There are a number of Halachic issues that are brought into play in determining the kashrut status of manufactured products in today’s environment. However while the technological processes may be new, the Halachic principles - in general terms - are old and well known.

The Nodah B’Yehudah1 was asked about the kashrut status of a certain alcoholic drink that used non-kosher animal meat as part of the production process. In his responsa the Noda B’Yehuda ruled that as the non-kosher ingredient was totally insignificant in the final product and did not add to the taste of the same - the ingredient was considered nullified (botul) and the final product kosher. As to the prohibition of purposefully nullifying a prohibited product - The Noda B’Yehuda ruled that as the drink was manufactured by non-Jews for non-Jews2 - there could not be placed on a non-Jew any prohibition and one only had to look at the final product. If however the product was being manufactured by Jews then the product would be considered not kosher. The Nodah B’Yehuda rules that anything that is permissible post facto (B’diavad) in a Jewish home is permissible before the fact (L’Chatchila) if produced by a non-Jew for non-Jews.

Many centuries earlier the Rashba3 dealt with a similar problem. It involved a particular food that used miniscule amounts of non-kosher vinegar in the course of production. The Rashba ruled that the product remained forbidden. He argued that the laws of nullification apply only when an ingredient falls into a product accidentally. If however it was put in on purpose then regardless of the amount and regardless of whether done by Jew or non-Jew the product remains not kosher. According to the Rashba the Nodah B’Yehudah’s alcohol would be not kosher. 

Indeed the Nodah B’Yehudah acknowledges the Rashba - but dismisses him. He argues that the Halacha is not like the Rashba but rather like Maimonides who the Nodah B’Yehuda posits disagrees with the Rashba. 

This difference of opinion becomes critical in the determination of the kashrut status of manufactured products. For example: An orange flavour used in the sweetening of an orange drink may have as many as ten or fifteen components , some of which may be not kosher. If it is a component that actually alters noticeably the taste of the final product then all would agree that the final product is not kosher - but invariably this is not the case. The single component by itself would have an insignificant effect. According to the Noda B’Yehuda the drink would be kosher. However, according to the Rashba, as it is a purposeful ingredient, it would not be nullified and the final product would be not kosher.

The majority Halachic view today is to follow the ruling of the Noda B’Yehuda.4 However there are Poskim of significant note that rule like the Rashba. One of them is the Shulchan Aruch HaRav.5 His grandson the Tzemach Tzedek however rules like his grandfather when it comes to the laws of Pesach6- but appears to take a more lenient approach when it comes to regular kashrut not for Pesach - indeed quoting the Nodah B’Yehuda. 7

The Ksav Sofer 8 takes what appears to be a compromise approach. His view is that one may rely on this leniency only when there is no equivalent product available at the same price - but if there is an equivalent product available then one should be machmir and purchase a product that has not relied on this leniency.

All the above of course applies when the factory is manufacturing for non Jews. What if the factory is producing for non-Jews and increases its production for the Jewish market - in such a case even the Noda B’Yehuda would forbid the final product. What if the company has no plans to increase production for the Jewish market but never-the-less wants a kosher certificate for the final product to satisfy potential kosher consumers. Even in such a case poskim agree that the product is kosher. However Rabbi Moshe Feinstein Zatza”l is oft quoted as making the following qualification: “Mechuor hadovor” - it is grossly inappropriate to give a Hechsher and receive fees when one is relying in advance on nullification.9 

In conclusion, the following principles in relation to nullification of a forbidden substance and other leniencies that may be employed in a non-Jewish factory arise from the above discussion.

