Earticle

본 연구는 문헌연구를 바탕으로 하여 전통적인 방법으로 풀을 조제하여 배접하는 경우 첨가제가 풀의 성질 및 접착특성에 미치는 영향을 고찰한 결과이다. 본 연구는 향후 회화문화재의 보존처리용 천연접착제 개발을 위한 기초 자료로 제시하고자 한다. 따라서 본 연구에서는 접착제에 첨가제가 미치는 영향을 검토하기 위하여 임원경제지(林園經濟志), 거가필용사류전집(居家必用事類全集), 다능비사(多能鄙事), 죽여산방잡부(竹嶼山房雜部)에서 공통적으로 사용되고 있는 백반과 황랍을, 장황지(裝潢志)와 제민요술(濟民要術)에서 공통적으로 사용되고 있는 석회를 첨가제로 사용하여 그 특성 즉, 점도, pH, 유연성, 박리강도, 항균성, 방미성, 보존성 등을 측정하여 고찰하였다. 그 결과 첨가제 고유의 특성이 풀의 특성에 큰 영향을 미치는 것을 알 수 있었다. 백반은 유연성을 증가시켰으나, 점도, 접착강도, pH는 감소시켰으며, 황랍은 유연성, 점도, 접착강도, pH를 모두 감소시켰으며, 석회는 유연성, 점도, pH, 접착강도를 모두 증가시키는 경향을 나타내었다.

Traditional paste materials and additives for investigation were selected through careful literature survey. We used the immersed glutinous rice flour, soybean as a traditional paste materials and a yellow wax, alum, and lime as additives. The effect of additives on viscosity, pH, adhesive strength, flexibility, antibacterial activities, mildew resistance, and conservation properties were examined. It was found that there was a relationship between the properties( viscosity, pH, and adhesive strength) and the characteristics of additives. Alum increased flexibilty but decreased viscosity, adhesive strength, and pH. Yellow wax deceased flexibilty, viscosity, adhesive strength, and pH. Lime increased flexibilty, viscosity, adhesive strength, and pH. The conservation properties increased by adding all additive. The present work was therefore carried out with the objective of offering the base datum for keeping traditional papers and textiles using traditional paste.

본 연구는 전통적인 방법으로 배접용 밀가루 수침 풀의 수침기간에 따른 전분의 구조 및 풀의 접착 특성에 미치는 영향을 고찰한 결과이다. 본 연구는 향후 회화문화재의 보존처리용 천연접착제 개발을 위한 기초 자료로 제시하고자 한다. 따라서 본 연구에서는 고급표구(장황)에 사용하는 밀가루 풀의 수침기간이 2년8개월, 4년8개월, 7년인 세 가지 시료를 준비하여 총당함량, 아밀로오스 함량, 결정화도, 입자의 형태 및 크기, 호화특성, 점도, pH, 박리강도 등을 측정하였다. 그 결과 수침기간이 길어질수록 총당함량, 결정화정도, 최고점도, 최저점도, 최종점도, 강하점도, 및 치반점도는 증가하는 경향을 나타내었고 아밀로오스 함량, 호화온도, pH는 감소하는 경향을 나타내었다. 접착강도는 줄어드는 경향이 있었으나 7년 삭힌 시료의 경우 오히려 박리강도가 증가하였다.

This paper reports a study on physical properties of the traditional adhesives for developing natural adhesives. This is to certify that the superiority of tradition through systematic surveys and experiments as well. We used three kinds of starches differing fermentation time(7 years, 4 years 8 months, and 2 years 8 months) which are fermented from wheat flour starches. The amylose contents, total sugar contents, crystallinity, particle size and shape, viscosity, pH, and adhesive strength were examined. The effect of fermentation time on physical properties of fermented wheat flour were studied. It was found that fermentation time effect various physical properties such as total sugar contents, amylose contents, crystallinity, viscosity, and so on.

