eChapters

Abstract

Most dryers operate at low thermal efficiency. The development of models and control systems offers an opportunity to improve dryer operation and efficiency. Dryer control is very important and with deeper understanding of the drying concept, new “smart” dryers can be made more reliable and more cost-effective than classical dryers. This chapter will provide an overview of necessity of control and safety measure in food drying system, and terminology related with drying control system. Different control strategy includes conventional and advanced techniques implemented in drying operation are reviewed  here and simple outline of intelligence control system in drying technology are briefly described in succeeding section. Various hazards in drying process and risk and safety management will also be discussed.

Introduction
Antimicrobial resistance (AMR) poses an escalating threat to global health, eroding the efficacy of antibiotics and complicating the management of bacterial infections. The proliferation of resistant pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum betalactamase (ESBL)-producing Enterobacteriaceae, and multidrug-resistant Mycobacterium tuberculosis, has driven significant increases in morbidity, mortality, and healthcare costs. The ability to detect AMR accurately and promptly is paramount for guiding clinicians in selecting effective therapies, implementing targeted infection control measures, and informing public health strategies to curb the spread of resistant organisms. Conventional methods, rooted in phenotypic assessments, have served as the cornerstone of AMR detection in clinical microbiology laboratories for decades. These techniques evaluate bacterial growth under controlled exposure to antibiotics, offering direct evidence of resistance or susceptibility that molecular approaches, which focus on genetic markers, may miss due to silent mutations, complex regulatory mechanisms, or novel resistance pathways. This chapter provides an exhaustive examination of conventional AMR detection methods, encompassing disk diffusion, broth and agar dilution, gradient diffusion, and automated susceptibility testing systems. These approaches, refined through decades of clinical and research application, remain indispensable for their reliability, cost-effectiveness, and adaptability across diverse settings, from well-resourced tertiary hospitals to laboratories in low-income regions. By exploring their principles, procedures, applications, and limitations, we aim to underscore their enduring significance amidst the rise of rapid molecular diagnostics. The discussion also addresses specialized tests for detecting specific resistance mechanisms, such as beta-lactamase production, inducible clindamycin resistance, and carbapenem’s activity, which are critical for tailoring antimicrobial therapy. Through a critical lens, this chapter evaluates the strengths and challenges of these methods, offering insights into their role in addressing the global AMR crisis, their integration with emerging technologies, and their continued relevance in both routine diagnostics and epidemiological surveillance. The value of conventional methods lies in their ability to translate laboratory findings into actionable clinical decisions. Unlike genotypic methods, which detect resistance genes but may not predict phenotypic behaviour, these techniques assess how bacteria respond to antibiotics under conditions mimicking in vivo environments, aligning closely with therapeutic outcomes. As resistance patterns grow increasingly complex, driven by mechanisms like carbapenem’s and efflux pumps, conventional methods provide a practical foundation for diagnostics, particularly in resource-limited settings where advanced molecular tools are often inaccessible. Their role in global AMR surveillance, such as through the World Health Organization’s Global Antimicrobial Resistance Surveillance System (GLASS), further underscores their importance in tracking resistance trends and informing policy.

The Metric System

At present metric system is followed to calculate final results in analysis work. This system is quite simple in nature as well as in principle. The units of the metric system are: (1) the  metre (linear measure), (2) the litre (measure of capacity), and (3) the gram (measure of mass.)

One litre is the volume of pure water at 4ºC and 760 mm pressure which weigh 1 kilogram (kg). One litre equals 1000.027 cubic centimetres (Cm3) for most work, the units “millilitre”, “cubic centimetre” and used interchangeably.

