• Animal Bioscience
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• v.36 no.6
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• pp.908-919
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• 2023

Objective: Information about the chemical composition of cassava-based feed ingredients is needed to accurately formulate animal diets. A study was conducted to determine the chemical composition of cassava-based feed ingredients and to test the hypothesis that there is variation in chemical composition among cassava products originating from different South-East Asian countries. Methods: Sources of dried peeled and unpeeled cassava roots, cassava chips, cassava meal, high-ash cassava meal, and cassava residue were used. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid-hydrolyzed ether extract (AEE), ash, minerals, total starch, insoluble dietary fiber, and soluble dietary fiber. Samples of peeled and unpeeled cassava roots, cassava chips, and cassava meal were also analyzed for sugars. Results: High-ash cassava meal had greater (p<0.05) dry matter and ash, but lower (p<0.05) total starch and gross energy than all other cassava products. Peeled cassava roots, unpeeled cassava roots, and cassava chips had greater (p<0.05) total starch than the other cassava-based ingredients. Cassava residue had greater (p<0.05) concentrations of lysine, insoluble dietary fiber, and soluble dietary fiber compared with the other cassava products, but tryptophan and glutamic acid were greater (p<0.05) in peeled cassava roots, cassava chips, and cassava meal samples compared with the other ingredients. Concentration of most minerals was greater (p<0.05) in high-ash cassava meal than in the other cassava products. Conclusion: Cassava-based ingredients sold as peeled roots, unpeeled roots, chips, or meal have chemical compositions that are not different from each other, and peeling has little impact on chemical composition. High-ash cassava meal has lower nutritional quality compared with other cassava products due to low starch and gross energy. The high fiber content in cassava residue makes this ingredient more suitable for ruminants and sows than for younger pigs or poultry.

• Preventive Nutrition and Food Science
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• v.2 no.1
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• pp.11-16
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• 1997

Alkaline cooking and processing properties of domestic maize were evaluated by comparing to those of imported control maize(Asgrow 404). Domestric maize varieties were hydrated more rapidly and had lower dry matter losses during alkaline cooking than control maize due to softer endosperm texture and incomplete removal of pericarps. Domestic maize varieties produced masas with proper handling properties when nixtamals had 50~52% moisture. However, masas produced from domestic maizes were puffed dur-ing baking and frying process due to the release of more free starch granules in the masa than control masa. Tortilla chips prepared from domestic maizes absorbed more oil during frying and had slightly higher water content with darker color than tortilla chips prepared from control maize. Among the domestic maize hybrids, KS42/Fla2BT113 had more acceptable kernel characteristics of tortilla chips than other varieties.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.206-210
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• 2001

Six Holstein$\times$indigenous multiparous dairy cows, $60{\pm}8$ days in milk, were used in a double $3{\times}3$ Latin square design to investigate the efficiency of milk production. The dairy cows were randomly allocated to total mixed rations (TMR) containing ground corn, ground corn plus cassava chips 50:50 and cassava chips as main sources of total non-fiber carbohydrates. Ether extract and calculated energy intakes for dairy cows fed TMR containing cassava chips were lower (p<0.05) than those fed TMR containing ground corn and ground corn plus cassava chips 50:50. There were no differences (p>0.05) in daily DM intake (3.51, 3.41 and 3.29% BW), in 4% fat corrected milk (19.66, 20.59 and 20.23%), in milk protein (3.37, 3.27 and 3.33%), and in solids-not-fat (9.03, 8.90 and 8.99%) but there were differences in cost of diets per kg of 4% fat corrected milk (40.75, 34.33 and 28.17%; p<0.01) for dairy cows fed TMR containing ground corn, ground corn plus cassava chips 50:50, and cassava chips. It can be concluded that the efficiency of milk production (4% fat corrected milk per dry matter intake) for dairy cows fed TMR containing cassava was greater than for those fed TMR containing corn.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.1
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• pp.70-77
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• 2015

This paper develops and evaluates a mechanical machining process which involves drilling on PVS material. According to the material, two treatment experiments were conducted, one involving drilling in a wet condition or using a lubricant and one involving drilling in a dry condition with no lubricant. Drilling in a dry condition showed better performance in terms of the cutting time than in the wet condition. Otherwise, the wet condition has several advantages. The lubricant influenced the burr diameter size and minimized the temperature on the surface of the work piece. During the wet condition drilling process, a smaller burr diameter size was noted as compared to the dry condition. The temperature showed a linear correlation with the drill bit size, where a least-square analysis provided an $R^2$valuewhichexceeded 0.95. The wet condition required more cutting time than the dry condition. In this condition, the water provides a lubrication effect. A thin layer between the cutting edges and the surface of the work piece is formed. The chip formation is affected by the drilling depth. The color on the tips of the chips was darker than in the initial condition. No correlation between the drilling depth and the bore roughness was noted, but the variation of the cutting speed or the RPM influenced the roughness of the bore. The optimum cutting speed ranged from 40 RPM to 45 RPM in the condition which provided the finest roughness surface.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.1
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• pp.68-72
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• 2008

AlGaInP high-brightness LEDs(HB-LEDs) have gained importance a variety of application operating in the red, orange, yellow and yellow-green wavelength. The light generated from inside LED chips should be emitted to the air through the surfaces of the chips. However, because of the differences between the semiconductor and air or epoxy's refractive index, some of the light was blocked so that caused lowering external quantum efficiency. In this study, nano-scale roughness on the top-GaP layer of AlGaInP epitaxial wafer was fabricated to improve' the brightness of AlGaInP LEDs. Nano-scale roughness was made by ICP dry etcher. Our AlGaInP LEDs with nano-scale roughness has higher brightness (about 28.5 %) than standard AlGaInP LEDs.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.153-160
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• 2011

