• Applied Biological Chemistry
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• v.39 no.6
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• pp.449-454
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• 1996

We investigated the optimal condition for the production of extracellular pretense(a cuticle-degrading pretense) from entomopathogenic fungus Beauveria bassiana(ATCC7159) in liquid medium by adding of gelatin, bovine serum albumin(BSA), casein and polypeptone. The optimal induction medium for production of extracellular pretenses is composed of 0.5% polypeptone, trace elements and 50 mM potassium phosphate(pH 6.0). In this condition, the production of extracellular pretenses increased rapidly after the 24hrs, peaking at the third day and there was little inductive effect in culture broth more than pH 7.0. The pretenses were inhibited by phenyl methyl sulfonyl fluoride(PMSF). High activity of pretense was showed both range of pH 8.5 and 11.5 and also detected by three different portions of slice gel derived from non-denaturing isoelectricfocusing gel. At least three different extracellular pretenses are produced in optimal production medium when polypeptone is used as the sole carbon and nitrogen source.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.9
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• pp.1332-1338
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• 2003

This study was undertaken to examine the influence of soluble non-starch polysaccharides on growth performance, mucin secretion, and endogenous amino acid flows in weaner pigs. Different levels (0, 4 and 7.5%) of purified corn arabinoxylan (AX) or barley $\beta$-glucan extract (BG) were substituted for cellulose in a purified diet based on starch, sucrose and enzymatically hydrolyzed casein. All diets contained titanium oxide as an indigestible marker. Each experimental diet was fed to five, 6-wk old weaner pigs for 21 days. Average daily gain (p<0.05) and feed conversion ratio (p<0.01) were improved with dietary inclusion of 7.5% AX and BG, indicating high degradation rates of AX and BG in pigs. Crude mucin contents and endogenous nitrogen flow were increased (p<0.05) with increased levels of AX, but not with BG. Numerical increases in endogenous amino acid flow (EAAF) were observed with increased levels of AX but no definite trend with BG. Endogenous amino acid flow in pigs fed mixed NSP diets (4% BG and 3.5% cellulose) was significantly higher (p<0.05) than those fed 7.5% BG diets. Among diets containing pure sources of soluble non-starch polysaccharides, endogenous amino acid flows were highest in 7.5% AX (p<0.05), intermediate in BG, and lowest in control diet. Increased flows (p<0.01) of threonine, proline and serine in pigs fed 7.5% AX diets are consistent with the increased flow of crude mucin determined in this treatment. In conclusion, mucin and endogenous amino acid flows were increased with dietary inclusion of AX, which could be related to its physicochemical property, particularly its high water-holding capacity. In contrast, $\beta$-glucan, due to its high degradation rate in pig, may be considered as unimportant factor in inducing mucin and endogenous amino acid secretions, at least at levels such as those used in this study.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1634-1641
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• 2005

Generally, dietary fibre (DF) includes lignin, non-starch polysaccharides (NSP) and resistant starch (RS). In monogastric species, low levels of dietary fibre in the diet are associated with various diseases and high levels reduce nutrient digestibilities. In this study, the effects of different types and levels of NSP (soluble: $\beta$-glucan, insoluble cellulose) and resistant starch on mucin secretion and endogenous nitrogen and amino acid losses in pigs were investigated. A total of 25 five-week-old weaner pigs (9.5 kg${\pm}$1.5 kg), were randomly allocated to each of five experimental diets. Different levels of purified barley $\beta$-glucan (BG) extract (5 or 10% of $Glucagel^{(R)}$ $\beta$-glucan, providing 4 or 8% of BG in the diet), and resistant starch (RS) (8.3 or 16.6% of Hi-$Maize^{TM}$, providing 5 or 10% RS in the diet) were substituted for wheat starch in a purified diet in which enzymatically-hydrolysed casein was the sole source of protein. The diets were fed for 21 days. No statistically significant difference between treatments (p>0.05) was observed for growth performance and organs weights. No difference in ileal starch digestibility was observed between pigs on the cellulose or $\beta$-glucan diets. However, as the level of resistant starch in the diet increased the ileal starch digestibility decreased (p<0.05). The inclusion of resistant starch in the diet (5 or 10%) did not increase mucin production when compared with the cellulose-only diet. However, as the level of beta-glucan in the diet increased, both crude mucin in the digesta dry matter and per kg dry matter intake increased (p<0.05). Pigs fed the diet containing 8% of beta-glucan had higher endogenous loss flow than those fed the diets including 5 or 10% of resistant starch or 4% of $\beta$-glucan. In conclusion, dietary inclusion of resistant starch increased the level of starch reaching the large intestine without any effect on mucin secretion, or endogenous nitrogen or amino acid losses content in the small intestine. The addition of $\beta$-glucan to a diet containing cellulose increases both mucin secretion and endogenous amino acid and nitrogen losses in the small intestine.