At present there are three different temperature scales in common use. These are: the Fahrenheit (F), used chiefly in English-speaking countries. the centigrade (C), used universally in scientific work and the Absolute (T) or Kelvin (K) scale, differing from the centigrade only in the position of the zero point, its divisions being of the same size. its zero point is -273ºC. The kelvin scale is used especially in dealing with very high or very low temperature and in computations involving the laws of gases. The following formulae can be used for converting one scale to another:

Conversion of muscle to meat is a complex process in which several physical and chemical changes takes place over a period of several hours or even days. The major changes which take place during this process include fall in muscle pH and temperature as well as muscle shortening which further leads to proteolysis or ageing. These changes during conversion of muscles to meat are variable and have great effect on meat quality (tenderness, juiciness, flavour, colour etc.) and also on certain processing characteristics like emulsification, binding properties and yield of the products. To know this complex process it is necessary to understand the process of energy production and metabolic pathway shifting in live animals.

Pre Slaughter

In the living animal, aerobic metabolism is used to obtain energy. The source of energy at this stage is either free fatty acids or blood glucose or muscle glycogen. In this process total 38 ATP molecules are produced from single glucose or glycogen molecule by the complex processes known as glycolysis, oxidative decarboxylation and oxidative phosphorylation. However, under stressful situations, anaerobic metabolism may be used and lactic acid is produced. Lactic acid is usually transported from the muscles to the liver, where it is re-synthesized into glucose and glycogen, or to the heart, where it is metabolized to carbon dioxide and water.

Principle

The use of boric acid as an ammonia absorbent was first introduced by winkle  (1913-15). Conway and O’Malley (1942) used boric acid for ammonia absorption in their original micro diffusion technique.

The ammonia liberated in the outer chamber by alkali addition in the usual way is absorbed in boric acid mixture plus indicator in the central chamber (slightly reddish), the pH of this mixture being approximately 5 before absorption. During the ammonia absorption the pH of the mixture rises, and to upwards of 8.0 (the strength of the mixture being such as to prevent it rising further). After the required period, the fluid in the central chamber is titrated to a faint permanent reddish tint with standard acid. A mixture of methyl red and bromocresol green was found satisfactory  to work as an indicator to assist in titration job.

Definition

It is one of the important portion of milk which forms a fatty layer on top of milk when left un-disturbed. It is a prime component of milk and comprises mainly of milk fat. It may be defined as “that portion of milk which is rich in milk fat” meaning portion of milk into which larger portion of milk fat has been gathered.  According to FSSAI, 2011 Malai and Cream are defined as –

Malai means the product rich in butter fat prepared by boiling and cooling cow or buffalo milk or a combination thereof. It shall contain not less than 25.0 per cent milk fat.

Butter is one of the leading milk product in developed countries of the world. It serves as a balance wheel of dairy industry. Surplus milk is generally converted into butter to be used during the times of scarcity. It is an article of commerce and a sign if wealth. Butter is a fat concentrate, which is obtained by churning cream, gathering the fat into a compact mass and then working it for proper distribution of moisture and salt. The art of butter making has a long history. The manufacture of butter was confined to colder regions where gravity creaming was successful. The milk was allowed to stand undisturbed for 10-12 hours until layer of cream collects at the top.

Cultural characteristics of bacteria deal with the appearance of the growth in various liquid and on solid media. The growth characteristics of most of the bacteria are typical of the group or species and help in their identification. The terminology employed to describe various features of bacterial growth are mentioned below.

Culture methods employed depend on the purpose for which they are intended. In the laboratory the indications for culture are mainly to

1.Isolate bacteria in pure culture.

2.Demonstrate their properties

3.Obtain sufficient growth for preparation of antigens and for other tests.

4.Type isolates by methods such as bacteriophages and bacteriocin susceptibility.

