• Journal of Dairy Science and Biotechnology
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• 제39권1호
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• pp.9-19
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• 2021

Enterobacter sakazakii (Cronobacter spp.) causes meningitis, necrotizing enterocolitis, sepsis, and bacteremia in neonates and children and has a high mortality rate. For rapid E. sakazakii detection, various differential and selective media containing α-glucosidase substrates, such as 5-bromo-4-chloro-3-indolyl-α-D-glucopyranoside (BCIG) or 4-methylumbelliferyl-α-D-glucoside (α-MUG), have been developed as only E. sakazakii exhibits α-glucosidase activity in the genus Enterobacter. However, Escherichia vulneris (family: Enterobacteriaceae) can also utilize α-glucosidase substrates, thereby resulting in false positives. Various iron sources are known to promote the growth of gram-negative bacteria. This study aimed to develop a selective medium containing α-glucosidase substrates for E. sakazakii detection that would eliminate false positives, such as those of E. vulneris, and to determine the role of iron source in the medium. Three previously developed (TPD) media, i.e., Oxoid, OK, and VRBG, and the medium developed in this study, i.e., NGTE, were evaluated using 58 E. sakazakii and 5 non-E. sakazakii strains. Fifty-four E. sakazakii strains appeared as fluorescent or chromogenic colonies on all four media that were assessed. Two strains showed colonies on NGTE medium and not on TPD media. In contrast, the remaining two strains showed colonies on TPD media and not on NGTE medium. None of the non-E. sakazakii strains showed fluorescent or chromogenic colonies on any of the evaluated media except E. vulneris, which showed colonies on TPD media and not on NGTE medium. This study demonstrated that the newly developed NGTE medium was not only equally efficient in promoting the growth of bacterial colonies when compared with the currently available media but also eliminated false positives, such as E. vulneris.

• Journal of Dairy Science and Biotechnology
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• 제40권3호
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• pp.122-133
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• 2022

Radish (Raphanus sativus L.) has long been recognized as a source of nutrients and phytochemicals. It is well known that the antioxidant properties of radish contributed to its popularity in pharmaceuticals. For this reason, the radish extract aided in the recovery and prevention from diseases. Hence, in this study, the sensory evaluation assessment was conducted following addition of radish oil to almond milk, oat milk, and soy milk (nondairy products) and Kefir, yogurt, and cow milk (dairy products) at different concentrations (containing 0.5% increments from 0% up to 2%). According to the results obtained in this study, all samples containing 0.5% radish oil scored higher on the sensory evaluation scale than the control. It is also very valuable as it is the first study to investigate sensory evaluation assessment by incorporating radish oil into almond milk, oat milk, and soy milk (nondairy products) and kefir, yogurt, and cow milk (dairy products). Furthermore, the results of this study can be used as a foundation for developing future products using radish oil. Additional research on addition of plant-based essential oil to various foods should be conducted.

• Journal of Dairy Science and Biotechnology
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• 제40권2호
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• pp.66-75
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• 2022

Aloe vera has several beneficial health effects as it interacts with probiotics and is also a source of prebiotics, antioxidants, and other bioactive materials. Thus, there has been increasing interest in the development of beverages containing Aloe vera. In this investigation, sensory qualities were estimated by fortifying oil isolated from Aloe vera in non-dairy and dairy products at different concentrations (fortified with 1% increments from 0% to 5%). Because of the strong aroma and strong yellow color of aloe oil, the sensory quality values estimated in this study were generally low. However, the samples fortified with 1% aloe oil exhibited the best sensory quality values compared with the control. Consequently, the results of this study are valuable as preliminary findings to determine the various sensory qualities of kefir fortified with aloe oil. To improve sensory qualities in the future, it is necessary to estimate the optimal lowering of the concentration of fortified aloe oil, and assess whether aloe oil exhibits various biofunctional activities at different concentrations.

• Journal of Dairy Science and Biotechnology
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• 제40권2호
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• pp.76-85
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• 2022

Broccoli sprouts are an excellent source of health-promoting phytochemicals, such as glucosinolates, phenols, and vitamins. In this investigation, oil extracted from broccoli was adjusted to various concentrations (control, 1%, 2%, 3%, 4%, and 5%, respectively) and added directly to dairy products (cow milk, yoghurt, and kefir) and non-dairy products (soy milk), and their organoleptic properties assessed. The results showed that when the amount of broccoli oil was increased, the organoleptic properties (texture, color, and flavor) and overall acceptability tended to decrease. Cow milk, yoghurt, kefir, and soymilk supple-mented with 1% broccoli oil showed the best organoleptic properties when compared to the control group. The fermented products such as yoghurt and kefir with added broccoli oil showed good organoleptic properties. Overall, the results of this study provide evidence for the use of broccoli oil in dairy and non-dairy products. Further research will be required to assess the various physiological active functions of broccoli oil.

• Journal of Dairy Science and Biotechnology
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• 제40권3호
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• pp.110-121
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• 2022

The root of ginger (Zingiber officinale) contains gingerol, which is known to be responsible for its pharmacological activity. The essential oil extracted from ginger has been found to have various pharmacological effects. Thus, interest in the development of various beverages using ginger oil has recently increased. Therefore, in this study, the organoleptic quality assessment of cow milk, yogurt, kefir, soy milk, oat milk, and almond milk was conducted by supplementing them with oil extracted from ginger at various concentrations (supplemented with 0.5% increments from 0% up to 2%). A poor grade was obtained in the organoleptic quality evaluation, owing to the strong odor of ginger oil. However, when compared to that of the control, the samples supplemented with 0.5% ginger oil showed a good grade of organoleptic quality assessment. Therefore, this study is considered valuable as it is the first study to review the organoleptic quality assessment by supplementing milk, yogurt, kefir, soy milk, oat milk, and almond milk with ginger oil. Additionally, in order to improve organoleptic quality assessment, it is critical to estimate how much ginger oil supplementation concentration could be reduced and whether ginger oil exhibits various bio-activities at this concentration.

