Food Biochemistry and Food Processing (2 edition)

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Enzymes in Food Analysis


Isaac N. A. Ashie


Introduction
Analysis of the Major Food Components
Proteins and Amino Acids
Sugars
Other Food Components
Alcohol
Cholesterol
Antioxidants
Organic Acids
Analysis of Food Contaminants
Pharmaceuticals
Food Toxins
Endogenous Toxins
Process-Induced Toxins
Environmental Toxins
Enzymatic Analysis of Food Quality
Concluding Remarks
References

Abstract:Foods are primarily very complex matrices and there-
fore present an enormous technical challenge to the analyst whose
responsibility is to determine and establish the levels of various
components therein. A number of analytical tools, including en-
zymes, have therefore been developed through the years to meet this
challenge. The basis for enzyme use is its specificity that enables
selective, sensitive, and accurate determination of both macro- and
micronutrients in foods. The application of enzymes as an analytical
tool has, in recent years, been given a further boost by the devel-
opment of biosensors with improved robustness and versatility. In
this chapter, the application of enzymes (e.g., proteases, amylases,
lipases, oxidases, etc.) and the underlying principles for analysis of
food macro- and micronutrients including proteins, carbohydrates,
lipids, antioxidants, cholesterol, toxins, food contaminants (phar-
maceuticals, and food quality) are discussed.

INTRODUCTION


For centuries and prior to enzyme discovery and scientific under-
standing of its catalytic activity, humans had been inadvertently
tapping into the benefits of enzymes for the production of a va-
riety of foods. It is hard to think of food products like cheese,
bread, wine, and other alcoholic beverages today without con-
sidering the role of enzymes in their production. Since their
discovery, the unique characteristics of enzymes, such as their
natural origins and specificity, have been exploited in the pro-
cessing of a plethora of foods. These processes include (1) starch
liquefaction and saccharification using alpha amylases and amy-
loglucosidases, (2) conversion of dextrins to fermentable sugars
in brewing, (3) chill-haze prevention in the brewing industry us-
ing proteases, (4) juice clarification using pectinases, and (5) pro-
duction of high-fructose corn syrups by conversion of glucose to
its much sweeter keto-form, fructose, using glucose isomerase,
just to mention a few. Recent developments in the field of molec-
ular biology and protein engineering have enabled cost-effective
production of “customized” enzymes with tailored characteris-
tics that have further broadened the range of food applications
involving enzymes. For example, phospholipases for increasing
cheese yield and oil degumming, lipases for interesterification
of lipids as an alternative to chemical processes, carbohydrate
oxidases for lactose conversion to lactobionic acid used in the
transplant industry for organ preservation, and asparaginases for
acrylamide mitigation in foods are some of the emerging appli-
cations of enzymes in the food manufacturing process.
The broad range of enzyme classes used in the manufac-
ture of food products is a very good indicator of the challenges
presented to the food analyst, whose responsibility is to ana-
lyze the ingredients or components of different foods. Foods
are basically a complex matrix of edible ingredients, some of
which are present in high amounts (e.g., macronutrients such as

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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