THE LAWS OF SHABBAT

By Rav Yosef Zvi Rimon

Shiur #06: BORER (Part 6)

XII) Filtering Liquids:

The Melakha of Merakked

Is it permissible to use a faucet with an attached filter or a water-purification system on Shabbat?  Is one allowed to use a tea strainer or a teabag?  Is it permissible to separate vegetables from soup by holding the spoon next to the side of the pot?  Is one allowed to use a lettuce dryer?

Defining the Melakha of Merakked

As we have seen in previous shiurim, the melakha of merakked^[1] (sifting) is classically done with a sieve: while the fine flour falls through the sieve’s holes, the bran remains in it.  Merakked is thus similar to borer in the aim of removing pesolet (refuse) from okhel (food), but it is accomplished with a keli, a utensil, vessel or tool.  The Gemara (138a) explains in the name of Rabbi Zeira that one who strains liquids violates this melakha.  According to Rabbi Zeira, any process which separates pesolet from okhel so that the pesolet remains in its place and the okhel falls out (e.g., straining liquid) is forbidden because of the melakha of merakked.^[2] 

However, although it is forbidden to filter liquid with a strainer on Shabbat, there are other ways to bring about this result.  The mishna (139b) allows one to strain wine through a cloth: "Water may be poured over lees [dregs of grapes] in order to dilute them, and wine may be strained through cloths or an Egyptian basket."  A sudar is a cloth which is not designed for filtering but which can be utilized for this purpose, and the same is true of an Egyptian basket, made of palm twigs.  The Amora Ze'iri, in the Gemara (ibid.), even allows for the use of a strainer, which is designed specially for filtering: "A person may put clear wine or water into a strainer on Shabbat without concern, but not cloudy [liquids]."  Under what conditions may one strain wine with a strainer, and when is it permissible to strain only with a cloth?  The Ran (57b, Rif) explains:

[Using] the cloths and the Egyptian baskets...  and everything of this ilk is an alteration, since one is not straining with a strainer.  The cloudy wine discussed here is still drinkable; if it were clear wine, even using a strainer would be permissible, as is stated in the Gemara; and if it is cloudy wine which is undrinkable, even [using] cloths or an Egyptian basket would be forbidden, because it would be borer regardless.

According to this, clear water or wine may be filtered even with a strainer (as Ze'iri states); somewhat cloudy water or wine (as long as it is still drinkable) may be filtered only with a cloth and the like (as the mishna states); while extremely cloudy water or wine (which is undrinkable) may not be filtered at all on Shabbat.  The Ran goes on to explain that if a majority of people would drink the water or the wine as is, the liquid is considered clear and it is permissible to filter it with a strainer, even if there are some debris inside.  However, if a majority of people would not drink the water without filtering, one may not use a utensil designed for straining; one may only use a vessel or utensil which is not designed for filtering, such as a sudar.

If so, according to the Ran, there are three levels.  The Rashba (ibid.) takes a similar approach to the Ran. On the other hand, the Rambam (8:14) understands the Gemara differently:

One who filters wine or oil or water or other liquids with the appropriate strainer is liable... but one may filter wine with no lees or clear water using cloths or an Egyptian basket, so that [the wine or water] will become extremely clear. 

According to him, one is allowed to filter only clear wine or water, and only with a cloth.  One is forbidden to filter liquids which are not clear, and there is no allowance in any case to filter to use a normal strainer.

If so, the Rambam allows filtering clear liquids with a cloth, while according to the Rashba and the Ran one is allowed to filter clear liquids even with a strainer, while with a cloth one is allowed to filter even somewhat cloudy liquids. 

The Tur (Ch. 319) agrees with the Rashba when it comes to clear water, permitting even the use of a strainer, but he agrees with the Rambam when it comes to somewhat cloudy water, and he forbids using even a cloth.

The Shulchan Arukh (319:10) cites both opinions regarding the filtering of clear water (without addressing somewhat cloudy water):

Clear wine or water may be filtered through a strainer...  And according to the Rambam, filtering with a strainer is forbidden — even for clear water or wine.  Even [using] cloths is permitted only with clear liquids, but not with cloudy ones.

If so, the Shulchan Arukh starts by ruling according to the view of the Rashba and the Ran — that one is allowed to filter clear water even with a strainer — without attribution, and after that he notes that the Rambam forbids it.  From his language, it appears that he rules in accordance with the first view.  The Mishna Berura (41) indeed writes that "the law is in accordance with the first view."  (However, some Yemenites are stringent, in accordance with the view of the Rambam.)

