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Here are some important studying material (Syllabus, Books, Lecture's notes, Old question, Numerical solution etc) on various subjects of 7th semester. These  materials would be very useful for student, researcher, co-worker related to the field of Agricultural Engineering.


   


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Everybody is talking about climate change. It is of course a great and global concern today. It is in the newspapers, on the radio and many books have already been published with reference to the global climate change. Climate change is howsoever not a new phenomenon but a consistent feature of global climate. Indeed the earth has experienced the longest period of consistently warm temperature since the beginning of the earth. These extreme warming of earth arises from the production and consumption pattern of non poor people of particularly of rich countries. They consume a lot of fossil fuels and deplete many of the world resources damaging the precious global environment yielding an uncertain climate.

        It is of course a great and global concern today because the global leaders in very soon will going to take part in a Climate Change Conference with less than 30 days. The main concern of this uncertain climate is the nose-diving agricultural production and productivity making the hungrier world. Global climate change is expected to increase the economic disparities between the rich and non-rich poor people particularly in the developing countries like Nepal. Nepal emits only 0.025 % of the total GHG's (green house gas emissions) of the world but serious challenges had been seen throughout the country.
The estimated damage for the poor countries like Nepal partly reflects the weaker adaptive capacity and there is no alternative of adoption. Hence, climate change is a major developmental issue and thus in the upcoming conference the policy priest of Nepal should need to address all the possible impacts of climate change in all sectors of the society.

Most spectacular symptoms are already seen in our country. The highest peak of the world Mount Everest is in threat, the rain these days are unpredictable and we also faced dry spells at the critical stages of crop growth. Many farmers of the country are not able to transplant Paddy in the Ashad(the man paddy transplanting time in country).U.N. Intergovernmental Panel on Climate Change quotes a 0.76degree Centigrade increases  in the world's average temperature in the last century expecting temperature to rise by a 2 degree Centigrade by 2050. This is leading to rising sea levels, outburst of GLOF's, the disappearance of glaciers, drastic changes in rainfall patterns, flood and storms, loss of precious agro-biodiversity and thus affecting the production of agriculture.

Nepal, because of its unique and fragile mountain ecosystem is more vulnerable to climate change. Also being an agricultural country as agriculture is based on the ecological process the deleterious effects of climate change has affecting the agricultural production process. Most rural areas of Nepal had experienced climatic variability and farmers had to cope with a degree of uncertainty in relation to local weather. Howsoever, agricultural production today are nose-diving as a result of increased exposure to drought, rising temperature, more erratic rainfall, etc. Higher temperatures as a result of climate change also have unfavorable effects on pests and diseases in the crop's fields. These deleterious effects become more prominent, frequent and intense with this uncertain climate. The vulnerability of climate change depends upon the farmer's adaptive capacity to cope with stress and drought.


Food Security had been described as a condition in which people has adequate basic food intake to provide them with the energy and nutrients to fully productive lives. For the food security the agriculture now a day was shifted towards a modern so often called Green Revolution. But this shift rather benefit, intensifies the deleterious effects of climate change. This is mainly due to changes in land us e patterns intensified agriculture coupled with deforestation, monoculture, soil degradation and erosion. It is   to be expected that climate change will further accelerate the ongoing degradation process in many cases leading to a complete collapse of the universal systems.

Food crisis is not only a problem of the developing countries like Nepal but it is a global tragic. It had a catastrophic impact on several developing countries. Food Security is also a global issue in this time of uncertain climate. The world leaders are meeting together for seeking a synergistic solution to the food crisis in the November 14-16, in Italy for 3rd World Food Security Summit Conference. So, it is of course a great need of the hour to make our agriculture and food system more just ecological and truly effective in food security.

Systems with more diversity or which successfully integrate livestock are often less vulnerable to the sudden catastrophic changes and show higher levels of resilience. These practices are opting by small scale farmers in the developing countries to bring resilience to climate. Scientific studies had also shown that these practices are more productive than industrial farming (the so often called Modern Agriculture which in our 20 years Agriculture Perspective Plan also mentioned) and also they are more sustainable. Throughout history small scale farmers have developed specific farming systems which perform best in their given situation or very often the farmer's wisdom in relation to the local weather. Rather the farmer's wisdom to adapt the climate change and making the agricultural production system more sustainable Nepalese farmers are hurting due to the government's mulct policy to the small scale farmers. The speed of the deleterious effects of the global climate change has in accelerating stage. Nepalese farmers are facing double disadvantages; by the uncertain climate and the government's mulct policy. These factors had intensifying the hunger in the Nepal and become increasingly dependent on food imports.