5.Determine sensitivity to antibiotics

6.Estimate viable counts

7.Maintain stock solution

Introduction 
The discovery and introduction of antimicrobial agents to clinical medicine was one of the greatest medical triumphs of the 20th century that revolutionized the treatment of bacterial infections. However, the gradual emergence of populations of antimicrobial resistant pathogenic bacteria, resulting from use, misuse and abuse of antimicrobials has today become a major global health concern. Antibacterial drugs have revolutionized our ability to control bacterial disease, and their clinical availability has led to dramatic decreases in morbidity and mortality. (Walsh and Wright, 2005). As such, these therapeutics underpin modern medicine. Despite the integral role of antibiotics in sustaining our modern lifestyle, they are undervalued in both cost and significance by society. Over the past century, their use has provided strong selective pressure on microorganisms, leading to preferential survival and spread of those harbouring antibiotic resistance mechanisms. Multidrug resistance is now commonplace amongst bacterial pathogens with antibiotic resistance now affecting all antibiotic classes. (Coates et al, 2011). This is particularly worrisome in the case of Gram-negative bacteria (e.g. Pseudomonas aeruginosa and Acinetobacter baumannii) for which treatment options are already limited. The ‘broken’ economics of antibacterial research and development is often quoted as the main reason for the lack of new therapies but the truth is that it is hard to discover new antibacterial drugs, and the science is not sufficiently advanced to allow discovery of efficient and effective drugs. This has led to fears of a ‘post-antibiotic era’ as it has been estimated that 5–20 novel antibacterial drugs need to enter clinical development in order to effectively contend with the current resistance problem. However, given the attrition rate within the existing drug discovery model, at least 200 discovery programmes would be needed in order to achieve this outcome. Hence, new approaches to antibiotic discovery are needed. The antibiotic pipeline The antibiotic pipeline is not what it once was.4 Pharmaceutical companies were once the main provider of novel antibiotic molecules but they largely withdrew in the late 1990s because of the lack of success and low financial returns in bringing new antibacterial drugs to the market.5 The environment of discovering and developing new antibiotics was quite different during the so-called ‘golden era’ of drug discovery. Antibiotics worked remarkably well because resistance was low and physicians had access to a variety of efficacious antibiotics. Antibiotic research and development programmes were inclined to focus on improved pharmacology to achieve less frequent dosing e.g. once a day, rather than innovative new antibiotics. Natural product screening strategies tended to result in rediscovery of compounds rather than finding new ones. There was also no need to consider those natural products with undesirable properties such as toxicity. Today, only a few large companies such as GlaxoSmithKline, Novartis, Merck and Roche are still actively engaged in antibiotic R&D, with many of the original antibiotic provide.The natural world remains the largest source of novel drug scaffolds making this a viable option in the search for new antibiotic compounds. Advances in bacterial culture techniques, molecular biology and metagenomics will make natural product drug discovery easier and more costeffective, obviating these limiting factors. Screening procedures must include whole-bacterial cell assays, addressing the issue of bacterial permeability and efflux early in the discovery process (Shore and Coukell, 2016). Additionally, the generation of training schemes by, and with, pharmaceutical companies that cover all aspects of the pipeline and include natural product drug discovery, are essential and will ensure that expertise is passed on to future researchers. Investment should also be made into the study of previously characterized lead compounds that did not reach the clinic, so called old leads. The reasons that led to these compounds being dropped from further development vary, ranging from financial issues to trial design, dosing problems and toxicity. It may be that there is now sufficiently improved technology and expertise to develop these as safe and efficacious antibacterials. The revival of interest in old leads could also provide an additional source of novel antimicrobials. A freely accessible database of antibiotics that were never developed has recently been launched, Antibiotic with the aim to reduce unnecessary duplication of Pharmaceutical agents such as nanospheres, liposomes, and immunoglobulins for example have been developed which can alter the pharmacodynamics of a compound, act as carriers for sustained or controlled drug release, and for immunization therapy.

Introduction

Today, antimicrobial resistance (AMR) has become a global issue, contributing to rise in mortality and cost of treatment. Antimicrobial resistance (AMR) is the resistance of a microorganism against an antimicrobial agent to which it was originally sensitive (WHO, 2013). Dispersion of antibiotics is done at large scale, in India even sometimes without any proper prescription. Animal Husbandry is not untouched and antibiotics are used to a great extent, which needs enforcement of strict government rules and regulations for their use in f ield conditions (PHFI, 2011).

