The Torah in Parashat Shemini (Vayikra 11:34) establishes that food can become Tameh (ritually impure) through direct contact with sources of impurity, under certain conditions. First, food is susceptible to Tum’a (impurity) only if it is designated for human consumption. Animal fodder does not become Tameh. Secondly, food is susceptible to Tum’a only if it is no longer attached the ground. Produce which is still attached to a tree or to the ground, even if it is ripe and edible, cannot become Tameh. Finally, food does not become susceptible to Tum’a until it was first moistened by liquid. The Torah states that the food must first have had water fall on it, but the oral tradition teaches that any of the “seven liquids” has the effect of rendering food susceptible to Tum’a. These liquids are commonly represented by the mnemonic “Yad Shahat Dam.” The “Yod” represents “Mayim” (water); the “Dalet” stands for “Dam” (blood)”; the “Shin” refers to “Shemen” (oil); the “Het” alludes to “Halab” (milk); the “Tet” stands for “Tal” (“dew”), the second “Dalet” is “Debash” (honey); and the final letter, “Mem,” refers to the most common liquid – “Mayim” (water). Any of these seven liquids has the ability to be “Machshir” – to “prepare” food for receiving Tum’a. The Sefer Ha’hinuch explains this law by drawing a comparison to the obligation of Terumot and Ma’aserot – the various portions which must be separated from one’s agricultural produce and given to a Kohen or Levi. The obligation of Terumot and Ma’aserot takes effect only at the point of “Gemar Melacha” – when the process of harvesting has been fully completed. Somewhat similarly, the Sefer Ha’hinuch writes, produce attains the status of “food” such that it can become Tameh only after it has been rinsed, as it is only at that point when it is considered edible, since people do not eat produce before first rinsing it. A liquid prepares a food to become Tameh only if the owner specifically wanted it to come in contact with the liquid. The Talmud gives the example of a person who wishes to hide his produce from thieves, and he hides the fruits or vegetables in a bucket of water. This produce came in contact with water, but this was not the owner’s intent; he put the produce in the bucket to hide it, not to rinse it. Therefore, the food is still unable to become Tameh. Additionally, the liquid makes the food susceptible to Tum’a only if the liquid is intended to be used for either cleaning or drinking. If, for example, a person has a leak in his home, and he places a bucket at that spot in order to catch the water so it does not damage his home, the water in that bucket is unable to be “Machshir” food. The person has no intention to use that water for any purpose – for neither drinking nor rinsing – and therefore, it does not have the halachic status of “Mashkeh” that can render food susceptible to Tum’a. If, however, the person placed the bucket where the rain is dripping in order to clean the bucket, then this water is indeed considered a “Mashkeh” and has the ability to render food susceptible to impurity. The Sefer Ha’hinuch notes that this law applies in all places and in all times. Even nowadays, food can become Tameh if the necessary conditions are met, though there is no practical Halachic ramification to this status, since today we in any event do not eat food which is forbidden to be eaten if it becomes Tameh (such as Teruma and the food of sacrifices).