An advantage to the extrusion of raw potatoes is a reduction in the energy input required to process potato products; however, the effects of extrusion on the properties of raw potato have not been studied. The purposes of this study were to develop a workable extrusion process for raw potato and to study the effects of extrusion conditions on the pasting properties of extruded potato products. The peak viscosity, final viscosity, pasting temperature, water solubility index, and water absorption index of pressed and pressed-dried potato extrudates decreased as die exit temperature increased, whereas they did not change as screw speed increased. The peak viscosity, final viscosity, and water solubility of steam-cooked potato products decreased with extrusion processing; however, they did not change with increasing die exit temperature and screw speed. Potato products with different degrees of depolymerization of extruded potato starch, depending on die exit temperature, were produced from raw potatoes.

This study was conducted to investigate the pasting and sensory properties of different commercial rice cultivars. All samples had adequate moisture content, and Gyeonggi Kosihikari had the lowest protein content (6.75%). Apparent quality of head rice ranged from 85.63 to 98.70% and amylose content was 21.51-26.54%. In a rapid visco analyzer examination, pasting temperature of Gyeonggi Kosihikari was the lowest (84.87). Breakdown of Gangwon Oade (43.64 RVU) was lower that of others, indicating the highest pasting stability. The setback of Jeonam Hitomebore was the lowest (81.56 RVU), suggesting slow deterioration. A texture analysis test showed that Gyeonggi Koshihikari had the lowest hardness and Chungnam Samgwang had the highest adhesiveness. Gyeonggi Koshihikari had the highest sensory scores for appearance, flavor, taste, texture and overall acceptability. These results indicate that Gyeonggi Koshihikari is the most adequate rice product among cultivars.

중국산 일반메밀 1종과 쓴메밀 2종의 껍질과 종피을 제거한 배유의 성분과 호화성질을 비교 분석하였다. 일반메밀은 쓴메밀 보다 상당히 크고 삼각형에 가까우나 쓴메밀-1종은 길쭉한 형태를 취하고 있으며, 쓴메밀-2종은 삼각형에 골이 깊숙이 파져 있는 형태를 보였다. 메밀쌀 가루의 일반성분과 아미노산 함량은 시료간에 차이가 없었고, 루틴 함량은 쓴메밀이 일반메밀보다 22배 이상 많이 함유하고 있었다. 무기질 함량 중 철, 칼슘과 마그네슘함량은 쓴메밀에서 높았고, 아연, 망간과 인 함량은 일반메밀과 쓴메밀 사이에 큰 차이가 없었다. 신속점도계에 의한 호화패턴을 살펴보면 쓴메밀-2종이 최고점도, 최저점도와 breakdown에서 가장 높게 나타났으며, 쓴메밀-1종은 breakdown이 가장 낮은 값을 나타내었다. 쓴메밀의 setback은 일반메밀보다 약 2.2배 컸다. 메밀가루의 색도는 일반메밀과 쓴메밀 사이에 또한 쓴메밀 사이에도 뚜렷한 차이를 보였다.

Composition and pasting properties of endosperms of one common buckwheat (CB) and two tartary buckwheats (TB) grown in China were investigated. No differences were observed in proximate composition and amino acid content between CB and TB. Content of rutin in TB was 22-fold higher than that of CB. Among minerals, iron, calcium, and magnesium contents were higher in TB than CB, whereas zinc, manganese, and phosphorus contents were similar, Pasting properties measured with Rapid visco Analyzer revealed TB-2 cultivar had highest peak viscosity, trough, and breakdown, followed by TB-1 and CB. Setback of TB was about 2.2-fold greater than that of CB. Significant differences in color were observed between CB and TB, and among TB cultivars.

