Buy Now and Pay in EMI's

DRYING TECHNOLOGIES FOR FOODS: FUNDAMENTALS & APPLICATIONS: PART 3

Prabhat K Nema, Barjinder Pal Kaur, Arun S. Mujumdar
  • Country of Origin:

  • Imprint:

    NIPA

  • eISBN:

    9789389992083

  • Binding:

    EBook

  • Number Of Pages:

    400

  • Language:

    English

Individual Price: 3,800.00 INR 3,420.00 INR + Tax

Add to cart Contact for Institutional Price
 

Drying is an important unit operation used in the industry for processing and preservation of food products. Food industry always looks for cost effective and energy efficient drying techniques to commercially succeed in their ventures and to fulfill demand of high quality dried food products. Although a large volume of technical literature is available on drying of foods, it is still quite challenging for scientists and engineers to improve upon the existing drying systems and quality of the products. The book consists of 14 chapters detailing freeze drying, atmospheric freeze drying, swell drying, multi-flash drying, electro-hydrodynamic drying, pulse combustion drying, foam mat drying, ultrasound- assisted drying and fluidized bed drying. It also includes chapters which are commodity-specific such as mushroom drying, drying and roasting of cocoa and coffee beans. The degradation mechanism and kinetics of vitamin C degradation in fruits and vegetables, kinetics modeling of drying process for the recovery of bioactive compounds and energy calculation procedures for dryers is also covered which would be helpful to improve dryer operation and efficiency.

0 Start Pages

Preface Drying is an important unit operation used in the industry for processing and preservation of food products. Food industry always looks for cost effective and energy efficient drying techniques to commercially succeed in their ventures and to fulfill demand of high quality dried food products. Although a large volume of technical literature is available on drying of foods, it is still quite challenging for scientists and engineers to improve upon the existing drying systems and quality of the products. The first part of the book ‘Drying Technologies for Foods: Fundamentals and Applications’ covers fundamental principles of different drying techniques such as spray drying, microwave drying, superheated steam drying, heat pump drying, solar and impingement drying etc. The second part of this book offers comprehensive review of various novel drying techniques such as refractance window dehydration, supercritical drying as well as PCM-based solar dryers, vacuum dryers etc. In continuation of this series a third part is presented with the aim of providing in depth information about the drying technologies not covered in the earlier two parts. This book consists of 14 chapters detailing freeze drying, atmospheric freeze drying, swell drying, multi-flash drying, electro-hydrodynamic drying, pulse combustion drying, foam mat drying, ultrasound- assisted drying and fluidized bed drying. It also includes chapters which are commodity-specific such as mushroom drying, drying and roasting of cocoa and coffee beans. The degradation mechanism and kinetics of vitamin C degradation in fruits and vegetables, kinetics modeling of drying process for the recovery of bioactive compounds and energy calculation procedures for dryers is also covered which would be helpful to improve dryer operation and efficiency. The encouraging response to parts 1 and 2 of this set has been a great motivating factor to prepare this part, where again the emphasis is on up-to-date information on the topic with clear and concise presentation for better understanding by students, researchers, teachers, scientists and engineers. We are greatly thankful to our readers for constructive inputs and suggestions for further improvement of the quality of book set are always welcome. The editors wish to sincerely acknowledge the authors for their invaluable contributions to the part 3 of this book series. These authors are leading scientists, engineers and experts from different parts of the world. Each of the invited contributors in this book has worked extensively in the respective area of drying technology and hence their strong experience in the form of chapter will benefit the readers. We are pleased to thank all of them for their great contributions in this book. We also thankfully acknowledge the kind guidance and support received from Dr Chindi Vasudevappa, Vice Chancellor of NIFTEM during the process of completing this book.

 
1 Freeze Drying
Radha Charan Verma, Gyanendra Prakash Sharma

Abstract Drying is a widely used method of food preservation. It leads to some structural changes in the dried material resulting in poor quality and rehydration. Freeze drying, though a costly process, reduces water activity without exposing the food material to high temperatures, eventually retains the original quality to a great deal. Moisture in the foods is frozen to ice which is sublimated under low pressure. Low pressure helps to vaporise the ice without transforming it to liquid, hence leaving the food structure porous in nature. The food is claimed to preserve the nutritional, sensory and re-constitutional qualities. 1.1 INTRODUCTION Most food materials are composed of a very high percentage of water, which can be as high as 95%, and this makes them susceptible to microbial activity. Microbial activity spoils the products, leaving them useless for human consumption. It not only changes their taste and color but it may also develop toxins, thus making them unsafe. There are various methods for preserving food but in order to make them shelf stable, removing water from foods helps keep them from spoiling for a longer period of time.

