OPTIMASI DAN EVALUASI LILIN AROMATERAPI KOMBINASI MINYAK ATSIRI KULIT LEMON (Citrus limon) DAN MINYAK ATSIRI BUNGA KAMBOJA (Plumeria rubra) DENGAN VARIASI ASAM STEARAT DAN PARAFIN MENGGUNAKAN METODE SLD

Abstrak
Latar Belakang: Lilin aromaterapi merupakan salah satu sediaan nonfarmakologi yang banyak digunakan untuk memberikan efek relaksasi melalui pelepasan aroma minyak atsiri. Karakteristik fisik lilin aromaterapi sangat dipengaruhi oleh komposisi bahan basis, khususnya perbandingan asam stearat dan paraffin wax. Penelitian ini bertujuan untuk memperoleh formula optimum lilin aromaterapi kombinasi minyak atsiri kulit lemon (Citrus limon) dan minyak atsiri bunga kamboja (Plumeria rubra) menggunakan metode Simplex Lattice Design (SLD) pada aplikasi Design Expert 13.

Metode: Penelitian ini merupakan penelitian eksperimental dengan lima variasi formula berdasarkan proporsi asam stearat dan paraffin wax. Evaluasi meliputi uji organoleptis, homogenitas, titik leleh, waktu bakar, serta uji kesukaan terhadap aroma dan warna selama penyimpanan 28 hari pada suhu ruang dan cycling test. Data titik leleh dan waktu bakar dianalisis menggunakan metode Simplex Lattice Design, kemudian formula optimum diverifikasi menggunakan uji paired sample t-test

Hasil: Seluruh formula memenuhi persyaratan mutu fisik dan tetap stabil selama penyimpanan. Peningkatan konsentrasi asam stearat meningkatkan titik leleh serta memperpanjang waktu bakar lilin. Formula optimum diperoleh pada komposisi 10% asam stearat dan 90% paraffin wax dengan nilai desirability mendekati 1. Hasil verifikasi menunjukkan nilai prediksi titik leleh sebesar 53,39°C dan hasil evaluasi sebesar 53,33°C, sedangkan prediksi waktu bakar sebesar 3,29 jam dan hasil evaluasi sebesar 3,08 jam. Analisis paired sample t-test menunjukkan tidak terdapat perbedaan yang signifikan antara nilai prediksi dan hasil aktual (p>0,05), sehingga model optimasi dinyatakan valid.

Kesimpulan: metode Simplex Lattice Design mampu memprediksi formula optimum secara valid serta menghasilkan lilin aromaterapi yang memenuhi persyaratan mutu fisik dan memiliki kestabilan yang baik selama penyimpanan.

Abstract
Background: Aromatherapy candles are widely used as a non-pharmacological therapy to promote relaxation through the release of essential oil vapors. The physical characteristics of aromatherapy candles are greatly influenced by the composition of the base materials, particularly the ratio of stearic acid to paraffin wax. This study aimed to determine the optimum formulation of an aromatherapy candle containing a combination of lemon peel essential oil (Citrus limon) and frangipani flower essential oil (Plumeria rubra) using the Simplex Lattice Design (SLD) method with Design Expert 13 software.

Method: This study employed an experimental design involving five formulations with varying proportions of stearic acid and paraffin wax. The evaluations included organoleptic, homogeneity, melting point, burning time, and hedonic tests on aroma and color during 28 days of storage at room temperature and under cycling test conditions. The melting point and burning time data were analyzed using the Simplex Lattice Design method, and the optimum formulation was subsequently verified using a paired sample t-test.

Results: throughout the storage period. An increase in stearic acid concentration increased the melting point and prolonged the burning time of the candles. The optimum formulation consisted of 10% stearic acid and 90% paraffin wax, with a desirability value close to 1. The verification results showed that the predicted melting point was 53.39°C, while the experimental value was 53.33°C. Likewise, the predicted burning time was 3.29 hours, whereas the observed value was 3.08 hours. The paired sample t-test analysis indicated no significant difference between the predicted and actual values (p > 0.05), confirming the validity of the optimization model.

Conclusion: The Simplex Lattice Design method was able to validly predict the optimum formulation and produce aromatherapy candles that met the required physical quality standards and exhibited good stability during storage.