Technology and Scientific Developments Impact on Halocha / Lettuce, Chicken, Ovens, Refrigeration, Lab Grown Meat

Rav Yaakov Yisroel Kanievsky zt”l (The Steipler) in his Sefer, Chayai Olam, quotes the Zohar that the wellsprings of scientific knowledge will gush forth during the latter part of the sixth millennia.   We all see that this scientific progress may be harnessed in the service of HKB”H, or it may be used for nefarious purposes.  We will discuss how some of the technological and scientific developments impact practical halocha.


Many people ask, “Why is it that standards for cleaning fruits and vegetables have changed.”  We will supply a few answers for this legitimate question.

Due to developments in transportation produce is shipped worldwide.   Many pests have “hitched” rides on ships and planes thereby spreading from one part of the world to another.  A few examples are the Norway rat, the Japanese beetle, and the Mediterranean fruit fly.  These pests become even more challenging when they become established in areas where their natural predators are not found.  In addition, food scientists constantly breed plants and animals to enhance sought after characteristics, or to minimize unwanted attributes.   One example of this is Romaine lettuce.  Romaine lettuce is naturally bitter.  In fact, the Mishna classifies Romaine lettuce as a form or Marror.    Through selective breeding the natural substances that make Romain lettuce bitter have been minimized.  While we still use Romain lettuce as Marror, we can now understand why we can only detect minimal bitterness.  This may also make the lettuce more palatable to the pests that cause us halocha concerns.


Selective breeding has had a major impact on the chickens we eat.  Recently the Kashrus agencies became alarmed.  The Gemora states that kosher birds normally perch with one toe in back.   Our chickens (mostly white Leghorns) were found to perch with two toes in back.   After researching the topic, it was found that selective breeding, intended to produce more white meat and to make the chickens grow faster, caused the chickens’ toes to break.  Because of the damage to their feet the chickens had to use two toes in back to perch securely.   A Canadian university still has descendants of lines of chickens that have not undergone selective breeding since the mid-1900s.  Even with an identical diet these lines of chickens are only 1/3 of the weight of current chickens (that have undergone selective breeding) which are the same age!   (We will not address the issue of Tzar Baalei Chaim, Cruely to Animals, and possible health issues of tampering with Nature in this article.)

Ovens / Refrigerators

The “bells and whistles” which are built into modern electronic appliances – ovens, refrigerators, and freezers, have introduced many halocha questions that did not exist one or two decades ago.  The kashrus agencies have worked with the manufactures to create what is called a “Sabbath Mode”.  Many of the “Sabbath Mode” functions really apply to Yom Tov.   The application of “Sabbath Mode” varies from brand to brand and model to model.   On some models (that are not certified by a recognized Rabbinic organization) the Sabbath mode is not done correctly which can impact negatively on halocha and function.  It is prudent to check with an expert before making such a major purchase.  If you have already purchased your appliances and have questions about the “Sabbath Mode” you should research it through Rabbanim that have the requisite technical information.  The Star-K of Baltimore has a technical consultant who is familiar with most major brands.  The Star-K’s secretarial staff is extremely knowledgeable and very helpful.  If you cannot get the required information through the Star-K’s website, you should call the Star-K’s office.  While the Star-K generously shares technical information they follow the halocha decisions of Rav Moshe Heinemann shlit”a.  When it comes to practical halochic application you should consult with your own rabbi.

Several links are provided for your convenience.  It is important to keep in mind that while properly selected “Internet” articles are helpful in researching a topic, they are no substitute for the guidance of your own rabbi.


Lab Grown Meat

Biologists are making major advances in the ability to grow meat from stem-cells.  Rabbi Gennack of the OU and his team of researchers have been investigating the halochic implications of these developments.   The current position of the OU is that the stem-cells must be derived from a kosher slaughtered animal.  At this time the position of the OU is that the meat which is produced in this manner should be considered “fleishig” – at least Rabbinically.  As this is a very new issue in the field of Kashrus, research is ongoing.

It is truly amazing how all areas of knowledge and wisdom impact and serve the Torah Jew.