Non-Thermal Processing Technologies for the Grain Industry

M. Selvamuthukumaran

• Publisher: CRC Press
• Year: 2021
• Print ISBN: 9780367608576
• eBook ISBN: 9781000412338
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Food Science
• Index: Technology & Engineering

Food can rapidly spoil due to growth of microorganisms, and traditional methods of food preservation such as drying, canning, salting, curing, and chemical preservation can affect the quality of the food. Nowadays, various non-thermal processing techniques can be employed in grain processing industries to combat this. They include pulsed electric field processing, high pressure processing, ultrasonic processing, cold plasma processing, and more. Such techniques will satisfy consumer demand for delivering wholesome food products to the market. Non-Thermal Processing Technologies for the Grain Industry addresses these many new non-thermal food processing techniques that are used during grain processing and minimize microbial contamination and spoilage.

Key Features:

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• Explains the mechanism involved in application of cold plasma techniques for grain processing, and its strategy for inactivation of microbes by using this technique

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• Deals with the effect of incorporation of electric pulses on quality aspects of various grain based beverage products.

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• Details the innovative high pressure processing techniques used for extraction of antioxidant from food grains

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• Explores the safety issues and applications of non-thermal food processing techniques

This book will benefit food scientists, food process engineers, academicians, students, as well as anyone else in the food industry by providing in-depth knowledge and emerging trends about non-thermal processing techniques in various grain-based food processing industries.

Chapter 1 Recent Advances in Non-Thermal Food Processing Technology for Grain Industries

Yadigar Seyfi, Gökçen Baykuş and Sevcan Unluturk

Contents

1.1 High Hydrostatic Pressure Processing (HHP)

1.1.1 Description of the Process

1.1.2 Current Commercial Status of HHP Processing

1.1.3 HHP Processing of Grains

1.1.3.1 Effects of HHP on Microbial Quality of Grains

1.1.3.2 Effects of HHP on Grain Quality, Components and the Germination and Quality of Sprouted Grains

1.1.4 Regulations

1.1.5 Research Needs and Challenges

1.2 Pulsed Electric Field (PEF)

1.2.1 Description of the Process

1.2.2 Current Commercial Status of PEF Processing

1.2.3 PEF Processing of Grains

1.2.3.1 Effect of PEF on Microbial Quality of Grains

1.2.3.2 Effects of PEF on Grain Quality and Components

1.2.3.3 Effects of PEF on Germination and Quality of Sprouted Grains

1.2.4 Regulations

1.2.5 Research Needs and Challenges

1.3 Ozone Technology

1.3.1 Description of the Process

1.3.2 Current Commercial Status of Ozone Processing

1.3.3 Ozone Processing of Grains

1.3.3.1 Effects of Ozone on Microbial Quality of Grains

1.3.3.2 Effects of Ozone on Grain Quality and Components

1.3.3.3 Effects of Ozone on Germination and Quality of Sprouted Grains

1.3.4 Regulations

1.3.5 Research Needs and Challenges

1.4 Radiation

1.4.1 Ionizing Radiation (IR)

1.4.1.1 Description of the Process

1.4.1.2 Current Commercial Status of Ionizing Radiation Processing

1.4.1.3 Effects of Irradiation on Microbial Quality of Grains

1.4.1.4 Effects of Irradiation on Grain Quality and Components

1.4.1.5 Regulations

1.4.2 Nonionizing Radiation

1.4.2.1 Description of the Process

1.4.2.2 Research Needs and Challenges

1.5 Non-Thermal Plasma (Cold Plasma) Processing

1.5.1 Description of the Process

1.5.2 Current Commercial Status of NTP Processing

1.5.3 NTP Processing of Grains

1.5.3.1 Effects of NTP on Microbial Quality of Grains

1.5.3.2 Effects of NTP on Grain Quality and Components

1.5.3.3 Effects of NTP on Germination and Quality of Sprouted Grains

1.5.4 Regulations

1.5.5 Research Needs and Challenges

1.6 Ultrasound

1.6.1 Description of the Process

1.6.2 Current Commercial Status of Ultrasound Processing

1.6.3 Ultrasound Processing of Grains

1.6.3.1 Effects of Ultrasound on Microbial Quality of Grains

1.6.3.2 Effects of Ultrasound on Germination and Quality of Sprouted Grains

1.6.4 Regulations

1.6.5 Research Needs and Challenges

Bibliography

1.1 High Hydrostatic Pressure Processing (HHP)

Research into the effects of high pressures on food dates back to 1899. Bert Hite was the first to design and construct a high-pressure unit for the pasteurization of milk and other food products (Hite 1899). On the other hand, industrial-level usage of HHP devices dates back to the 1990s. The first industrial HHP equipment was installed in 1991 in Japan (Knorr et al. 2011). Some jams, salad dressings, sauces, fruit yogurts and juices are some of the food products processed with HHP. HHP-treated foods have been marketed in Europe and the USA since 1996 (Ortega-Rivas 2012).

