eChapters

3.1 Introduction

The subject of heat transfer is firmly grounded in the sciences of thermodynamics and fluid mechanics. It has become exceedingly important for engineers to possess a clear understanding of the principles of heat transfer and its application to a large number of problems. In view of process engineering, the knowledge of heat transfer and its application is most important, because heat transfer is one of the basic unit operations in the agricultural processing activities. The design of process equipments, refrigerators, boilers or type of heat exchangers, thermal treatment of food grains, cooling of perishables, pasteurizations, sterilizations, freezing of milk and fruit juices and a large number of similar applications involve consideration of heat transfer rates. There may be other situations where heat is being generated during a certain operation, and may be detrimental to the equipment and the food product. In such cases we are often faced with the task of removing the undesirable amount of heat as far as possible.

1. Herbs and Spices
       
    1.    International Standards Organization (ISO) defines spices and condiments as: Vegetable products or mixtures thereof, free from extraneous matter, used for flavouring, seasoning and imparting aroma in foods.

    2.    Rosengarten describes a spice as a product which enriches or alters the quality of a thing, for example altering the taste of a food to give it zest or pungency; a piquant or lasting flavouring; or a relish. The term ‘spice’ is thus used to cover the use of spices, herbs and certain aromatic vegetables to impart odour and flavour to foods.

    3.    Herbs may be defined as the dried leaves of aromatic plants used to impart flavour and odour to foods with, sometimes, the addition of colour. The leaves are commonly traded separately from the plant stems and leaf stalks.

High Humidity Hot Air Impingement Blanching (HHAIB) is a modern blanching technology developed to overcome several limitations associated with conventional blanching. This chapter introduces HHAIB as a pretreatment used before drying, freezing, canning and frying, particularly for fruits and vegetables. It explains the underlying principle of high-humidity hot-air impingement and its effects on heat and mass transfer. The chapter discusses applications in pre-dehydration treatment, colour preservation, texture and structural integrity and enzyme inactivation. Comparative analysis with conventional blanching methods highlights its potential advantages in drying efficiency, quality retention and energy utilization, making HHAIB an important emerging technology for modern food processing.

1. Introduction

Fruit products have their unique identities having large content of micronutrients, polyphenols, vitamins, flavonoids and other nutritional compounds. Characteristic appearance and flavors distinguish among various fruit based products like juice, puree, jam, jelly, squash and other several varieties. Main concern of this fruit processing industry is the stability of the products throughout the post processing storage. Thermal treatment as mean of preservation of these products is the common process implemented so far. It ensures the safety of the product but lacks in retaining the nutritional intact that like of fresh fruit. Today’s consumer demand for minimally processed fruit products and “natural” fruit products tend to think of alternative thermal processing.

High pressure processing (HPP), a relatively new concept compared to conventional thermal processing, also sometimes known as high hydrostatic pressure (HHP), or ultra high pressure (UHP) processing, is a non-thermal food processing method that subjects liquid or solid foods, with or without packaging, to pressures ranging between 50 and 1000 MPa. HPP has already been established itself as an alternative to thermal processing. In food processing it is of great interest due to its ability to inactivate food borne microorganisms and enzymes, at low temperature, without the need for chemical preservatives and it is less detrimental than thermal processes to low molecular weight food compounds such as flavoring agents, pigments, vitamins, etc., as covalent bonds are not affected by pressure. Pressure-treated foods have sensory properties similar to fresh products, which is a major advantage in fruit processing as it matches consumer demand for healthy, nutritious and ‘‘natural’’ products. HPP of fruit products offers the chance of producing food of high quality, greater safety and increased shelf life (Hayashi 1989; Gould 1996; Butz and Tauscher 1998).

Food and nutrition are necessary for all living beings to maintain good health[1]. Thermal treatment is commonly used for preservation of food. Although application of thermal treatment can ensure food safety, it may cause undesirable changes in the nutritional, sensory and functional properties of food products[2]. Due to growing awareness of connection between the diet and the health, there is an increase in demands for fresh-like, palatable, additive-free and microbiologically safe food products with high nutritional value and quality[3].