Nevertheless, the Mishna Berura adds (42) that one may be lenient when it comes to filtering clear water with a strainer, but "not with cloudy [liquids] — that is, even a bit cloudy," explaining that "in this matter, it is appropriate to be concerned about the words of the Rambam." 

In the Sha'ar Ha-tziyun (34), he explains that in this case other halakhic authorities (such as the Tur) agree with the Rambam, and therefore one should be concerned about their view.^[3]  

Permitting the Filtering of Clear Liquids

Why is one allowed to filter clear liquids (in a strainer, according to the Rashba and the Ran; in a cloth, according to the Rambam)?

The simple explanation is that since the majority of people drink the water even without the filtration, the filtering does not constitute a tikkun (a significant repair or improvement).  Rashi indicates the same.  The Gemara below says that fresh wine, which has just come out of the press, may be filtered even with a strainer, and Rashi (s.v. Bein Ha-gittot) writes:

All wines are cloudy, and they are drunk with the lees; therefore there is no tikkun here, because it is drinkable regardless. 

In other words, since people will drink the wine without filtering, the filtering is not a tikkun.

It should be noted that this explanation is reasonable for those who maintain that the basis of the prohibition of borer is tikkun okhel, improving the food.  As was explained in earlier shiurim, others maintain that the prohibition of borer stems from the fact that one removes pesolet or separates pesolet and okhel, and if so, why is one allowed to filter clear water?  At the end of the day, even in this water, some pesolet is removed (otherwise, one would not filter at all!)

It appears that one could justify filtering clear liquids in another way: since most people drink the water in this way, the water and the debris are considered to be one type, and therefore there is no bereira in this (as we have seen in earlier shiurim, there is no prohibition in the bereira of one type).

Two Types of Food

However, the Tehilla Le-David (319:15) questions this:

This law requires some explication.  Apparently, even if we say that [the debris] is not considered pesolet because [the liquid] can be drunk regardless, nevertheless, it should make no difference!  Since one does not want to drink the debris, it should be like two types of food: whatever one does not want to consume now is called pesolet.

In other words, if we allow a mixture to be separated into its constituent elements whenever the mixture is edible in its commingled state, why is there a prohibition to separate two types of food?  Generally, the two types of food can be eaten when they are commingled; nevertheless, we have determined that if, at the moment, one does not desire one of the types, it is considered pesolet, and there is no permission to separate it!  Why do we not say this concerning one who does not want debris in the water? 

An answer to this question can be found in the Shevitat Ha-Shabbat (Merakked, Be'er Rechovot, 26), who indicates that this allowance is applicable also to two types of food: "Straining the sauce from latkes or vegetables appears to be permissible, since they are eaten like this."  According to him, it is permissible to separate vegetables from broth even with a colander, since many people eat the broth and the vegetables together; consequently, the mixture of vegetable soup is considered like clear water, as it can be consumed without any filtering.  According to this, just as it is permissible to separate a mixture which is edible in its commingled state, one is allowed to separate a mixture of two types of food!

Yet, Rav S.Z. Auerbach (cited in Shemirat Shabbat Ke-hilkhata, Ch. 3, n. 156) disputes this claim:

This approach is only applicable to debris...  which has no significance on its own.  Therefore, since most people drink wine with the lees, they are insignificant in relation to the wine and are considered of one type, so that it is not considered borer...   This is not the case with two significant types, because neither nullifies the other; if, in such a case, one wants to eat only one type, the mere fact that it is possible to eat them together does not permit one to apply this principle.  Therefore, one is liable for borer of two types...  and this resolves the question of the Tehilla Le-David.

This means that the debris, because it is insignificant, is considered to be of the same type as the water, so that borer cannot apply when one removes the debris.  In, for example, vegetable soup, the broth and the vegetables are two types, each of which is significant in its own right; although people customarily eat them together, their separation is a violation of borer.^[4]

Summary

In conclusion, two types of food that are commingled (each type being significant in its own right, e.g., vegetable soup) may not be separated with a strainer, even if most people generally eat them together; but clear liquids, which most people would drink without filtering, may be filtered even with strainer.  Cloudy liquids which most people would not drink (though they are potable) may not be filtered with a strainer; it is preferable not to filter them at all, even though there are those who are lenient and allow one to filter with a keli not designed for this purpose.

