• Food Science of Animal Resources
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• v.27 no.1
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• pp.29-34
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• 2007

We investigated the properties of pork jerky prepared under various drying conditions. Drying conditions were control ($80^{\circ}C$/210 min), T1 ($55^{\circ}C/60 min\to65^{\circ}C/60 min\to72^{\circ}C/90 min$), and T2 ($72^{\circ}C/90 min\to65^{\circ}C/60 min\to55^{\circ}C/60 min$), respectively. Water content and water activity ($a_w$) were the lowest in control, while TBA values were the highest among all groups (p<0.05). CIE $L^*$-value in T1 was significantly (p<0.05) lower than in T2 and CIE $a^*$-value showed significantly (p<0.05) the highest in control. CIE $b^*$-value in T2 were significantly higher (p<0.05) compared to the other treatments. Drying yields of pork jerky showed the lowest values in controls but highest in T2 jerky. In textual profile evaluations, control samples had greater hardness, cohesiveness, gumminess, and chewiness values than the other treatments, but springiness values were the lowest (p<0.05). Controls had significantly (p<0.05) lower scores than the other treatments in all sensorial traits. Total bacterial counts in T2 were the lowest during drying process. Based on our findings, we conclude that T2 conditions provided the most effective drying process.

• Food Science and Preservation
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• v.8 no.4
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• pp.427-433
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• 2001

The purpose of this study was to investigate the effect of chitosan on the shelf-life and quality of Paeksulkis(Korea rice cake). Paeksulgis containing 0-0.5% chitosan were stored at 5$^{\circ}C$ for 4 week and 2$0^{\circ}C$ for 1 week to test the effect of extenting shelf-life of Paeksulgis by chitosan. The pH of Paeksulkis was 5.65 without chitosan and pH of those were about 7.0(6.94-7.01) with 0.05-0.5% level of chitosan. Moisture content of Paekrukis wish or without chitosan was 38-40%. In Hunter’s color values of Paeksulkis of control, the lightness (L) was 84.28, redness(a) was -1.56 and yellowness(b) was 7.68. The lightness (L), redness(a) and yellowness(b) of Paeksulkis were increased by the increasing concentration of chitosan. In mechanical characteristics, cohesiveness concentration of Paeksulkis were the highest in control while obtained the highest score in color, after swallowing and overall quality (p<0.05). The score of flavor and consistency of Paeksulkis with different levels of chitosan wre not significant while the score of moisture in Paeksulkis with 0.05-0.5% level of chitosan was significantly higher than control (p<0.05). The score of flavor and consistency of Paeksulkis with different levels of chitosan were not significant while the score of moisture in Paeksulkis with 0.05-0.5% level of chitosan was significantly higher than control (p<0.05). Total bacterial counts (TBC) of Paeksulgis immediately before storage were 4.2$\times$10$^2$CFU/g in control and those containing 0.3-0.5% of chitosan were 0.5-1.0 log cycle lower than control. TBC of Paelsulgis containing chitosan was lower than increased for 2 weeks, reached at 1.8$\times$10$^{5}$ CFU/g and decreased for 2 weeks, reached at 1.8$\times$10$^4$CFU/g during storage at 5$^{\circ}C$. TBC of Paeksulkis with more than 0.3% of chitosan were 1.9 log cycles lower than that of control during storage at 5$^{\circ}C$. TBC of Paeksulkis with more than 0.3% of chitosan were 1.9 log cycles lower than that of control during storage at 5$^{\circ}C$ for 4 weeks. TBC of Paeksulgis increased to 10$^{8}$ CFU/g in control and 10$^{6}$-10$^{7}$ CFU/g in more than 0.3% chitosan during storage at 20$^{\circ}C$ for 1 week. The shelf-life of Paeksulkis was increased with increasing concentration of chitosan both temperature at 5$^{\circ}C$ and 20$^{\circ}C$.

