This study investigated the physicochemical properties and acceptability of yellow layer cake prepared using various levels of wet-milled rice flour (RF). RF was used to substitute 0% (control group), 15% (RF-15 group), 30% (RF-30 group) and 45% (RF-45 group) of wheat flour (WF) to manufacture yellow layer cakes. The substitution of WF with RF showed no significant effect on the pH but decreased the specific gravity and viscosity of the batter. Baking loss rates ranged from 4.65% to 5.03%, showing no significant difference among samples. In the color measurement, the experimental groups showed higher redness (a) and yellowness (b) than the control group (p<0.05). The experimental groups showed lower gumminess and chewiness than the control group. According to the results of intensity measurement of sensory properties, the RF-30 and RF-45 groups showed stronger intensities for darkness, sweetness, moistness and softness than the control group. The acceptance test found that the RF-45 group had significantly higher or similar results for all acceptance attributes than the control group. These results indicate that RF addition as a replacement of WF at a ratio of 45% is optimal for producing yellow layer cakes.

흑마늘을 새로운 기능성 식품의 재료로 사용하기 위하 여 흑마늘 분말을 첨가한 옐로우 레이어 케이크를 제조 하여 비중, 점도, 색도, 텍스처 및 관능검사와 같은 품질 특성을 조사하였다. 반죽의 비중은 흑마늘의 첨가량에 상관없이 모든 실험구에서 유의적인 차이를 보이지 않았 으며, 반죽의 점도는 31,315~41,048 cP로 흑마늘 분말 첨가량이 증가할수록 증가하였다. 케이크의 pH는 7.54~ 6.18로 흑마늘 분말 첨가량이 증가함에 따라 유의적으로 감소하는 경향을 보였으며, 케이크의 높이 또한 6.14~ 5.62 cm로 흑마늘 분말 첨가량이 증가 할수록 유의적으 로 감소하는 경향을 보였다. 케이크의 비용적은 5%, 10% 첨가구에서는 대조구와 차이를 보이지 않았으나 15% 첨가구에서는 감소하는 것으로 나타났다. 케이크 색도를 측정한 결과 L값은 흑마늘 분말의 첨가량이 증가 함에 따라 대조구에 비하여 감소하는 경향을 나타내었으 며, a값은 흑마늘 분말 첨가량이 많을수록 증가하는 경 향을 보였다. b값의 경우 crust에서는 흑마늘 분말의 첨 가량이 증가할수록 감소하는 경향을 보였으나 crumb과 batter에서는 증가하다가 감소하는 경향을 나타내었다. 조직감을 측정한 결과 견고성, 부착성 및 응집성은 흑마 늘 분말의 첨가 비율이 증가할수록 점차적으로 증가하였 다. 관능검사 결과 전체적인 기호도는 5% 첨가구에서 가 장 높은 것으로 나타났다.

In the making of yellow layer cake, shortening was replaced with olive oil at levels of 25, 50, 75, and 100%. The hunter values of L and b showed that the crumb colors of the cakes with 50 and 75% olive oil were significantly different from that of the control. Both 50 and 75% olive cakes showed a higher specific gravity of batters, and lower specific volume of cakes, than the control. Cakes with 50 and 75% olive oil were less hard than the control during 3 days’ storage at 22oC. Sensory evaluation showed that their characteristics - cell uniformity, crumb color, taste, softness, and moistness - were not influenced by the replacement of shortening with olive oil. And same as above for overall acceptance.

Physicochemical qualities and consumer acceptability of chocolate layer cake were studied with varied levels of rosemary powder at 0, 0.2, 0.4 and 0.6%. The ash content of the cake increased from 2.30 to 3.10%, as the amount of rosemary powder increased from 0 to 0.6%, and the carbohydrate content of the cake decreased as the addition of rosemary powder increased. There were no significant differences in moisture contents and pH values among the samples and the pH values of all samples were within the typical pH range of 7.5-8.0 for chocolate， layer cakes. Water loss from the control cake was greater than that from the cakes with rosemary powder supporting the suggestion that the addition of rosemary powder to the chocolate layer cake could increase moisture retention of the cake. Consumer acceptability of all the samples showed higher prefierences of more than 7 points. Rosemary aroma, mint flavor and after taste were highly positively corrεlated with the fat content. Fat and ash content of the cake, which tended to increase in proportion to the rosemary powder content， were negatively correlated with acceptance of herb flavor, sweet taste, moistness， softness and intensity of softness but positivεly correlated with intensity of herb flavor. With the results above, trials on chocolate layer cake using rosemary powder were successfully performed within the ranges tested.

Fat and sugar reduced yellow layer cake system was developed with varied replacement level of 30%, 60%, and 90% for AD(amylodextrin) and 10%, 30%, and 50% for PD(polydextrose). Physicochemical and sensory characteristics were investigated and optimum replacement level was also decided using response surface methodology. Sample groups of PD10AD30 had significantly the lowest specific gravity and viscosity, indicating the stable batter system with high air incorporation. Sample groups with PD10AD90 showed the highest volume index and were not significantly different from those of the PD10AD30. Sensory results indicated that PD30AD30 were significantly the most springy and moist, and the least hard of all sample groups. Sample groups with PD10AD90 had the least adhesiveness value. To establish the optimum substitution level using RSM, the restriction level was set up as moistness over five point, hardness under five points, and adhesiveness under four points. The optimum substitution level was 20% for PD and 88% for AD.

The resistance in series model has been frequently used for determination of various filtration resistance to correctly understand the membrane fouling behaviour in MBR (membrane bio-reactor) for wastewater treatment. The cake layer resistance (Rc) which is commonly determined by calculation of flux dataset that are obtained empirically before and after removing the cake layer on membrane surface. However, the calculated Rc values are very dependent on the cleaning methods adapted for removal of cake layer. This study investigated how the various cleaning options affect Rc. Seven different cleaning methods were employed: i) ultrasonication (100 W, 10 min), ii) ultrasonication (200 W, 60 min), iii) ultrasonication (400 W, 120 min), iv) water rinsing in a shaker (100 rpm, 10 min), v) water rinsing in a shaker (300 rpm, 60 min), vi) water rinsing, vii) sponge scrubbing. For the hydrophilic PES membrane, the cake layer removal efficiencies ranged from 64% to 10%, indicating that the removal of cake layer was highly dependent on the cleaning options. For the hydrophobic PVDF membrane, the cake layer removal efficiencies ranged from 79% to 97%. Consequently, a standardized method for cake layer removal to determine cake resistance (Rc) is needed for correct interpretation of the fouling phenomena.

보리순 분말이 yellow layer cake의 품질 특성에 미치는 영향을 조사하기 위하여 보리순 분말을 밀가루의 0, 2, 4, 6, 및 8%의 수준으로 대체하여 첨가하였다. 보리순 분말을 함유한 반죽의 점성은 대조구보다 증가하였으며 반죽의 비중은 낮게 나타났다. 케이크의 비체적은 시료간에 차이가 없는 것으로 나타났다. Volume index는 대조구가 가장 낮게 나타났으며 symmetry index와 uniformity index는 차이가 없