Physicochemical properties of starches isolated from 3 new potato cultivars developed by Potato Valley Ltd. wereinvestigated and compared to those of starch isolated from ‘Superior’ being distributed prominently in Korea. Significantdifferences were observed in physicochemical properties such as granule size, amylose content, phosphorus content, waterbinding capacity, swelling power, solubility, and in vitro digestibility of starches from different potato cultivars. Thermalproperties were evaluated using differential scanning calorimetry (DSC), and onset gelatinization temperatire (To), peaktemperature (Tp), and enthalpies of gelatinization (∆H) of different potato cultivars ranged as 58.0±0.3-61.7±0.4oC, 63.7±0.2-66.5±0.0oC, and 15.6±0.5-17.0±0.3 J/g, respectively. Pasting properties were evaluated using a rapid visco analyzer (RVA),and pasting temperature, peak viscosity, and final viscosity of different potato cultivars ranged as 65.0±0.1-68.9±0.1oC,8,163.7±196.3-9,035.7±6.4 cp, and 4,397.7±166.7-7,025.0±271.3 cp, respectively. Especially, ‘Gogu valley’ starch showedthe highest values in the amylose and phosphorus content among tested potato cultivars and higher water binding capacity,swelling power, and solubility than those of other tested starches. And it also showed high pasting temperature, peak viscosity,trough viscosity, and final viscosity as compared to other tested starches.

Plentiful amount of spent yeast has been produced as a by-product from breweries. B-Glucan was prepared from the spent brewer's yeast in a crude form with hot water extraction and subsequent enzymatic treatment. The crude B-Glucan preparation consisted of mainly glucan (53% of total wt), containing approximately 35% B-Glucan content of total weight. The effects of crude B-Glucan substitution (1-9%) on pasting properties of wheat flour and starch were determined using a Rapid Visco-Analyzer (RVA). Incorporation of yeast B-Glucan into wheat flour and starch significantly decreased peak and [mal viscosities, but slightly increased setback viscosity. The setback viscosity was considerably higher in starch/B-Glucan suspension than in flour/B-Glucan suspension. It was suggested that preparation of yeast B-Glucan into aqueous dispersion might affect pasting behaviors of wheat flour and starch.

Com and rice starches were physically modified by planetary mill. While native starches showed high peak viscosities (1,001 and 563 cp), it decreased largely (42 and 20 cp for rice and com starch, respectively) after 2 hr of physical modification. When two starches were co-ground, peak viscosities decreased more largely than single ground one only in 30 min, indicating the pasting properties could be easily changed by co-grinding. Especially, the higher the amount of com starch, the viscosity decreased more largely, which means that paste stability could be controlled also by changing the ratio of com and rice starch. Mean particle size increased with physical modification time since particles became spread because of shear force. There were also changes in surface morphology after physical modification. Fluid property, such as mean time to avalanche (MTA), was improved (from 6.16±0.47 and 8.37±1.23 sec to 5.47±0.78 and 5.26±1.37 sec for rice and com starch, respectively) by physical modification. Pasting property, such as swelling power, was also improved by physical modification. These mean that native starches can be applied to both conventional powder and new paste-food industry more efficiently by physical modification.

The effects of gellan gum (from S. paucimobilis), EPS-CB (exopolysaccharide from S. chungbukensis), and a series of commercial gums (arabic gum, xanthan gum, guar gum, deacyl gellan gum), on the swelling, rheological, and pasting properties of non-waxy rice flour dispersions were investigated. The swelling properties of rice flours in gellan or guar gum dispersion after heating were found to have increased with increasing gum concentrations, but the swelling properties of rice flour/other gum systems decreased with increasing concentrations. The rice flour/gum mixtures showed high shear-thinning flow behavior (n=0.14-0.32), and consistency index (K) was higher in guar gum than other gum dispersions. The initial pasting temperatures and peak times increased along with increasing gum concentration. The peak viscosity of rice flour increased in guar gum and deacyl gellan dispersions, and the breakdown and setback viscosity of the rice flour paste was lowest in the xanthan gum system, but remained higher than those of the control. The apparent viscosities of the rice flour/gellan gum mixture pastes were the highest among the tested combinations.