Government of Nepal(GoN) should need to pay attention to the impact of climate change on Nepalese farming society otherwise the climate change will drifts a "tipping point" that would lock  the Nepalese farmers in a downward spiral , leaving their families facing malnutrition , water scarcity , ecological threats and a loss of livelihoods . GoN also is clock up the National Adaptation Program Action (NAPA) preparation. Million of dollars are downpour for it s preparation so the people taking advantage of policy priest for NAPA preparation should need to address all the possible sectors affected by climate change.

Agriculture is the foundation to Food Security, Environment protection, Social justice and Development. Thus, it seems the major sector affected by climate change in Nepal. The farmer's wisdom to bring resilience in this uncertain climate should need to properly supported and focused on maintaining healthy and living soil and organized around a broad use of locally available biodiversity shows the way to kick out the food crisis in this uncertain climate.

Several traditional farming techniques shows the farmer's wise skill to reduce the green house gas emissions by reducing the use of chemical fertilizers, minimizing the use o fossil fuels, incorporating nitrogen into the soil, avoiding the loss of organic matter and improving the use of manure. Also, at the same time, the farmer can help to sequester the carbon by restoring the natural vegetation where this is possible avoiding deforestation and efficiently managing their soils.

As reported by UN: IPCC, Green Peace and FAO, there is a large mitigation potential in agriculture, which is directly related to the implementation of the sustainable agriculture practices. Thus, it is a great need of the hour to shift the way of agriculture towards sustainable agriculture which reflects a truly "win-win" situation. There is no way of tackling food insecurity without addressing the issues of sustainable agriculture. Thus, it is essential to develop and disseminate eco-friendly production system which can benefit farmers, their r families, support rural communities and produce healthy foods for the consumers. At the meanwhile, fighting climate change is about our commitment to create ecological security along with food security for our children and their grand children.

 So, rather wait and see for ready made solutions by the developed countries in their situations ,we need to foster an agriculture that is inclusive, multi-functional and built on principles of resilience that are crucial to ensure food security in an uncertain climate.
Article by
Dipendra Pokharel
Agronomist
District Agriculture Development Office
Sunsari, Nepal

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DAIRY AND FOOD ENGINEERING
AE ..

