Drying Yerba Mate
In Paraguay, all yerba mate is dried the same way. The recently harvested yerba mate is placed on a conveyor belt which carries it to a long spinning metal drum. While in the drum, the yerba mate is flame-dried for a maximum of 30 seconds, after which it is passed onto another conveyor belt and carried to a storage room for subsequent grinding and aging. Burning different types of wood to dry the yerba mate can affect its taste and smell greatly. This is why some yerba brands have a very "smokey" flavor. La Rubia uses only one type of wood in their oven which gives their yerba mate its unique taste.

Argentinian yerba mate has a very distinct taste which could be attributed to the practices used to dry their yerba mate. Some manufacturers place their yerba mate in a large oven after harvest and is "slow-roasted" for up to 45 days. This, in theory, gives the yerba mate a flavor as if it has been fired and aged for one year or more. However, this practice wouldn't allow the chemical components in the leaves to breakdown which could leave the yerba mate with a bitter taste. One can liken yerba mate to wine: its taste gets better with age.

Grinding Yerba Mate
Most, if not all, companies grind their yerba mate in the same manner. Some companies try to minimize the amount of yerba mate powder in their finished product while others include it in their product in order to maximize their finished product yields. Having a powdery yerba mate will allow much of it to be sucked up through the bombilla during consumption. Moreover, the taste of a powdery yerba mate will not last as long as it would otherwise.

Aging Yerba Mate
Yerba mate needs to age in order to allow the chemical bonds in the leaves to breakdown, minimizing the natural bitterness of the plant. As a general rule, most companies in Paraguay allow their yerba mate to age for 1-2 years. In Argentina, companies age their yerba for 1 year or less. Each method is an acceptable way of yerba mate manufacturing, however, they do result in different bitterness levels, as mentioned above.

Cutting Yerba Mate
Adding leaves and stems from trees other than yerba mate is not uncommon, however it can be detrimental to yerba mate taste and, in worse cases, health of the consumer. Some companies have been known to "cut" their yerba mate with leaves from laurel or other native trees in order to increase their end-product volume. One brazilian company actually added mango leaves to their yerba mate and made many people sick (mango is in the poison ivy family-Anacardiaceae).