Prediksi Kadar Flavonoid, Vitamin C, Dan Brix Pada Ekstrak Kasar Kulit Jeruk Mandarin (Citrus reticulata) Dengan Spektroskopi Visible Near Infrared Tipe Transmitan

Dyan Febri Khoerunisa, Dr. Ir. Rudiati Evi Masithoh, S.T.P., M.Dev.Tech.,IPU., ASEAN Eng., APEC Eng. ; Hanim Zuhrotul Amanah, S.T.P., M.P., Ph.D., IPM

2026 | Skripsi | TEKNIK PERTANIAN

Penelitian ini bertujuan menganalisis karakteristik kimia dan profil spektra ekstrak kasar kulit jeruk mandarin kering (Citrus reticulata) serta mengembangkan model prediksi berbasis Vis-NIR transmitan menggunakan Partial Least Squares Regression (PLSR). Ekstraksi dilakukan menggunakan metode Ultrasound-Assisted Extraction (UAE) dengan variasi waktu dan jenis pelarut. Kadar Total Flavonoid Content (TFC) dan vitamin C diukur menggunakan spektrofotometer UV-Vis, sedangkan nilai Brix diukur menggunakan refraktometer. Hasil pengukuran menunjukkan rata-rata TFC sebesar 61,9 mg QE/L, vitamin C sebesar 218,2 mg/L, dan Brix sebesar 9,8 °Brix. Profil spektra menunjukkan pola yang relatif serupa antarkelompok sampel. Model PLSR terbaik untuk TFC dan vitamin C diperoleh menggunakan Range Normalization, dengan nilai (R²P) masing-masing 0,122 dan 0,316, sedangkan model Brix terbaik menggunakan Standard Normal Variate (SNV), dengan nilai (R²P) sebesar 0,745. Hasil ini menunjukkan bahwa model memiliki kemampuan prediksi lebih baik untuk Brix dibandingkan TFC dan vitamin C, meskipun pengembangan lebih lanjut masih diperlukan untuk meningkatkan kinerja prediksi.

This study aimed to analyze the chemical characteristics and spectral profiles of dried mandarin orange peel (Citrus reticulata) extracts and develop a prediction model based on Vis-NIR transmittance spectra using Partial Least Squares Regression (PLSR). Extraction was performed using the Ultrasound-Assisted Extraction (UAE) method with variations in extraction time and solvent type. Total Flavonoid Content (TFC) and vitamin C contents were measured using a UV-Vis spectrophotometer, while Brix values were measured using a refractometer. The results showed average values of 61.9 mg QE/L for TFC, 218.2 mg/L for vitamin C, and 9.8 °Brix for Brix. The spectral profiles exhibited relatively similar patterns across sample groups. The best PLSR models for TFC and vitamin C were obtained using Range Normalization, with coefficients of determination for prediction (R²P) of 0.122 and 0.316, respectively. Meanwhile, the best model for Brix was obtained using Standard Normal Variate (SNV), with an (R²P) of 0.745. These results indicate that the model performed better in predicting Brix than TFC and vitamin C, although further development is needed to improve predictive performance.

Kata Kunci : kulit jeruk mandarin, UAE, Vis-NIR transmitan, PLSR, TFC, vitamin C, Brix.