In this study, we have developed taste and other functional enhancements of yam chips, from tasteless and flavorless yam slices, through the process of soaking freeze-dried yam in different commercially available juices, including apple, omija (fruit of Maximowiczia typica), grape, wild grape, orange, tomato, red ginseng, and black garlic juice. The analyses of color (brightness, redness and yellowness), pH, brix, acidity, total polyphenol, total flavonoids, total sugar and reducing sugar, DPPH and ABTS scavenging activity, reducing power and nitrite scavenging activity, of the different yam chips showed that the freeze-dried yam slices absorb various components of fruit juices, such as flavonoids, sugars, organic acids and flavors, during the soaking process. These changes resulted in increased taste (both sweet and sour tastes), flavor and antioxidant activity in the yam chips. The soaking time for yam slices in juice is considered to be a crucial factor for the taste and bioactivity of yam chips. In the case of grape juice-yam chips, which had the highest preference among the 8 different chips, the optimum soaking time was noted as 120 seconds. The optimization of the soaking process is necessary for various juices. These results suggest that taste, and other functional enhancements, in yam chips can be developed by juice-soaking and freeze-drying methods.

• Horticultural Science & Technology
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• v.18 no.1
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• pp.33-38
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• 2000

This study was conducted in an effort to meet the need for domestic production of hydroponic media and for medium development using recycled hydroponic rockwool slabs. Two experiments were conducted to evaluate the growth of plug seedlings of petunia 'Romeo' in various mixtures including particles of used rockwool slabs (rockwool particles) and wood chips. In the first experiment, seedlings were grown in plugs filled with mixtures of steam- sterilized rockwool particles and chestnut wood chips, which had been weathered for six months and screened through either 2.8 mm or 5.6 mm sieve, at the mixing ratio of 100:0, 75:25, 50:50, 25:75, or 0:100 (v/v). In the second experiment, seedlings were grown in plugs filled with twenty different mixtures of steam-sterilized particles of used hydroponic rockwool slabs with 4 mm chestnut or pine wood chips, coir, peatmoss, or perlite. In the first experiment seedling growth was not affected by particle size of chestnut wood chips, was superior in the control (commercial plug medium) and in 100% rockwool particles, but was suppressed as mixing ratio of chestnut wood chips increased. In the second experiment, leaf length, and shoot fresh and dry weights were the greatest in rockwool particles+peatmoss+coir treatment, followed by rockwool particles+peatmoss treatment. Leaf length was suppressed as ratio of wood chips increased, especially of chestnut wood chips. Root development was the greatest in rockwool particles+peatmoss+perlite treatment, followed by the control, and rockwool particles+peatmoss+coir treatment. The growth was suppressed as the mixing ratio of rockwool particles, peatmoss, or coir decreased.

• Fire Science and Engineering
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• v.22 no.3
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• pp.208-215
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• 2008

Existent wood wool cement boards are low-quality cement boards made out of wood chip wastes. Recently, however, they are produced by making wood chips into fibrous forms to have good looks and excellent performances in sound absorption and thermal insulation. Though they have been broadly used in the advanced countries, they were rather expensive products with limited use in Korea having no domestic manufacturers of them. Since 2005, however, it has been possible for the boards to be used in various fields due to their lowered prices and stable supplies by the arrival of domestic manufacturers. For the purpose of encouraging broad use of the boards, this research aims to explore their practical applications by way of assessing the flame retardant and fire resistant performances when they are applied to dry-wall system.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.661-666
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• 2005

The specific objectives of this study were to dry yam chips using microwave vacuum drying, freeze drying and hot air drying, then to coat the dried yam chips with ascorbic acid cocrystallized sucrose, and finally to compare the quality of yam chip snack foods with respect to drying and coating characteristics. The microwave vacuum dried sample showed the highest drying rates and much less surface damage than the hot air dried one did. The shape and color of the microwave vacuum dried/coated sample were allocated between those of the freeze dried/coated sample and the hot air dried/coated sample. The freeze dried/coated sample scored excessively low in organoleptic hardness and chewiness to be suitable as a snack. The hot air dried/coated sample was too deep in color, wrinkled, excessively high in organoleptic hardness and chewiness, and excessively low in mouthfeeling. Therefore, the microwave vacuum dried/coated sample presented the best overall attributes as a snack, with respect to organoleptic characteristics, shape, color, and drying rates.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.4
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• pp.18-27
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• 1998

Biopulping is defined as the treatment of wood chips with lignin-degrading fungi prior to pulping. Fungal pretreatment prior to mechanical pulping reduces electrical energy requirements during refining or increases mill throughput, improves paper strength, reduces the pitch content, and reduces the environmental impact of pulping. Our recent work involved scaling up the biopulping process towards the industrial level, investigating both the engineering and economic feasibility. We envision the process to be done in either a chip-pile or silo-based system for which several factors need to be considered: the degree of decontamination, a hospitable environment for the fungus, and the overall process economics. Currently, treatment of the chips with low-pressure steam is sufficient for decontamination and a simple, forced ventilation system maintains the proper temperature, humidity, and moisture conditions, thus promoting uniform growth of the fungus. The pilot-scale trial resulted in the successful treatment of 4 tons of wood chips (dry weight basis) with results comparable to those on a laboratory. Larger, 40-ton trials were also successful, with energy savings and paper properties comparable with the laboratory scale. The overall economics of the process also look very favorable and can result in significant annual savings to the mill. Although the current research has focused on biopulping for mechanical pulping, it is also beneficial for sulfite chemical pulping and some applications to recycled fiber have been investigated.