1 - 20 (20 Pages)
INR272.00 INR245.00 + Tax
 
2 Atmospheric Freeze Drying
Sadhana Sharma, Prabhat K. Nema, Siddhartha Singha

Abstract Drying is one of the most important industrial operations for preservation of food material. Due to the major limitations posed by convective drying methods, there is always a need for novel drying techniques which are technically, economically and environmentally sustainable. Based on the principle of moisture diffusion due to vapor pressure gradient, atmospheric freeze drying (AFD) offers a promising alternative to conventional drying systems. A cold gas with low water vapor pressure is used as drying medium to sublimate moisture directly from the frozen material at atmospheric pressure conditions. As a result the product gets dried at much lower temperature unlike convective drying. Thus, products dried with AFD retain better nutrition, texture and color and the process is also considerably cost effective. Major limitation of the AFD process is longer drying time, which can however be accelerated by using heat pump drying or new ultrasound technology. This chapter focuses on mechanism, benefits, limitations and comparative study of AFD with other drying methods such as hot air drying and vacuum freeze drying. It provides an insight regarding effect of AFD on properties of food material based on various studies reported in literature.

21 - 40 (20 Pages)
INR272.00 INR245.00 + Tax
 
3 Multi-Flash Drying to Produce Dried and Crisp Foods
João Borges Laurindo, B.A.M. Carciofi, R.L. Monteiro, J.V. Link

Abstract Multiflash drying (MFD) process is based on the application of multiple cycles of heatingvacuum pulse to a solid food. Heat can be provided by convection (from hot air), conduction (by contact with a hot surface), microwaves, or by a combination of these methods. Due to the moderate temperatures applied to the drying food, and the sudden decompression step (vacuum pulse), MFD processes allow obtaining crispyanddried foods with very good nutritional and sensory properties. Vacuum pulses cause food texturization, which depends on the pressure drop rate during decompression. In fact, the dried products are similar to freezedried foods, but with more open structures, which result in higher crispness. The dehydration can be performed in relatively short processing times, when compared with traditional drying processes (e.g. solar drying, airdrying, vacuum drying and freezedrying). The short process time indicates clearly that this class of drying process presents a huge potential to the production of driedandcrisp foods at industrial scale.

41 - 62 (22 Pages)
INR272.00 INR245.00 + Tax
 
4 Swell Drying
Sabah Mounir, Tamara Allaf, Karim Allaf

Abstract Airflow drying persists as the main dehydration operation. Indeed, the high expense of freeze-drying in term of equipment cost and energy consumption considerably restricts its use and confines its applications to high added value products (pharmaceutical products, cosmetics, etc.). However, airflow drying undergoes fundamental problems such as low operation performance, poor product quality and short reliability of the equipment. The time of drying is long; particularly at the end of the operation, which implies crucial energy consumption. The poor quality of the end product is related to thermal degradation and in particular to the compactness of texture as a result of the phenomena of shrinkage and case hardening. Another main problem common to all drying operations, including freeze-drying, is the safety of the end products. Swell-drying is defined as an operation that combines optimized hot air drying with instant controlled pressure controlled texturing. The improvement of texture, the preservation of sensory and nutritional quality, the possibility of manufacturing expanded granule powders and the reduction of drying time and energy consumption allow considering swell-drying as the most relevant drying process.

63 - 90 (28 Pages)
INR272.00 INR245.00 + Tax
 
5  Drying of Food Materials in Fluidized Beds
Andreas Bück, Evangelos Tsotsas

Abstract This chapter presents the principle of fluidisation and its use in drying of food materials. Being a convective drying process, capacity and kinetics are limited by process conditions and material properties. The influences are discussed as well as presenting the main equations that describe drying in fluidised beds. The main focus lies on hot gas drying, additionally superheated steam drying as well as atmospheric fluidised bed freeze drying and microwave-assisted fluidised bed drying are presented and discussed.

91 - 108 (18 Pages)
INR272.00 INR245.00 + Tax
 
6 Electrohydrodynamic Drying
Harjeet Singh Brar, Ashutosh Singh

Abstract Increasing global demand for ‘fresh-like’ processed food products has forced food industries to investigate into various minimal processing techniques. Food processing in general has been associated with thermal processing, alone or in various combination with chemical and mechanical preservation and processing methods. However, thermal processing methods are energy intensive in nature and tend to reduce product quality and freshness at the cost of shelf-life gain. Advance technique such as microwave, radio-frequency and freeze drying do maintain the product quality but their implementation at industrial scale involves high operational and maintenance cost. An ideal processing method therefore would be one that can process food products without losing its quality, is energy efficient and is easily scalable. In this chapter, we discuss about ‘Electrohydrodynamic (EHD) Drying’, which is can be classified as a minimal processing technique. The heat and mass transfer principles involved in EHD drying have been extensively discussed and so has been the key consideration for designing an EHD drying system.