• Korean Journal of Poultry Science
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• v.32 no.4
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• pp.281-289
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• 2005

This study investigated the effect of dried food-waste diets(FW) fermented by Aspergillus oryzae(AO), on broiler growth performance, $NH_3$, emission and fecal microflora. Three hundreds broilers, two week old Hubbard strain, were randomly allotted to 4 experiments and fed with standards early boiler diet replaced with FW and AFW. In experiment 1, eighty four broilers were distributed into 7 treatments with 4 pens at 3 birds per replicate(pen). The dietary treatments ; T1 was com-soy bean meal based broiler diet(Control), T2, T3, T4 were for basal diet replaced with dried food waste without AO(FW) at the level of 20, 40 and $60\%$, respectively and T5, T6 and T7 followed the same levels for the basal diet but using Aspergillus oryzae inoculate food-waste(AFW). For experiments 2, 3, 4, seventy two broilers were distributed into 6 treatments with 4 pens at 3 birds per replicate(pen), respectively. The dietary treatments were the com-soy bean meal based broiler diet replacement with different combinations of FW and AFW, 1:0, 3:1, 1:1, 1:3, 0:1. at level of 20, 40 and $60\%$, respectively. In Exp. 1, it tended to be decreased in weight gain, however, there were no statistical differences among treatments except FW $60\%$ level of replacement(p<0.05). Feed intake and feed efficiency was not different among treatments. Total bacterial counts were not different between the control and FW diet, but E. coli decreased as the AFW levels of replacement were increased(p<0.05). There were no differences in weight gain, feed intake and feed efficiency among treatments in Exp. 2 and weight gains were lower fur FW diet compared with the control and AFW diet in Exp. 3(p<0.05). In Exp. 4, there were no differences in feed intakes among treatments, but lower in weight gain and feed efficiency in FW diet than that the control. In experiment 3, the $NH_3$ emission was the highest among treatments in FW/AFW 1:0 diet(p<0.05). From these results, it seems that FW would be supplemented up to $20\%$ in broiler diets and AO culture extract could improve FW value as feed supplements.

• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.244-255
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• 2018

Natural extract in liquid phase was adjusted to 0, 0.25, 0.5, 1, 2, and 4% concentration to check microbial changes and to measure 4, 8, $12^{\circ}C$ for refrigeration temperature. In the case of grapefruit extract, the microbial safety was maintained at all the concentrations at $4^{\circ}C$ storage, but the antimicrobial activity was maintained at $12^{\circ}C$ storage and at $8^{\circ}C$ and 21 days storage. In the case of grape seed extract, only the 4% of the culture at $8^{\circ}C$ satisfied the requirement of safety of food distribution for the last 21 days, and the safety criterion was satisfied only at 4% concentration at $12^{\circ}C$ for 18 days. Complex Scutellaria baicalensis extract showed the total number of microbial cells treated by concentration. It was confirmed that microbial flow safety was maintained at low temperature ($4^{\circ}C$). However, at $8^{\circ}C$ and $12^{\circ}C$, Exceeded the distribution limit. When polylysine was applied to brown rice cake, it showed activity in all groups except $4^{\circ}C$, but these properties were not observed at $8^{\circ}C$ and $12^{\circ}C$. At a concentration of 0.5% or more of chitosan, the growth of the microorganism is suppressed by the 21st day very stably, and a similar tendency is observed at 8 and $12^{\circ}C$, so that it may be an antimicrobial material that inhibits microorganisms. At the first day, the distribution standards for general bacterial counts were exceeded.Ethyl-pyruvate showed that microorganism safety was maintained at $4^{\circ}C$ and 1% concentration, and food safety was stable even at 2 or 4%. Glycine showed very good and stable distribution stability at $4^{\circ}C$. However, at $8^{\circ}C$ and $12^{\circ}C$, the shelf life of 14 days could not be maintained as with the addition of other antimicrobial active substances.

• Journal of Food Hygiene and Safety
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• v.34 no.1
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• pp.94-99
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• 2019

The objective of this study is to establish the shelf life of non-pasteurized whole egg, egg yolk and egg white liquid. Each sample was stored for two weeks at $5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, and $25^{\circ}C$, and then sensory, microbial, and physicochemical tests were performed periodically. The estimation of shelf life was based on the microbial standards of total viable counts and coliforms. The chemical properties highly correlated with the sensory evaluation were also used. Our results showed that the shelf life was the most influenced by microbial properties. Exceptionally, however, whole egg and white liquid stored at $5^{\circ}C$ and $10^{\circ}C$ with limited bacterial growth were affected by chemical property. The shelf life of the three non-pasteurized liquids was calculated to be less than one day at over $15^{\circ}C$. At $5^{\circ}C$ and $10^{\circ}C$, the shelf life was calculated to be 5 d and 1 d for egg yolk liquid, 5 d and 5 d for egg white, and 7 d and 5 d for whole egg, respectively. Therefore, it is advisable to establish reasonable shelf life in the more specific manner based on consideration of these findings.

