Does the law require me to present the ice cream composition to my customers?

Yes. The guidelines are very specific, and improperly preparing such a list may result in a heavy financial penalty from Sanepid or the Agricultural and Food Quality Inspection. This is detailed in §19 paragraphs 1 and 2 of the Regulation of the Minister of Agriculture and Rural Development dated December 23, 2014, on the labeling of various food products. It states that for food products offered for sale to the final consumer (...) without packaging or in the case of packaging food products in the sales area at the request of the final consumer (...) the following must be provided: the name of the food product, the name or the first and last name of the producer, and a list of ingredients—according to Articles 18-20 of Regulation No. 1169/2011. (Always in the decreasing order of their mass at the time of use when producing the product). This information is provided in the sales area on a display concerning the food product or in another way that is accessible directly to the final consumer.