Pendugaan Umur Simpan Lemon (Citrus limon) dengan Pendekatan Multivariate Accelerated Shelf Life Testing (MASLT)

Abstract

Umur simpan suatu produk dipengaruhi oleh beberapa parameter mutu secara simultan. Pendugaan umur simpan dengan pendekatan Multivariate Accelerated Shelf Life Testing (MASLT) diharapkan mampu menduga umur simpan dengan lebih tepat. Penelitian ini bertujuan (1) mengkaji pengaruh suhu terhadap mutu buah lemon, (2) mengkaji umur simpan buah lemon dengan pendekatan Multivariate Accelerated Shelf Life Testing (MASLT), (3) menduga umur simpan buah lemon pada berbagai suhu penyimpanan. Buah lemon diperoleh dari petani di Lembang, Kab. Bandung Barat berukuran 132.7 g dipanen pada umur 1 tahun setelah pembungaan. Sebanyak 21 buah lemon dicuci dan disimpan pada suhu 25, 35, dan 45 ℃. Perubahan mutu lemon diamati setiap 1 hari selama 7 hari meliputi total padatan terlarut, kadar air, kekerasan, susut bobot, dan warna lemon. Pengamatan pada suhu 45 ℃ dihentikan ketika sampel mendapatkan skor hedonik kurang dari 2.5. Principal Component Analysis (PCA) digunakan untuk mereduksi banyak parameter mutu lemon yang diamati. Hasil penelitian menunjukkan sebanyak 91.29% varian dari seluruh data pengamatan dapat dijelaskan oleh principal component pertama (PC1). Kinetika multivariat perubahan parameter mutu mengikuti reaksi orde nol. Plot ln km terhadap 1/T menunjukkan nilai energi aktivasi multivariat (Ea) sebesar 62.99 kJ/mol dengan faktor pra-eksponensial (k0) sebesar 3.87 × 1010 skor PC1/hari. Faktor percepatan reaksi (Q10) dengan basis suhu penyimpanan 35 ℃ dan 45 ℃ sebesar 2.17. Persamaan Q10 dengan basis umur simpan pada suhu penyimpanan 45 ℃ (4 hari) digunakan untuk menduga umur simpan pada berbagai suhu penyimpanan. Hasil pendugaan umur simpan menunjukkan hubungan eksponensial umur simpan terhadap suhu. Hasil pendugaan umur simpan pada suhu dingin (10 ℃) dan suhu ruang (25 ℃) berturut-turut adalah selama 60.0 hari dan 18.8 hari.

The shelf life of a product is influenced by several quality parameters simultaneously. Estimating shelf life using the Multivariate Accelerated Shelf Life Testing (MASLT) approach is expected to be able to estimate shelf life more accurately. This study aims to (1) examine the effect of temperature on the quality of lemons, (2) examine the shelf life of lemons with the Multivariate Accelerated Shelf Life Testing (MASLT) approach, (3) estimate the shelf life of lemons at various storage temperatures. Lemons are obtained from farmers in Lembang, West Bandung Regency measuring 132.7 g was harvested at the age of 1 year after flowering. A total of 21 lemons were washed and stored at 25, 35, and 45 ℃. Changes in the quality of lemons were observed every 1 day for 7 days including total dissolved solids, moisture content, firmness, weight loss, and lemon color. Observations at 45 ℃ were stopped when the sample got a hedonic score of less than 2.5. Principal Component Analysis (PCA) was used to reduce many observed lemon quality parameters. The results showed that 91.29% of the variance of all observational data could be explained by the first principal component (PC1). Multivariate kinetics of quality parameter changes following a zero order reaction. The plot of ln km against 1/T shows a multivariate activation energy value (Ea) of 62.99 kJ/mol with a pre-exponential factor (k0) of 3.87 × 1010 PC1 score/day. The reaction acceleration factor (Q10) based on storage temperature of 35 ℃ and 45 ℃ is 2.17. Equation Q10 based on shelf life at storage temperature of 45 ℃ (4 days) was used to estimate shelf life at various storage temperatures. The results of the estimation of shelf life show an exponential relationship between shelf life and temperature. The results of the estimated shelf life at cold temperatures (10 ℃) and room temperature (25 ℃) were 60.0 days and 18.8 days, respectively.