1. If a kashrut agency is certifying a product and the company is producing especially for the kosher market - no leniency may be employed.
2. If a kashrut agency is certifying a product already being produced not especially for the kosher market, and is charging for that certification - then it is grossly inappropriate to rely on nullification or similar leniencies.
3. If a company is producing a product for the general non-Jewish market, and the company does not request certification nor does it pay for it - but rather allows the kashrut agency to investigate the product and list it as kosher - then Halachically one may rely on nullification and other leniencies that would normally be allowed only post facto in the home of a Jew. Those who wish to be stricter and follow the ruling of the Ksav Sofer would rely on this only if an equivalent product at an equivalent price was not available. 

Application Of The Above In The Kashrut World Today

The United States and Israel 

As the kosher consuming market in those countries is very large the normal mode of identification of kosher products is through certification. It can universally be assumed that when a company desires a kosher status it is to significantly attract the kosher market and ultimately increase production. Hence almost all kosher work is done via certification and nullification can not be relied upon.

The Rest of the World

In the rest of the world two parallel systems apply. On the one hand there are companies who seek certification - and they do so to increase their market potential and often to export to the larger markets of the US and Israel. In the certification of these products nullification can not be relied upon. However there are also companies that consider the kosher market as totally insignificant - and they give permission to have their products checked. They expect no significant increase in turnover whatsoever. In such cases nullification may be employed, or at least a less thorough sub ingredient check, as well as some other leniencies mentioned in the poskim. 

These products are often published in lists with the notification that indeed these are not certified products but endorsed products. Such lists appear in Australia , South Africa and the United Kingdom as well as other countries.10 According to the Noda B’Yehuda such products, considering the particular circumstances, are as kosher for the final consumer as formally certified products. The Ksav Sofer would concur only when there was no similar product at the same price available.

The Kashrut Authority

Standards of Kashrut are continually improving in Australia as well as the rest of the world. In the sixties and seventies, Rabbonim would more frequently rely on the Noda B’Yehudah’s principle and employ such leniencies. As the availability of kosher certified products increased with the ever growing kosher market, kashrut agencies began to rely on such leniencies less and less - usually as an acknowledgement of the size of the kosher market and the increased availability of mehadrin products which gave greater scope for the stricter view of the Ksav Sofer and even the Rashba.11 

The Kashrut Authority policy today is as follows

1. If a product is certified as kosher then no leniency is relied upon whatsoever. Products that bear the Diamond KA logo on the label are always certified.
2. If a product is not being certified but is being endorsed for inclusion in the kosher list then
    a) If there is definitely a non kosher ingredient then the product will not be listed regardless of the ability to nullify. 
    b) If there is a doubt as to the nature of an ingredient or if sub-components have not been able to be thoroughly investigated - then the nodah b’yehuda will be relied            upon to alleviate the doubt. It is arguable that even the Ksav Sofer would agree in such circumstances.
    c) Certain leniencies may be employed in relation to kosherisation of equipment and supervision of such kosherisation as well as frequency of visitation again relying on      the Noda B’Yehudah and other poskim.
3. It has become common practice, to declare products that are certified or that have undergone a thorough investigation equivalent to the certification process even though they are not formally certified as Mehadrin. Those products however that rely on the Nodah B’Yehuda and the like are declared not-Mehadrin. The appropriateness of such differentiating language is indeed questionable as the Noda B’Yehuda would indeed consider his ruling to be of a Mehadrin standard - and would not require the consumer to be any stricter whatsoever. Usage of such language implies that the more scrupulous individual would not rely on such a leniency. Is not the kashrut standard of the Noda B’Yehuda mehadrin? Never the less custom and usage play a role in Halacha and as such the terms remain (perhaps out of deference to the view of the Rashba mentioned earlier).
4. In the list of endorsed products The Kashrut Authority has chosen to specifically differentiate between Mehadrin and not Mehadrin in relation to oils and other products that are equally available and equally priced with the non-Mehadrin products - in line with the similar advice of the Ksav Sofer. Our caterers and establishments will follow the same principle. Also when non-mehadrin oils are a minor ingredient other mitigating Halachic factors come into play that allow for even the meticulous to be more lenient and it is our opinion that this is in the spirit of the Ksav Sofer and still Mehadrin. When in the opinion of the Kashrut Authority a particular product is not mehadrin we will generally comment on that in the guide.