• Journal of Preventive Medicine and Public Health
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• v.7 no.1
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• pp.1-28
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• 1974

The writers have conducted the investigation to assess the nutritional status of young rural Korean children aged from 0 to 4 years old in August 1971. The survey areas were Kaejong-myon. Daeya-myon, Okku-gun, Jeonra-bukdo, Korea. These survey areas were typical agricultural plain areas. The total numbers of children examined were 2,706 comprising 1,394 male and 1,312 female. The weight, height, and chest circumference of children were measured and means and standard deviations. were calculated for each measurement. In addition, the nutritional status of each child was classified by the four levels of malnutrition and the Gomez classification, The examination of red blood cell count, haematocrit value, and intestinal parasite infection were carried out at the same time. In general, recent work tend to suggest that environmental influences, especially nutrition, are of great importance than genetic background or other biological factors for physical growth and development. Certainly the physical dimensions of the body are much influenced by nutrition, particularly in the rapidly growing period of early childhood. Selected body measurements can therefore give valuable information concerning protein-calory malnutrition. Growth can also be affected by bacterial, viral, and parasitic infection. For the field workers in a developing country, therefore, nutritional anthropometry appears to be of greatest value in the assessment of growth failure and undernutrition, principally from lack of protein and calories. In order to compare and evaluate the data obtained, the optimal data of growth from the off-spring of the true well-fed, medically and socially protected are needed. So-called 'Standards' that have been compiled for preschool children in Korea, however, are based on measurement of children from middle or lower socio-economic groups, who are, in fact, usually undernourished from six months of age onwards and continuously exposed to a succession of infective and parasitic diseases. So that, the Harvard Standards which is one of the international reference standards was used as the reference standards in this study. Findings of the survey were as follows: A. Anthropometric data: 1) Comparing the mean values for body weight obtained with the Korean standard weight of the same age, the rural Korean children were slightly haevier than the Korean standard values in both sexes. Comparing with the Japanese children values, the rural Korean children were slightly haevier in male and in the infant period of female but lighter in female of the period of 1 to 4 years old than Japanese children. 2) Comparing the mean values for height obtained with the Korean standard height of the same age, the rural Korean children were taller than the Korean standard values except the second half of infatn period in both sexes. Comparing with the Japanese children, the rural Korean children were slightly smaller than Japanese children except the first half of infant peroid in both sexes. 3) Mear values of chest circumference of rural Korean children obtained were less than the Korean standard values of the same ages in both sexes. B. Prevalence of Protein-Calory Malnutrition: Children examined were devided into two groups, i. e., infant(up to the first birthday) and toddler (1 to 4 fears old). 1) Percentages of four levels of malnutrition: a) When the nutrtional status of each child was classified (1) by body weight value, the percentages for male and female of children attained standard growth were 52.8%(infant 83.3%, toddler 44.4%) and 39.7% (infant 74.5%. toddler 30.5%), the first level of malnutrition were 31.9%(infant 13.7%, toddler 36.9%) and 31.7%(infant 15.3%, toddler 36,0%), the second level of malnutrition were 12.3%(infant 1.7%, toddler 15.3%) and 23.3% (infant 7.7%, fodder 27.5%), the third level of malnutrition were 2.7%(infant 0.7%, toddler 3.2%) and 4.6%(infant 1.8%, toddler 5.3%) the fourth level of malnutrition were 0.3% (infant 0.7%, toddler 0.2%) and 0.7% (0.7% for infant and toddler) respectively. (2) by height value, the percentages for male and female