109 - 128 (20 Pages)
INR272.00 INR245.00 + Tax
 
7 Pulse Combustion Drying
Wu Zhonghua

Abstract Pulse combustors provide an advantageous superposition of unsteady gas flow and high intensity sound waves. Such a combination does not only accelerate drying rates because of increased heat and mass transfer but also allows processing of liquids, pastes and agglomerated solids in a dispersed state due to aerodynamic impact from the high intensity sound wave. Over last decades, applications of pulse combustion in drying have been exploited continuously and different pulse combustion dryers have been designed and fabricated. In pilot tests and technical reports on these dryers, short drying time, high energy efficiency and product quality are generally reported, which cause that pulse combustion drying is regarded as a technology of the future in convective drying. This chapter attempt to introduce basic knowledge and state-of the art about this emerging technology and summarizes some recent studies in pulse combustion drying and equipment design. Following a concise description of pulse combustion and pulse combustor, the basic types of pulse-combustion dryers are presented, including spray dryers, fluidized bed dryers, impinging dryers, and dryers of special design. The existing commercial applications and pilot test projects are described and potential applications are identified.

129 - 162 (34 Pages)
INR272.00 INR245.00 + Tax
 
8 Foam Mat Drying
Sabah Mounir

Abstract Foam Mat Drying (FMD) is an economical alternative to drum, spray and freeze-drying for the production of food powders. The raw material is converted into stable foam by adding foaming agent through beating or whipping in presence or not of foam stabilizers, and dehydrated by different classical airflow and thermal means. A high-quality food powder attributes can be obtained by the proper selection of foaming method, foaming agents, foam stabilizers, time taken for foaming, suitable drying method and temperature. FMD can be used for large production of food powders because of its suitability for all types of food materials, rapid drying at lower temperature, retention of nutritive value and bioactive compounds, good reconstitution characteristics and flowability and cost-effective for producing powders. In this chapter, basics of foam and its structure, mechanisms of foaming, types of foaming agents and stabilizers for the production of stable foam have been discussed. The influence of foaming agents, foaming properties, thickness of foam and drying temperature on the drying characteristics of mat are also studied. This chapter analyzes the application of foam drying process for different food materials, the microstructure and whole quality attributes of obtained powder, and the energy consumption and costs of FMD as well.

163 - 186 (24 Pages)
INR272.00 INR245.00 + Tax
 
9 Ultrasound Application in Food Drying
Deepti Dashora, Prabhat K. Nema

Abstract Application of ultrasound is one of the most promising uses of novel technologies in food processing. Use of ultrasound at various stages of drying has resulted in significant decrease in drying time and improvement in quality characteristics of dried products. The chapter discusses the principle behind use of ultrasound, general application in food industry with detailed description of various drying processes and equipments assisted by ultrasound.

187 - 228 (42 Pages)
INR272.00 INR245.00 + Tax
 
10 Drying and Roasting of Cocoa and Coffee Beans
Ching Lik Hii, Abhay S. Menon, Choon Lai Chiang

Abstract Cocoa and coffee are highly sought after commodity crops in the market owing to the distinct flavor and aroma characteristics. Cocoa beans are mostly used in the manufacturing of chocolates and various types of confectioneries while coffee is mainly consumed in the form of beverages. Both cocoa and coffee need to be dried and roasted in order to produce the flavor precursors which further develop into the desired flavor and aroma in the finished products. This chapter aims to provide an overview of cocoa and coffee processing with particular emphasis on drying and roasting aspects and its impact on product quality.