A Filter on a Faucet

A sink with a built-in filter on the faucet seems to bring us once again to the dispute among the Rishonim, as generally we are dealing with potable tap water which is being put through a filter: the Rambam would forbid it, while the Rashba and the Ran (whom we follow) would permit it.  This is what the Chazon Ish (53, s.v. Ve-im) indicates:

If a filter hangs from the faucet in order to remove the sand from the water, it is permissible to use it if most people would not avoid drinking unfiltered water...  But if there is a great amount of sand, so that the majority would not drink [the water] unfiltered, it is forbidden.

If so, a filter on a faucet or a water-purification system would pose a problem on Shabbat only if the local water is avoided by most people.   

However, the Minchat Yitzchak (Vol. VII, Ch. 23) writes that even in such a case, one may be lenient:

However, it appears that in our case, because the filter is permanently attached to the faucet, and there is no way for the water to come out of the faucet except via the filter...  We should say that since all of the water passes this way — even the water used for washing hands and dishes comes through this filter — and one is not doing any new act to prepare the water for drinking, this should be no less than the law of bereira by hand, which is allowed when one takes okhel from pesolet in order to eat immediately...  Know that if it were not so, life would be impossible, because, even setting aside the filter on this faucet, the municipal water goes through many filters before it enters the pipes in one's house, and without that filtering it would not be possible to drink the water.  Consequently, even if one would not put a filter on this faucet, it would be forbidden to take water from any faucet on Shabbat.  One is compelled to explain as we have above! 

However, it is not clear that this reasoning would apply to a water-purification system, especially one dedicated to drinking water.  Therefore, one should use such a system only when most people would drink this water without purification (and on the condition that there is no electrical circuit completed each time one uses it).  If this water is not potable without purification, one may not use such a system on Shabbat.^[5]

The Fastidious

The Bei'ur Halakha (319:10, s.v. Ho'il) writes:

If one is fastidious and unable to drink [water] filled with debris and the like, even though most people are not bothered by it, we do not disregard this person's view, and for this person it is forbidden because it is borer. 

According to this, a fastidious person (one who normally insists on filtering water) may not filter water on Shabbat, and this is the view of Rav Elyashiv (cited in Orechot Shabbat, Ch. 3, n. 37).  However, Rav Karelitz (cited ibid., n. 38) maintains that the Bei'ur Halakha's stringency applies only to noticeable pesolet; one may be lenient when it comes to our tap water, which does not contain noticeable debris.

In conclusion, one may use a filter attached to one's faucet.  One may also use a water-purification system (as long as there is no electrical circuit completed in order to get the water out), on the condition that most people drink the local water without filtering.  If this is not the case, one should filter the water before Shabbat.  One who seeks to be lenient despite this should first let some water go to waste or use it for washing, and only subsequently fill the cup with drinking water.

A Tea Strainer

In some teapots, there is a built-in strainer over the spout.  This prevents the tea leaves, which are on the bottom, from being poured off with the liquid when one pours out the last drops.  May one use such a keli on Shabbat? 

Let us consider the ruling of the Shulchan Arukh (319:14) concerning a container of wine with lees at the bottom:

One may pour gently from one keli into another, as long as, when the flow comes to an end and a few drops come out of the pesolet [the lees], one does not remove them [the lees].  If one does not do so, these drops prove that it is borer. 

The Shulchan Arukh allows this because the wine on top is not commingled with the lees, so that one does not violate bereira simply by pouring off.  Similarly, as long as there is a lot of tea in the teapot, there is no problem presented by the strainer when pouring from the teapot, since the tea on top is not mixed in with the leaves and does not require filtering. 

However, when there is only a bit of tea left, it would ostensibly be forbidden to pour it out; as the Mechabber writes, once the flow comes to an end and only a bit of wine is left commingled with the lees, one may not pour the last drops of wine into another keli, since one is selecting the wine from the lees.  Granted, the Mishna Berura there (55) writes that if one drinks the wine immediately, it is permissible to pour out the last drops, but this applies only if one is pouring from one utensil to another without a strainer, so that the bereira of okhel from pesolet is by hand and for immediate use; but when there is a strainer, this is bereira with a keli, which is forbidden even for immediate use, as the Mishna Berura himself writes:

He is talking about one who wants to drink later, for if one wants to drink immediately, have we not established that selecting okhel from pesolet, when done without a keli, is permissible, if one's intention is to consume it immediately?  Here, even though one pours from one keli to another, nevertheless, the essence of the bereira is done by hand.  If one puts wood chips in the spout of the keli into which one is pouring so that [the liquid] will be well-filtered, one must stop when the last drops start coming out — even if the intent is for immediate use — because this is borer by way of a keli. 

