• Journal of Dairy Science and Biotechnology
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• v.33 no.3
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• pp.203-207
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• 2015

The majority of food drying processes are based on the use of thermal energy. However, such methods may deteriorate the quality of the final product. Freeze-drying is one of the most useful processes for drying thermosensitive substances. Food that contains beneficial bacteria, for example, is susceptible to heat treatment, but during freeze-drying beneficial bacteria are preserved in these food items. The primary goals of this study were to develop yogurt snacks and to compare the viability of lactic acid bacteria (LAB) in yogurt snacks under different freeze-drying temperatures. In addition, the survival of LAB during storage was investigated. Survival of LAB in freeze-dried yogurt snacks gradually decreased over 16 weeks of storage. LAB had a residual viability of 25.5% after 16 weeks of storage at room temperature. LAB survived better in freeze-dried plain yogurt snacks than in freeze-dried strawberry yogurt snacks during storage. Freeze-dried yogurt snacks contained 11.9% fat, 57.1% carbohydrate, and 18.7% protein. In conclusion, the viability of LAB in freeze-dried yogurt snacks depends on the temperature during freeze-drying: the higher the freeze-drying temperature, the lower the viability of LAB in yogurt snacks. The viability of LAB in yogurt snacks was also dependent on the moisture content and nutritional value.

• Korean Journal of Human Ecology
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• v.12 no.2
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• pp.265-273
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• 2003

The aim of this study was to investigate the effect d concentrated fermented milk on the improvement of defecation in female students with constipation. This yogurt was fermented with Bifidobacterium, L. acidophilus, and S. thermophilus and supplemented with oligosaccharides, dietary fiber, and yeast and mushroom extracts. 44 female students with constipation were sampled as subjects and fed 150ml fermented milk per day for 2 weeks period. After each defecation, the subjects were examined for the status of stool evacuation by questionnaires. The frequency of stool evacuation, fecal amount, time spending for evacuation, fecal color and shape, and refreshing feeling after evacuation were remarkably improved after ingestion of fermented milk for 2 weeks. These effects were greater in the heavy constipation group than in the mild group. The fecal odor did rot decrease significantly after 2 weeks of intake of fermented milk, but the odor thended to decrease after the intake of fermented milk These results indicated that the ingestion of concentrated fermented milk is effective to improve the constipation.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.583-591
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• 2022

The purpose of this study was to determine the incidence of dental erosion according to the type of lactic acid bacteria fermented oil and to identify a method for preventing dental erosion. For the lactic acid bacteria fermented milk, liquid fermented milk, condense-stirred type fermented milk, and condense-drink type fermented milk were used, and bovine tooth specimens used in the experiment were used. As a method to prevent dental erosion, the method of adding calcium to the lactic acid bacteria fermented milk, the method of applying high and low concentrations of fluoride to the teeth before exposure to the lactic acid bacteria fermented milk, and the method of applying these two methods together were measured to measure the preventive effect of dental erosion. As a result of immersing the specimen in the experimental beverage, the surface hardness of liquid fermented milk decreased the most. When comparing the difference in surface hardness before and after prophylaxis care, the Ca 2% group and the NaF 0.05%+Ca 0.5% group showed no significant difference from the negative control group, confirming that it is an effective method for preventing dental erosion. However, considering the change in taste and the stability of ingredients, a method of adding calcium at a low concentration rather than adding a high concentration of calcium is proposed. Therefore, it is recommended to use low-concentration calcium and low-concentration fluoride together to recognize the possibility of dental erosion when ingesting lactic acid bacteria and to prevent dental erosion caused by it.

• Journal of Korean society of Dental Hygiene
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• v.21 no.5
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• pp.507-515
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• 2021

Objectives: The aim of this study was to evaluate the extent of the potential erosion of enamel induced by three different types of commercial fermented milk using the pH cycle model. Methods: Specimens were treated and soaked up in three types of fermented milk and in mineral water for 10 min, four times a day for 8 days, and all of the specimens were immersed in artificial saliva outside of treatment times. The microhardness of the surface was measured by a microhardness tester, and a scanning electron microscope (SEM) was used to identify the enamel surface morphology. Results: The differences in the surface microhardness (ΔVHN) of enamel were different among the groups (p<0.05). The four groups were in descending order of ΔVHN: the liquid type group, condensed-drink type group, condensed-stirred type group, and control group. The liquid type group had a higher ΔVHN than the other two fermented milk groups (p<0.05). Based on SEM observation, the most severe surface damage was due to the liquid type of fermented milk. Conclusions: Customers' careful discretion is advised when purchasing these types of fermented milk. This information is anticipated to be of much value in the prevention of dental erosion.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.358-366
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• 2009

