The organoleptic test was conducted through direct observation by three panelists using their five senses to evaluate the syrup preparation, including its color, aroma, taste and appearance. A good syrup should have a distinctive taste, aroma and color that reflect the characteristics of the extract used (Fickri, 2018).

The clarity test was carried out to ensure that the preparation is free from impurities or foreign particles. The test was conducted in three replications by pouring the syrup into a beaker glass and observing it visually by placing the glass against a white background and illuminating it with light (Nuzzaibah & Ermawati, 2023).

The homogeneity test was conducted to ensure that the syrup preparation is evenly mixed. The test was performed in three replications by pouring the syrup into a 50 mL volumetric flask and observing it visually under lighting. A good syrup should be homogenous, with no clumps or sediment, stable and not cloudy (Hidayati et al., 2020).

The pH test was conducted to measure the acidity level of the syrup using a pH meter and to ensure that the resulting syrup preparation is safe for consumption. A good syrup should have a pH value between 4 and 7. The test was performed in thre replications (Kemenkes, 2020).

The specific gravity test was conducted to ensure that the specific gravity of the produced syrup meets the established standard specifications. A good syrup should have a specific gravity value of > 1.2 g/mL. The test was performed in three replications by weighing an empty pycnometer, a pycnometer filled with distilled water and a pycnometer filled with syrup, then calculating the result using a formula (Fitriana et al., 2022).

The displaced volume test was conducted to ensure that the syrup volume is accurate and meets the required specifications. The test was performed in three replications by pouring the syrup from the bottle into a measuring cylinder and observing the volume obtained (Nuzzaibah & Ermawati, 2023).

The pouring time test was conducted to determine how easily the syrup preparation can be poured. The test was performed in three replications by pouring 50 mL of syrup into a beaker glass at a 45^o angle and observing the duration required for the syrup to completely flow out of the bottle (Hidayati et al., 2023).

The viscosity test was conducted to measure the thickness of the syrup preparation, which represents the fluid’s resistance to flow. The test was carried out using a Brookfield viscometry by immersing spindle no. 3 into a beaker containing 250 mL of syrup solution and starting the instrument at a speed of 50 rpm, then observing the reading on the viscometer monitor (Heramuda & Wuryandari, 2019). The test was performed in three replications. A good syrup should have a viscosity value ranging from 27 to 396 cPs (Kemenkes, 1995).

The results of the organoleptic tests carried out on the four formulations with direct observation from the three panelists are shown in the table below. From the table above, it can be seen that Formulas 1 has a different color and aroma from the other formulas. The pink color obtained comes from the addition of essence without the addition of extract, so the resulting aroma is also predominantly the aroma of the essence. Meanwhile, Formulas 2, Formulas 3, and Formulas 4 produce a reddish-brown color that is increasingly concentrated with an increasingly sharp aroma of extract as the amount of extract added to the syrup preparation increases.

The results of the clarity tests carried out on the four formulations with direct observation from the three panelists are shown in the table below. The table above show that all formulas have a clear physical appearance, with no foreign particles observed floating in the middle of the syrup preparation. These results indicate that the syrup formulation process was carried out properly, with no foreign particles present that could affect the quality of the preparation. Clarity is one of the key aspects used to assess quality of a syrup preparation, as it can influence both physical stability and consumer acceptance. If the syrup is muddy or contains foreign particles, it will potentially reduce consumer confidence in the quality and safety of the product.

The results of the homogeinity tests the four formulations are shown in the table below. The table above shows that all formulas exhibit a homogeneous physical appearance, as no sediment was observed at the bottom of the syrup. These results are consistent with the findings of (Sari & Pujiastuti, 2024), which state that all components of a syrup must be evenly mixed without any sediment or separated particles. Uniform mixing indicates that the sungkai leaf extract has good solubility in the solvent used, namely distilled water (aquadest). Homogeneity is one of the key indications in assessing physical stability. Physically unstable syrup many undergo changes in homogeneity, such as sedimentation at the bottom (Yati et al., 2018). External factors such as exposure to light, air or temperature or internal factors such as incompatibility between components, can cause this separations (Fitriana et al., 2022)