It would stand to reason that using a teapot with a strainer is equivalent to putting wood chips in the spout of the vessel, and the matter is considered bereira with a keli and is forbidden (if there is only a bit of tea remaining in the vessel).

However, the Chazon Ish (53, s.v. Min Ha-amur) is inclined to permit using a tea strainer, even if there is only a bit of tea left:

However, it is possible that since there is no use of an actual sifter, even though there is inside, by the spout of the keli, a network which keeps the leaves out, one may say nevertheless that it is nothing more than bereira by hand, which is permissible when one takes okhel from pesolet in order to consume immediately. 

Why does the Chazon Ish claim that using a strainer is considered bereira by hand?  We may explain this according to the view cited in Shemirat Shabbat Ke-hilkhatah, Ch. 3, n. 125, that a keli designed for bereira for immediate use is not included in the prohibition of selecting with a keli:     

I heard from Rav S.Z. Auerbach... that it is possible that a keli designed specifically to select for immediate use is not included in the prohibition to select with a keli... as it is permitted to select by hand because of the reason that this is derekh akhila; it is also permitted for this reason to use a knife even to peel pesolet from okhel...  It is the same in our case: we may say that one is allowed to select with a keli which is always employed for immediate use.

According to this view, one may say that since the teapot is always used for drinking right away, using it is considered bereira by hand, as opposed to a normal strainer or even a spoon, which is at times used to select for later use, so that utilizing it is considered bereira with a keli.

However, there are Acharonim who are stringent in this matter, and they forbid using a teapot with a built-in strainer when there is only a bit of tea left.  This is what the Chayei Adam (16:9) rules, as does the Kaf Ha-chayim (319:113):

It appears to me that on Shabbat it is forbidden to pour the tea out through the abovementioned perforated spout, because this is filtering the tea via the abovementioned spout, and since the spout is made for this purpose, so that the tea will be filtered, this is borer by way of a keli, which is forbidden even to drink it immediately...

This Shevet Ha-levi (Vol. I, Ch. 84),the Berit Olam (Borer, 40-44) and others also rule to this effect.  The Az Nidberu (Vol. I, Ch. 23) suggests that the Chazon Ish's intent is not actually to permit using such a teapot but merely raises the possibility for consideration.  However, the Orechot Rabbeinu (Vol. I, p. 150) cites that both the Chazon Ish and the Kehillot Ya'akov would use such a receptacle without checking how much tea was left.

The Shevitat Ha-Shabbat (Borer, Be'er Rechovot, Ch. 49) justifies the common custom to use a teapot with a built-in strainer in another way: "because it is drunk in this way [separating the leaves from the tea], even if the leaves are still there, by filtering through one's teeth."  According to him, since one can drink the tea with the leaves in, filtering the tea through one's teeth, the tea is considered a liquid which may be drunk without being filtered first, so that it is like clear water and there is no prohibition to filer it.  The Ketzot Ha-shulchan (Ch. 125, Baddei Ha-shulchan, 21) writes something similar, and so does Rav Ovadya Yosef (Yechaveh Da'at, Vol. II, Ch. 51): since most people will not be perturbed by some leaves landing in their teacup, as they always have the option of filtering through their teeth, the liquid is considered clear, and it is permissible to strain it even with a strainer.

In conclusion, it is permissible to use a teapot with a built-in strainer; however, one should be careful not to use it when there is a small quantity of tea left.  Nevertheless, one who is lenient in this has valid opinions on which to rely, and this seems to have been the practice of the Chazon Ish and other halakhic luminaries. 

Teabags

Nowadays, most people use teabags.  At first glance, this should be forbidden, because there are grains in the bag, which functions as a filter to keep the grains in while letting the liquid pass.  To understand the common custom to permit teabags on Shabbat, we must consider another ruling of the Shulchan Arukh (319:9):

Even if a strainer has been hanging from Erev Shabbat, one may not put lees in it; but if one put lees in it on Erev Shabbat, it is permissible to pour water on them so that the clear [liquid] will flow again.

