Microbial Enzyme Technology in Food Applications

Ramesh C. Ray, Cristina M. Rosell, Ramesh C. Ray, Cristina M. Rosell

• Publisher: CRC Press
• Year: 2017
• ISBN:
  9781315351414
• Edition: 1
• Topic: Biological Sciences
• Subtopic: Microbiology
• Index: Biological Sciences

The aim of food processing is to produce food that is palatable and tastes good, extend its shelf-life, increase the variety, and maintain the nutritional and healthcare quality of food. To achieve favorable processing conditions and for the safety of the food to be consumed, use of food grade microbial enzymes or microbes (being the natural biocatalysts) is imperative.

This book discusses the uses of enzymes in conventional and non-conventional food and beverage processing as well as in dairy processing, brewing, bakery and wine making. Apart from conventional uses, the development of bioprocessing tools and techniques have significantly expanded the potential for extensive application of enzymes such as in production of bioactive peptides, oligosaccharides and lipids, flavor and colorants. Some of these developments include extended use of the biocatalysts (as immobilized/encapsulated enzymes), microbes (both natural and genetically modified) as sources for bulk enzymes, solid state fermentation technology for enzyme production. Extremophiles and marine microorganisms are another source of food grade enzymes. The book throws light on potential applications of microbial enzymes to expand the base of food processing industries.

PART 1

HISTORY

1

Microbial Enzymes in Food Applications

History of Progress

Swati S. Mishra,^1,* Ramesh C. Ray,² Cristina M. Rosell³ and Debabrata Panda¹

¹ Department of Biodiversity and Conservation of Natural Resources, Central University of Orissa, Koraput 764020, India; E-mail: [email protected]; [email protected]

² ICAR-Regional Centre of Central Tuber Crops Research Institute, Bhubaneswar 751019, India.

E-mail: [email protected]

³ Food Science Department, Institute of Agrochemistry and Food Technology, Avda Agustín Escardino Paterna, Valencia, Spain; E-mail: [email protected]

* Corresponding author

1. Introduction

It seems now clear that a belief in the functional importance of all enzymes found in bacteria is possible only to those richly endowed with faith.

—Marjory Stephenson (Biochemist)

Enzymes are very important for sustainability of life in all life forms. They act as catalysts in chemical reactions. Microbial enzymes are of great importance in the development of industrial bioprocesses as they play a crucial role as metabolic catalysts. Enzymes have been applied in food preservation for millennia, and today they are enabling various food industries to provide the quality and stability of their products, with increased production efficiency. Microbial enzymes in food applications have not only diversified the food industry but also produced economic assets. The increasing demand for sustainable food has given an increasing drive to the use of microbial enzymes, knowingly or unknowingly since ages. Microorganisms have always been the largest and useful sources of many enzymes (Demain, 2008). They also provide environmental-friendly products to consumers, reducing consumption in energy, water and raw materials and generating less waste. Enzymes contribute to industrial processes by reducing energy consumption and maximizing its efficiency while contributing to its sustainability profile.

Although not in isolated form, enzymes have been used traditionally in dairy, baking, brewing and winemaking for centuries (Kirk et al., 2002). Their applications keep the bread soft and fresh for long, increase the dough volume and give a crispy crust (Rosell and Dura, 2016). Since time immemorial, enzymes are used in beer and wine to lower the calorie and alcoholic contents and also for more clarity and enhancement of flavour. Though used for centuries unknowingly, the revolution in food industry has been established by the use of enzymes or a whole microbial cell as the biocatalyst. The microbial enzyme has a high industrial and commercial application (Adrio and Demain, 2005). Microbes have proven to be the most useful and largest source of enzymes (Demain and Adrio, 2008). The current article covers the major developments in essential microbial enzyme production and applications in food industry.

2. Enzymes

An enzyme in purified form is a protein which is synthesized as an intra- and extra-cellular compound and may or may not possess non-protein prosthetic group (Vallery and Devonshire, 2003). Enzymes enhance the reaction rate with high specificity as they catalyzes biochemical reactions. All enzymes known (except ribozymes) are proteins which are high molecular-weight compounds made from chains of amino acids linked by peptide bonds. Enzymes are classified by the type of reaction they catalyse and the substance (called substrate) they act upon. It is customary to attach the suffix ‘ase’ to the name of the principal substrate upon which the enzyme acts (Bennett and Frieden, 1969). For example, lactose is acted upon by lactase, proteins by proteases and lipids by lipases. Also enzymes have common names, such as papain, from papaya.

