How Do We Make Kosher Wine?

Kashrus is significant to this week’s parsha, and right after Purim and beginning our Pesach preparations. This seems like the perfect week to discuss how we make kosher wine.

Question: Business Lunch

“On a business visit to Israel, I needed to take out some non-Jewish business contacts to a top-quality restaurant, but I was told that I could not order wine to accompany the meal. Yet in America I do this all the time. What am I missing?”


The importance of wine to Jewish celebration cannot be underestimated. The pasuk in Tehillim (104:15) teaches that wine gladdens a man’s heart. Chazal, also, treat wine as a special beverage, and therefore it has its very own beracha. Every special event – kiddush, havdalah, weddings, sheva berachos, brisin, pidyon haben – includes a beracha over a cup of wine. And halachah mentions the special role of wine in celebrating Yom Tov.

Grapes and the contemporary “food chain”

In addition, the importance of grapes in modern use can not be taken lightly. Grape-based products are used extensively in all types of food production, including alcohol, liquor, wine vinegar, flavors, natural extracts, colorings, sweeteners, juice drinks, jam, jelly, preserves, candies, fruit ices and various other foods. Thus, not only the wine connoisseur but also the teetotaler and everyone in between are using grape products, although they often do not realize it.


Many years ago, I was contracted to oversee a special production of kosher grape concentrate, which is another way of saying grape juice with most of the natural water removed, at a non-kosher plant. The entire four-day production was ordered specifically in order to produce a run of kosher fruit ice.

Producing kosher wine

Manufacturing kosher grape juice and wine is a complicated process that requires a very knowledgeable and yarei shamayim staff. From a kashrus perspective, grapes are unusual. They are kosher when they grow, yet kosher wine and grape juice must be manufactured without the product being touched or moved by anyone but an observant Jew. If the product was produced in any other way, it is no longer kosher.

Why is this?

What are yayin nesech and stam yeinam?

In addition to the cardinal prohibition against worshipping idols, avodah zarah, the Torah distanced us from any involvement with or benefit from avodah zarah. One of the laws relating to idol worship is the prohibition from using an item that was used to worship idols, called tikroves avodah zarah. According to the accepted halachic opinion, using tikroves avodah zarah is prohibited min hatorah (Rambam, Hilchos Avodah Zarah 7:2; cf. Tosafos, Bava Kama 72b s.v. De’i, who rules that the prohibition against its use is only miderabanan). Included in the prohibition against using tikroves avodah zarah is that one may not derive any benefit from wine that was used to worship an idol. This prohibited beverage is called yayin nesech, literally, sacramental wine, or wine used for worship.

Chazal extended this proscription by banning use of any wine or grape juice which a gentile touched, and, in some instances, even if he just moved it or caused it to move. This prohibition is called stam yeinam.

Although one may not drink stam yeinam, the halachic authorities dispute whether one may benefit from stam yeinam. According to the lenient opinion, this means that if a gentile who does not worship idols, touched or moved wine that a Jew owned, one may derive benefit from the wine. Notwithstanding this leniency, most authorities prohibit purchasing stam yeinam, and only permit benefiting from it if one already owns it. Nevertheless, a minority opinion permits a Jew to purchase stam yeinam in order to make a profit, and, upon this basis, many Jews own and owned taverns or liquor stores, where they sold non-kosher wine to gentile customers (see Rama, Yoreh Deah 123:1).

Producing kosher wine

Unquestionably, manufacturing kosher wine and grape juice is one of the more complex areas of kosher food production. If one is making kosher wine in an otherwise non-kosher facility, one needs to laboriously kosher the entire factory. The actual manufacture of the wine also usually requires a large team of G-d-fearing individuals, who are all properly trained to fulfill their responsibilities. Furthermore, every facility producing kosher wine should have a resident supervisor who is a talmid chacham and expert in the relevant halachos. It is for this reason that people should be very careful to ask questions before drinking wines, to make sure that the people overseeing the hechsher are knowledgeable and G-d-fearing.

The basics of wine production

Wine is the fermented juice of grapes. All grapes grow with naturally occurring yeast on their skin that, left to its own devices, feeds on the natural grape sugars in the juice, thereby converting it to alcohol. The result is that sweet grape juice becomes intoxicating and delicious wine. This is the way Rashi produced wine in northern France over nine hundred years ago and the way wine was produced until the modern era. Wine produced this way is completely natural, but its taste will vary from year to year, and perhaps even from vat to vat.