The Shulchan Arukh allows pouring clear water over the lees in a strainer.  The water will absorb a bit of the wine which is absorbed in the lees, even through the water is commingled with the lees, and after that it is filtered by the strainer.  The Mishna Berura explains:

The reason that there is no issue of borer with pouring water is that the water is clear, and there is nothing in it which needs to be selected.

In other words, the prohibition of borer applies only to things which were originally commingled; if the water starts out clear, becomes mixed with lees and then is filtered out through a strainer, there is no issue of borer.

According to this, there is no problem using a teabag on Shabbat, since at the start, the water is clear, and only afterward is it mixed with the grains of tea in the bag, from which it emerges as filtered tea.  This explanation appears in the Minchat Yitzchak (Vol. IV, 99:2). 

Removing the Teabag from the Cup

One concern in using a teabag is that when one removes the teabag from the cup, some drops fall from the bag into the cup.  This is a problem of borer (the bereira of the drops via the bag, which is considered a strainer).  In Shemirat Shabbat Ke-hilkhatah (Ch. 3, n. 171), Rav Neuwirth cites Rav S.Z. Auerbach's view:

It is appropriate to be stringent not to remove the teabag and hold it in one's hand so that the water will flow out, for even though the water was originally clear...  holding the bag so that the water will flow out of it is more serious, since the water and the leaves are already commingled.  Removing the bag and holding it in one's hand is like filtering cloudy water, not clear water...  However, if one only removes the bag from the water and has no interest in the liquid coming out, it may be that even if it is inevitable that some drops will drip from the bag, nevertheless, since they come out easily — even if one only lifts and holds it, the filtering is effected on its own — it may be that it is not considered borer.

According to him, one should be stringent and not leave the bag above the cup so that the tea will drip in.  In this case, we do not say that the water starts out and ends up clear because the removal of the bag from the water is considered a new act.  Therefore we ignore the original state of the water in the bag and focus on its current state — commingled with the tea grains in the bag — so that it is considered like cloudy water which is being filtered by the teabag as it drips into the cup.  The Minchat Yitzchak rules similarly (ibid).

However, Rav Auerbach adds that if the person does not intend to select, but the drops come out on their own while the teabag is being removed, there is no prohibition of borer in this.  Therefore, one must not hold the teabag above the cup so that it will drip into the cup; rather one must transfer the teabag elsewhere immediately.  It is preferable to remove the teabag with a spoon, so that one can avoid the prohibition of borer altogether (Shemirat Shabbat Ke-hilkhata 3:58).

In conclusion, it is permitted^[6] to use a teabag on Shabbat.  It is permissible to remove the teabag from the cup as well, but one should transfer it quickly away from the cup and not allow it to drip back into the cup.

A Slotted Spoon

At first glance, one should forbid the use of a slotted spoon on Shabbat, because this is filtering by way of a keli.  Should we compare this keli to a sieve and a sifter, which are forbidden by Torah law, or to a reed-basket and a tray, which are banned rabbinically? 

On the one hand, this is a keli designed for straining, and if so, it should be no better than a sieve.  On the other hand, it is used for taking okhel out, and it may be that the straining is merely a convenient side-effect. In other words, this keli is used for straining as well, but it may be that it has more significant purposes.  The Or Le-Tziyon (Vol. II, 31:10) writes that this keli has the status of a reed-basket, and its use is prohibited only on the rabbinic level.  This view is compelling, especially in light of the fact that it may be that such a spoon is like a "long hand", since it is used to present food, and if so it is not like bereira with a keli at all.

That being said, it is still forbidden to use a slotted spoon, at least rabbinically.  However, the Or Le-Tziyon (ibid.) writes that there is room for leniency in this matter:

Question: Is it permissible to take out okhel from the soup pot with a ladle which has holes in it by which the liquid is filtered out, or is there a prohibition of borer?

Answer: One should allow removing okhel with this ladle even though the soup is filtered out by way of the holes, if one's intent is to eat it immediately.  In any case, one who is stringent in this matter is praiseworthy.

In a note there, he explains:

Even though apparently, on a rabbinic level, there is reason to forbid it when one does so with a keli, because it is like a reed-basket or a tray... nevertheless, one may enlist the view of those who rule that bereira is inapplicable to liquids.  Even according to those who believe that bereira is applicable to liquids, there is no Torah prohibition, because it is like a reed-basked and a tray, which are rabbinically banned, since they are not utensils designed for bereira, and the same applies to a ladle, which is not specifically designed for bereira.  Therefore one may permit this. 