The results of the pH tests conducted the four formulations are shown in the table below. The pH test results of sungkai leaf extract conducted by (Sekardjati et al., 2023) showed a pH value of 5.25. The pH test results of the four sungkai leaf extract syrup formulas fall within the acceptable pH range for syrups, which is 4-7. As shown in Table 6, an increase in pH value was observed in Formula 2 and Formula 3, which occurred in line with the increasing amount of sungkai leaf extract added to the syrup. This finding align with research by (Nuzzaibah & Ermawati, 2023). The decrease in pH in Formula 4 occurred due to oxidation of compounds in the preparation, which can change its structure and reduce the effectiveness of the syrup. The pH value of sungkai leaves obtained is categorized as a weak acid, so the most significant factor that can influence changes in the pH of the syrup preparation is differences in acid concentration or the occurrence of an oxidation process. In this study, pH changes can occur due to the oxidation process in the materials used. Propylene glycol can oxidize if exposed to oxygen or when the material is left open and not covered with aluminum foil. Oxidized propylene glycol can reduce the final pH value of the preparation.

Based on the results of statistical analysis using the Kruskal-Wallis test, it showed a significant difference in data distribution between formulas, indicated by a p-value of 0.029 (<0.05). The difference in data distribution was caused by variations in formulation composition and processing conditions. Therefore, the addition of extracts can affect the pH value of the resulting syrup.

The results of specific gravity test conducted the four formulations are shown in below. The specific gravity test results for all formulas were within the acceptable range for syrup, which is > 1.2 g/mL (Kemenkes, 2020). As shown in Table 7, a decrease in specific gravity values was observed in Formulas 2 and Formulas 3, which was caused by an increased amount of extract in the syrup preparation.

This is in line with the findings of (Sari & Pujiastuti, 2024), which stated that lower specific gravity values are associated with higher concentrations of active ingredients. The increase in specific gravity in Formulas 4 was influenced by external factors such as temperature and the viscosity of the preparation. At higher temperatures, compounds tend to evaporate, making the preparation more concentrated and thus affecting the specific gravity of the resulting syrup (Sari & Pujiastuti, 2024). Additional ingredients that can evaporate when mixed with the hot sucrose solution, such as propylene glycol, which can interfere with the solubility of methylparaben, resulting in inconsistent physical evaluation results from each iteration. Based on statistical analysis using the Kruskal-Wallis test, the significance value obtained was p = 0.183 > 0.05, indicating that the addition of extract does not have a significant effect on the specific gravity of the syrup.

The results of delivered volume test conducted on the four formulations are shown in below. The results of the delivered volume test, as shown in Table 8, indicate that all four syrup formulations have a final volume 100 mL. This demonstrates that the calculation process, formulation and filling into bottles were carried out consistently, reflecting the product’s compliance with the expected quality standards. According to the Pharmacopoeia ed 6^th, the transferred volume is considered acceptable if the average volume of each tested sample falls within the range of 95-100%. Accurate volume is very important as it directly relates to the dosage and effectiveness of the syrup.

The results of pouring time test conducted the four formulations are shown in below. The pouring time test conducted on the four formulas produced varying durations. As shown in Table 9. There was an increase in Formula 2, followed by a decrease in Formula 3 and then an increase again in Formula 4. This result differs from the outcomes of the specific gravity and viscosity test. The increase in pouring time is in line with the study by (Hidayati et al., 2020), which stated that pouring time tends to increase with the addition of extract in syrup preparations. Variations in pouring time values may be influenced by external factors such as temperature, pouring angle and the speed at which the syrup is poured from the bottle. Based on statistical analysis using the One-Way ANOVA test, the significance value obtained was p= 0.800 > 0.05, indicating that the addition of extract does not have a significant effect on the pouring time value.

The results of viscosity test conducted on the four formulations are shown in below. The viscosity test results for the four formulas fall within the acceptable viscosity range of 27-396 cPs (Kemenkes, 1995). As shown in Table 10, a decrease in viscosity was observed in Formulas 2 and 3, which was caused by the increased amount of sungkai leaf extract in the syrup preparation.

This finding aligns with the study by (Murrukmihadi et al., 2019), which stated that the higher the concentration of extract added, the lower the resulting viscosity. The increase in viscosity observed in Formula 4 is influenced by external factors such as temperature. The higher the temperature of the preparations, the more evaporation occurs among the compounds within, resulting in a thicker syrup (Sari & Pujiastuti, 2024). This can be influenced by the temperature of the sucrose solution when preparing the syrup, when the hot sucrose solution is directly mixed with additional ingredients such as citric acid, it can affect the resulting viscosity value. Based on statistical analysis using the Kruskal-Wallis test, a significant difference was found between formulas with a p-value of 0.017 < 0.05, indicating that the addition of extract has a significant effect on the viscosity (thickness) of the resulting syrup.