Modern wineries rarely produce wine this way, preferring to pasteurize the juice, thereby killing the natural yeast, so that they can control how their wine will taste. After pasteurization, they add specific strains of yeast to produce wine to their desire. The wine is then bottled under vacuum and sealed.

Often, grape juice is concentrated by evaporating off most of its natural water. Grape concentrate lasts much longer than grape juice and has its own uses as a sweetener.

Here come the grapes!

Now let us follow the production – from grapes to bottled wine. Wine grapes are picked and dropped into closed-bottom boxes, since one wants to preserve as much of the juice as possible. The grapes are delivered by truck to the winery, where a forklift picks up the boxes and turns them upside down, dropping the contents into a piece of equipment that removes the stems from the grapes and is therefore called a “destemmer.” What is left is a mixture of grapes and juice that is pumped to a holding tank.

In a properly run hechsher, every step after the initial dumping of the boxes of grapes into the destemmer is performed by an observant Jew. That means that a frum Jew must push the production buttons of the equipment. In the special production that I oversaw, since the mashgichim hired for the special run were inexperienced in plant operations, every production point was manned by two people – a factory worker, who instructed the mashgiach how to operate the machinery, and a mashgiach who pushed the buttons and actually did what needed to be done.

At this point, we need to take a break from the juicing process and turn our attention to a discussion in halachah.

When does it become wine?

As I mentioned before, wine becomes forbidden when it is touched by a non-Jew. At what point is the product called “wine,” causing this prohibition to take effect? While the grapes are growing, or even while they are being harvested, a gentile’s contact will not affect them. So, at what point do we need to be concerned?

The halachic conclusion is that grape product is considered wine once the juice has been removed or separated from the pulp of the grapes (Shulchan Aruch, Yoreh Deah 123:17). This step is called hamshachah, literally, drawing away. When this happens, both the liquid that has been removed as well as the entire remaining mixture are considered wine and become forbidden if handled by a non-Jew. Once hamshachah takes place, if a gentile touches the juice, he makes it prohibited.


I was once visiting a wine production facility with a less-than-stellar reputation for its kashrus standard. While there, I noticed gentile staff remove samples of juice from the crushed material well before the wine had been formally separated. The lab technician dipped a paper cup into the vat to draw his sample, gently separating some juice from the rest. This simple act made the entire batch into prohibited stam yeinam. (If you are curious to know what I did subsequently — I brought the fact to the attention of the mashgiach, who told me that he follows the instructions he is given by the certifying rabbi. I asked the rabbi — who denied that laboratory personnel take any samples, since he had instructed them not to do so. This is merely one example of why this particular brand is avoided by anyone seriously concerned about kashrus.)

As we noted, it is crucial to avoid any contact of non-Jews with the juice from the time any hamshachah has occurred. It is also forbidden to allow a non-Jew to pour wine or move a vessel containing wine, even though he does not touch the wine directly. If he touches a stream of wine being poured from a container, then the contents of the entire container, even that which has not yet been poured, becomes forbidden. For this reason, an observant Jew must operate every procedure during production until the wine becomes mevushal, a concept I will explain shortly. Therefore, a winery must have an adequate staff of qualified mashgichim throughout all phases of the production.

It is permitted to allow a gentile to carry or touch a sealed bottle or container of wine. Also, a non-Jew’s touching the outside of an open container or tank of wine without moving the wine inside does not prohibit the wine.

Back to our grapes

Now that we understand the serious problem that can result from inadequate control, let us return to our juice production. The first step common to all types of wine production is called the “crush” — where the grapes are literally crushed to remove all juice from the pulp. When the crushing is finished, every drop of juice has been removed, and the remaining pulp is so dry that it is almost useless. Sometimes, it can be salvaged as animal feed, other times as fertilizer, or it can be fermented into a product called marc alcohol, but these are not the primary concerns of the wine or juice producer.

The Heat Exchanger

After pressing, the juice is filtered. In most North American wine production, the juice is now pasteurized by processing it in a piece of equipment called a plate heat exchanger. This highly efficient piece of equipment consists of interlocking plates tightly screwed together, in which the product and extremely hot water pass through alternating sections, thereby pasteurizing the juice without losing any to evaporation. The juice is then cooled down and placed in huge, refrigerated storage tanks.

