EFFECT OF TEMPERATURE AND RH ON THE PHYSICOCHEMICAL PROPERTIES OF WHEY PROTEIN ISOLATE AND COMMERCIAL CITRUS PECTIN CONJUGATES: APPLICATION AS AN EMULSIFIER IN β-CAROTENE O/W EMULSION

SONIA DORA FEBRI ESA, Prof. Dr. Ir. Chusnul Hidayat ; Dr. Arima Diah Setiowati, S.T.P., M. Sc.

2021 | Tesis | MAGISTER ILMU DAN TEKNOLOGI PANGAN

Dry heating treatment (DHT) dilakukan untuk mengkonjugasikan Whey Protein Isolate (WPI) dan High Methoxy komersial Citrus Pectin (HMCCP). Konjugat diharapkan terbentuk melalui reaksi Maillard. Pembentukan konjugat melalui reaksi Maillard dipengaruhi oleh berbagai faktor seperti suhu (T) dan Kelembaban Relatif (RH). Dalam penelitian ini, kami mengevaluasi pengaruh T dan RH pada sifat fungsionalitas konjugat WPI-HMCCP dalam menstabilkan emulsi yang mengandung beta karoten. Konjugat dibentuk melalui perlakuan dry heating pada T 60, 70, 80oC dan RH 60, 70, dan 80%. Ada pembentukan senyawa dengan berat molekul tinggi dalam konjugat pada DHT pada 80 oC dan RH 80% (C8080) sebagaimana dikonfirmasi oleh analisis SDS-PAGE. Peningkatan suhu DHT meningkatkan derajat glikasi (DG) konjugat. Emulsi yang distabilkan dengan konjugat C8080 menunjukkan viskositas terendah. Mengenai stabilitas emulsi yang mengandung beta karoten, beta karoten dalam emulsi yang distabilkan oleh konjugat memiliki stabilitas yang lebih baik daripada yang distabilkan hanya menggunakan WPI murni dan campuran WPI-HMCCP tanpa pemanasan. Hal ini menunjukkan bahwa adanya konjugat dalam emulsi memberikan stabilitas yang lebih baik pada beta karoten.

Dry heat treatment (DHT) was performed to obtain Whey Protein Isolate (WPI)-High Methoxy commercial Citrus Pectin (HMCCP) conjugates. The conjugates were expected to form through Maillard reaction. The formation of conjugates through Maillard reaction is influenced by different factors such as temperature (T) and Relative Humidity (RH). In this study, we evaluated the impact of T and RH on the functionality of WPI-CCP conjugates in stabilizing β-carotene loaded emulsion. The conjugates were formed through dry heat treatment at T of 60, 70, 80 oC and RH of 60, 70, and 80%. There was formation of high molecular weight compounds in the conjugates upon DHT at 80 oC and RH of 80% (C8080) as confirmed by SDS-PAGE analysis. Increasing the DHT temperature increased the Degree of glycation (DG) of the conjugates. C8080 stabilized emulsions showed to have the lowest viscosity. Regarding the stability of the beta carotene-loaded emulsions, beta carotene in the emulsions stabilized by the conjugates had better stability than that in those stabilized by native WPI and mixture of WPI-CCP. It showed that the presence of conjugates in the emulsions provides better stability to the beta carotene.

Kata Kunci : Whey Protein Isolate; Conjugates; Dry Heat Treatment; Emulsion, β-carotene