Produksi dan Karakterisasi Fisikokimia Konsentrat Protein dari Okara

Abstract

Pemanfaatan limbah padat tahu/ampas tahu (okara) belum optimal meskipun memiliki kandungan gizi yang cukup baik, hanya digunakan sebagai pakan ternak dan sebagian dibuang menyebabkan potensi pencemaran lingkungan. Penelitian ini bertujuan memproduksi dan mengkarakterisasi protein yang diperoleh dari okara dalam bentuk konsentrat protein kering. Analisis yang dilakukan, yaitu proksimat, komposisi asam amino, kapasitas antioksidan, densitas kamba, Water-Holding Capacity (WHC), Oil-Holding Capacity (OHC), gugus dan struktur sekunder protein, serta flow behavior. Konsentrat protein diperoleh melalui kombinasi metode Alkaline-Assisted Extraction (AAE) dan Ultrasound-Assisted Extraction (UAE) yang diberikan pada sampel secara bersamaan, menghasilkan konsentrat dengan kemurnian 60,18% serta kandungan lemak sebagai impuritas utama (18,98%). Profil asam amino menunjukkan keberadaan seluruh asam amino esensial dengan beberapa di antaranya berperan sebagai asam amino pembatas, serta asam amino umami dengan nilai Taste Active Value (TAV) sebesar 113,52. Okara Protein Concentrate (OPC) memiliki nilai WHC dan OHC yang hampir seimbang dengan kecenderungan hidrofobik. Analisis gugus mengidentifikasi gugus amida A, I, II, dan III secara jelas dengan struktur sekunder protein OPC didominasi oleh struktur ß-sheet. OPC menunjukkan sifat non-Newtonian pseudoplastik (shear-thinning). Optimalisasi dalam proses defatting dan isolasi protein perlu dilakukan untuk meningkatkan fungsionalitas OPC serta kemurnian hasil yang lebih baik.

The utilization of solid waste from tofu/tofu pulp (okara) has not been optimal despite its good nutritional content. It is only used as animal feed and some of it is discarded, causing potential environmental pollution. This study aims to produce and characterize protein obtained from okara in the form of dry protein concentrate. The analyses conducted include proximate analysis, amino acid composition, antioxidant capacity, bulk density, Water-Holding Capacity (WHC), Oil-Holding Capacity (OHC), protein groups and secondary structures, as well as flow behaviour. The protein concentrate was obtained through a combination of Alkaline-Assisted Extraction (AAE) and Ultrasound-Assisted Extraction (UAE) methods applied to the sample simultaneously, resulting in a concentrate with a purity of 60.18% and fat content as the main impurity (18.98%). The amino acid profile showed the presence of all essential amino acids, some of which acted as limiting amino acids, as well as umami amino acids with a Taste Active Value (TAV) of 113.52. Okara Protein Concentrate (OPC) had nearly balanced WHC and OHC values with a hydrophobic tendency. Group analysis clearly identified amide groups A, I, II, and III, with the secondary structure of OPC protein dominated by ß-sheet structures. OPC exhibits pseudoplastic non-Newtonian properties (shear-thinning). Optimization in the defatting and protein isolation processes is necessary to improve the functionality of OPC and achieve better purity of the final product.