From my point of view, this all has to do with purpose. If you want your customers to find anything related to their search phrase without informing them of the price, the default e-commerce will do. If you have several products that only differ in quality, leaving out the prices and make the customer decide based on images, might raise income. Displaying all the prices, let's the customer compare on price base. This might cause the cheaper products to be bought more often.
If you're comparing prices against several shops, a price is indeed very important to display. If you're only selling products based on specific taste or origin, people won't make choices based on price. Their either looking for taste, quality, origin, color or anything else that could be food related.
Adding the prices on the products seems to be useful for comparison, but not specifically to the product itself. If people search for a specific product and they see all kinds of high prices come by of other products, people might expect the product they're looking for to be of a high price as well.
So.. Why would your users use the search function and what is the benefit they should receive from searching with the form? What are the most important specific values of the products and what's the best way to display this information?
If your price is important, then you could display it. Wager the pros to the cons to decide what would be better.