Q. One who has only chodosh bread on the first night of Sukkos. Is he allowed to eat it or no? If yes, how much should he eat? What about having only chodosh bread for the Shabbos seudos?
A. Chodosh, literally "new", are products made from new grain, that was planted close to, during, or after Pesach, thereby taking root after the time of the omer sacrifice, and are not permitted to be eaten until the following Pesach. Some have the tradition to abstain from them. Mishna Berura (O. H. 489: 45), writes that most do not abstain from chodosh in our days, since they consider that it only applies in Eretz Yisroel. However, he adds that a baal nefesh and conscientious consumer should strive to adhere to the laws of chodosh. Many see it in by today's standards, as kosher vs. glatt kosher.
Horav Shlomo Miller's Shlit'a opinion is that if one is particular not to eat chodosh, and cannot find yoshon, he should abstain from eating bread. He may however, eat a proper shiur from mezonos that are Yoshon. The same would apply to the Shabbos seudos.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit'a