You can choose any size for your food packaging label, though you have to take into consideration the amount of required information that needs to be printed on it. Each printing press offers some standard sizes that you can choose from, but they can also make custom labels according to your needs.
The same thing applies to your choice of color for the food label. Some printing presses can print labels in as many colors as you want, and some have certain limitations.
When choosing colors for a food packaging label, it is important to remember that the letters need to be clearly typed, readable, and the barcode has to be scannable. That is why the choice of dark colors or a mix of colors that diffuse information is not an option.
Remember that the food packaging label is the first thing a buyer sees on your product. It needs to be eye-catching and more appealing than all the others.