The aim of this study was to produce resistant starch preparations from acid-modified com starches prepared at various hydrolysis levels (0.5-4.0 hr). Effect of autoclaving cycles on resistant starch (RS) formation was investigated. Molecular weight distribution, pasting and functional properties of acid-modified com starches were determined. For RS formation native and acid-modified starch samples were gelatinized and autoclaved (1 or 2 cycles). While native and acid-modified starches did not contain any RS, the levels increased to 9.0-13.5% as a result of storage at 95℃ after first autoclaving cycle. Second autoclaving cycle together with storage at 95℃ brought final RS contents of the samples incubated at 4 and 95℃ after the first cycle to comparable level. As acid modification level increased, the amount of high molecular weight fractions decreased, resulting in significant decreases in viscosities (p<0.05). The samples produced in this study had low emulsion stability and capacity values.

Moisture content of normal, waxy, and high amylose com starches was adjusted to 10-35%, and irradiated in a microwave oven. The effect of microwave irradiation on the crystalline structure of starch was measured by using a differential scanning calorimetry (DSC), and X-ray diffractometry. Pasting viscosity profile was also determined by using a rapid viscoanalyzer (RVA). For all the 3 types of starches tested, the rate of temperature increase by the microwave irradiation was faster and more rapidly reached the maximum temperature of the pressure bomb (120℃) when the moisture content was higher. X-ray diffraction and DSC data revealed that the microwave irradiated starch underwent partial disruption of crystalline structure. RVA studies showed that the irradiation caused significant reductions in maximal viscosity and breakdown, whereas pasting temperature was increased. Overall trends revealed that the microwave irradiation on the starch containing limited moisture content (less than 35%) provided the effects similar to the heat moisture treatment. These effects became more significant when the moisture content was higher. Compared to waxy com starch, normal, and high amylose com starches appeared to be more susceptible to the microwave irradiation.

도복 현미와 백미 곡립의 경도는 도복 시간에 따라 감소하였고, 무도복 현미와 백미의 경도는 오히려 증가하였다. 도복 현미와 백미의 DSC 열적 성질(To, Tp, Tc, ΔH)은 도복 시간에 따라 감소하였고, 무도복 현미와 백미의 경우는 증가하였다. 현미 백미 곡립의 경도와 DSC 열적 성질, 특히 ΔH와 Tp는 밀접한 상관관계를 보였다. 도복 현미와 백미의 RVA 호화 특성(최대점도, 최저점도, 최종점도, breakdown, consistency)은 도복 시간에 따라 감소하였고, 무도복 현미와 백미의 경도는 오히려 증가하였다. 다 만 setback의 경우는 일정한 경향을 보이지 않았다. 도복 현미밥과 백미밥의 경도, 응집성, 검성, 씹음성, 부착성, 탄성은 도복 시간에 따라 감소하였고, 무도복 현미밥과 백미밥의 경우는 증가하였다. 다만 응집성과 부착성은 백미가 현미보다 높았다.

This study was conducted to determine and compare hardness, thermal properties (by DSC), pasting properties (by RVA) and texture of brown rice and white rice, either lodged or non-lodged, with respect to lodging time. The hardness and the thermal properties of lodged brown rice and white rice decreased with lodging time, while those of nonlodged brown and white rice increased. In addition, the rice kernel hardness and the thermal properties had high correlation coefficients. The pasting properties, with the exception of setback, and the textural properties of lodged brown and white rice decreased with lodging time, while those of non-lodged brown and white rice increased.

