Utilize the input text as a context reference, choose the right relationship between milking and milk from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

He has now invested millions of shillings in an ultra-modern structure that has a mechanised milking parlour, a milk processing zone, a laboratory and display unit for processed products.

Answer: product_or_material_produced