Extended-spectrum β-lactamases (ESBLs) are enzymes that hydrolyse most of the β-lactam antibiotics and thus mediate resistance to penicillins, 3rd and 4th generation cephalosporins (Saravanan et al., 2018). Beta-lactamase inhibitors, inhibit these ESBLs such as clavulanic acid, sulbactam and tazobactam (Trott, 2013). The genes encoding for these enzymes are commonly found both on the chromosomes and plasmids among Enterobacteriaceae family (Kotsoana et al., 2019).

Among Enterobacteriacae, E. coli and Klebsiella species are main environmental pathogens associated with various illnesses such as acute bovine mastitis (Koovapra, 2015), pathogenic E. coli with diarrhoea and extra intestinal infections in humans and animals (Levine et al., 1987), K. pneumoniae with respiratory and urinary tract as well as bloodstream infections (Daehre et al., 2018). Resistance to extended-spectrum β-lactams occurs mainly in members of Enterobacteriaceae family through plasmids encoded ESBL genes. (Sharma et al., 2010).

Meat cutting and fabrication is a skilled process in which separation of carcass into wholesale primal cuts is done to facilitate meat trade requirements, consumer preference and easy handling to the butchers. The person engaged in cutting and fabrication of carcass cuts must be skilled and expert in their job. He/she must have the expert knowledge of carcass configurations and location of retail cuts in animal carcasses. To obtain good quality retail cuts, carcass should be essentially chilled and temperature of meat cutting room should be 15-20oC with relative humidity of about 80%.

Principle

Cyanide is distilled from chloroform and water soultion into KOH solution, forming potassium cyanide. KCN is titrated with silver nitrate; 2 KCN + AgNO₃ = KCN. AgCN + KNO₃. An excess of AgNO₃ produces insoluble AgCN, which is the end point of titration.

The world’s greatest source of cow and buffalo diversity is India, and countries like Australia, South Africa, Latin America, and the USA employ Indian cattle breeds to grow their livestock industries. The number of cattle in the nation represents 17% of all cattle in the world. 22-25% of the Indian cow population is made up of the best native milk, draught, and dual-purpose animal genetics. The majority of local cattle breeds are excellent drafters. Native livestock breeds are clearly superior in their use of subpar feed, have better heat tolerance, and greater resistance to tropical diseases.

All across the world, the dairy industry is facing numerous problems and changes. Dairy development has received a considerable boost from factors including access to technical advancements, improvements in infrastructural facilities, and the development of modern marketing insights. It is interesting to see how the dairy sector is changing globally.

Dairy byproducts constitute an important segment of dairy industry. An important criterion in the economic choice of any process is the efficient utilization of byproduct that is produced along with the main product. The main byproducts of dairy industry are skim milk, buttermilk, whey and ghee residue. Each and every component of milk must be judiciously processed into edible form not only to improve the profitability of dairy industry but also to make best use of the unique nutritional value of the precious milk constituents on one hand, and to prevent environmental pollution, on the other. However, dairy plants, particularly in India, are usually confronted with the problem of byproduct utilization, especially that of whey and ghee residue in economical manner.

Skim milk is a byproduct obtained during the manufacture of cream. It is rich in solids-not-fat content and has high nutritional value. In dairy plants, it is mostly utilized either in standardization for the manufacture of main dairy products or preserved by removing moisture in milk powder form. The skim milk when utilized in either of these two forms or consumed as liquid, is not considered a byproduct. It is regarded as a byproduct only when it is either not economically utilized or utilized for derived byproducts, like casein and other related products, co-precipitates, protein hydrolyzates, etc.

Buttermilk is the byproduct obtained during butter manufacture. Sweet cream buttermilk resembles skim milk in gross chemical composition and is usually admixed with bulk of skim milk for further spray drying or even product manufacture in dairy plants. Desi buttermilk, on the other hand, has long been an important domestic beverage in India. It has high nutritive and therapeutic value. It also finds its way in the preparation of a host of culinary dishes such as kadhi, dhokla and idili. Also a number of federations and private plants sell salted and spiced buttermilk in 200 ml pouches.