According to him, one may use a slotted spoon in order to remove a solid from a liquid, since one may enlist the view of those who hold that bereira is inapplicable to liquids, so that the solid inside a liquid is not considered to be commingled with it (Ba'er Heitev 319:2, in the name of the Maharitatz). 

The Shevitat Ha-Shabbat (Merakked, Be'er Rechovot, 26) allows using a slotted spoon in order to separate vegetables from soup and the like, in light of the view we mentioned above, that since many people eat the broth and the vegetables together, the mixture is considered to be a clear liquid, which may be filtered. 

However, we have seen that Rav Auerbach disputes this view of the Shevitat Ha-Shabbat.  Moreover, it is difficult to rely solely on the view that bereira is inapplicable to liquids; therefore it is appropriate to be stringent and to refrain from using a slotted spoon on Shabbat.

Practically, using a slotted spoon also raises another problem: even if we say that the spoon is not defined as a keli, or in any case it is not a keli which is forbidden by the Torah, one must wonder whether removing with it vegetables from soup and the like is considered to be selecting okhel from pesolet.  On the one hand, if one is interested in vegetables, at the time one puts the spoon into the soup and then raises it, one is removing okhel from pesolet.  On the other hand, if one waits for the soup to drip through the holes in the spoon, this means that right now one is separating pesolet from okhel.^[7]

Putting a Spoon against the Wall of the Pot

A similar problem may arise when one puts a regular spoon next to the side of the bowl or the pot, e.g., to remove vegetables or noodles without broth.  In Shemirat Shabbat Ke-hilkhatah (Ch. 3, n. 159, according to Tikkunim U-milllu'im ibid.), Rav Neuwirth writes:

I heard from Rav S.Z. Auerbach...  that he had a question: perhaps one should be careful and not put the noodles in the spoon next to the walls of the bowl in order to let the broth in the spoon flow out, since the spoon together with the bowl is considered a keli.  One should not do this even if one's intent is to eat both of them.

Even if we do not say that this is considered bereira with a keli, one may still forbid it because it is bereira of pesolet from okhel.  However, if in the top part of the spoon there is clear liquid, one may pour it into the pot, since this broth is not commingled with the vegetables or with the noodles.^[8]

Therefore, one who wants to remove certain vegetables from the soup, particularly when one wants to remove them without liquid, should use a regular spoon or a fork; furthermore, one should take first the okhel from the pesolet.  Similarly, one may put a regular spoon or ladle into the top part of the liquid and remove the broth alone (because this is selecting okhel from pesolet, and here one is not using the wall of the keli). 

In conclusion, it is preferable not to use a slotted spoon, because this may involve a prohibition of borer (even though one who uses it has support; in any case, one should not suspend it over the pot so that it will drip).  Similarly, it is appropriate not to place the ladle (even if it has no perforations) against the walls of the pot in order to remove the liquids, since this is removing pesolet from okhel (and perhaps even bereira with a keli).  Sometimes, it is convenient to remove vegetable specifically with a regular spoon or fork, because in this way one is able to remove particular vegetables without liquid.  Similarly, one may put a ladle into the top part of the liquid so that only broth will enter.

A Saltshaker with Rice

Some people put grains of rice into the saltshaker in order to absorb the moisture in the salt.  Is it permissible to use such a saltshaker on Shabbat?

In this case it would seem that there should be a prohibition of borer, as the shaker is like a strainer, since the salt comes out and the rice stays in — which is berera by way of a keli.  While the main objective of the saltshaker is to sprinkle the salt rather than filter it; nevertheless, we have already seen that there is a rabbinic ban on using a keli which assists in bereira, even if it is not designed for bereira.  Rav Moshe Feinstein is quoted (in Rav Shimon Eider's Halachos of Shabbos, Merakked, n. 103) as saying that one should not use such a saltshaker on Shabbat, and this is cited in Shemirat Shabbat Ke-hilkhata in the name of Rav S.Z. Auerbach:

One may put grains of rice (before Shabbat, to avoid a prohibition of muktze) in an open saltshaker in order to absorb the moisture in the salt; in a well-covered saltshaker, one should not take salt out through its cover, even if there is a lot of salt left mixed in with the rice. 

