Determining Protein Content of Protein Supplements and Determining Genuine or Counterfeit Protein Supplements with a Novel Consumer Friendly Kit

Abstract

The present invention relates to a user friendly and cost effective kit for determining the protein content in protein supplements and determining if the protein supplement is a genuine or a counterfeit protein supplement in a home setting. Furthermore, the present invention also details the method of using the kit.

Claims

1. A kit for quantitative measurement of for determination of protein content in a protein supplement wherein the kit comprises: a graduated tube with markings to measure the amount of precipitate; a non-graduated tube containing the protein precipitation solution; and a protein measurement chart with precipitate volume in millilitres indicating corresponding amount of protein as percentage.

2. The kit according to claim 1, wherein the protein precipitation solution contains trichloroacetic acid (TCA) in an amount of 30% w/v.

3. A method of using the kit according to claim 1, wherein the method of using the kit comprises: dissolving/suspending the measured quantity of the protein supplement in a fixed quantity of water in a container, taking a fixed portion of the above solution/suspension in a graduated tube and adding the protein precipitation solution and shaking the contents for a fixed amount of time, leaving the graduated tube on standby overnight, measuring the level of precipitate in the graduated tube based on the markings; and tallying the corresponding precipitate volume from the protein measurement chart and calculate the percentage of protein.

4. The method of using the kit according to claim 3, wherein the quantity of water is about 200 Ml.

5. The method of using the kit according to claim 3, wherein the the final volume of the protein precipitation solution is made up to 100% with water.

6. The method of using the kit according to claim 3, wherein the method is performed by the consumer in a home setting.

7. The method of using the kit according to claim 3, wherein the graduated tube with precipitate is inverted, observing if the precipitate remains intact and does not fall down within a few seconds or the whole precipitate does not mix with the solution and concluding that the protein supplement is a genuine protein supplement; or observing if the precipitate re-disperses and mixes with the contents of the graduated tube and concluding that protein supplement is a counterfeit protein supplement.

8. The method of using the kit according to claim 5, wherein the precipitate is scooped out of the graduated tube by a spatula or a spoon like device and observing if a thick and uniform precipitate comes out, concluding that the protein supplement sample contains genuine protein; or precipitate is scooped out of the graduated tube by a spatula or a spoon like device and observing if precipitate comes out as a watery precipitate rather than a thick uniform paste, concluding that the protein supplement sample is a counterfeit protein supplement.

9. The kit according to claim 1, wherein the protein supplement is a whey protein supplement.

10. The method according to claim 3, wherein the protein supplement is a whey protein supplement.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0053] The present invention provides a method and a kit for quantitative determination of protein content in a protein supplement such a whey protein supplement. The method works on the principle of hydrophobic aggregation in which the protein precipitation solution precipitate outs the protein present in the protein supplement such as whey protein. The protein precipitation solution is a ready to use solution packed in a suitable container for use by the consumer to test the protein supplements in an environment that does not require sophisticated instruments and costly reagents of an analytical laboratory. The protein precipitation solution is prepared by dissolving a weighed quantity of trichloroacetic acid in an amount of water and making up the desired volume with water. For example, to make 100 mL of the protein precipitation solution, about 30 grams of trichloroacetic acid is dissolved in 50 mL of water. Optionally, to this solution 10 mL of ethanol is added and the final volume of 100 mL is made with water. Ethanol if used can be present in an amount of about 5% to 20%, preferably about 10%. The solution can then be packed in the form of kit. The kit may comprise of a container containing the protein precipitation solution and a graduated container such as a centrifuge tube or a graduated tube. The kit can optionally also contain a shaker for preparing the solution/suspension of the protein supplement in water. Alternatively, the consumer can use any suitable container readily available to prepare the solution/suspension of the protein supplement.

[0054] The protein precipitation solution is effective at lower amounts than the other precipitation reagents ~30% for TCA helps to denature the protein. Further, it does not affect total protein content in the sample and the precipitate can be further analyzed by standard methods. The method precipitates the proteins independently of their physicochemical properties.

[0055] The method is further made easy to perform with the help of the kit. The kit comprises a graduated tube with markings to measure the volume of precipitate; a non-graduated tube or a vial containing the protein precipitation solution; and a protein measurement chart indicating precipitate volume in millilitres and its corresponding amount of protein as percentage. The graduated tube may have a length of about 120 mm and a diameter of about 25 mm with 1 mL least count. The non-graduated glass tube or vial may contain about 30 mL to 40 mL of protein precipitation solution, preferably 35 mL.