Operation Flood and dairy cooperatives became India’s greatest rural employment programme, enabling the modernization of the dairy industry to a point from where it may take off to fulfill the need for milk and milk products within the nation as well as chances on the international market. An unorganized sector handles 80% of the milk a rural producer produces, and an organized sector handles the remaining 20%. It has been discovered that dairy cooperatives significantly contribute to reducing rural poverty by increasing rural milk production and marketing.

Milk processing plants involve processing of raw milk into products like market milk, cheese, butter, ice cream, condensed milk, dried milks and traditional dairy products. The by-products processing includes buttermilk, whey and its derivatives. Dairy effluents contain dissolved sugar, protein, fat and minerals. Spills and leaks of products or by-products, residual milk or milk products in piping and equipment before cleaning, wash solutions from equipment and floors, condensate from evaporation processes and cheese trimmings are some of the sources of dairy effluents in a dairy plant. The key parameters are the biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids, total dissolved solids etc. Common dairy waste techniques include grease traps, oil water separators for separation of floatable solids, equalization tanks. Biological treatment consists of aerobic and anaerobic process.

India has the highest livestock population in the world with 50% of the buffaloes and 20% of the world’s cattle population, most of which are milch cows and milch buffaloes. The dairy industry in our country is considered as one of the most successful development programmes in the post-Independence period. In the year 2006-07the total milk production in the country was over 94.6 million tonnes with a per capita availability of 229 gm. per day. The industry had been recording an annual growth of 4% during the period 1993-2005, which is almost 3 times the average growth rate of the dairy industry in the world. Milk processing in India is around 35%, of which the organized dairy industry account for 13% of the milk produced, while the rest of the milk is either consumed at farm level, or sold as fresh, non-pasteurized milk through unorganized channels. Dairy Cooperatives account for the major share of processed liquid milk marketed in the India. Milk is processed and marketed by 170 Milk Producers’ Cooperative Unions, which federate into 15 State Cooperative Milk Marketing Federations. Over the years, several brands have been created by cooperatives like Amul (GCMMF), Vijaya (AP), Verka (Punjab), Saras (Rajasthan). Nandini (Karnataka), Milma (Kerala) and Gokul (Kolhapur). Uttar Pradesh, Punjab, Haryana, Rajasthan, Gujarat, Maharashtra, Andhra Pradesh, Karnataka and Tamil Nadu are the milk surplus states in India.

Dairy Industry in India
Milk holds a deeply symbolic place in Indian culture, far beyond its role as a mere food item. It is intricately woven into the cultural and historical identity of the nation, with the dairy industry serving as a cornerstone of India’s economy. The sector is a driving force behind rural development providing a crucial pathway to prosperity for millions of small-scale farmers. It plays a significant role in alleviating poverty and generating employment opportunities. The dairy sector by empowering farmers, developing modern infrastructure embracing technological advancements, and promoting sustainable practices, fostering widespread socio-economic progress in rural India. In the 1920s, modern milk processing and marketing technologies were introduced in India. The National Dairy Development Board (NDDB; founded in 1965), implemented Operation Flood (1970-96) to modernize the dairy sector through cooperatives. This led to the rise of dairy cooperatives countering the exploitation by private milk plants. The cooperatives followed the Anand model, a three-tier structure comprising village-level societies (producers), district-level unions (milk collection and processing), and state-level federations (marketing). Originating in Anand, Gujarat in 1946, the model was later adopted nationwide. The progress termed as White Revolution transformed India from a nation struggling with milk shortages into the world’s largest producer and consumer of milk. By 1997, India became the global leader in milk production with a volume of 70.9 million tons, surpassing the United States (FAO data rearranged by Our World in Data). Further in the year 2014, for the first time, it beat the entire European Union. Since 1950, India’s milk production has seen tremendous growth, rising from 17 million tonnes in 1950-51 to 230.58 million tonnes in 2022-23. The per capita availability of milk increased from 124 g/day in 1950-51 (PIB 2022) to 459 g/day in India during.