  Citation: Co¸ tovanu, I.; Mironeasa, S. Influence of Buckwheat Seed Fractions on Dough and Baking Performance of Wheat Bread. Agronomy 2022, 12, 137. https://doi.org/10.3390/ agronomy12010137 Academic Editor: Ersilia Alexa Received: 30 November 2021 Accepted: 4 January 2022 Published: 6 January 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). agronomy Article Influence of Buckwheat Seed Fractions on Dough and Baking Performance of Wheat Bread Ionica Co¸ tovanu and Silvia Mironeasa * Faculty of Food Engineering, S , tefan cel Mare University of Suceava, 13 Universitatii Street, 720229 Suceava, Romania; ionica.cotovanu@usm.ro * Correspondence: silviam@fia.usv.ro; Tel.: +40-741-985-648 Abstract: The study was conducted to determine the influence of buckwheat fractions (BF) on the physicochemical characteristics of wheat flour (WF), dough rheology, and bread quality parameters. Buckwheat seeds’ fractionation influenced the microstructure and molecular conformation depending on the particle size (PS). The protein content of the WF–BF improved when the medium PS was added and decreased for large and small PS. Lipids and ash increased with the increase in BF amount in all samples in comparison with the control. Dough tenacity increased with BF addition, being higher than in WF dough only when large PS were added, while samples with medium and small PS presented a lower tenacity in comparison with the control. Dough extensibility decreased significantly in all samples when BF increased, as follows: M > S > L. Dough viscoelastic moduli increased proportionally when adding large PS, while the addition of medium PS (5–15%) and small PS decreased it. Bread firmness, springiness, and gumminess rose proportionally with the addition level. Bread volume decreased when BF increased, and medium PS had a good influence on this parameter. Bread porosity and elasticity presented higher values than for the control bread, but these decreased when the BF amount increased. Flour and bread crust and crumb color parameters were also influenced by different fractions of BF addition. Keywords: buckwheat seeds; dough rheology; bread quality; particle size; wheat bread; addition level 1. Introduction The development of a nutrition culture increases the consumption of healthy foods, which leads to continuous research to discover new innovative ingredients that can confer functional properties. It is well known that bread is one of the most consumed foods, but the refined wheat flour from which it is usually made is very poor in nutrients. That is why many studies focus on the nutritional improvement of this product by incorporating various raw materials, with a positive impact on consumer health. One of these is a pseudocereal, buckwheat, that has recently attracted attention as a novel material in functional food formulations because of its outstanding health properties [1,2]. Buckwheat (Fagopyrum es- culentum Moench), a dicotyledonous crop of the Polygonaceae family, is widely distributed in China, Russia, South Korea, Japan, Europe, and other regions [3,4] due to its superior chemical composition compared to that of wheat varieties [5–7]. Buckwheat is one of the potential food ingredients for the functional food industry. A growing trend for consumer demand highlights the need for the development of composite flour-based bakery products such as bread. Buckwheat flour is recognized as a good source of nutritionally valuable protein, lipid, nonfibrous carbohydrates, dietary fiber, vitamins, and minerals, as compared with other cereals such as rice and wheat [8]. The protein of buckwheat flour consists of 2S albumin and 8S and 13S globulin but is very poor in prolamin, glutelin, and has very little or no gluten [9]. Buckwheat is a source of high-quality protein because it contains many essential amino acids such as lysine, histidine, valine, and leucine [10–12]. The kinetics of protein cross-linking depends on their structure and the availability of lysine and glutamine Agronomy 2022, 12, 137. https://doi.org/10.3390/agronomy12010137 https://www.mdpi.com/journal/agronomy