Coming Soon from OU Press – Fall 2025
HaHashgachah KeHilchatah: Shorshei HaKashrut HaTzibburit (Kosher Certification According to Halachah: The Foundations of Communal Kashrut)
By Rabbi Peretz Moncharsh
OU Press
OU Kosher prides itself on transparency and accountability to the kosher consumer. Now, the world’s premier kosher certification has taken the next step, opening up its halachic decision-making process to the world’s Torah scholars.
From the beginning of his tenure, OU Kosher CEO Rabbi Menachem Genack has made it a point to establish OU policies in consultation with top-tier posekim. At first, Rabbi Genack consulted with his teacher and mentor Rabbi Joseph B. Soloveitchik, zt”l; after the latter’s passing, Rabbi Genack recruited Rabbi Yisroel Belsky, zt”l, and (yibadel lechaim) Rabbi Hershel Schachter as official halachic consultants to weigh in on the pressing kashrut questions of the day.
As the OU expanded its reach to over 100 countries, 13,000 plants and 1.3 million certified products, halachic questions arose in unprecedented volume and complexity. Classic halachic texts offered little explicit guidance on the rapidly evolving technologies of modern food production and the sophisticated equipment it relies on. Only halachic authorities of such a caliber—deeply versed in both traditional sources and contemporary industrial realities—could extrapolate from existing literature to address questions such as whether microbial enzymes grown on media containing a non-kosher ingredient are permissible, or how to properly kasher a spray dryer.
While the OU has long maintained an internal archive of halachic rulings—meticulously compiled by Rabbi Moshe Zywica, executive rabbinic coordinator and director of operations at OU Kosher—these decisions were largely inaccessible to those unfamiliar with the sugya (topic) and typically circulated only among OU kosher staff. Recognizing the value of these documents for scholars and laypeople interested in contemporary kashrut, Rabbi Yaakov Luban, former senior rabbinic coordinator, took the initiative to transform OU Kosher policy into a user-friendly book.
To that end, Rabbi Luban enlisted Rabbi Peretz Moncharsh—rosh kollel of Kollel Shaarei Horaah in Beitar, Israel, and widely respected for his halachic clarity—to transform OU Kosher’s internal halachic documents into a resource accessible to the broader public. Rabbi Moncharsh was granted full access to the OU Kosher archives as well as to current OU Kosher staff, particularly Rabbi Eli Gersten—recorder of OU pesak and policy—enabling him to present the most comprehensive picture possible of the intersection between classical halachic literature and contemporary OU Kosher practice.
Each chapter opens with a comprehensive discussion of the topic, beginning with the Gemara, progressing through the views of the major Rishonim and Acharonim, and continuing to contemporary halachic authorities. The chapter concludes with OU Kosher’s final policy decision, as determined by its senior halachic staff. To ensure accuracy, the author consulted extensively with Rabbi Belsky during his lifetime to fully understand his positions. The entire work was also reviewed by Rabbi Schachter, who confirmed that his own views were represented faithfully. Included as well is Rabbi Genack’s monograph on the topic of bishul akum in regard to industrially produced food today.
Many sefarim offer extensive and penetrating analysis of the laws of kashrut. What sets this work apart is its unique lens: the contemporary challenges of industrial kosher supervision. While other volumes may focus on the halachot of pots and pans, this one delves into steam-jacketed kettles, enzymes, cheese production, dairy English muffins, kosherizing industrial machinery, large-scale insect inspection and more.
As the largest kosher certifier in the world and a pioneer in applying the laws of Yoreh Deah to modern commercial food production, OU Kosher is uniquely positioned to spearhead this important contribution to halachic scholarship. This book will appeal both to those deeply engaged in the study of Yoreh Deah and to the simply curious—those who’ve wondered about the halachic reasoning behind the certification of their favorite snacks. Given that kashrut has long been a cornerstone of rabbinic training, this volume also serves as an invaluable resource for rabbis and rabbinical students seeking to broaden their knowledge from kitchen-based halachah to the complexities of industrial kosher supervision.
While some kosher agencies formulate their policies behind closed doors, the OU has long maintained a different approach, with full-time staff dedicated to answering consumer questions. Now, the OU has taken a step further—proactively sharing its halachic expertise in a way that enriches the broader halachic literature. Anyone curious about the depth of thought and effort behind the OU symbol will find this book both illuminating and rewarding.