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The dairy processing sector is a rapidly growing industrial segment across the globe. To keep pace with this development, academic institutions are increasingly compelled to introduce disciplines related to Dairy and Food Science/Technology. In order to meet industrial demands, it is essential to regularly update curricula and research activities. This book is primarily intended to support fresh graduates and postgraduates in the Dairy and Food Science/Technology fields. It aims to provide a solid foundation in theoretical concepts, thereby preparing students to effectively carry out laboratory experiments using various analytical techniques. I am deeply grateful to all my well-wishers whose encouragement motivated me to undertake this endeavor. I extend my sincere thanks to my family members for their unwavering support and cooperation throughout the preparation of this book. I would also like to express my heartfelt appreciation to Ms. Ankita Pandit and Mr. Aniruddha Mukherjee for their kind support during the writing process. Finally, I am thankful to the team at NIPA for their dedicated efforts in publishing this book in the interest of students. I warmly welcome suggestions from readers for any future improvements to this work.

1.1 Introduction Concentrated milks, like evaporated milk and sweetened condensed milk, serve as practical substitutes for fresh milk in regions where access to it is limited or where transportation and storage are challenging. These products go through specific processing techniques to reduce their water content, thereby improving their shelf life and transportability. Evaporated milk is created by removing water through evaporation and then sterilizing it to prevent microbial growth. This process results in a thicker consistency and a slightly caramelized flavor due to the heat treatment. On the other hand, sweetened condensed milk is made by adding a significant amount of sucrose to the milk and excluding oxygen, which inhibits microbial growth. This results in a thick, sweet product suitable for various culinary uses. These concentrated milk products are usually packaged in small cans, making them convenient for storage and transportation. However, they are sometimes diluted before consumption with water to resemble the taste and consistency of fresh milk. In regions where even concentrated milks are not easily accessible, alternatives like whole milk powder or recombined milk are used. These alternatives involve dehydrating milk into powder form or reconstituting milk components to create a liquid similar to fresh milk. Innovations in processing and packaging have led to the development of alternative uses for concentrated milks, expanding their versatility beyond traditional applications. These products continue to provide essential dairy nutrition in areas where fresh milk is scarce or hard to obtain, offering a shelfstable solution to meet dietary needs.

2.1 Introduction The continuous production of dry milk has become consistently significant within the dairy industry and is expected to continue growing due to its advantageous features. These include improved shelf life, reduced storage requirements, and lower transportation costs, all of which contribute to favourable economic outcomes. For example, non-fat dry milk is also known as skim milk powder, dried skim milk, non-fat dry milk solids, or dehydrated skim milk. Similarly, products like dried whole milk, dried cream, and dried buttermilk are often regarded as dried or powdered whole milk, cream, and buttermilk, respectively, based on their specific compositions. 2.2 Types of Dried Powder 1. Nonfat dry milk 2. Dry whole milk 3. Dry buttermilk 4. Dry whey 5. Dry ice cream mix 6. Dry creams (sweet or sour) 7. Dry skim milk vegetable fat products 8. Malted milk Powder 9. Cheese powders (Cheddar, Blue, etc.) 10. Sweetened chocolate flavoured non fat dry milk 11. Coffee creaming products 12. Sodium or Calcium Caseinates 13. Dry high acid milks 14. Partly skim milk powder 15. Infant milk food

3.1 Malted Milk Malted milk, originating from the ideas of British pharmacist James Horlick in the 19th century, was initially marketed under the name “Diastoid” before being trademarked as “malted milk” in 1887. Although initially targeted for infants and invalids, its appeal expanded due to its nutritional value, convenience, digestibility, and palatability. Recognized globally for its lightweight, non-perishable nature, and high-calorie content, malted milk is created by evaporating a mixture of malted barley, wheat flour, and whole milk until it forms a powder. There aremainly two types of malt powder: diastatic and non-diastatic. Diastatic malt containing enzymes breaking down starch into sugar, aiding in dough rise and crust formation, particularly in bread making. Non-diastatic malt lacks active enzymes and is primarily utilized for flavor enhancement, commonly in beverages. It may also include sugar, coloring agents, and other additives to improve taste and appearance. 3.2 Malting Malting is a crucial process employed in treating cereal grains, such as barley, by inducing germination through soaking in water followed by halting the process through drying or heating with hot air. This technique encompasses two main stages: sprouting and kiln-drying. The term “malt” encompasses several products of this process: 1. Malted grains: These are grains, like barley, that have undergone the malting process. 2. Malt sugars: These are sugars, predominantly maltose-rich, derived from malted grains, often utilized in baking, such as baker’s malt. 3. Malted milk products: These include beverages like malted milkshakes, made using malted milk.

4.1 Introduction Human milk widely acknowledged as the optimal source of nutrition for infants, providing a rich array of components crucial for their growth, repair and development. However, the composition of human milk can vary significantly within and between feeds, throughout the day, over the course of lactation, and among different mothers and also populations. While this variability is beneficial for infant health and survival, it presents challenges for the management of nutrition of high-risk infants who require precise oversight. The composition of human milk can be altered by factors such as the handling of expressed milk, including how it is stored and pasteurized. Thus, proper management of expressed milk is essential. The recommended practice for infant nutrition is exclusive breastfeeding for the first six months, followed by continued breastfeeding for at least one to two years. Human milk is naturally suited to meet the nutritional needs of infants, providing both nourishment and bioactive compounds that support healthy growth and immunity. Human milk contains a variety of bioactive components, such as immune cells, anti-infective and anti-inflammatory agents, growth factors, and prebiotics. In contrast to infant formula, which has a fixed nutritional profile, human milk is dynamic and can vary between and within feedings, influenced by maternal factors, environmental conditions, and the methods used for expressing and managing milk. A thorough understanding of human milk’s composition is vital for effective infant feeding, especially for at-risk infants. It also allows for the assessment of how milk storage and pasteurization may impact its beneficial components. Additionally, some of the bioactive elements in human milk are being studied for their potential use in medical treatments, either as preventive or therapeutic agents.

Experiment No.- 1 AIM To determine the sucrose content in condensed or evaporated milk using the Lane-Eynon method. Principle The Lane-Eynon method is used to measure sucrose in condensed milk by utilizing the reducing properties of sugars. Sucrose, being a non-reducing sugar, is first hydrolyzed into glucose and fructose (reducing sugars). These reducing sugars then react with Fehling’s solution, producing a brick-red precipitate of cuprous oxide (Cu2O) when heated. This allows for the accurate determination of sucrose content after the hydrolysis (inversion) process. Reactions • Reaction of Fehling’s Solution • CuSO4 + NaOH → Cu(OH)2 + Na2SO4 • Cu(OH)2 + Reducing Sugar (RCHO) → Cu2O (brick-red precipitate) + RCOOH This reaction forms cuprous oxide (Cu2O), a brick-red precipitate. The intensity of this precipitate correlates with the concentration of reducing sugar in the sample, providing a way to determine sucrose content.