Food Biochemistry and Food Processing (2 edition)

BLBS102-c31 BLBS102-Simpson March 21, 2012 14:0 Trim: 276mm X 219mm Printer Name: Yet to Come

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Bakery and Cereal Products

J. A. Narvhus and T. Sørhaug

Introduction

Cereal Composition

Starch

Protein

Gluten Proteins

Enzyme Proteins

Amylases

Proteases

Lipases

Lipids

Bread

Bread Formulation

The Development of Dough Structure

Dough Fermentation

Commercial Production of Baker’s Yeast

Desirable Properties of Baker’s Yeast

The Role of Yeast in Leavened Bread

The Bread-Baking Process

Staling

Sourdough Bread

Advantages of Making Sourdough Bread

Microbiology of Sourdough

Starters

Sourdough Processes

Selection and Biochemistry of Microorganisms in

Sourdough

Carbohydrate Metabolism

Co-metabolism

Proteolysis and Amino Compounds

Volatile Compounds and Carbon Dioxide

Antimicrobial Compounds from Sourdough LAB

Traditional Fermented Cereal Products

The Microflora of Spontaneously Fermented Cereals

Desirable Properties of the Fermenting Microflora

Microbiological and Biochemical Changes in Traditional

Fermented Cereals

Fermented Probiotic Cereal Foods

References

INTRODUCTION

Cereals are the edible seeds of plants of the grass family. They

can be grown in a large part of the world and provide the staple

food for most of mankind. Maize, wheat, and rice contribute

about equally to 85% of world cereal production, which is at

present about 2000 million tons (FAO 1999).

Cereals in their dry state are not subjected to fermentation due

to their low water content. Properly dried cereals contain less

than 14% water, and this limits microbial growth and chemical

changes during storage. However, on mixing grains or cereal

flour with water or other water-based fluids, enzymatic changes

occur that may be attributed to the enzymes inherent in the

grain itself and/or to microorganisms. These microorganisms

can either be those present as the natural contaminating flora of

the cereal, or they can be added as a starter culture.

This chapter will be mainly devoted to fermented bakery prod-

ucts made from wheat. However, on a global basis, many fer-

mented cereal products are derived wholly or in part from other

grains such as rice, maize, sorghum, millet, barley, and rye.

Different cereals differ not only in nutrient content, but also in

the composition of the protein and carbohydrate polymers. The

functional and sensory characteristics of products made from

different cereals will therefore vary at the outset due to these

factors. In addition to this, the opportunity to vary technological

procedures and microbiological content and activity provides

us with the vast range of fermented cereal products that are

prepared and consumed in the world today.

CEREAL COMPOSITION

Carbohydrates are quantitatively the most important constituents

of cereal grains, contributing 77–87% of the total dry matter.

In wheat, the carbohydrate in the endosperm is mainly starch,

whereas the pericarp, testa, and aleurone contain most of the

Food Biochemistry and Food Processing, Second Edition. Edited by Benjamin K. Simpson, Leo M.L. Nollet, Fidel Toldr ́a, Soottawat Benjakul, Gopinadhan Paliyath and Y.H. Hui.

©C2012 John Wiley & Sons, Inc. Published 2012 by John Wiley & Sons, Inc.

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