However, there are many reasons to be lenient and allow one to use such a saltshaker:

1.    Generally, a saltshaker contains a lot of salt and a tiny bit of rice, and one does not need the perforations in the cover to take out only salt, so that the keli is not assisting in bereira.  Even when there is just a bit of salt in the saltshaker, one may be lenient and say that since one could readily open the saltshaker and remove just the salt, the keli does not assist in bereira in a significant way.

2.    One may rely on the view of Rav Auerbach that a keli which is always used for bereira for immediate consumption is not considered a keli.  In Shemirat Shabbat Ke-hilkhata (Ch. 3, n. 125; Tikkunim U-milllu'im, ibid.), Rav Neuwirth writes — contradicting what we noted above —

I heard in the name of Rav S.Z. Auerbach that it is possible that a keli which is designed for selection for immediate use is not included in the prohibition to select with a keli...  According to this, one should permit [using] a saltshaker with rice.

3.    The person has no intent of bereira.  Even though the separation is an inevitable result, there are those who are lenient when it comes to an inevitable, unintentional result (pesik reisha).  Even those who are generally stringent may concede here, as there are other reasons to be lenient.

4.    This is derekh akhila (the way of eating) and not derekh bereira (the way of selection).  (See Tefilla Le-Moshe, Ch. 38.) 

The Az Nidberu (Vol. IV, Ch. 23) raises many of these points:

Therefore, my view is to allow [the use of] a saltshaker.  It is not like a reed-basket, which is rabbinically banned, because one's aim [with a reed-basket] is to perform bereira; but when one has no such intent, and it is not an act of bereira, we have not found that the Rabbis should forbid this...  One may add that since this is customarily done during the actual time of akhila, and this is its derekh akhila, it is as if it is impossible to do otherwise...  It appears that there is another reason that borer is not applicable here: this is not classified as a mixture, since the rice mixed in is there in order to maintain the salt; therefore, it is not called borer of one type from another type or okhel from pesolet. 

Other halakhic authorities agree as well (Rav Elyashiv and Rav Karelitz, as cited by the Ayil Meshullash, Ch. 7, n. 110; Tefilla Le-Moshe, Ch. 38; et al.) that one is allowed to use a saltshaker with rice on Shabbat, and this is the practical halakha. 

Lettuce Dryer

May one use a device that uses centrifugal force to dehydrate lettuce (in which one turns a crank, spinning the lettuce leaves so that the water flies off them)?  Apparently, such a device should not be allowed on Shabbat, because it seems akin to a strainer; beyond this, there is bereira of pesolet from okhel (casting the undesired water droplets off of the lettuce leaves).

However, practically, there is reason to allow this.  As we have seen, one may even use a strainer to filter clear liquids.  The reason is that most people drink the water without filtering, and thus the filtering is not a true tikkun of the water; alternatively, the water and debris are considered to be of the same type.  Similarly, there is no problem to eat the lettuce when it is wet.  People dehydrate the lettuce in order to allow it to last a long time without becoming moldy, or they find the lettuce tastier in this way; nevertheless, most people would be willing to eat the lettuce without dehydrating it.  Therefore, drying lettuce is not a significant tikkun.  Moreover, the water is insignificant in relation to the lettuce, so that they are considered to be of the same type; therefore, drying the lettuce does not constitute a violation of borer.[9]  The Mishna Berura (320:24) rules similarly in a comparable case, talking about someone who wants to squeeze cooked or pickled vegetables in order to eat them without liquid:

One may squeeze out the liquid which floats on top of them or is absorbed in them in order to prepare them to be eaten alone, as one does not need their liquid, just as it is customary to squeeze lettuce after it has been soaked in water.  One is not in violation of mefarek [a subcategory of threshing], even if one squeezes the liquid into a bowl and does not let it immediately go to waste; in any case, since one is not interested in the liquid, it is not included in the melakha.

The Mishna Berura writes that one may squeeze the water out of the lettuce without violating mefarek, since one does not want the water.  However, why is there no prohibition of borer?  One is taking out pesolet from okhel!  It appears that because the water does not bother one who wants to eat the lettuce, even if it is wet, there is no problem of borer.  According to this, one may permit dehydrating the lettuce even with a device designed for this purpose, just as it is permissible to strain clear liquids with the use of a mishmeret.  Thus straining of this type is permitted, a ruling which has been confirmed by Rav Asher Weiss.