of children attained standard growth were 80.3% (infant 97.3%, toddler 75.6%) and 75.1% (infant 96.4%, toddler 69.5), the first level of malnutrition were 17.9% (infant 2.0%, toddler 22.3%) and 23.6% (infants 3.6%, toddler 28.8%), the second level of malnutrition were 1.2% (infant 0.3%, toddler 1.5%) and 1.1% (infant 0%, toddler 1.4%), the third level of malnutrition were 0.4%(infant 0.3%, toddler 0.5%) and 0.2%(infant 0%, toddler 0.3%), the fourth level of malnutrition were 0.1%(infant 0%, toddler 0.1%) and 0% respectively. (3) by body weight in relation to height, the percentages for male and female of children attained standard growth were 87.9% (infant 77.6%, toddler 87.9%) and 78.2% (infant 77.4%, toddler 78.2%), the first level of malnutrition were 12.2% (infant 18.4%, toddler 10.6%) and 18.2% (infant 17.9%, toddler 18.3%), the second level of malnutrition were 1.9%(infant 3.3%, toddler 1.5%) and 3.0%(infant 3.3%, toddler 2.9%), the third level of malnutrition were 0.1%(infant 0%. toddler 0.1%) and 0.5% (infant 0%, toddler 0.6%), the fourth level of malnutrition were 0.1%(infant 0.7%, toddler 0%) and 0.3% (infant 1.5%, toddler 0%) respectively. b) When the nutritional status of each child according to the mother's age at perturition, i. e., young aged mother (up to 30 years old), middle aged mother (31 to 40 years old) and old aged mother (41 years or above) was classified (1) by body weight, among infants and toddlers, at each year of age, with increasing the mother's age, there was an increase in percentage of subjects underweight. This tendency of increasing percentage of underweight was more significant in the infant period than the toddler period. (2) by height value, no significant differences between each mother's age group were found. c) When the nutritional status of each child according to the birth rank, i. e., lower birth rank (first to third) and higher birth rank (fourth or above) was classified (1) by weight value, children of higher birth rank were slightly more often underweight than those of lower birth rank, but not significant. (2) by height value, no differences were found between children of lower and higher birth rank. 2) Gomez Classification: When the nutritional status of each child was classified a) by body weight value, the percentages for male and female of children. attained standard growth were 53.1% (infant 82.6%, toddler 44.9%) and 39.2% (infant 73.4%, toddler 30.1%), the first degree of malnutrition were 39.4% (infant 14.7%, toddler 46.2%) and 47.1% (infant 21.9%, toddler 53.8%), the second degree of malnutrition were 7.3%(infant 2.3%, toddler 8.6%) and 12.9% (infant 4.0%, toddler 15.2%). and the third degree of malnutrition were 0.2%. (infant 0.3%, toddler 0.2%) and 0.8% (infant 0.7%, toddler 0.9%) respectively. b) by height value, the percentages for male and female of children attained standard growth were 80.8% (infant 97.0%, toddler 76.3%) and 73.8%(infant 95.6%, toddler 68.0%), the first degree of malnutrition were 18.5% (infant 2.7%, toddler 22.9%) and 24.6% (infant 4.4%, toddler 30.0%), the second degree of malnutrition were 0.6%(infant 0.3%, toddler 0.7%) and 0.5% (infant 0.1%, toddler 0.7%), and the third degree of malnutrition were 0.1%(infant 0%, toddler 0.1%) and 1.1% (infant 0%, toddler 1.3%) respectively. C. Results of clinical laboratory examination: 1) Red blood cells: The ranges of mean red blood cell counts for male and female were $3,538,000/mm^3\;to\;4,403,000/mm^3\;and\;3,576,000/mm^3\;to\;4,483,000/mm^3$ respectively. The lowest red cell counts were seen at the age of 0-3 months for male and 1-2 months for female. 2) Haematocrit value : The ranges of haematocrit value of male and female were 35.1% to 38.8% and 34.7% to 38.8% respectively. The lowest haematocrit values were seen at the age of 2-3 months for male and 1-2, months for female. 3) The prevalence rates of intestinal parasites for male and female children with Ascaris lumbricoides were 34.1% (infant 18.8%, toddler 38.1%) and 36.0%(infant 18.4%, toddler 40.7%), with Trichocephalus trichiuris were 6.8% (infant 2.9%, toddler 7.9%) and 9.0% (infant 3.0%, toddler 10.6%), with Hookworm were 0.3% (infant 0.5%, toddler 0.2%) and 0.3% (infant 0.5%, toddler 0.3%), with Clonorchis sinensis were 0.4%(infant 0%, toddler 0.5%) and 0.1%(infant 0%, toddler 0.1%) respectively.