• Journal of Dairy Science and Biotechnology
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• 제40권4호
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• pp.151-162
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• 2022

Although many developed countries (USA, Canada, and several EU countries) allow raw milk cheese to be aged more than 60 days, these countries have strict standards for the aging conditions, such as temperature, of raw milk cheese. Spiking experiments were conducted with Camembert cheese made from raw milk, to assess the microbiological safety of raw milk cheese aged for more than 60 days. We spiked Escherichia coli O157:H7 into raw milk with different inoculation levels (high, medium, and low). Camembert cheese was prepared from the inoculated raw milk, then aged in an incubator for up to 9 weeks (63 days). There were no significant differences in pH and water activity (aW) between uninoculated cheese and cheese samples inoculated with E. coli O157:H7 (p<0.05). The pH and aWof the Camembert cheese decreased throughout the storage period. In conclusion, E. coli O157:H7 did not affect the pH and aW of the cheese samples. Cell counts were conducted every week using the agar-plating method. Inoculated cells were completely eliminated, especially in Camembert cheese, after 60 days, and the reduction rate of cells was much faster in Camembert cheese.

• Journal of Dairy Science and Biotechnology
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• 제40권4호
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• pp.163-172
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• 2022

Although the USA, Canada, and several EU countries allow raw milk cheese to be aged more than 60 days, these countries have strict standards for its aging conditions, such as temperature. Many developed countries have employed standards of identity which effectively prevent the manufacture and sale, of cheese made from unpasteurized milk (i.e., raw milk) in interstate commerce, unless such cheese has been aged for a minimum of 60 days. The microbiological safety of raw milk Camembert cheese, aged for more than 60 days, was evaluated using spiking experiments. We spiked Listeria monocytogenes into raw milk with different inoculation levels (high, medium and low). Camembert cheese was prepared from the inoculated raw milk, then aged in an incubator for up to 9 weeks (63 days). The number of cells was determined every week using the agar-plating method. Inoculated cells were completely eliminated, especially in Camembert cheese, after 60 days, and the reduction rate of cells was much faster in Camembert cheese. There were no significant differences in pH and water activity (aW) between the uninoculated cheese and the cheese samples in which Listeria monocytogenes was inoculated (p<0.05). The pH and aW of the Camembert cheese decreased throughout the storage period. In conclusion, the pathogenic bacteria used in this study did not affect the pH and aW of the Camembert cheese samples.

• Journal of Dairy Science and Biotechnology
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• 제40권1호
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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.

• 한국동물위생학회지
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• 제45권2호
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• pp.139-143
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• 2022

A 10-year-old, spayed female miniature schnauzer was referred to the Veterinary Medical Teaching Hospital of Chungnam National University due to evaluation of sudden polyuria (PU) and, polydipsia (PD) (540 mL/kg/day) with severe anemia and weight loss. Blood examination results were normal except for severe anemia (hematocrit, [HCT]: 11.8%). Urinalysis revealed a urine specific gravity (USG) of 1.003, whereas urine sediment was not specific. Urine osmolality was 90 mOsm (reference range: 800~2500 mOsm), and plasma osmolality was 303 mOsm. No specific lesions were found using diagnostic imaging including radiography, ultrasonography and magnetic resonance imaging (MRI). The serum cortisol level was normal in cosyntropin stimulation test. Plasma arginine vasopressin (AVP) concentration was <0.4 pg/mL (reference range: 3.49~5.45 pg/mL). Blood transfusion was initiated in addition to an oral prescription of desmopressin acetate (DDAVP, 0.1 mg/head) thrice a day for one week. The patient was rechecked for clinical signs, urine osmolality, and USG; the clinical signs of PU/PD were resolved, urine osmolality increased to 1106 mOsm, and, USG increased to 1.021. Considering the improved clinical signs, and increased urine osmolality, and USG after DDAVP treatment, the dog was diagnosed with central diabetes insipidus. USG and urine osmolality increased to >1.030 and 2200 mOsm, respectively. Anemia also gradually improved and HCT increased to >37%. DDAVP was tapered to 0.1 mg/head twice a day and all clinical signs in the patient have completely resolved.

• Journal of Dairy Science and Biotechnology
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• 제41권1호
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• pp.26-33
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• 2023

Eugenol, which can be extracted from clove oil, is a phenolic aromatic compound and has been found to have antibacterial, antiviral, antifungal, anticancer, anti-inflammatory, and antioxidant functions. Consequently, clove oil has long been used in several fields (food, medicine, skincare). Hence, in this study, the sensory profile of clove oil contained in milk analogs (almond, oat, and soy milks) was evaluated at different amounts (added at 0.25%-0.5% increments from 0% to 1.5%). Because of the strong scent of clove oil, the value of the evaluation for sensory profile determined in this study tended to be low. However, compared with the control group, good values in the evaluation for the sensory profile were found in all samples containing 0.25% of clove oil. We evaluated clove oil contained in milk analogs to help increase their sales through products with improved functionality.