• Korean Journal of Agricultural Science
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• v.13 no.2
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• pp.198-209
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• 1986

This study was conducted to find optimum heating temperature and time as milk was heated over a wide range of temperature and time combinations at $70{\sim}100^{\circ}C$ into $5^{\circ}C$ interval for 10, 15 and 20 second. The results obtained were summarized follows: 1. The effects of heat treatment on the bacteria by $75^{\circ}C/20s$, $80^{\circ}C/10s$ and $100^{\circ}C/20s$ were 99.56%, 99.52% and 99.92% respectively. 2. Sterilized rate of milk which was added Bacillus subtilis by $75^{\circ}C/20s$, $80^{\circ}C/10s$ and $100^{\circ}C/20s$ were 99.23%, 99.25% and 99.85% respectively. 3. The pH value fell in accordance with the increasing of heating temperature. 4. Content of protein, fat and lactose was not changed by heat treatment. 5. The content of total nitrogen was not changed. The content of casein nitrogen and non - protein nitrogen increased, but non - casein nitrogen reduced, according to heat trea ted of milk. 6. According to the increasing of heating and time, filter - passing nitrogen reduced. 7. The artificial digestibility was increased when milk was heated from $70^{\circ}C$ to $100^{\circ}C$ into $5^{\circ}C$ interval at 10, 15 and 20 second.

• Korean Journal of Food Science and Technology
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• v.52 no.6
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• pp.610-615
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• 2020

Edible insects might be used as a means to solve food insecurity caused by population growth. Many studies have investigated the biological activity of insects; however, few studies have investigated the nutritional value of insects. Therefore, the aim of this study was to investigate the nutritional value of Allomyrina dichotoma larva protein (ADP) as a source of protein replacement. In vivo studies were conducted to determine the food efficiency ratio (FER), protein efficiency ratio (PER), and true digestibility (TD) of ADP. Experiments were conducted in 3 groups of 8 animals per group using twenty-four 4-week-old SD rats. The experimental groups included the general diet group (Con), in which 20% of the total Kcal in the diet was composed of casein protein, and the ADP group (ADP), in which 20% of the total Kcal was composed of ADP protein, and a non-protein diet group (NP) to measure the protein (metabolic fecal nitrogen) excreted by metabolic processes in the body. As a result of this experiment, we found that the FERs were 0.52 and 0.41 in the casein protein intake (Con) and ADP groups, respectively, thus showing a significantly lower level in the ADP group. The PERs of ADP and Con were 2.39 and 2.63, respectively. The TD of Con and ADP were 91% and 80%, respectively.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.352-360
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• 2010

This study was performed to develop a Korean natural cheese with traditional medical wine, making it different from foreign natural cheese. The effects of cheese with Sasam(Codonopsis lanceolate) wine(CLW) on the quality properties during the ripening period of natural cheese were investigated. The properties investigated were growth of lactic acid bacteria, characteristics of ripening, and sensory characteristics. Four vats of cheese were made on the same day from the same tank of fresh milk. Cheese samples were prepared with CLW at 2.0%, 4.0% and 6.0% of raw milk. Changes in gross composition, viable cell counts, pH, water soluble nitrogen(WSN), non casein nitrogen(NCN), non protein nitrogen(NPN), and proteolysis during maturation were measured. Polyacrylamide gel electrophoresis(PAGE) patterns were determined with control cheese. Viable cell counts of control and CLW cheese were not significantly different. The pH of CLW cheese increased gradually during maturation, and saponin levels and levels of NPN, NCN, and WSN were higher in CLW cheeses than control cheese. For most compositional data, the 4.0% CLW cheese was most similar to the control cheese. The PAGE pattern of cheese caseins indicated that the CLW cheeses degraded more rapidly than the control cheese. Control and 2.0% CLW cheese had good sensory scores, while scores for 4.0% and 6.0% CLW cheese were lower. However, sensory data depreciated with added levels of CLW, especially at a level of 4.0% or more. Further studies on levels of CLW and processing methods are required to improve sensory quality.

• Food Science of Animal Resources
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• v.30 no.1
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• pp.102-109
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• 2010

Imitated cheese was prepared from whole milk powder and fermented milk and the moisture content, general components, noncasein nitrogen, nonprotein nitrogen and free amino acids were analyzed to determine the optimal ripening conditions needed to produce imitated cheese that was similar to natural cheese. The moisture content of the imitated cheese was 40.27% one day after being produced. The cheese was ripened using two different methods; at $12^{\circ}C$ with vacuum sealing and at $12^{\circ}C$ and 95% RH with a spray of Penicillium camemberti. The lactose content decreased rapidly from 24.64 to 5.43% at the $4^{th}$ wk of ripening when it was ripened with Penicillium camemberti. The degradation of protein by mold ripening in the imitated cheese was more rapid than that of vacuum sealing. The flavor and body texture were optimal at the $4^{th}$ wk ripening. The noncasein nitrogen and nonprotein nitrogen content increased from 28.10 to 54.05, and from 6.58 to 23.06 mg/mL, respectively, when ripened with P. camemberti. When the cheese was ripened at $12^{\circ}C$, 95% R.H with P. camemberti after 4 wks, all free amino acids increased significantly except asparagines. The total free amino acid and bitter amino acid concentrations increased from 8.40 to 34.87, and from 1.53 to 10.02 nmol/mg, respectively. When the imitated cheese was prepared, the protein degradation and flavor of the cheese was better when ripened with P. camemberti.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.332-337
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• 1994