Ice cream has evolved from simple frozen preparations into a sophisticated food industry combining dairy science, food chemistry, refrigeration, microbiology, processing technology, packaging, and cold-chain management. This chapter introduces the historical development of ice cream and explains its transformation from a luxury product into a widely consumed frozen food. It examines the characteristics of the industry, major categories of ice cream and related frozen products, flavour classifications, composition, and quality characteristics. The chapter also presents the basic manufacturing process, important quality-control parameters, common manufacturing challenges, and emerging industry trends, providing a foundation for understanding ice cream as both a technical product and a commercial business.

Microorganisms (or microbes) are organisms too small to be seen with the naked eye. The science of microbiology is the study of microorganisms, their properties, classification, growth requirements, method of reproduction and distribution in nature. These organisms range in size from tiny viruses to larger bacteria, protozoa, algae, fungi and some of the microscopic worms (helminthes). They are present everywhere in our environment, in our homes, on our bodies, on the things we touch and on the food we eat. They are important for human survival on Earth, playing an essential role in many processes that maintain life. In nature, microorganisms carry out a number of important functions.

1.They are responsible for the decomposition of organic matter.

2.Recycling of nutrients that help to maintain the balance of chemicals in the soil.

3.Special nitrogen-fixing bacteria live symbiotically with certain plants, absorbing nitrogen from the air and converting it into compounds which can be used by the plant for growth.

4.Some algae are capable of photosynthesis, using energy from the sun to convert carbon dioxide in air into carbohydrate.

5.Marine microorganisms form the basis of the food chain in lakes, rivers and oceans.

6.Certain microorganisms are used in the manufacture of food.

7.Pharmaceuticals and drugs.

8.Industrial processes.

9.A valuable tool for scientific research.

10.Use in laboratory experiments to understanding metabolic pathways and in the discovery of the genetic code.

11.1 Introduction
“Homogenization” is the method of mechanical treatment producing a stable emulsion of milk fat and milk serum. Homogenizer is the name given to the equipment employed for this aim. The fat globules in milk range in size from 1 to 20 microns; the average is 4 to 6 microns. The homogenizer reduces the size of the fat globules in milk or cream passing through it. The most of them are less than two microns. After homogenization, no cream line develops on milk; churning homogenized cream cannot generate butter grains. Moreover, milk like cream’s viscosity is changing, which increases the resistance the smaller fat globules face. The increase in viscosity is ascribed to the fact that more milk protein will be deposited on the surfaces of more fat lobules. Homogenizing milk changes its clotting characteristics, so the curd made with rennet or pepsin is supposed to be softer. Because lipolytic enzymes adsorbed on the extra surfaces provided by the more numerous tiny fat globules hydroly fat, homogenized milk or cream may become rancid more quickly than untreated goods. The milk or cream must be pasteurized either right before or right after homogenization to prevent these changes. Usually, the milk is homogenized after main heating and then pasteurized. Driven via a small valve against hard surfaces, heated milk is under pressure of 2500 psi and in a second stage under 500 psi. With a 1/10000 inch diameter, the aperture the liquid is driven through is quite small. Mechanical force milk through a narrow passage at high speed produces homogenized milk. This produces a stabile fat emulsion and breaks down the fat globules in milk into considerably smaller ones. Homogenization reduces the inclination of the fat globules to cluster and merge into cream. Milk is an emulsion whereby fat globules are distributed across a constant skim milk phase. Raw milk left to sit will finally cause the fat to climb to the top and form a cream layer. By means of a small opening under high pressure, homogenization mechanically breaks down the fat globules. While increasing their number and surface area, this lowers the average size of the fat globules. Practically speaking, the net effect is a substantially decreased inclination for creaming of fat globules. Three elements contribute to this increased stability of homogenized milk: a decrease in the mean diameter of the fat globules (a factor in Stokes Law), a decrease in the size distribution of the fat globules (causing the speed of rise to be similar for most globules such that they do not tend to cluster during creaming), and an increase in density of the globules (bring them closer to the continuous phase) owing to the adsorption of a protein membrane. < Heat pasteurization also breaks down the cryo-globulin complex, which often clusters fat globules causing them to increase. The homogenizer consists of a high-pressure pump with an adjustable opening based on a minute orifice. High pressure force of fluids through the orifice causes a notable change in the physical characteristics of the treated product and generates a very intimate combination of the fluid components. Annexure- II has a Homogenizer schematic.

