Economy of Iran spices including cumin and sumac. Iran is the world's largest producer of saffron, pistachios, honey, berberis and berries and the second largest date producer. Meat and dairy products include lamb, goat meat, beef, poultry, milk, eggs, butter, and cheese. Non-food products include wool, leather, and silk. Forestry products from the northern slopes of the Alborz Mountains are economically important. Tree-cutting is strictly controlled by the government, which also runs a reforestation program. Rivers drain into the Caspian Sea and are fished for salmon, carp, trout, pike, and sturgeon that produce caviar, of which Iran is the largest producer. Since the
Saffron per gram, given the wide possible range of colouring strengths that different kinds of saffron can have. Despite attempts at quality control and standardisation, an extensive history of saffron adulteration, particularly among the cheapest grades, continues into modern times. Adulteration was first documented in Europe's Middle Ages, when those found selling adulterated saffron were executed under the "Safranschou" code. Typical methods include mixing in extraneous substances like beetroot, pomegranate fibres, red-dyed silk fibres, or the saffron crocus's tasteless and odourless yellow stamens. Other methods included dousing saffron fibres with viscid substances like honey or vegetable oil to increase their weight.