Kashrut is one of the most important facets of Jewish living. Reputable Kashrut agencies will continue to provide an ever growing mix of kosher products while maintaining Halachic standards of excellence.

Note that the above discussion involves complicated Halachic issues and the lay person should not make Halachic decisions based on any of the information contained therein.


1.Nodah B’Yehudah YD - MH”T Siman 56. See also Darcei Teshuva Y”D Siman 108 S”K 20 for a full listing of poskim. The Noda B’Yehuda has been chosen specifically by the author as the primary reference as he deals with the Rashba.
2. When the non-Jew manufactures for Jews even on his own initiative it is as if the Jew has asked the non-Jew to cook for him and this leniency can not be used See Rav Foifer’s Kitzur Shulchan Aruch Hilchois Ta’aruvois P.97 for a thorough listing of the Poskim who deal with this and his view as to accepted practice. 
3.Teshuvois HoRashba Vol 3 Siman 214 brought in Beis Yosef at the end of YD Siman 144. 
4.See the Darchei Teshuva mentioned above in #1 and also Rav Foifer’s Kitzur mentioned in #2.
5.Shulcha Aruch HoRav O”C Siman 442 Seif 6 and in the Kuntres Acharon S”K 5. 
6.Tzemach Tzedek O”C Siman 43
7.Tzemach Tzedek Y”D Siman 67 & 68. This is a fascinating series of teshuvot in relation to sugar manufacture that in his times was made with a 2% addition of a blood mixture which was used as a flocculant and clarifying agent. The Tzemach Tzedek is mattir the sugar and even allows Jews to 
manufacture it. He deals there with many of the issues raised herein.
8. Ksav Sofer O”C 87.
9. The actual responsa IG”M Y”D-2 Siman 41 refers to giving hashgacha - supervision- to margarine produced on non-kosher vessels that have not been used for 24 hours and then relying on “nosein taam lifgam muttar”- that after 24 hours of non use a vessel can not impart prohibited taste. The author has not been able to ascertain with certainty that Rabbi Feinstein has said this in relation to bitul-nullification however logic dictates that the mechuor hadovor extends to giving a hashgocho in any situation where one is taking advantage of the post-facto of a non-jew doing something that for a jew in the first instance would be forbidden. This is indeed how kashrut authorities including representatives of the OU have interpreted the responsa to me. Furthermore, to formally supervise a company and receive fees when employing such leniencies certainly invokes the mechuor hadovor. This is in contrast to investigating the ingredients of a product and production processes without formal hashgocho and fee collection where the mechuor hadovor would logically not apply. It should be noted that there may be Kashrut agencies that do not follow this directive of Reb Moshe - however it appears clear from the responsa that this would not affect the ultimate kosher status of the final product as far as the consumer is concerned and they would be permissible.
10. It is interesting to note that the first country to publish a comprehensive list, to the best of the author’s knowledge, was indeed Australia. The work of Rabbi Osher Abramson zatza”l and yiblch”t Rabbi Mordechai Gutnick (at that time) of the Sydney Beth Din as well as Dr Uhrmann za”l of the Mizrachi Kashrut Committee must be singled out for special mention. They were the forerunners of the current comprehensive lists produced by the NSW Kashrut Authority and Melbourne Kashrut .
11. It was reported to the author in the name of Rabbi Henkin Zatza”l that he had said that the view of the Rashba is the raison d’etre of US Kashrut certifying agencies. This may have been in his time. One could argue that nowadays as the kosher market in the US is so large and does indeed affect production levels that even the Noda B’Yehuda would be machmir.
12.This is a chumra in deference to the possibility that the market for kosher is growing and may affect one’s ability to rely on the Noda B’Yehuda - see #2 above and of course in 
deference to the Rashba.