Ninhydrin test, Biuret test, Xanthoproteic acid test and Millon’s test were present in egg albumin and milk. This is essential substances in human body for the maintenances of protein. The normal range for total protein is between 6 and 8.3 grams per deciliter (g/dL).

Ninhydrin reacts with glycine and through a complex reaction forms a purple end product that can be easily visualized. The following organisms are used to determine the performance of the product.

The marker for a positive ninhydrin test is a deep blue colouration obtained in the solution. This reaction indicates the presence of amino acids, other amines and ammonia in the test sample.

Principle of Ninhydrin Test By the end of the reaction, a diketohydrin complex is formed which has a deep purple color. In amino acids like proline and hydroxyproline, this test yields an iminium salt, which is yellow-orange in color.

Ninhydrin (2,2-dihydroxyindane-1,3-dione) is a chemical used to detect ammonia or primary and secondary amines. When reacting with these free amines, a deep blue or purple color known as Ruhemann’s purple is produced.

Ninhydrin Test Almost all amino acids contain a free amino group (except proline and hydroxyproline). Some proteins also give a positive test with ninhydrin.

Ninhydrin Test Result Interpretation For hydroxyproline and proline, a yellow colour is obtained. For asparagine, brown colour is obtained. If no colour change is observed, the analyte does not contain amino acids, amines, or ammonia.

An amino acid has this ability because at a certain pH value (different for each amino acid) nearly all the amino acid molecules exist as zwitterions. If acid is added to a solution containing the zwitterion, the carboxylate group captures a hydrogen (H+) ion, and the amino acid becomes positively charged.

There are six tests for the detection of functional groups in amino acids and proteins. The six tests are: (1) Ninhydrin Test (2) Biuret Test (3) Xanthoproteic Test (4) Millon’s Test (5) Hopkins-Cole Test and (6) Nitroprusside Test.

Theoretically only amino acids produce color with ninhydrin reagent. However, one should always check out the possible interference from peptides and proteins by performing blank tests especially when such solutions are readily available.

Ninhydrin reacts with the α-amino group of primary amino acids producing ‘Ruhemann’s purple’. The chromophore formed is the same for all primary amino acids. The intensity of the colour formed depends on the number and chemical nature of the amino groups being analysed.

The 9 essential amino acids are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Aliphatic Amino Acid Examples Alanine, isoleucine, leucine, proline, and valine, are all aliphatic amino acids. Methionine is sometimes considered an aliphatic amino acid even though the side chain contains a sulfur atom because it is fairly non-reactive like the true aliphatic amino acids.

Amino acids are made up of a central carbon bonded to an amino group (–NH2), a carboxyl group (–COOH), and a hydrogen atom. The central carbon’s fourth bond varies among the different amino acids, as seen in these examples of alanine, valine, lysine, and aspartic acid.

Amino acids function as the building blocks of proteins. Proteins catalyze the vast majority of chemical reactions that occur in the cell. They provide many of the structural elements of a cell, and they help to bind cells together into tissues.

They’re essential because essential (in nutrition) refers to whether or not it can be produced by the body. Many aliphatic amino acids (like isoleucine) cannot be synthesized and must be acquired dietarily.

All nine essential amino acids perform varied roles in your body. They’re involved in important processes such as tissue growth, energy production, immune function and nutrient absorption.

Foods that contain all nine essential acids are called complete proteins. These include eggs, fish, beef, pork, poultry, and whole sources of soy (tofu, edamame, tempeh, and miso). Generally speaking, plant proteins have lower essential amino acid contents when compared to animal proteins.

Milk is considered a “complete protein,” meaning it contains all nine of the essential amino acids necessary for your body to function at an optimal level ( 14 ). There are two main types of protein found in milk — casein and whey protein.

Protein & Other Nutrients in an Egg Adequate dietary protein intake must include all the essential amino acids your body needs daily. The egg boasts them all: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.

Nutrients in milk

• calcium.
• riboflavin.
• phosphorous.
• vitamins A, and B12.
• potassium.
• magnesium.
• zinc.

Although peanut butter is not a complete protein — meaning it does not contain all of the essential amino acids the body needs — it does count toward a person’s daily protein intake.

One avocado contains about 3 grams of protein which, along with bananas, makes it one of the only fruits containing a fairly high amount of protein. Protein builds, maintains and replaces the tissues in your body. In fact, your muscles, organs and immune system are made up mostly of protein.

Peanut butter contains a high amount of calories per serving. Make sure to moderate your portions to avoid unwanted weight gain. While most of the fat in peanut butter is relatively healthy, peanuts also contain some saturated fat, which can lead to heart problems when consumed in excess over time.

Consult your doctor or dietitian if you’re not sure how much PB you should eat, but a good general rule of thumb is around one to two tablespoons a day. Newell said a healthy serving of any high-fat food is roughly two tablespoons.