1. Introduction

Raw milk is an emulsion. It is a mixture of milkfat globules, Solid Not Fat (SNF) and water. Over time, milkfat globule separate out from milk serum and comes to the surface of milk as a layer of cream due to the low density of milkfat or due to heating of milk. When milk is heated rapidly and continuously, some of the water in it evaporates from the surface. This exposes proteins and fat molecules, which bind and dry out and forms a skin like film on the surface. 

13.1 Introduction

Hospitality industry is the second largest industry in the world. It is well diversified and can be chosen as per the interest. Hospitality management involves planning, organizing, directing and controlling human and other resources within the different segments of hospitality industry i.e. lodging, restaurant, travel and tourism, institutional management, recreational management, meeting and convention planning industries. Although, these all are separate but related segments of the hospitality industry and are interrelated to provide good and efficient services to the guests and users. Hospitality industry provides services which are need oriented and differ in various parts of the world as per regions and the traditional styles.

The first building created specifically for hotel was ‘City Hotel’ with 73 rooms at 115 Broadway, New York in 1794. Pallonjee Pestonjee established the very first western-style hotel in India, “The Bristol Hotel” in Mumbai in 1840. According to the report of the department of Tourism, Government of India, at the end of the year 2004, there were 167 Five star hotels with approx. 28,900 rooms, whereas 126 Four star hotels, with 8,831 rooms [2]. To expedite the ongoing process of classification/re-classification of functioning hotels in one to three star categories, five Regional Committees have also been set up in Delhi, Mumbai, Kolkata, Guwahati and Chennai to conduct inspection [3].

According to Futter (2001) it is very important the way we cook our food. If the cooking is inadequate it causes food poisoning. While cooking there can be cross contamination starting from raw foods. It includes hands or utensils which can cause food poisoning. Most foods, especially meat, poultry, fish and eggs should be cooked thoroughly to kill most types of food poisoning bacteria. Generally the food should be cooked to a temperature of 75 °C or hotter. When food is cooked, it should be eaten promptly, kept hotter than 60 °C or cooled, covered and stored in the fridge or freezer. Some people are more at risk from food poisoning than others. In order to buy safe food in the market like buying pre-cut produce as a half a watermelon or cut veggies from a salad bar, it is important to choose items that are refrigerated or surrounded by ice. They must be kept in separate bags. FDA (2019) has studied the contamination in lettuce. Shopping at a farmer’s market is a great way to get locally-grown, fresh fruit, vegetables, and other foods. However, safety of these produce needs to be checked. Many markets have their own food safety rules and vendors must comply with them along with the government regulations. Fruits and vegetables must be washed thoroughly under running water just before eating, cutting or cooking. Fruits and vegetables must never be washed with soap or detergent or using commercial produce washes. Even if it has to be peeled before eating, it is still important to wash it first. Any bacteria present on the outside of items like melons can be transferred to the inside when it is cut or peeled. They should be refrigerated within two hours after preparation. The juice or cider must be treated (pasteurized) to kill harmful bacteria. Pregnant women, children, older adults and people with weak immune systems should drink only pasteurized or treated juice. Raw milk can harbor dangerous microorganisms like Salmonella, E. coli, and Listeria. World India (2017) has looked into the food regulations. These can pose serious health risks. Pregnant women, older adults and people with weakened immune systems are at higher risk for illness caused by Listeria. One source for these bacteria is soft cheese made from unpasteurized milk. It is vital to check the label to make sure that it is made from pasteurized or treated milk. Make sure that eggs are properly chilled at the market. FDA requires that untreated shell eggs must be stored and displayed at 45°F. While buying eggs it needs to be ensured that the eggs are clean and the shells are not cracked. Meat should be properly chilled even in the market and kept in closed coolers with adequate amounts of ice to maintain cool temperatures. If it is brought in an insulated bag or cooler during transit it is very beneficial to keep the quality. It should be always kept separately from your other purchases, so that the juices from raw meat (which may contain harmful bacteria) do not come in contact with produce and other foods. Essays (2018) have written a very comprehensive overview of food safety.

