 310.8, 82.84 and 0.36mg, respectively. Among products, product C was highest in levels of Ca, P and Mg, which were 797.4, 536.6 and 25.5mg, respectively, Na was highest for product A which contained 450.8mg. K and Fe were highest for product B which contained 98.9 and 0.51mg, respectively. Generally, the ratio of Ca to P was 1.5 : 1 and within the proper range. It was found that 645g of Mozzarella cheese was able to fully meet the daily recommendation of minerals including Ca, P and Na.

• Journal of Food Hygiene and Safety
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• v.35 no.6
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• pp.552-560
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• 2020

Listeria monocytogenes is a highly pathogenic gram-positive bacterium that is easily isolated from cheese, meat, processed meat products, and smoked salmon. A zero-tolerance (n=5, c=0, m=0/25 g) criteria has been applied for L. monocytogenes in cheese meaning that L. monocytogenes must not be detected in any 25 g of samples. However, there was a lack of scientific information behind this criteria. Therefore, in this study, we conducted a risk assessment based on literature reviews to provide scientific information supporting the baseline and to raise public awareness of L. monocytogenes foodborne illness. Quantitative risk assessment of L. monocytogenes for cheese was conducted using the following steps: exposure assessment, hazard characterization, and risk characterization. As a result, the initial contamination level of L. monocytogenes was -4.0 Log CFU/g in cheese. The consumption frequency of cheese was 11.8%, and the appropriate probability distribution for amount of cheese consumed was a Lognormal distribution with an average of 32.5 g. In conclusion, the mean of probabilities of foodborne illness caused by the consumption of cheese was 5.09×10-7 in the healthy population and 4.32×10-6 in the susceptible population. Consumption frequency has the biggest effect on the probability of foodborne illness, but storage and transportation times have also been found to affect the probability of foodborne illness; thus, management of the distribution environment should be considered important. Through this risk assessment, scientific data to support the criteria for L. monocytogenes in cheese could be obtained. In addition, we recommend that further risk assessment studies of L. monocytogenes in various foods be conducted in the future.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.14 no.1
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• pp.59-77
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• 2003

This study was carried out to find a cholesterol removal rate, flavor development, and bitter amino acid productions in Cheddar cheese treated with -cyclodextrin ($\beta$-CD): l) Control (no homogenization, no $\beta$-CD), and 2) Milk treatment (1000 psi milk homogenization, 1 % $\beta$-CD). The cholesterol removal of the cheese were 79.3%. The production of short-chain free fatty acids (FF A) increased with a ripening time in both control and milk treated cheese. The releasing quantity of short-chain FFA was higher din milk treated cheese than control at 5 and 7 mo ripening. Not much difference was found in neutral volatile compounds production between samples. In bitter-tasted amino acids, milk treatment group produced much higher than control. In sensory analysis, texture score of control Cheddar cheese significantly increased, however, that in cholesterol-reduced cheese decreased dramatically with ripening time.

• Journal of Dairy Science and Biotechnology
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• v.40 no.1
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• pp.1-14
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• 2022

The safety and storage periods of various foods, including dairy products, can be affected by a variety of internal and external factors. Therefore, all foods have a risk of deterioration after storage for a certain period of time for many different reasons. Among dairy products, cheese is enriched in necessary nutrients; however, it can also easily undergo physical, chemical, and biochemical changes under various conditions. Therefore, the storage period of cheese is an important issue. If various factors that can affect the safety and storage period of cheese can be controlled, the safety of cheese can be preserved and its storage period extended. This review of the literature published on the issue summarizes various state-of-the-art technologies currently used to extend the storage period of cheese without affecting its quality. This basic data will inform future research concerning the storage period of various cheeses.

• The Korean Journal of Food And Nutrition
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• v.29 no.4
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• pp.583-594
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• 2016

The purpose of this study was to determine the optimal mixing ratio of olive oil, parmesan cheese, and nuts for preparation of pesto with spinach. Based on a surface response methodology (RSM), the independent variables were olive oil (100~300 g), parmesan cheese (25~75 g) and nuts (12~36 g). The dependent variables were physico-chemical properties as pH, color values (L, a, and b values), viscosity and sensory evaluation. pH decreased with increasing parmesan cheese levels. The L value decreased and the a and b values increased with increasing olive oil levels. Viscosity was negatively correlated with olive oil levels but positively correlated with the amounts of parmesan cheese and nuts. The addition of oil exerted a positive effect on gloss, and oily taste. In the sensory evaluation, the values of appearance, color, flavor, taste and overall acceptance were in the range of 4.4~7.2, 3.7~7.4, 4.4~7.1, 3.9~7.3 and 3.5~7.6, respectively. The sensory evaluation results showed significant values in appearance (p<0.01), flavor (p<0.01), taste (p<0.01) and overall acceptance (p<0.05). The optimal amounts of spinach pesto with olive oil, parmesan cheese, and nuts were determined by numerical optimization of a canonical model and graphical optimization. The optimal amounts were 175.29 g of olive oil, 49.51 g parmesan cheese, and 27.37 g of nuts per 100 g of spinach.

• Korean Journal of Food Science and Technology
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• v.8 no.2
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• pp.107-112
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• 1976

This experiment has been carried out to study the changes of caseins is Gouda-type cheese during ripening by the use of DEAE-cellulose column and polyacrylamide gel electrophoresis. The results obtained were as follow: 1. The amount of water soluble nitrogenous compounds in the cheese ripened for 2 and 4 months was 19.03% and 30.61% for total nitrogen in the cheese, respectively. On the other hand, the amount of 5% NaCl soluble nitrogenous compounds in the cheese increased to 41.13% for 2 months ripening, but it decreased to 22.61% at 4th month. 2. By DEAE-cellulose column, various nitrogenous compounds of Gouda-type cheese were fractionated into 5 major and several minor peaks. The proportion of some fraction areas to the whole increased with the ripening period and the others decreased. 3. Electrophoretic patterns of various nitrogenous compounds in a 4-month-old cheese showed 5 and 8 bands, repectively. 4. Sixteen amino acids were identified in soluble and precipitable compounds at 12% TCA in a 4-month-old cheese.

• Journal of Dairy Science and Biotechnology
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• v.33 no.1
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• pp.69-73
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• 2015

The world is presently facing key challenges due to the population explosion, shortages in renewable sources of energy, and environmental problems. One important aspect of ecological intensification is the use and improvement of marginal lands and spaces often ignored, until now. Goats are known to be well adapted to scrubs, forage trees, and rangelands. Goats could contribute marginally, but significantly, to the growing demand for meat without using arable lands. Since 2000, there were 752 million goats globally, and goat livestock increased by 26.8% in 2010, accounting for 954 million heads. Goats are widespread due to their high adaptability to different environmental conditions and nutritional regimes, high productivity, and low maintenance cost. A significant growth in goat number was noticed in the period 2000~2010 in the Netherlands (+113.83%), in spite of the 9.75% decrease in EU-27. A cheese making goat farm in the Netherlands showed how it can survive in the one fifth size of the average. It may be a good model for the Korean goat industry since it uses seasonal breeding and results in reduced "goaty" flavor in the cheese.