2.1 History of enzymes

Enzymes in history were known as ‘biocatalysts’, which helped to accelerate the biological or biochemical reaction. The term ‘enzyme’ was first used in 1877, by Wilhelm Friedrich Kuhne, Professor of Physiology at University of Heidelberg, in his paper to the HeidelbergerNatur-Historischen und Medizinischen Verein, suggesting that such non-organized ferments should be called enzymes (Kuhne, 1876). It was derived from a Greek term ‘ενζυμον’ meaning ‘in leaven’ or ‘in yeast’ (Kuhne, 1877). Though enzymes have been used by mankind since centuries, they were technically termed as ‘enzymes’ only in the 18th century.

Before the nature and function of enzymes were understood, the practical applications were established as there were many ancient uses of enzymes, like barley malt for conversion of starch in brewing or calf stomach as a catalyst in the manufacture of cheese. Later on, many scientists reported on enzymes in different forms, for example, Spallanzani in about 1783, showed that the gastric juice secreted by cells could digest meat in vitro and whose active substance was named as pepsin by Schwann in 1836 (Perham, 1976). The first enzyme to be discovered was ‘diastase’ by a French scientist, Payen in the year 1833, when he found it catalyzes the breakdown of starch into glucose in malt. James B. Sumner of Cornell University obtained the first enzyme in pure form, called ‘urease’, in 1926. He received the Nobel Prize in 1947 for isolating and crystallizing the enzyme urease from jack bean. The discovery of a complex procedure for isolating pepsin by John H. Northrop and Wendell M. Stanley of the Rockefeller Institute for Medical Research earned them the 1947 Nobel Prize as well. This precipitation technique has been used to crystallize several enzymes (Pfeiffer, 1954). Table 1 shows the periodic development of microbial enzymes over the centuries.

Table 1. Periodic development in microbial enzyme (for foods and beverages) utilization over centuries.*

Period	Events
2000 BC	Fermentation was developed mainly for use in brewing, bread baking and cheese-making by the Sumerians and Egyptians.
800 BC	The enzyme chymosin and calves’ stomach were used for cheese-making.
1836 AD	Schwann discovered pepsin.
1856 AD	Berthelot showed enzymes require cofactor or co-enzyme for activity.
1860 AD	Berthelot demonstrated hydrolytic enzymes, including invertase (β-fructofuranosidase) obtained from Saccharomyces cerevisiae.
1878	Term ‘enzyme’ was derived from the Greek term ‘ενζυμον’ meaning ‘in yeast’; also the components of yeast cells was identified which cause fermentation.
1894	Takamine first time patented a method (koji process; SSF) for preparation of diastatic enzymes (mostly α-amylase) from the mould that was marketed under the name ‘Takadiastase’.
1913	Patents were awarded to French scientist A. Boidin and Belgian scientist Jean Effront for production of bacterial (Bacillus subtilis and B. mesenterieus) amylases and diastases as still culture (surface film).
1926	Enzymes were initially shown to be proteins.
1946	Commercially amylases were produced using Aspergillus oryzae strain by Mould Bran Co., Iowa, USA in SSF process.
1950	Amylase production in SmF using Tank Bioreactor at Northern Regional Laboratory, USDA, Illinois, USA; shift over from SSF to SmF.
1959	Bio 40-protease from B. subtilis was introduced in the market.
1950–1980	Spectacular increase in industrial enzyme production, particularly amylases and proteases (to a larger extent) and pectinases, lactase, invertase, lipase and cellulases (to lesser extent).
1965	International Union of Biochemistry set up ‘Enzyme Commission’ to publish enzyme classification.
1980s	Animal feed with improved nutrient availability and digestibility were developed through enzyme preparations.
1982	A product of gene technology, alpha amylase, was developed for application in food for the first time.
1988	An early approval of a product of gene technology, recombinant chymosin for food use was approved and introduced in Switzerland.
1990	Gene technology was used by developing two food processing aids—an enzyme for use in cheese-making in the US and a yeast used in baking in the UK.
2000-onwards	Re-designing microbial enzymes by tailoring their protein sequence.

* Source: Rose (1980), Behera and Ray (2015), Joshi and Satyanarayana (2015), Panda and Ray (2015), Panda et al. (2016)

2.2 Microbial enzymes

Like all living cells, microbes also produce enzymes which are hydrolyzing, oxidizing, reducing or metabolic in nature, but the amount of enzyme produced differs in various species and strains. Hence for commercial production of specific enzymes, a particular strain is to be selected that has the maximum enzyme activity. Enzymes from microbial sources are more advantageous than their equivalents from plant and animal sources because of lower production cost as compared to others, production on a large-scale, better scope for genetic manipulation, rapid culture development, less material use, being environment friendly and due to a wide range of physical and chemical characteristics; hence, they are preferred in various industrial applications (Hasan et al., 2006). Important progress in the food industry is mainly attributed to the use of microbial enzymes. Nowadays, enzymes are increasingly use...