Today, organic and local foods are preferred as they use less pesticides or fertilizers. However, these foods, like others, can be exposed to harmful bacteria during the growing and harvesting process. The farmers and distributors must use good sanitary practices to minimize food contamination. Consumers should cook food properly. The street food vendors are a traditional and indigenous fast food approaching in most countries of the South-East Asia Region. As these are economical they cater to millions of consumers. Among safe street foods there are many contributing factors that are associated with the safety of street food. WHO had conducted a survey in 1993 covering 100 street foods in 100 countries around the world. It revealed that the major health threat comes from raw and undercooked food, infected food handlers and inadequate hygiene practices in processing and storing such food. If the street food is cooked well and is served hot, then the chances of food poisoning is less. The water quality, hygienic conditions and the level of cleanliness especially in the summer season are the major factors for food poisoning. However improvements in physical infrastructure and hygienic conditions are growing as consumers are also demanding quality food. Michael et al., (2017) have looked into organic versus conventional foods.

INTRODUCTION

The concept of hurdle technology has been developed as a new way to realize safe, stable, nutritious and economical foods. It employs combination of different preservation techniques to achieve a multi-target, mild but reliable preservation of foods. The application of hurdle technology in food preservation is increasing rapidly worldwide. Over the years, insight into the hurdle effect has been broadened and the application of hurdle technology has been extended. A better understanding of the occurrence and interaction of food preservative factors (hurdles) in foods is the basis for improvements in food preservation. If the hurdles for the microbes are known, the microbiological stability and safety of this food might be optimized by changing the intensity or quality of these hurdles. Using the proper combination of hurdles, it is possible to improve not only the microbial stability and safety but also the sensory and nutritive quality as well as the economical aspects of food. The hurdle concept is also referred to as food preservation by combined methods, combined process, combination preservation or combination processing techniques. The hurdle effect is of fundamental importance for the preservation of foods. The illustration of hurdle effect was first introduced by Leistner in 1978. Based on the understanding of hurdle effects, the concept of hurdle technology was derived (Leistner 1985).

Safe, wholesome and nutritious food is vital for sustenance, good health, food and nutritional security and augmentation of sustainable development of an individual. Also, safe food helps in the growth of the national economy and enhances the trade and tourism sector. Foods that are unsafe containing various kinds of microorganisms can cause chronic diseases or illnesses varying from diarrhea to cancer.

Dairy equipment and utensils with which milk and milk products come into contact are the main sources of contamination in the products. By the use of effective equipment cleaning and sterilization methods on routine basis, milk of high bacteriological quality can be consistently produced. In composite milk plant, a variety of equipment and utensils are used. The use of stainless steel for the fabrication of dairy utensils and equipment provide highly polished and hard smooth surface that can be cleaned readily, apart from showing resistance to corrosive action of detergents and bactericidal solutions. Utmost care is taken to avoid dents and scratches, which could be the possible focal points of subsequent contamination. To overcome all these problems aluminium and stainless steel vessels and equipment present an ideal situation.