3%의 콩단백질을 첨가한 옥수수전분 용액을 건조가열 시켜 만든 시료의 호화특성, 겔의 조직감 및 노화특성에 대해 연구하였다. 건조가열로 만들어진 시료의 경우, 단순 혼합 시료보다 낮은 pasting 온도와 높은 RVA 점도들을 보였으며 유의적으로 낮은 호화엔탈피를 보였다. 높은 온도에서 건조가열한 시료(heated sample)의 경우, 낮은 온도에서 건조가열한 시료(unheated sample)보다 pasting 온도가 낮았으며 peak viscosity, breakdown viscosity가 유의적으로 높았다. 또한 pH가 증가할수록 보다 높은 점도 profile을 보였다. 가열 건조한 시료는 낮은 파괴강도 및 파괴 strain을 보였으며 pH가 높을수록 elastic modulus와 파괴강도는 감소하고 파괴 strain은 증가하였다. 콩단백질의 첨가와 더불어 건조가열은 전분의 노화방지에 도움을 주며 겔의 미세구조를 변화시켜 겔의 조직감을 변화시켰다. 전분의 호화 및 노화특성과 겔의 조직감을 콩단백질의 첨가와 더불어 건조가열과 pH 조절을 이용하여 변화시킬 수 있었으며, 이는 전분의 호화온도와 단백질의 변성온도 이하의 온도에서 건조 후 고온 건조가열을 통해 전분-단백질의 구조적 변성과 결합을 유도하여 새로운 기능성 전분을 만들 수 있는 가능성을 보여준다.

Effects of dry heating and pH on pasting, thermal, and textural properties of corn starch containing soy protein isolate (SPI) were investigated. Samples were prepared by drying corn starch dispersions containing 3% SPI at 40℃ (unheated sample) or additionally heating dried mixtures at 130℃ (heated sample). Pasting properties of starch samples and textural properties of starch gels were measured using Rapid Visco-Analyzer (RVA) and Texture Analyzer (TA), respectively. Effects of SPI addition and dry heating on retrogradation and microstructure of gel samples were investigated using DSC and SEM, respectively. Pasting viscosity of dry-heated samples was significantly higher than that of unheated samples, and at pH 8 compared to pH 6. Dry-heat treatment decreased fracture stress and strain of starch gels containing SPI. No significant effects of dry-heat treatment and pH were observed on retrogradation of starch gels. Addition of SPI retarded starch retrogradation and modified starch gel properties with increased nutritional value. Dry-heat treatment with SPI could be possible method for starch modification.

Ohmic heating is an internal heating method based on the principle that when an electrical current passes through food, electric resistance heat is uniformly generated internally by food resistance. Previous studies indicate that the thermal properties, external structure, internal structure, and swelling power of ohmic heat treated starch of various starches, such as potato, wheat, corn, and sweet potato, differed from those of conventional heating at the same temperature. In this study, the pasting property of starch, treated with ohmic and conventional heating, were measured by RVA (Rapid Visco-Analyzer). Our results show that as the ohmic heating temperature increased, the PV (Paste Viscosity) of the starch decreased significantly, and the PT (Pasting Temperature) increased. Changes in PV and PT indicate that the swelling of starch remains unchanged by ohm heating. The HPV (Hot Paste Viscosity), CPV (Cold Paste Viscosity) and SV (Setback Viscosity) of ohmic heated starch also differed from the conventional heated starch. The pasting property is similar to the viscosity curve of common cross-linked modified starch. In this experiment, we further confirm the similarity with modified starch and its usability.

Seven rice cultivars with different eating qualities, especially pasting and physicochemical characteristics of the carbohydrates components in rice endosperm, were analyzed for their correlation with the palatability score (Toyo value). The Toyo values showed significant differences among the seven cultivars: Samgwangbyeo>Gopumbyeo>Chuchungbyeo>Ilpumbyeo>Palgongbyeo> Samnambyeo>Dobongbyeo. Examination by a rapid visco analyzer showed the temperature of pasting was the lowest in Ilpumbyeo and the highest in Dobongbyeo. Rice cultivar having high enthalphy for gelatinization by differential scanning calorimeter and low palatability score showed high-crystalline starches. No significant differences were observed among cultivars in amylose contents of rice starches except Dobongbyeo and Chuchungbyeo. The abundant fatty acids of rice starch lipids were palmitic, linoleic and oleic acids, and rice cultivars with high eating quality had high contents of linoleic and linolenic acids.