There is a producer or manufacturer of a product then there is a seller who sells the product. When a product is manufactured by a company, brand, or business and the same product is sold by any other company, brand, or business under their name then such products are called private label food products. Now before as a consumer or a retailer or a seller you skip a beat, it is important to understand that this is perfectly legal and has been done for a long time just not many people know about it as they never looked into it. Some of the greatest examples of private labels are Nike, H&M, and Zara.
Quality control of the product is done by the seller brand, which is necessary for them to be at the top in the business. In many industries from food to clothing, private label products are available and they are trusted & used by many consumers.
If one wants to start a private label then the first thing to be done is to find a manufacturer. The quality control and other stuff can be handled along the way. The most important part is to sell the product, and brand recognition is required for this. If one is looking to build a brand then it may be a little difficult as it costs to put advertisement and promotion out.
It is easier for an established brand to private label food manufacturers as it has a built customer base that will help in selling the product.