Abstracts

To ensure safe food and adequate sanitation programs, the equipment used for processing of food products must be designed, fabricated, constructed, and installed according to sound hygienic design principles. This ensures the equipment can be adequately cleaned and sanitized, and that surfaces are resistant to daily exposure to corrosive food products and cleaning/sanitizing chemicals. This chapter focuses primarily on fundamental principles of hygienic design, which protect the product from microbial, chemical, and foreign-body contamination. This is followed by a discussion of general aspects of hygienic construction and design of food equipments, the selection of materials of construction and specification of surface finishes, fabrication, installation and cleaning and sanitization. Quality of raw materials or foods ingredients, proper processing, packaging and storage of finished products decides the quality of the food products. Planning for plant and equipment layout, its design, services (water, air, refrigeration, steam), waste disposal etc. are some of the critical factors, which contributes to quality. In addition, the food processing equipment must comply with strict standards and regulations, which are necessary for securing the quality and safety of the food products to the consumers.

The Concept of ‘Clean Milk’ Production

Although milk is nature’s most ideal and perfect single food both for the newborn and the mature human beings, the possibility of it being a source of biological and chemical hazards cannot be excluded. In view of the immense dietary importance of milk, the need for production of safe, clean and wholesome milk is emphasized. The term ‘clean milk’ does not mean milk in which all visible dirt is absent or milk from which it has been removed; rather it does denote raw milk from healthy animals, that has been produced and handled under hygienic conditions; that contains only small number of harmless bacteria and that possesses a good keeping quality without being treated by heat. In other words, the unhygienic production of milk may lead to inferior keeping quality as a result of rapid microbial multiplication under favourable storage conditions apart from serving as a potential health hazard. These microorganisms cause the milk to sour quickly, putrefy and develop undesirable flavours, colour defects, ropiness and bitterness. On the other hand, the pathogenic microorganisms, which may gain entry through various sources, may cause many diseases to the consumers.

Ice cream over the years has come to acquire an easy acceptance as a healthy, nutritious and hygienic food for the aged, sick, growing children and adults. Its popularity, as demonstrated on all types of occasions is growing fast and its potential appears to be unlimited.

Gone are the days when the word “Ice Cream” was synonymous with strawberry and vanilla flavours or the innocuous orange. Ice cream is available in many forms, flavours and packages. Today, there are exotic variations to titilate the palate, such as Jingle Bells, Goody goody Gum Drops, Champagne Snowballs, Mr. Frost, Tutty Fruity, Butter Scotch, etc, waiting to launch customers on a gastronomical voyage.

It is uncertain how long ice cream has been produced, however, the International Association of Ice cream Manufacturers (1966) traces the beginnings of ice cream and frozen desserts to iced drinks enjoyed by Alexander the Great in the fourth century B.C. down through the years Nero in the first century A. D., Marco Polo in the 13^th century through Italy and France to England in 1643-1649, and to America around 1700. From a very old writings it has been learnt that the Chinese liked a frozen product made by mixing fruit juices with snow, what we now call water ice. It is believed that ice cream evolved from iced beverages and water ices that were popular in the medieval period. This technique later spread to ancient Greece and Rome, where the wealthy, were partial to frozen desserts.

After disappearing for several centuries, ice creams in various forms reappeared in Italy in the Middle Ages, most probably as a result of Marco Polo returning to Italy in 1295 after a 16-17 year stay in China, where he had learnt to appreciate a frozen dessert based on milk. There is no gainsaying the fact that the true origin of ice cream cannot be proclaimed with a fair measure of certainty but, all the same, the Italians claim that Benaroo Bountalenti, a resident of Tuscany, invented ice cream in the early 1300s. From Italy ice cream spread over Europe during the 17^th century, and for long remained a luxury product for the royal courts. Italian ice cream was very popular in London around 1870.

A greenfield ice cream project involves much more than installing production machinery. It requires integrated planning of the business model, market opportunity, capacity, product portfolio, plant layout, process technology, refrigeration, utilities, packaging, cold storage, quality systems, regulatory compliance, distribution, working capital, and future scalability. This chapter presents a practical framework for evaluating new ice cream manufacturing projects, with particular attention to a representative 1000 LPH facility. Different project scales and business models are considered along with major plant and machinery requirements. The chapter also highlights common project-planning mistakes and best practices. It helps entrepreneurs and investors assess technical feasibility, operational readiness, financial requirements, scalability, and long-term commercial viability.