Experimental Study on the Corrosion of Carbon Steel and Aluminum Alloy in Firefighting Protein Foam Concentrates

The corrosion of mild steel and Al alloy in Fomtec P 6% and 6% P Profoam 806 protein-based foam concentrates was investigated. Weight-loss data for steel showed corrosion penetration of 0.745 mipy in Fomtec and 2.269 mipy in Profoam, whereas for Al alloy the penetration levels were 0.474 and 1.093 mipy, respectively. Scanning electron microscopy and energy dispersive X-ray spectroscopy allowed characterization of the metallic surface covered or free from corrosion products. Values of corrosion potential, corrosion current density and corrosion penetration were calculated by using potentiodynamic polarization curves. Electrochemical impedance spectra illustrated the change in polarization resistance during anodic polarization. Data obtained by accelerated electrochemical methods confirm the greater aggressiveness of the Profoam concentrate compared to Fomtec concentrate.

Kinetika Pengeringan Busa Ampas Seduhan Teh

Dominasi produksi minuman teh dalam kemasan berdampak pada meningkatnya produksi limbah ampas seduhan teh yang masih memiliki kandungan berbagai metabolit sekunder, mineral, serat dan protein. Metode pengeringan busa (foam mat drying) dapat diterapkan pada produksi serbuk ampas seduhan teh guna mendukung pengembangan dan pemanfaatan lebih lanjut dari ampas seduhan teh. Tujuan penelitian ini adalah mengkaji pengaruh penambahan konsentrasi busa putih telur pada proses pengeringan busa ampas seduhan teh serta mengkaji kinetika pengeringan lapis tipis menggunakan model kinetika Newton/Lewis, Page, Henderson-Pabis, Logartitmic dan Two Term. Parameter proses yang dievaluasi meliputi variasi penambahan busa putih telur (7,5-15%) sementara kadar maltodekstrin yang ditambahkan sebesar 30% dan pengeringan dilakukan pada suhu 800C. Penelitian menunjukkan jika penggunaan busa putih telur 7,5% memberikan kontanta kecepatan pengeringan yang lebih tinggi bila dibandingkan penggunaan busa putih telur 10-15%. Dalam penelitian ini, model kinetika Page merupakan model yang memberikan kesesuaian yang lebih tinggi bila dibandingkan dengan model kinetika Newton/Lewis, Henderson and Pabis, Logartitmic dan Two Term. The emerging growth of tea based beverage impacts on the abundance of spent tea waste, a solid waste in which rich of secondary metabolites, minerals, fibre and protein. Foam mat drying of spent tea leaves powder is applied for further utilization of spent tea waste. The objective of this research was to investigate the influence of egg white concentration added in the foam mat drying of spent tea waste and investigate the foam mat drying kinetics. The thin layer drying kinetics models applied were Newton/Lewis, Page, Henderson-Pabis, Logartitmic and Two Term model. The egg white concentration were varied of 7,5-15%, meanwhile the maltodextrin was of 30% and the the drying processes were performed at temperature of 800C. The research showed that the foam mat drying of spent tea waste performed at egg white concentration addition of 7,5% gave higher drying rate constant. In this research, Among the empirical models applied in this research, Page model was found to be the most adequate model representing the drying behavior of spent tea waste.

The Foaming Properties of Skim Milk Protein Concentrate

Aerated products are popular all over the world, especially those with a foam structure. They are widely represented in the range of the global food market, including that of the Russian Federation. Traditionally, milk proteins are added to stabilize various foods. The present research explains how the concentration of skimmed milk proteins affects the foaming properties of concentrates. The experiment featured the influence of various protein concentrations (from 3.4 to 16.0%) on the foaming properties of reduced skim milk (9.2%) and of milk protein concentrates obtained by ultrafiltration. The research established their practical application for aerated products. The quality of protein foam was evaluated by foaming characteristics and foam stability. The distribution of protein foam bubbles by size was modelled using Erlang distribution. According to the simulation, the foams of protein solutions with a concentration of 12% were more stable. Concentrates with the highest protein content (16%) had not only a greater foaming, but also a greater stabilizing property. The protein samples density increased together with protein concentration. Similarly, the foaming characteristics of protein solutions (multiplicity and density of the foam) increased together with protein concentration. The stability of the foam structure was estimated by the half-life of the foam volume and the average diameter of the foam bubbles in the protein solutions. The most stable foams were those with the highest protein content in the concentrate. The protein concentrates from reduced skim milk were inferior in foaming characteristics to concentrates from milk that was not subjected to drying. However, the results suggest that the reduced skim milk and its protein concentrates are ideal for the production of aerated dairy products because they provide both good foaming and stability.