We recommend Parish Crossroads (located in Kokomo, Indiana) as a source for low-gluten hosts; visit www.ParishCrossroads.com or email [email protected] for information.The most recent Church teaching on the use of mustum and low-gluten hosts at Mass remains the letter from then-Cardinal Joseph Ratzinger. . . on July 24, 2003 (Prot. n. 89/78-17498), which was addressed to the Presidents of Conferences of Bishops. In that letter, pastors and the faithful are reminded that for bread to be valid matter for the Eucharist, it must be made solely of wheat, contain enough gluten to effect the confection of bread, be free of foreign materials, and unaffected by any preparation or baking methods which would alter its nature. The amount of gluten necessary for validity in such bread is not determined by minimum percentage or weight, though hosts which have no gluten are considered invalid matter for Mass. (In the Roman Rite, the bread prepared for the Eucharist must also be unleavened.)
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The lay faithful who are not able to receive Holy Communion at all under the species of bread, even of low-gluten hosts, may receive Holy Communion under the species of wine only, regardless of whether the Precious Blood is offered to the rest of the faithful present at a given celebration of Mass.