Characterization of Artisanal Spontaneous Sourdough Wheat Bread from Central Greece: Evaluation of Physico-Chemical, Microbiological, and Sensory Properties in Relation to Conventional Yeast Leavened Wheat Bread.

Pavlina Katsi,Sofia Michailidou,Anagnostis Argiriou,Ioanna S Kosma,Michael G Kontominas,Anastasia V Badeka

doi:10.3390/foods10030635

Abstract

In the present study, both yeast leavened bread (YLB) and artisanal sourdough wheat bread (SDB) were prepared. The physico-chemical, microbiological, and sensory properties of breads were monitored as a function of storage time (T = 25 °C). As expected, the titratable acidity (TA) values of SDB were higher than those of YLB. The aroma profile of SDB was similar to that of YLB, including classes of compounds such as alcohols, aldehydes, ketones, esters, organic acids, terpenes, and sulfur compounds; however, the concentrations between the two were different. Aroma deterioration of bread during storage was partly related to the loss of several volatiles. Texture and sensory analysis showed that SDB was harder, less elastic, but richer in aroma and light sour taste than YLB. Mold growth was apparent when the population of yeasts/molds reached approximately 4 log cfu/g. This yeast/mold count was reached on days 4–5 for YLB and day 18 + for SDB. A 16S amplicon meta-barcoding analysis showed that the bacterial profile of SDB was dominated by a single genus, (Lactobacillus). Analysis of the eukaryotic load showed that at the genus level, Saccharomyces and Alternaria were the most abundant genera, independently of the gene sequenced (18S or ITS). Based primarily on mold growth and texture data, which proved to be the most sensitive quality parameters, the shelf life was ca. 4–5 days for YLB and 10 days for SDB.

Highlights

Bread is probably the oldest “processed” food product
Total viable counts (TVC) exceeded the value of 6.0 log cfu/g, which was considered as the upper microbiological limit for bakery products, as defined by the International Commission on Microbiological Specifications for Foods (ICMSF) [28]
16S analysis showed that the bacterial profile of sourdough was dominated by a single genus, (Lactobacillus), whereas the eukaryotic load showed that at the genus level, Saccharomyces and Alternaria were the most abundant genera, independently of the gene sequenced (18S or ITS)

Summary

Introduction

Bread is probably the oldest “processed” food product. Industrial wheat bread production started at the beginning of the 20th century after the introduction of baker’s yeast as a superior leavening agent to sourdough and brewer’s yeast. The use of sourdough in bread production has been largely abandoned until very recently when consumer demand for the consumption of more natural bakery products with improved sensory properties and an extended shelf life, has revived the bakery industry’s interest in using sourdough for breadmaking. According to Ganzle and Gobbetti [2], the advantages of using sourdough in bread making include acidification, improvement of dough properties, improvement of texture, flavor, leavening capacity, delayed staling, and increased resistance to microbial spoilage

Objectives

Methods

Results

Conclusion