Preface

Fermentation-based industrial and biotechnological processes have been the subject of study for centuries. In addition, some sectors, such as food and biofuel production, have highlighted fermentation-based processes, while seeking new flavors and new natural sources from which to obtain healthy natural compounds with high nutritional value in the case of food; or new natural sources for raw material for the production of bio-fuels as an alternative to fossil fuels.

Even so, there are certain limitations that make many of these processes inefficient and economically unprofitable. Examples of some of these limitations include the corrosion of bioreactors, for example, caused by certain conditions in highly ionic media; in other cases, the production of some secondary metabolites of interest is associated with the use of organic reagents and solvents that are contaminants.

Recently, advances in molecular biology techniques, massive data analysis, and new engineering technologies and processes have led to solutions to some of these problems. Nevertheless, many other issues remain unsolved and more study should be done in the next future to overcome them (fermentations on a large scale using extremophilic microorganism remains highly unexplored at the time of writing this book).

This book is aimed at addressing some recent examples of fermenting-based processes in which parameters and stages in production of several compounds by fermentation are optimized. The book contains eleven chapters written by international experts in the field of fermentation. The topics covered by the chapters are related to food and beverage fermentation, production of bio combustibles, and bioprocesses to produce cell therapy products among others. Consequently, this book contributes to the implementation of fermentation to obtain valueadded compounds in the market, which are low cost and low time consuming. The examples collected could be of interest not only to professionals and researchers in the field but also to students at the advanced undergraduate and graduate levels.

The editor gratefully all the authors, IntechOpen editorial staff as well as the author service manager and acknowledge that this book would never have been written without their valuable contribution. The editor hopes that the readers will enjoy the organization of the subject matter and find the book to be a valuable source of new information on the many and varied facets of fermentation-based processes.

**II**

**Section 4**

Heavy Metals

Outlook

Products

Mini-Bioreactors

*by Keukeu Kaniawati Rosada*

Other Applications **129**

**Chapter 7 131**

**Chapter 8 153** Lactic Acid Bacteria as Microbial Silage Additives: Current Status and Future

**Chapter 9 177** Development of an Anaerobic Digestion Screening System Using 3D-Printed

**Chapter 10 191**

**Chapter 11 203**

Biodegradability during Anaerobic Fermentation Process Impacted by

*by Yonglan Tian, Huayong Zhang and Edmond Sanganyado*

*by Pascal Drouin, Lucas J. Mari and Renato J. Schmidt*

*by Spyridon Achinas and Gerrit Jan Willem Euverink*

Streamlining the Fermentation Process Using Mixed Cultures

Bioprocess Development for Human Mesenchymal Stem Cell Therapy

*by Jan Barekzai, Florian Petry, Jan Zitzmann, Peter Czermak and Denise Salzig*

## **Rosa María Martínez-Espinosa**

Senior Lecturer, Biochemistry and Molecular Biology, Faculty of Science, University of Alicante, Alicante, Spain

**1**

Section 1

Introduction

Section 1 Introduction

**3**

**Chapter 1**

**1. Introduction**

enzymes [1].

to microbial flora [1, 3].

Introductory Chapter: A Brief

Overview on Fermentation and

Several authors stated that the word 'fermentation' comes from the Latin word *fermentare*, which means 'to leaven', while others confirm that it comes from the Latin verb *fervere*, which means 'to boil'. From these Latin terms, several definitions have been used so far to explain not only the concept of fermentation but also its applications. Thus, the earliest use of the word 'fermentation' mostly referred to natural metabolic processes driven by wild and unidentified microbes. Other more recent definitions state that fermentation is a process in which a substance breaks down into a simpler substance usually due to the metabolic activity of microorganisms like yeast or bacteria. In the context of physiology and biochemistry, fermentation processes are usually metabolic pathways producing modifications in organic molecules thanks to the action of microorganisms and/or

In the strict biochemical sense of the term, fermentation involves the action of anaerobic organisms on organic substrates. However, modern usage extends definition to the microbiological formation of smaller organic molecules, whether aerobic or anaerobic [2]. In applied fields like food or beverage production, fermentation involves any process conducted by microbial activities which brings about a desirable change to a foodstuff or beverage. The component products of fermentation may be isolated from the feedstock and purveyed as pure substances, unlike fer-

From the very beginning, microorganisms were described as the main organisms able to carry out fermentation, but, in general, fermentation is widely distributed in nature. From a biological point of view, fermentation is a way of extracting energy from molecules, and it is one of the common metabolic processes to all living beings: bacteria, archaea and eukaryotes. Thus, fermentation provides ATP thanks to the degradation of organic nutrients (usually under anoxic conditions). In animals for instance, fermentation occurs within the gastrointestinal tracts thanks

Fermentation-based processes have been of great interest for humans since the antiquity due to their potential applications. The origins of fermentation are difficult to track down, and it is assumed that the first fermentation process was discovered accidentally when salt was incorporated with food. Few historians have traced signs of fermentation dating as far back as 7000 BC. At that time, human beings made fermented foods like beer, wine, leavened bread (made primarily by yeasts) and cheeses (made by bacteria and moulds) since Neolithic times in West regions. These societies were soon followed by East Asian regions (6000–1500 BC), where

Challenges for the Next Future

*Rosa María Martínez-Espinosa*

mentation of antiquity (e.g. ethanol vs. wine).
