Prediksi Umur Simpan Teh Hitam Berdasarkan Pendekatan Kadar Air Kritis: Studi Kasus pada PT Pagilaran

Syeni Novitasari, Prof. Dr. Ir. Supriyadi, M.Sc.; Taufan Alam, S.P., M.Sc.

2025 | Skripsi | TEKNOLOGI PANGAN & HASIL PERTANIAN

Teh hitam merupakan produk yang higroskopis dan rentan mengalami kemunduran mutu akibat kenaikan kadar air. Penelitian ini bertujuan untuk memprediksi umur simpan teh hitam produksi PT Pagilaran berdasarkan pendekatan kadar air kritis menggunakan model isoterm sorpsi lembab (ISL). Sampel yang diuji meliputi lima grade teh hitam (BOP, BOPF, PF II, F II, dan D III) dengan dua jenis kemasan berbeda yaitu paper sack dan karung plastik woven polypropylene (PP) berlapis inner polyethylene (PE). Kurva ISL diperoleh melalui metode gravimetri pada lima titik RH (11–97%) menggunakan larutan garam jenuh LiCl, MgCl?, Mg(NO?)?, NaCl, dan K?SO?. Data kadar air kesetimbangan (Me) diplot ke tujuh model persamaan matematis (BET, GAB, Henderson, Halsey, Chen-Clayton, Caurie, dan Oswin) dan divalidasi menggunakan nilai Mean Relative Determination (MRD).

Hasil menunjukkan bahwa semua sampel menunjukkan pola ISL tipe II (sigmoid), dengan model GAB sebagai model yang paling sesuai. Kadar air lapis tunggal (Mo) ditentukan dari parameter GAB, sedangkan kadar air kritis ditetapkan pada nilai Aw ? 0,6 berdasarkan titik kenaikan tajam pada kurva GAB. Laju transmisi uap air (WVTR) dan permeabilitas kemasan dihitung menggunakan metode ASTM E-96. Estimasi umur simpan paling lama adalah grade BOP yang dikemas dengan paper sack, sedangkan umur simpan paling singkat adalah grade Fanning yang dikemas dengan karung plastik woven PP yang dilapisi inner PE.

Black tea is a hygroscopic product that is susceptible to quality deterioration due to an increase in moisture content. This study aims to predict the shelf life of black tea produced by PT Pagilaran based on the critical moisture content approach using the moisture sorption isotherm model. Samples tested included five grades of black tea (BOP, BOPF, PF II, F II, and D III) with two different types of packaging: paper sack and woven polypropylene (PP) plastic sack lined with polyethylene (PE) inner. ISL curves were obtained through the gravimetric method at five RH points (11-97%) using saturated salt solutions of LiCl, MgCl?, Mg(NO?)?, NaCl, and K?SO?. Equilibrium moisture content (Me) data were plotted onto seven mathematical equation models (BET, GAB, Henderson, Halsey, Chen-Clayton, Caurie, and Oswin) and validated using Mean Relative Determination (MRD) values.

Results showed that all samples exhibited ISL type II (sigmoid) patterns, with the GAB model being the best fit. The single-layer moisture content (Mo) was determined from the GAB parameters, while the critical moisture content was fixed at Aw ? 0.6 based on the sharp rise point on the GAB curve. Water vapor transmission rate (WVTR) and package permeability were calculated using the ASTM E-96 method. The longest estimated shelf life was BOP grade packed with paper sacks, while the shortest shelf life was Fanning grade packed with PP woven plastic sacks lined with PE inner.

Kata Kunci : teh hitam, isoterm sorpsi lembab, WVTR, umur simpan