[0056] Further, the method can also be used to test whether the protein supplement is a genuine protein supplement or a counterfeit supplement. For example, after measuring the precipitate volume, the graduated tube can be inverted to observe if the precipitate remains intact and does not fall down or the whole precipitate does not mix with the solution. If so observed then it can be concluded that the protein supplement sample is a genuine protein supplement. If it is observed that the precipitate mixes in a few seconds or the whole precipitate mixes with the contents of the tube then it can be concluded that the protein supplement sample is a counterfeit protein supplement. Alternatively, the same method can be followed by using a spatula or a spoon like device. The precipitate is scooped out of the graduated tube by a spatula and if a thick and uniform precipitate comes out, then it can be concluded that the protein supplement sample contains genuine protein supplement. If the precipitate comes out as a watery precipitate rather than a thick uniform paste, then it can be concluded that the protein supplement sample is a counterfeit protein supplement.

TABLE-US-00001 Protein Measurement Chart S. No. Precipitation (in mL) Corresponding Protein Content (%) 1 6 mL - 7 mL 35-45 % 2 7 mL - 8 mL 45-55% 3 8 mL - 9 mL 55-65 % 4 9 mL - 10 mL 65-75% 5 10 mL - 11 mL 75-85 % 6 >11 ml More than 85 %

[0057] The method can be performed by steps as follows: [0058] 1. Take 30 g of protein supplement powder in 200 ml of drinking water (8-15° C.) in a Shaker bottle and mix the protein supplement powder with manual shaking for 15 to 30 seconds; [0059] 2. In a graduated tube add 35 mL of protein precipitation solution. [0060] 3. To the above graduated tube add 10 mL of the protein powder solution/suspension of step 1. [0061] 4. Shake the graduated tube for 60 seconds and keep it in vertical position overnight at room temperature. [0062] 5. Measuring the precipitate volume in the graduated tube and tallying the corresponding volume from the protein measurement chart indicating corresponding amount of protein as percentage.

[0063] The same test kit can also be used to determine if the protein supplement sample is genuine or a counterfeit supplement. The method can be performed after the protein precipitation solution and the protein powder solution/suspension have been mixed in the graduated tube as that in Step 4 above. If about one minute of mixing, some precipitate will float at the top of the solution, while some precipitate will start settling at the bottom of the tube as a coagulate i.e. the supplement tested contains protein such as a whey protein. If mixture is uniformly spread out in the same colour as of the initial dispersion that was poured, without any separation or precipitation at all, it is the first indicator that the tested protein supplement could actually be a counterfeit. It could be a flour with maltodextrin - some kind of carbohydrate or even a non-food item. After five minutes, if there is even more separation of the precipitate settling at the base of the tube as a coagulate and the precipitate floating at the top of the tube becomes thinner and the solution in the middle starts to become clearer it can be concluded that supplement tested does contain protein and is a genuine protein supplement. In another scenario, after five minutes, the mixture is still uniformly spread out in the same color with not much difference from the first observation five minutes earlier and is still without any separation or precipitation, it can be concluded that the supplement tested is counterfeit protein supplement.

[0064] The test method of the invention can check the amount of protein in any protein sample and several marketed whey protein supplement products were tested by this novel method. Table 2 provides the results of testing the protein content of some commercially available protein supplements.

[0065] All the results were confirmed in the Laboratory through quantitative analysis of the same samples using standard Kjeldahl method for protein content. The recovery for the entire sample was found to be approximately 95% as per the label claim.

[0066] This method is fast, reliable and consumer friendly which can be done at home using the kit. The purpose of this study was to transfer the complex laboratory method to the consumer’s home where anyone can test the quality and genuineness of the protein supplements. This way consumer can become more aware and confident of the quality of the protein supplement such as whey protein they have purchased from the source.

TABLE-US-00002 Protein Content of Some Commercial Protein Supplements Determined by the Protein Precipitation Method Using the Kit of the Invention. Products (80%) MB Raw Whey® MB Beginner’s Protein® Pro Burst® MB Biozyme Whey® MB Whey Gold® Approximate Protein Content by standard method 80% 40% 73% 76% 83% Over night results >11 mL 6-7 mL 9-10 mL 10-11 mL 10-11 mL Determined Content (Kjeldahl method) 80%+ 40% 73% 75+% 80+%