Food Biochemistry and Food Processing (2 edition)

BLBS102-c39 BLBS102-Simpson March 21, 2012 14:20 Trim: 276mm X 219mm Printer Name: Yet to Come

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Minimally Processed Foods

Michael O. Ngadi, Sammy S.S. Bajwa, and Joseph Alakali

Introduction

Overview of Thermal Processing Techniques

High Temperature Short Time Process

Aseptic Processing

Sous-Vide Processing

Electrical Heating of Foods

Ohmic Heating

Dielectric Heating

Nonthermal Processing Technologies

High-Pressure Processing

Pulse Electric Field Processing

Low-Dose Irradiation

Ultrasound

UV Irradiation

Other Techniques

Quality and Safety Considerations: The Hurdle Concept

Microbial Stress

Multitarget Preservation of Foods

Limitations of Hurdle Concept

Packaging Techniques for Minmally Processed Foods

Map

Active and Edible Packaging

Conclusion

References

Abstract:The widespread, strong and consistent demands for fresh-

like and safe food products have been among the major factors

driving innovative food processing technologies. The sometimes

divergent requirements for food quality and safety have contin-

ued to challenge food scientists and engineers. Minimally pro-

cessed foods are produced without or with mild heat treatment

that result in safe products without quality degradation. To produce

these products, nonthermal technologies are being introduced to re-

place or complement the well-established thermal processes. Tech-

niques that combine different mild hurdles to restrict the growth

of food spoiling microorganisms are also used. The hurdles are

typically applied in a logical sequence to take advantage of pos-

sible synergistic interactions between them to enhance safety and

quality of food products. The various techniques of minimal pro-

cessing of foods are reviewed in this chapter along with the re-

quired packaging considerations that are needed for the processed

products.

INTRODUCTION

The normal objective of food processing is to transform a prod-

uct to ensure that it has adequate nutrient content, acceptable

to consumers with respect to sensory and functional properties,

and that it is microbiologically and chemically safe to consume.

Thus, humans have traditionally embarked on series of activi-

ties and have taken advantage of various techniques, including

various types of cooking, smoking, fermenting, sun drying, and

salt preservation to transform food products. Nicolas Appert’s

introduction of canning and thermal processing revolutionized

and set the stage for the modern food processing industry. De-

spite the huge market for canned and processed foods, there

is strong and increasing demand for fresh and minimally pro-

cessed health-centered foods. This demand for products with

fresh-like characteristics has changed the traditional food pro-

cessing mantra. New and lucrative markets are being developed

for “fresh or fresher foods” that are “high” or “low” in certain

target constituents (e.g., less salt, fat and sugar; and more in

fiber and health-promoting chemicals). This rise in consumer

health consciousness can be attributed to wide societal and sci-

entific reawakening to the benefits of fresh products, including

fruits and vegetables (Allende et al. 2006). Fresh fruits and

vegetables are known to be of higher quality and rich in an-

tioxidants, which are crucial in the fight against cancer (Flood

et al. 2002). However, the recent and increasing incidences of

food-borne pathogens in food products have heightened the alert

for increased food safety. Although Canada has one of the best

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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