Cinnamon leaf oil was obtained by laboratory-scale steam distillation, however, industrial application requires scale-up, since steam flow rate controlled by valve opening influenced characteristics. This study investigates steam valve opening effects on pilot-scale cinnamon leaf oil characteristics. Yield, volatile compound and physicochemical properties were evaluated across ¼, ½, and ¾ valve opening. The results of this study showed a significant difference at 5% significancy level in the specific gravity and refractive index values which the wider valve opening of the steam pipe results in higher specific gravity and refractive index. This was related to the oxygenated compound found in the wider valve opening of the steam pipe. Still, there was no significant difference between the samples in yield, solubility in 70% alcohol, and viscosity. The volatile compounds at the ¼-valve opening of the steam pipe were more diverse compared to the two other samples. The volatile compounds area of this study showed that a wider valve opening in the steam pipe reduces the Area of volatile compounds. Narrower valve openings significantly increase specific gravity and refractive index without affecting yield, alcohol solubility, or viscosity, also produce more diverse volatile compound compositions and higher peak areas.

This study investigated the effects of different alkali types on the physical properties of konjac gel using a rotational rheometer. The aqueous solutions of konjac flour were coagulated using four types of alkali (potassium carbonate, calcium hydroxide, magnesium carbonate, and sodium hydroxide) while standardizing the apparent pH, the amount of hydroxide ions, and the heating time. Amplitude and frequency sweep tests were conducted to evaluate the dynamic viscoelasticity of the formed gels. The results revealed that the type of metal ion significantly affected the physical properties despite the uniform pH conditions. K added gel exhibited a high linear limit but a low flow transition index, indicating a hard but brittle structure with a delicate network. Conversely, Mg added gel showed a low linear limit and a high flow transition index, suggesting a tenacious gel. Ca added gel and Na added gel displayed intermediate characteristics, with Ca added gel showing an uneven network structure. The differences in breakdown behavior were strongly associated with the hydration ability of the metal ions (Mg > Ca > Na > K), rather than the metal valence or minor pH variations. These findings suggest that controlling hydration ability enables the creation of konjac gels with diverse textures.

In the chemical isomerization of common sugars to rare sugars, browning of the reaction mixture due to byproduct formation remains a major challenge. In this study, two aldopentoses, two aldohexoses, and three aldo-disaccharides were utilized as substrates to investigate how the heating rate from room temperature to approximately 115°C at 0.754±0.011 and 0.401±0.007 °C/min (fast vs. slow heating) influences both ketose yield and the degree of browning, the latter of which was evaluated by the change in absorbance at 440 nm (ΔA₄₄₀). For all tested sugars, ΔA₄₄₀ was markedly lower under fast heating than under slow heating conditions during rare sugar production. This trend suggests that the activation energy for isomerization is higher than that for the concurrent browning pathways. Furthermore, the tendency for browning followed the order of pentoses > hexoses > disaccharides. These findings demonstrate that fast heating provides a practical strategy to suppress thermal degradation and browning while maintaining efficient rare sugar production.