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In the food and oil processing industry, maintaining the quality and safety of edible oils is crucial. One of the most significant indicators of oil degradation during use, especially during frying, is the formation of Total Polar Compounds (TPCs) . These compounds play a vital role in determining whether the oil is still suitable for consumption or needs to be discarded. What Are Total Polar Compounds? Total Polar Compounds are a group of substances formed when edible oils are exposed to high temperatures, such as during deep frying. Over time, heat, oxygen, and moisture cause the oil to break down, resulting in the formation of polar substances like oxidized triglycerides, free fatty acids, mono- and diglycerides, and polymerized triglycerides. These compounds increase with repeated oil use and indicate oil degradation, reduced nutritional value, and the potential formation of harmful substances. Why Is TPC Measurement Important? Monitoring TPC levels is essential for both food safe...

Indole Test Procedure: Inoculation: Using a sterile inoculating loop, transfer a loopful of the bacterial culture into a tube of peptone water or tryptophan broth. Incubation: Incubate the tube at 35–37°C for 24 to 48 hours. Addition of Reagent: After incubation, gently add 5 drops of Kovac’s reagent down the inner wall of the test tube without shaking. Observation: Allow the tube to stand undisturbed for a few minutes. A red or pink ring at the top indicates a positive indole test. No color change indicates a negative result. 🎯 Why is the Indole Test Important? Helps identify indole-producing bacteria Used in medical and clinical diagnostics Commonly applied in water and food safety testing #IndoleTest #Microbiology #ScienceExperiment #ChemistryLab 

The Membrane Filter Method is a widely used microbiological technique for detecting and counting bacteria in water and liquid samples. 🔬 Procedure :  Take a measured volume of the sample (usually 100 mL). Pass it through a sterile membrane filter (0.45 µm pore size) using a vacuum pump. Place the filter carefully onto a selective agar plate. Incubate the plate at the required temperature (typically 35–37°C) for 24–48 hours. After incubation, count the colonies that have grown on the filter surface. Calculate the result as CFU per 100 mL of sample.

OXIDASE TEST..... . . . In this short video, we demonstrate the oxidase test  a well-known oxidase-positive bacterium. This test is used to detect the presence of the enzyme cytochrome c oxidase, which is involved in the electron transport chain. 🧪 Procedure: Take a clean, sterile oxidase disc or filter paper. Using a sterile loop or wooden stick, pick a small colony of Pseudomonas from a fresh agar plate. Rub the colony gently on the disc or moistened filter paper. Observe the color change within 10–30 seconds. ✅ Positive Result: A purple or dark blue color appears — indicates Pseudomonas is oxidase positive. 🧫 Test Organism: Pseudomonas spp. 🔬 Application: Biochemical Identification of Bacteria 📍 Category: Microbiology | Biochemistry | Chemistry Practical #Oxidase