Emerging Thermal and Nonthermal Technologies in Food Processing

Prem Prakash Srivastav, Deepak Kumar Verma, Ami R. Patel, Asaad Rehman Al-Hilphy, Prem Prakash Srivastav, Deepak Kumar Verma, Ami R. Patel, Asaad Rehman Al-Hilphy

• Publisher: Apple Academic Press
• Year: 2020
• eBook ISBN: 9781000023015
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Science General
• Index: Technology & Engineering

This new volume provides a comprehensive overview of thermal and nonthermal processing of food with new and innovative technologies. Recent innovations in thermal as well as nonthermal technologies, which are specifically applied for potable water and fluid foods (milk, juice, soups, etc.), are well documented for their high bioavailability of macro- and micronutrients and are very promising. This volume brings together valuable information on fluid and microbial characteristics and quality dynamics that facilitate the adoption of new technology for food processing.

Some new technologies and methods covered include the application of microwaves in heating, drying, pasteurization, sterilization, blanching, baking, cooking, and thawing; microwave-assisted extraction of compounds; using low-electric fields; alternation of temperature and pressure of supercritical carbon dioxide; ultrasound-assisted osmotic dehydration; hydrodynamic cavitation; high-pressure processing; gamma-irradiation; and more. The nonthermal technologies discussed have been developed as an alternative to thermal processing while still meeting required safety or shelf-life demands and minimizing the effects on nutritional and quality attributes.

CHAPTER 1

Evaluation of Thermal Processing in the Dairy Industry Using Milk Enzymes

LOREDANA DUMITRAŞCU, GABRIELA RÂPEANU, and NICOLETA STĂNCIUC

Faculty of Food Science and Engineering, “Dunărea de Jos” University of Galati, Galati, Romania,
E-mail: [email protected] (L. Dumitraşcu);
E-mail: [email protected] (G. Râpeanu);
E-mail: [email protected] (N. Stănciuc)

1.1 INTRODUCTION

Milk is one of the most complex food that contains mainly water, proteins, fats, carbohydrates, minerals, vitamins, and enzymes (Niamah and Verma, 2017; Verma et al., 2017). For centuries, milk is considered one of the most valuable natural food from the human diet (Al-Hilphy et al., 2016). On the other hand, milk nutrients, neutral pH and high water activity provide excellent conditions for many pathogenic microorganisms to be developed, whose multiplication is dependent on temperature and as well as on competing microorganisms (Claeys et al., 2014). Therefore, heat treatment should be applied to guarantee its microbial safety and stability. Moreover, the functional and nutritional properties of milk are changed during heating as a result of various competitive and interdependent reactions that are dependent on heating conditions, milk composition, and origin. The main heat treatments applied in dairy industry include: thermalization (57–68°C, 15–20 s), HTST pasteurization (71–74°C, 15–40 s), sterilization (110–120°C, 20 min.), indirect UHT (135–140°C, 6–10 s), direct UHT (140–150°C, 2–4 s) and ISI (innovative steam injection, 150–200°C, <0.1 s).

A comprehensive review was reported by Claeys et al. (2014), where the authors presented the risks and benefits associated with the consumption of raw and processed cow milk, considering microbiological and nutritional properties. Most of the dairy products available for consumption are obtained from cow milk. The increased interest of consumers for healthy diets generated increased attention for milk and dairy products of nonbovine origin, and especially for caprine and ovine origin. Caprine milk possesses stronger antimicrobial, immunological, and antibacterial system and higher digestibility compared with ovine or bovine milk (Slacanac et al., 2010). The growing interest in goat milk as an alternative food for infants with food allergies should be supported by appropriate studies showing its suitability for human consumption and in terms of milk safety. In most countries, assessment of the milk of non-bovine origin is not yet introduced in routine testing programs. Regulation (EC) 853/2004 lays down regulatory microbial criteria for total plate count and somatic cells, as well as health and hygienic requirements for animal production and production facilities, respectively. In regard to heat treatments applied in the dairy industry, European regulations are mainly based on microbiological platforms, which are time-consuming and expensive to control. Fast, easy control instruments to assess heating process efficiency and severity are scarce.

In the entitled chapter, research findings about some milk enzymes from the bovine and nonbovine origin are presented. Information regarding the activity of alkaline phosphatase (ALP), γ-glutamyltransferase (GT) and lactoperoxidase (LP) in bovine, caprine, and ovine milk, as well as the effect of milk species on the thermal inactivation of these enzymes, is briefly discussed.

1.2 TIME TEMPERATURE INDICATORS

Milk enzymes are distributed in different milk phases (Table 1.1), many of them possessing technological implications (Fox, 2006) as following:

1. Alteration (lipase, acid phosphatase, xanthine oxidase) or preservation (LP, sulphydryl oxidase, superoxide dismutase) of milk quality;

2. Indicators for the assessment of milk thermal processing (ALP, γ-GT, and LP);

3. Mastitis indicators (catalase, acid phosphatase, β-N-acetylglucosaminidase), whose concentration increase during mastitis infection;

4. Antimicrobial activity (lysozyme, LP);

5. Commercial source of enzymes (ribonuclease and LP).

TABLE 1.1 Indigenous Enzymes in Cow Milk

Enzyme	EC	Source	Distribution in Milk Phases
Plasmin	3.4.21.7	Blood	Mainly in casein micelles
Lysosomal Proteinases
Cathepsin D	3.4.23.5	Somatic cells	Acid whey
Cathepsin B	3.4.22.1
Other proteinases	-
Lipoprotein lipase	3.1.1.34	Mammary gland	Casein micelles
Phospohydrolases
Alkaline phosphatase	3.1.3.1	Mammary gland	Milk fat globule membrane / skim milk
Acid phosphatase	3.1.3.2
Ribonuclease	3.1.27.5	Blood	Serum
Oxidases
Lactoperoxidase	1.11.1.7	Mammary gland	Serum
Catalase	1.11.1.6	Somatic cells	Cream/skim milk
Xanthin oxidase	1.1.3.22	Blood	Milk fat globule membrane
Superoxide dismutase	1.15.1.1		Serum
γ-glutamyltransferase	2.3.2.2	Mammary gland	Membrane material in skim milk
N-acetyl-β-glucosaminidase	3.2.1.52	Somatic cells	Skim milk
Amylases (diastase, α...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• About the Editors
• Table of Contents
• Dedication
• Contributors
• Abbreviations
• Symbols
• Preface
• 1. Evaluation of Thermal Processing in the Dairy Industry Using Milk Enzymes
• 2. Microwave Heating: Alternative Thermal Process Technology for Food Application
• 3. Effects of Drying Technology on Physiochemical and Nutritional Quality of Fruits and Vegetables
• 4. Disinfection of Drinking Water by Low Electric Field
• 5. Removal Cholesterol from Minced Meat Using Supercritical CO2
• 6. Microwave-Convective Drying of Ultrasound Osmotically Dehydrated Tomatoes
• 7. Ultrasound-Assisted Osmotic Dehydration in Food Processing: A Review
• 8. Hydrodynamic Cavitation Technology for Food Processing and Preservation
• 9. High Pressure Processing (HPP): Fundamental Concepts, Emerging Scope, and Food Application
• 10. Induced Electric Field (IEF) as an Emerging Nonthermal Techniques for the Food Processing Industries: Fundamental Concepts and Application
• Index