229 - 240 (12 Pages)
INR272.00 INR245.00 + Tax
 
11  Processing and Drying of Mushrooms
Anjaly Shanker M., Sunil Pareek, Prabhat K. Nema

Abstract Mushrooms are the fruiting bodies of fungi, a group of organism that is different from fruits and vegetables. They are a rich source of good quality protein having more essential amino acids and vitamins with low calories. There are about six commonly known edible mushrooms throughout the world with button mushroom (Agaricus bisporous) being the most familiar and commercially important variety. Mushroom is a highly perishable product with a shelf life limiting to a few days. Soon after harvest, it starts to undergo physiological disorders like shriveling, wilting, liquefaction, browning, textural as well as weight losses and flavour changes. The main responsible factors for the quality deterioration after harvest are respiration rate, browning, bacterial spoilage of mushrooms, temperature and relative humidity. Because of its limited shelf life under ambient conditions of temperature and humidity, the preservation of mushrooms is a matter of concern. Various techniques have been involved in the extension of shelf life of mushrooms including chemical treatments, cooling, modified and controlled atmospheric storage, radiation, drying etc. Drying is one of the most accepted and effective methods for the long term storage of mushrooms. Mushrooms preserved by drying have a pleasant flavour and are used as an important ingredient in several food formulations including salads, instant soups, meats and rice dishes. Various drying processes like sun drying, hot air drying, freeze drying, vacuum drying etc. can be used for the long term storage of mushrooms. As mushrooms are sensitive to temperature, determining the right drying method is the key for the successful and effective operation of the system. The different operating conditions involved in various methods of drying affect product quality considerably. The effect of drying methods on the process and the quality of the dried mushroom is explained in detail in this chapter.

241 - 268 (28 Pages)
INR272.00 INR245.00 + Tax
 
12  The Degradation Mechanism and Kinetics of Vitamin C in Fruits and Vegetables during Thermal Processing
Jun Wang, Chung-Lim Law, Arun S. Mujumdar, Hong-Wei Xiao

Abstract Vitamin C is one of the most important phytochemicals and can be found in almost all fruits and vegetables. Since it covers almost all eventualities, being water solute and prone to leaching from cells, thermally labile (one of the most labile vitamins), pH-, metal ion-, light-sensitive, as well as readily oxidizable by ascorbic acid oxidase, vitamin C is selected as the most frequently measured nutrient to evaluate the nutrients loss during thermal processing. It is generally accepted that if vitamin C is well preserved, the other nutrients are also well retained. Higher retention of vitamin C in processed products is highly desired. Herein this chapter reviews the degradation mechanism and kinetics of vitamin C of fruits and vegetables during thermal processing, such as blanching, drying, cooking and frying. It starts with an overview of the functions of vitamin C in human’s health. Then the current status for understanding of the degradation kinetics of vitamin C during thermal processing was outlined, followed by the discussion of its degradation mechanism. At last, potential strategies or alternatives to keep vitamin C are identified and discussed.

269 - 296 (28 Pages)
INR272.00 INR245.00 + Tax
 
13 Energy Calculations for Dryers
Panagiotis A. Michailidis, Magdalini K. Krokida

Abstract Design, operation and optimization of dryers demands the calculation of energy consumption, in most cases in the form of thermal energy, equipment sizing, temperature and moisture distribution of solids as well as temperature and humidity distribution of drying air. Energy calculations are very important as drying is a widespread process in a variety of industries and is highly energy demanding. In the energy analysis of the process the first step is the estimation of the minimum energy requirement followed by the estimation of energy rejection through solids stream and especially through drying air. Increase of thermal efficiency is always willing and the two most common ways for its achievement is the application of heat exchange between cold feeding air and relatively hot rejecting drying air and hot air recirculation. The later is also employed for the adjustment of air temperature and humidity gradient through the dryer. The combination of a heat pump with the dryer decreases considerably the thermal energy consumption but demands electricity and the method can be beneficial in cases of excess electricity production in the process plant, e.g. by cogeneration. Utilization of exhaust hot air from the main drying unit for the predrying of wet solids can also decrease the total energy requirement. The application of humidity adsorption from the feed air increases its drying potential, but regeneration of adsorbent is required. Grand composite curve of the process plant can reveal potential heat sources from different unit operations.

297 - 346 (50 Pages)
INR272.00 INR245.00 + Tax
 
14 Modeling of Drying for the Recovery of Bioactive Compounds
Junior Franck Ekorong, Akouan Anta, Robert Ndjouenkeu, K.S.M.S. Raghavarao

Abstract The increasing interest in polyphenolic compounds in industries has led to the exploration and exploitation of rich bio-compounds from natural sources, essentially plants and their by-products. Solid-liquid extraction is mostly applied for the recovery of these valuable compounds from plants. Since the extraction process is often difficult in a fresh matrix, a drying operation is needed to reduce the moisture content, and preserve the targeted valuable compounds. An uncontrolled drying operation will lead to product damage and hence, loss in quality, reason why, several studies have been carried out to understand and control the drying process. The present chapter aims to present some data on drying for bioactive compound recovery from plants and their by-products, mainly polyphenolic compounds. Our main interest is the mathematical tools used to model the drying process.

347 - 362 (16 Pages)
INR272.00 INR245.00 + Tax
 
9cjbsk

Browse Subject

Payment Methods