If the wine is to be sold as non-mevushal, the juice is not sent to the heat exchanger, but instead is pumped directly from the filter to the refrigerated storage tanks. This juice will be inoculated with yeast and aged to become the desired wine product.


The Gemara (Avodah Zarah 30a) teaches that the prohibition of stam yeinam does not exist if the wine was mevushal before the gentile handled it. According to the Rambam (Hilchos Maachalos Asuros 11:9), the reason for this heter is because no self-respecting idolater would consecrate cooked wine to his deity. Cooking wine harms it, and cooking grape juice affects its ability to ferment naturally. Indeed, some winemakers never pasteurize the juice from which they produce their wines, because heating compromises the taste. For this reason, halachah views wine that is mevushal as inferior, and this has several ramifications.

The Rosh (Avodah Zarah 2:13) does not consider this a sufficient reason to explain why cooked gentile wine is not included under the prohibition of stam yeinam. He explains that mevushal wine is permitted because it is extremely uncommon, and, therefore, Chazal did not include it within the prohibition of stam yeinam.

Is pasteurization the same is mevushal?

Most American hechsherim treat pasteurized juice and wine as mevushal, and therefore are not concerned if a gentile is in contact with grape juice or wine after it has been pasteurized.

However, many prominent Eretz Yisrael authorities feel that contemporary heat exchange pasteurization does not qualify as bishul. Among these authorities, we find two different reasons. Rav Shelomoh Zalman Auerbach feels that mevushal wine must be a product that is clearly recognized as inferior, whereas pasteurized wine is not considered an inferior product. Even if we assume that certain varieties of wine would never be pasteurized, and we also assume that a professional winemaker can always identify that a wine is mevushal, Rav Shelomoh Zalman contends that mevushal wine must be so affected by the bishul that the typical gentile would notice its inferior quality. However, a modern heat exchanger pasteurizes the product without making a pronounced change in the product’s taste (Shu’t Minchas Shelomoh 1:25).

Those who challenge his approach feel that since pasteurization heats the wine to a sufficient temperature to be considered bishul, the wine meets the standard that Chazal established for it to be outside of their gezeirah. Furthermore, they contend that it is halachically significant that a wine connoisseur will notice whether a wine was pasteurized or not. For example, French wines, Niagara wines, many quality California wines and many quality Israeli wines are not pasteurized, because this ruins the wine’s taste.

Rav Yosef Shalom Elyashiv held a different reason why pasteurized wine does not qualify as mevushal. Since this wine is readily available today, the reason why the Rosh permitted mevushal wine – that it is uncommon — does not apply. The decision of Rav Shelomoh Zalman Auerbach and Rav Yosef Shalom Elyashiv is followed by many contemporary authorities.

Rav Ovadyah Yosef followed an approach in-between the position just quoted and that of the lenient American poskim mentioned above (quoted in Nishmas Avraham, end of Yoreh Deah). Although he accepted that pasteurized wine can be considered mevushal after-the-fact, he considered this psak a be’di’eved, to be relied upon only if a mistake occurred. He forbade a company selling pasteurized kosher wine from labeling the product as mevushal.

Now, we may return to question #1: Someone will have non-Jews at his table and must serve quality wine. What does he do? It is impolite to pour the wine and keep the bottle off the table. Therefore, his only viable option is to serve mevushal wine. May he use pasteurized wine? While the American hechsherim allow him to, according to Rav Shelomoh Zalman Auerbach and Rav Elyashiv he could only bring wine to the table if he first poured it into a pot and cooked it – which will undoubtedly ruin the wine.

It is interesting to note that the earliest discussion of kashrus standards for any food production is mentioned in the context of producing and storing kosher wine in a gentile’s facility. The Mishnah that discusses this topic is the source for the concept of yotzei venichnas, that a mashgiach may exit the facility, as long as the gentiles involved think that he may return at any moment. However, if they know when the Jew will be returning, one has jeopardized all kashrus arrangements. For this reason, every hechsher must be careful that their mashgichim make surprise visits to the factories under their supervision, including visits to the facility in the middle of the night and at other odd times.


The Gemara teaches that the rabbinic laws are dearer to Hashem than the Torah laws. In this context, we can explain the vast halachic literature devoted to understanding the prohibition of stam yeinam, created by Chazal to protect the Jewish people from major sins. We should always hope and pray that the foods are prepared in accordance with all the halachos that the Torah commands us.