High hydrostatic pressure processing (HHP), also known as ultrahigh-pressure processing or pascalization, is a novel non-thermal technology for the food industry. Simply, HHP is a process that is applied to prevent microbial multiplication and improve food quality. The applied pressure may range from 100 to 1000 MPa (whereas the normal atmospheric pressure is equal to 0.1 MPa) (Arora and Chauhan 2019). When heat is applied to foodstuffs, protein and starch are denatured and enzymes and microorganisms become inactivated. The same effect occurs when foods are exposed to extremely high pressures. However, unlike heat treatment, the food’s sensory properties are not affected by HHP treatment and microorganisms are inactivated without causing significant changes to the nutritional properties of foods (Ortega-Rivas 2012).

1.1.1 Description of the Process

Hydrostatic pressure is generated in closed systems by heating or mechanical volume reduction. Basically, the HHP process relies on two principles: the isostatic rule and Le Chatelier’s principle. According to the isostatic rule, pressure transmission is instantaneous and uniform throughout the food. Le Chatelier’s principle states that when a system at equilibrium is disturbed, it returns to equilibrium by countering the disturbance (Hogan, Kelly and Sun 2005).

In an HHP process, the food product to be treated is placed in a pressure vessel capable of supplying the required pressure; the product is submerged in a liquid, which acts as the pressure-transmitting medium. Other than water, liquids containing castor oil, silicone oil, sodium benzoate, ethanol or glycol are also used as the pressure-transmitting medium. HHP equipment mainly consists of a pressure vessel, two end closures, a yoke (a structure used for restraining end closures while under high axial pressure), a pressure-creating device, instrumentation and controls (pressure, temperature, flow and level measurements) (Arora and Chauhan 2019; Naik et al. 2013).

This technology has been adapted from the chemical industry, where pressure is utilized to increase the reaction yield. It has been shown that pressures higher than 400 MPa damage intermolecular and intramolecular bonds (Ortega-Rivas 2012). HHP processing results in some changes to the food structure including protein and enzyme denaturation, starch modification, etc. HHP also results in the inactivation of undesired microorganisms (pathogenic and spoilage) in the food. This is an important consideration for any preservation method (Hogan, Kelly and Sun 2005). Although spores can withstand pressure up to 1,200 MPa, HHP has the ability to inhibit many vegetative cell types (Zhang et al. 2011).

1.1.2 Current Commercial Status of HHP Processing

Industrial HHP application is a batch or semi-continuous process. The choice of equipment depends on the type of food product to be processed. Solid food products or foods with large solid particles can only be processed in batch mode. Liquids, slurries and other pumpable products additionally have the option of semi-continuous production (Hogan, Kelly and Sun 2005).

In today’s world, there are many countries that produce lab-scale, pilot-scale or commercial-scale HHP units. These are the USA, Japan, China, Spain, France, Sweden, Poland, Germany, the Netherlands and the UK (Arora and Chauhan 2019).

1.1.3 HHP Processing of Grains

1.1.3.1 Effects of HHP on Microbial Quality of Grains

Food preservation techniques have two main goals: the eradication of pathogenic microorganisms to ensure food safety and the inactivation of spoilage microorganisms to provide food stability and increase the shelf life of the foods (Hogan, Kelly and Sun 2005). It has been found that the effect of high pressure on microorganisms is similar to that of high temperature (Ortega-Rivas 2012).

A number of factors such as the type of microorganism, temperature, magnitude, duration of the HHP treatment and composition of the food affect the microbial inactivation provided by HHP. By considering these factors, appropriate pressure treatment should be applied to assure the inactivation of spoilage, pathogenic and vegetative cells of microorganisms present in foods (Arora and Chauhan 2019).

The effect of high pressure on microbial inactivation is primarily due to cell membrane permeability (Hogan, Kelly and Sun 2005; Ortega-Rivas 2012). A number of studies have shown that high pressure affects all types of vegetative cells rather than spores. For example, Fusarium is an important strain of phytopathogenic fungi causing economic losses. Several Fusarium species can infect small grains such as wheat, barley, oat and maize (Ferrigo, Raioala and Causin 2016). Fungal contamination can spread rapidly during storage if conditions are suitable. Mycotoxins produced by fungi and their contamination cause both product losses and health hazards (Schmidt, Zannini and Arendt 2018). Several strategies have been developed to prevent mycotoxin accumulation in cereals. For instance, Schmidt et al. (2018) investigated the effect of 13 different treatments on commercial hard winter whe...

Table of contents

• Cover
• Half-Title
• Title
• Copyright
• Contents
• Preface
• About the Editor
• Contributors
• 1 Recent Advances in Non-Thermal Food Processing Technology for Grain Industries
• 2 Current Trends in the Use of Pulsed Electric Fields for Quality Retention in Grain-Based Beverages
• 3 Innovative Approaches in High-Pressure Processing for the Extraction of Antioxidants from Grains
• 4 Applications of Cold Plasma Technology in Grain Processing
• 5 Ultrasonic Applications in Bakery and Snack Food Processing Industries
• 6 Application of Ozone Technology for Grain Processing Industries
• 7 Effects of an Oscillating Magnetic Field on the Stability of Stored Grain Produce
• 8 Grain-Based Functional Food Production
• 9 Effects of Dense Phase CO2 Application on Microbial Stability in Grain-Based Beverages and Food Products
• 10 Packaging Requirements for Non-Thermal Processed Grain-Based Foods
• 11 Impact of Organoleptic and Consumer Acceptability for Non-Thermally Processed Grain-Based Food Products
• 12 Safety Issues for Non-Thermal Food Processing Applications in Grain Industries
• Index