ORIGINAL ARTICLE Shelf-life, physicochemical, and nutritional properties of wheat bread with optimized amount of dried chickpea sourdough and yeast by response surface methodology Muge Hendek Ertop 1 | Yunus Coşkun 2 1 Faculty of Engineering and Architecture, Department of Food Engineering, Kastamonu University, Kastamonu, Turkey 2 Faculty of Engineering and Natural Sciences, Department of Food Engineering, G€ um€ uşhane University, G€ um€ uşhane, Turkey Correspondence Muge Hendek Ertop, Faculty of Engineering and Architecture, Department of Food Engineering, Kastamonu University, Kastamonu, Turkey. Email: mugeertop@kastamonu.edu.tr; muge_ertop@hotmail.com Funding information Gumushane University Scientific Research Projects Coordination Unit (GUBAP), Project Number: 16.F5115.03.01 Abstract The aim of this study was to optimize of the instant active dry yeast (A) and the dried chickpea sourdough (B) amount in bread formulation and to evaluate of usage possibilities of dried chickpea sourdough in bread production by examining some quality parameters.Response surface methodol- ogy was used to determine the effects of the variable factors (Aand B) on the product volume (V), acceptability value (AV) and pore factor (PF) of the bread. The usage rates were determined 0.63% for A and 10.21% for B.The bread produced according to optimized model (OB) was compared with control bread in terms of some quality parameters. The pore structures of bread samples and microtextural features obtained scanning electron microscopy during shelf life were examined by Image Analysis. Smaller and more homogeneous pore structures were obtained in the bread tex- ture; antioxidant activity, mineral content, microbial shelf life were improved, and the volume and crust thickness of the bread increased by the usage of chickpea sourdough. Practical applications Chickpea sourdough was dried in oven at low temperature short time condition.The protection of microbial vitality was ensure during the drying processes.The level of instant active dry yeast (A) and dried sourdough (B) were optimized with RSM. The usage rates were determined 0.63% for A and 10.21% for B.Optimized bread and control bread were compared in terms of various quality properties. The antioxidant activity, mineral content, microbial shelf life, and physicochemical prop- erties were improved. 1 | INTRODUCTION The chickpea sourdough is a traditional method also known as “sweet yeast” or “chickpea yeast” and is a well-known method used in various Mediterranean and Balkan countries. It is a kind of sourdough which has been used in bread making as a leavening agent and for imparting a distinctive flavor and taste. The chickpea sourdough may also prolong shelf life and provides functional, nutritional, and textural quality to bakery products (Hancıo glu-Sıkılı, 2003). Moreover, it can provide nutrients and functional compounds due to contains chickpea mass (Coda et al., 2015). The chickpea has a high-quality protein content and protein bioavailability due to its well-balanced amino acid composition than many of the several legume seeds (Roy, Boye, & Simpson, 2010). The chickpea is rich in Ca, P, Mg, K, and is also a good source of impor- tant vitamins such as riboflavin, niacin, thiamin, folate, the vitamin A precursor b-carotene and of the essential amino acids such as histidine which are deficient in wheat flour (Jukanti, Gaur, Gowda, & Chibbar, 2012; Shrivastava & Chakraborty, 2018; Zafar et al., 2015). In this respect, the usage of chickpea sourdough will satisfy consumers’ natural and healthy product expectations as a natural ingredient. The synthesis of microbial metabolites, activation of enzymes, acidification and proteolysis cause various changes during sourdough fermentation, which affect the dough and product. Moreover, they also affect enzyme activity, formation of bioactive peptides, level of pheno- lic acids, antioxidant activity, improve the bioavailability, functional and nutritional quality. Microbial metabolism during sourdough fermenta- tion may also produce new active compounds, such as peptides and amino acid derivatives with various functionalities, so the bioactivity is increased (Gobbetti, Rizzello, Di Cagno, & De Angelis, 2014). Some of previous studies have investigated the addition of pea, chickpea, or their flours to several bakery products such as chapatti, cakes (Gomez et al., 2008; Hera, Ruız-París, Ol ıete, & G omez, 2012), biscuits, J Food Process Preserv. 2018;e13650. https://doi.org/10.1111/jfpp.13650 wileyonlinelibrary.com/journal/jfpp V C 2018 Wiley Periodicals, Inc. | 1 of 10 Received: 7 January 2018 | Revised: 12 March 2018 | Accepted: 18 March 2018 DOI: 10.1111/jfpp.13650