Lectures   :   3                                                                                              Year   :   IV   
Tutorials  :   1                                                                                              Part    :   I      
Practical   :   2                                                                                                                     
Course Objectives:
·         To acquaint and equip the students with different unit operations of Dairy industries.
·         To acquaint and equip the students with different forms of moisture, water activity and its relation with food safety.
·         To acquaint and equip the students with different preservation techniques employed in Dairy and Food industries.
1.       Dairy Development in Nepal:                                                                   [5 hours]
1.1.  Engineering, thermal and chemical properties of milk and milk products
1.2.  Unit operation of various dairy and food processing systems in Nepal
1.3.  Process flow charts for product manufacture
1.4.  Working principles of equipment for receiving, pasteurization, sterilization, homogenization, filling & packaging
2.       Heat Processing:                                                                                          [5 hours]
2.1.  Methods of applying heat to food Sterilisation
2.2.  Batch and continuous retorts, their working principle
2.3.  Thermal bacteriology: TDR and TDT curve, D-value, z-value and F-value
2.4.  Heat penetration curve
2.5.  Processing time by formula and graphical method
3.       Deterioration in Products and their Controls:                                      [5 hours]
3.1.  Physical, chemical and biological methods of food preservation
3.2.  Changes undergone by the food components during processing 
3.3.  Butter manufacturing
3.4.  Dairy plant design and layout
3.5.  Composition and proximate analysis of food products
4.       Evaporation:                                                                                                 [7 hours]
4.1.  Basic concepts of evaporation
4.2.  Types of heat exchangers
4.3.  Working principle of a single effect evaporation system
4.4.  Heat and mass transfer in evaporator
4.5.  Evaporator capacity, overall heat transfer co-efficient
4.6.  Evaporator economy and capacity
4.7.  Multiple effect evaporation system, it’s working principle and economy
4.8.  Different arrangements of triple effect system and their principle
5.       Dehydration and Drying:                                                                           [7 hours]
5.1.  Free moisture, bond moisture
5.2.  Equilibrium moisture content
5.3.  BET equation, Water activity and its estimation
5.4.  Classification of driers: hot air, heated surface, microwave etc.
5.5.  Tray, drum and spray, foam mat drier for liquids and pastes, 
5.6.  Vacuum, fluidized bed, osmotic drying: mechanism & working principles
6.       Freezing:                                                                                                       [7 hours]
6.1.  Low temperature preservation
6.2.  Theory of freezing
6.3.  Nucleation and ice crystal growth   
6.4.  Freezing plateau
6.5.  Calculation of freezing time by Plank’s equation
6.6.  IQF, Effect of freezing on product   
6.7.  Frozen products
6.8.  Effect of frozen storage
6.9.  Commercial freezers and cryogens: CO2, liquid N2
7.       Freeze drying:                                                                                              [5 hours]
7.1.  Theory of Lyophilization
7.2.  Phase diagram of water
7.3.  Heat and mass transfer in freeze drying
7.4.  Calculation of freeze drying time
7.5.  Freeze dried foods
8.       Concentration:                                                                                            [2 hours]
8.1.  Theory of Concentration
8.2.  Freeze Concentration
8.3.  Membrane Concentration: reverse osmosis and ultra filtration
9.       Irradiation:                                                                                                   [2 hours]
9.1.  Theory of irradiation, effect on foods
9.2.  Microwave heating
9.3.  Dielectric heating of foods


Tutorial: – 12 tutorials from relevant chapters/topics.

Practicals:
1.       Study of a composite pilot milk processing plant & equipments        [3 hours]
2.       Study of pasteurizers                                                                                  [2 hours]
3.       Study of sterilizers                                                                                       [2 hours]
4.       Study of homogenizers                                                                               [2 hours]
5.       Study of separators                                                                                     [3 hours]
6.       Study of butter churners                                                                           [3 hours]
7.       Study of evaporators: PHE                                                                         [2 hours]
8.       Study of milk dryers                                                                                    [3 hours]
9.       Study of freezers                                                                                         [3 hours]
10.    Estimation of refrigeration requirements in dairy & food plant         [3 hours]


Visit:
Visit to nearby multiproduct dairy or food industry and submit a detail report including working principle, equipment drawing and procedure and efficiency of the available equipments if moderate dairy or food factory is available in the vicinity.



Reference:
1.       Sukumar De, Outlines of Dairy Technology, Oxford University press, Delhi.
2.       Tufail Ahmad. Dairy Plant Engineering and Management, (latest edition), Kitab Mahal,
3.       Brennan JG, Butters JR, Cowell ND & Lilly AEI. 1990. Food Engineering Operations. Elsevier.
4.       Earle RL. 1985. Unit Operations in Food Processing. Pergamon Press.
5.       Fellows P. 1988. Food Processing Technology: Principle and Practice. VCH Publ.
6.       Geankoplis J Christie. 1999. Transport Process and Unit Operations. Allyn & Bacon.
7.       Henderson S & Perry SM. 1976. Agricultural Process Engineering. 5th Ed. AVI Publ.
8.       McCabe WL & Smith JC. 1999. Unit Operations of Chemical Engineering. McGraw Hill.
9.       Verma R. C. & Sanjay Kr jain. Fundamentals of Food Engineering. Himanshu publications Udaipur.
10.    Coulson JM & Richardson JF. 1999. Chemical Engineering. VolS. II, IV. The Pergamon Press.


Evaluation Scheme:
The questions will cover all the chapters in the Syllabus. The evaluation scheme will be as indicated in the table below.
Chapter
Hours
Marks Distribution*
1
5
8
2
5
8
3
5
8
4
7
12
5
7
12
6
7
12
7
5
8
8
2
8
9
2
Total
45
80
*There may be minor variation in marks distribution.
Source:- Department of Agricultural Engineering

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