Karakteristik Fisik dan Kandungan Asam Glutamat Bubuk Tomat dengan Variasi Putih Telur dan Suhu Pengeringan menggunakan Metode Foam Mat Drying

Abstract

Tomato powder is a value-added processed product that extends the short shelf life of fresh plum tomatoes while retaining beneficial compounds such as glutamic acid, the free amino acid responsible for the umami taste of tomatoes. This study examined the effect of egg white concentration (7.5%, 10%, and 12.5% w/w) and drying temperature (50, 60, and 70°C) on the physical characteristics and glutamic acid content of tomato powder produced by the foam mat drying method. A two-factor completely randomized design with two replications was used. Tomato paste was mixed with 20% maltodextrin and egg white as a foaming agent, whipped into a stable foam, dried using a food dehydrator, then milled and sieved through a 60-mesh sieve. The parameters observed were yield, moisture content, solubility, hygroscopicity, color (L* and a*), and glutamic acid content, which were analyzed using ANOVA followed by Duncan's Multiple Range Test. The results showed that increasing egg white concentration increased yield (14.27-17.06%), solubility (53.72-70.16%), hygroscopicity (11.43-12.10%), lightness, and glutamic acid content (0.648-0.866%), but decreased moisture content (7.87-9.02%) and redness. Increasing drying temperature decreased yield and moisture content, increased solubility and hygroscopicity, increased lightness, decreased redness due to lycopene degradation, and slightly increased glutamic acid content due to heat- induced protein hydrolysis. Based on the De Garmo effectiveness test, the combination of 12.5% egg white concentration and 70°C drying temperature produced the best treatment, with an effectiveness value of 0.51, indicating its potential as a natural flavor-enhancing ingredient with an extended shelf life for food industry applications.