Under standard condition (Han, et al., 1990: glucose 1%-nitrate 0.1% minimal medium, 30 ml in 9 cm plate, $10^6$ cells of inoculum per plate), wild type of Aspergillus nidulans developed both sexual and asexual organs in ballance, while velA1 mutant developed asexual ones preferentially. Increase of glucose concentration did not significantly affect the asexual sporulation. However, development of sexual organs were largely affected. It was greatly enhanced when favorable nitrogen source, for example, casein hydrolysate was added, which is contrary to the case of Neurospora or Saccharomyces where limitation of N source induces sexual development. On most of moderate C sources asexual development in $velA^+$ strain was largely inhibited except acetate on which only asexual spores were produced, while that in velA1 mutant strain was not affected. Lactose promoted the sexual development even in velA1 mutant indicating that lactose itself or its metabolic intermediate may induce sexual development independent of allelic state of velA gene. On other moderate favorable C sources, glycerol, galactose and ethanol, asexual development was largely inhibited in $velA^+$ strain but not in velA1 mutant strain. Sexual organs were, however, never produced on acetate. These results suggested that asexual development of wild type is largely dependent on C sources and the velA gene is involved in the repression of asexual development in not-enough-grown (non-competent) thalli resulting in preferential progression of sexual development.

• Journal of Dairy Science and Biotechnology
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• v.31 no.1
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• pp.21-33
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• 2013

The purpose of this study was to improve the production of Mozzarella cheese analogues manufactured using mixtures of soy milk and concentrated raw milk by performing ultrafiltration (UF) and to assess the quality of these cheeses during a 30-day storage period at $4^{\circ}C$, relative to that of Mozzarella cheese manufactured with the traditional method. The solid consistency of Mozzarella cheese analogue prepared from milk mixtures was lower than that of cheese manufactured from raw milk or soy milk and increased during storage, which is considered to be the result of decreasing water levels, as well as with increasing soy milk concentrations. In the Mozzarella cheese analogue generated using the milk mixtures, the fat content decreased with increase in the soy milk concentration, while it decreased during the storage period. Lactose levels were lowest in cheese composed of soy milk or raw milk and processed by UF, and decreased during storage in cheese produced using milk mixtures. In milk mixtures containing soy milk, the protein concentration increased with increasing amounts of raw milk and did not change during the storage period. The water-soluble nitrogen compound level was similar between cheeses and increased only slightly during storage. The amount of non-protein nitrogen compounds was higher in the cheese analogue than in the control cheese and tended to increase during storage. Analysis of the physicochemical traits of the Mozzarella cheese analogue yielded the following results: During storage, titratable acidity levels increased while pH tended to decrease. After analysis using electropherograms, it was classified as ${\alpha}$-, ${\beta}$-, or ${\kappa}$-casein. The results of rheometry tests showed that in the Mozzarella cheese analogue prepared from milk mixtures, with raw milk concentrated by UF, increases in concentration rate lead to lowered hardness, elasticity, cohesiveness, and brittleness. When cheese was produced from milk mixtures and concentrated by UF, meltability increased as the concentration rate increased, although to an extent that was less than that observed for the control cheese, and tended to increase during storage. Sensory evaluation showed that the analogue cheese was much better than the control cheese in terms of formation, appearance, and flavor.

• Food Science of Animal Resources
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• v.26 no.4
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• pp.525-531
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• 2006

Effects of Chlorella powder on the growth of lactic acid bacteria, ripening velocity and organoleptic properties in Appenzeller cheese were investigated. Added levels of Chlorella powder were 0, 0.5, 1.0 and 2.0%. The lactic acid bacteria count was higher in cheese added with Chlorella than those in the control cheese. The pH of cheese increased gradually after 3 weeks, reaching pH $5.4{\sim}6.2$ at 15 weeks of maturation, and the pH was slightly lower in Chlorella added cheese than in control cheese. The soluble nitrogen compounds, non casein nitrogen (NCN) and non protein nitrogen (NPN), in Appenzeller cheese increased during 15 weeks of ripening, and they were higher in Chlorella added cheese than in control cheese. Electrophoresis of cheese proteins revealed that caseins were degraded more rapidly in Chlorella cheese as the level of Chlorella increased so that the cheese with 2% Chlorella could have developed a bitter taste and a stench by an excessive degradation of proteins. Sensory scores of the cheese ripened for 15 weeks were diminished as the level of Chlorella increased especially the cheese added with 2% Chlorella obtained significantly lower values of sensory scores than control cheese. Among the Chlorella cheeses, 0.5% Chlorella added cheese showed the highest score in overall sensory preference. From the results, the adequate level of Chlorella powder being added to produce an Appenzeller cheese product with acceptable quality was suggested to be 0.5%.