Lactic acid bacteria worked positively on gastrointestinal tract and oral environment. So I selected commercial five fermented milks and milk, and then I evaluated their effect of growth inhibition and biofilm formation of cariogenic bacteria, Streptococcus mutans. And also calculated the acidity, buffering capacity, concentration of Ca and P ion and pH change of those drinks. After adding S. mutans to fermented milks viable cell count of S. mutans in milk was not statistically different but those in all fermented milks were decreased as concentration of fermented milk increased. When I measured the amount of formed biofilm in 10% fermented milks and milk with S. mutans and compared with those without S. mutans, the amount was decreased in Active GG and Bulgaris while being increased in Tootee, Ace and milk(P<0.05). The fermented milk with the lowest pH value was E5(3.48${\pm}$0.01), and the highest was Bulgaris(4.19${\pm}$0.02). pH change of the fermented milks and milk with S. mutans was measured. The highest acid producing fermented milk was Bulgaris, and followed by Active GG, Ace, Tootee, E5, Milk. These results indicated that fermented milks had caries activity due to the value of initial acidity and acid producing capacity. But, concentrated fermented milks had the inhibitory effect against S. mutans, and also had high volume of Ca and P ion that protected teeth. So I suggest that they have positive effect on teeth.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.150-158
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• 2015

This article reports the development of an effective test procedure for detection of norovirus (NoV) in foods of diverse matrices. In this study, target foods included fermented milk, soybean paste, powders made from uncooked grains and vegetables, sesame leaves preserved in soy sauce, pickled mooli, and mooli. Viral recovery varied depending on the food matrices or elution buffers tested. Buffers were compared to determine effective elution buffers from artificially virus-contaminated foods. The conventional test procedure for concentrating viruses from food (elution-polyethylene glycol(PEG) precipitation-chloroform-PEG precipitation) was modified to save time by eliminating one PEG precipitation step. The modified procedure (elution-chloroform-PEG precipitation) was able to concentrate viruses more effectively than the conventional procedure. It also removed RT-PCR inhibitors effectively. The modified procedure was applied to target food for genogroup II NoV detection. NoV RNA was detected at the initial inoculum levels 3.125-12.5 RT-PCR units per 10-25 g tested food. The use of this newly established procedure should facilitate detection of low levels of norovirus in diverse foods.

• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.340-344
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• 1993

Gel type yoghurts from 5 representative manufacturers were collected at market and evaluated their physico-chemical properties during storage at $5^{\circ}C$. The range of pH, acidity, Brix and viscosity of each product were $3.87{\sim}4.19,\;0.97{\sim}1.42%,\;16.2{\sim}22.2\;and\;7,850{\sim}21,000 cp$ respectively. The pH of each product decreased gradually during storage time and reached around pH 4.1 after 16 days with proportional acidity increasing. The viscosity of all test products showed increasing trend by lactic acid bacterial action. Total lactic acid bacteria were $10^8{\sim}10^9\;CFU/ml$ at the beginning storage and increased or decreased depending upon each product. But all product maintained over than $10^8 CFU/ml$ which meets regulatory level after 16 days storage.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.781-786
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• 2013

Nutrients fortified dairy products declare their contents on the label for nutrition claim and marketing. However, there are few monitoring studies about relations between actual quantities of fortified nutrients and the described ones on the label. This study was carried out for comparing actual fortified nutrient contents with labeled ones. Forty calcium fortified dairy products and twenty four fructooligosaccharides (FOS) fortified dairy products were sampled at supermarkets located in Anyang, Korea from March to November in 2010. Calcium contents were analyzed by using inductively coupled plasma optical emission spectrometry followed by microwave sample digestion, and FOS contents were analyzed by HPLC-ELSD followed by solvent extraction. In fresh milk, calcium contents ranged from 1.0 to 2.4 mg/mL, and those values were 87~127% of their labeled contents. In fermented milk products and cheeses, calcium contents ranged from 0.3 to 1.6 mg/g (89~131% of their labeled contents), 4.2 to 23.0 mg/g (83~127% of their labeled contents), respectively. FOS contents ranged from 9.09 to 18.89 mg/g in FOS contents labeled products and showed 83~154% compared to their labeled quantity, and ranged from 1.3~30.8 mg/g in products without quantity labeling. In conclusion, the amounts of calcium and FOS in dairy products were above 80% compared to their labeled ones and conformed to the Korean official livestock products labeling standard.