Challa Ravi Kiran; Dr Sundresan, A(Cochin University of Science and Technology, June , 2015)
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Abstract:
Deep fat frying process is one of the widely followed cooking practices throughout the
world. Cooking oils serve as a medium for frying food for transferring heat and makes fried
food tasty and palatable. Frying process is a most complex process involving numerous
physicochemical changes which are complicated to understand. Frying leads to thermal
degradation of oil through thermo-oxidation, hydrolysis, and polymerization. Hydrolysis
results in formation of free fatty acids whereas oxidation process produces hydroperoxides
and small molecular carbonyl compounds. This whole process leads to the formation of polar
compounds and degradation of antioxidants that further degrades frying oil. Eventually,
through mass transfer process these degradation products accumulate into fried food and
reduce the nutritional quality of both oil and food. Thus, the frying process is of research
interest calls for detailed systematic study which is chosen for the present study. The primary
objective of this study is to understand the mechanism of degradation and characterization ofdegraded products which helps in arriving at the limits for frying oil utilization in terms of
number of frying cycles. The mechanistic studies and the knowledge on the degraded
products help to understand the way to retard the deterioration of oil for stability and
enhancement of frying cycles. The study also explores the formation of the predominant
polar compounds and their structural elucidation through mass spectrometry. Oxidation of oil
is another important factor that ignites the degradation phenomena. One of the best ways to
increase thermal stability of any oil is addition of potent antioxidants. But, most of the natural
and synthetic antioxidants are unstable and ineffective at frying temperatures. Therefore, it is
necessary to screen alternative antioxidants for their activity in the refined oils which are devoid of any added antioxidants. In this context, this study discussed the efficacy of several
natural and synthetic antioxidants to retard the formation of polar compounds and thermooxidation
during prolonged frying conditions. Similarly, the advantage of blending of two
different oils to improve the thermal stability was explored. The present study brings out the
total picture on the type of degradation products formed during frying and the ways of
retarding the determination to improve upon the stability of the oil and enhancement of frying
cycles.
Bindu, J; Dr. Srinivasa Gopal, T K(Cochin University of Science and Technology., March , 2009)
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Abstract:
This study is the first of its kind in India, where in smoked and thermal
processed products have been developed using locally available wood as the
source of wood smoke and flavoring and a shelf life of one year has been
achieved. Retortable pouches of three layers, both imported and indigenous
were found suitable to store thermal processed products. Heat penetration rate is
quicker in retort pouches due to their thin profile in comparison to cans and
hence the total process time is lesser. The nutritional and sensory attributes of
the pouch products are better retained during processing. Hence these products
are more acceptable than canned products. lndian vegetarian food products and
fish curry products are available in the ready to eat form in the markets. Smoked
and thermal processed products have not gained an entry to the market and
hence this study will pave an opening for such products. Currently trade in tuna
products from India is meager compared to the global trade. ln India proper
utilization of tuna resources is yet to be achieved due to the lack of infrastructure
for handling and knowledge of value addition. The raw material cost is also less
due to the poor quality of the fish when landed. Hence, the availability of such
products will help in the trade of tuna products, improving the quality of raw
material landing and ultimately realizing a better value to the fishermen and
processors.
Manjusha, M V; Dr. Jacob, Philip(Cochin University of Science and Technology, May , 2008)
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Abstract:
Photothermal spectroscopy is a group of high sensitivity methods used to measure optical absorption and thermal characteristics of a sample.The basis of photothermal spectroscopy is a photo-induced change in the thermal state of the sample.Light energy absorbed and not lost by subsequent emission results in sample heating.This heating results in a temperature change as well as changes in thermodynamic parameters of the sample which are related to temperature.Measurements of the temperature,pressure,or density changes that occur due to optical absorption are ultimately the basis for the photothermal spectroscopic methods.This is a more direct measure of optical absorption than optical transmission based spectroscopies.Sample heating is a direct consequence of optical absorption and so photothermal spectroscopy signals are directly dependent on light absorption.Scattering and reflection losses do not produce photothermal signals.Subsequently,photothermal spectroscopy more accurately measures optical absorption in scattering solutions,in solids,and at interfaces.This aspect makes it particularly attractive for application to surface and solid absorption studies,and studies in scattering media.
Description:
Department of Instrumentation,
Cochin University of Science and Technology
Mohanan, P V; Dr.Chandrasekaran,M(Cochin University of Science And Technology, August , 1995)
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Abstract:
Microbial enzymes are in great demand owing to their
importance in several industries such as brewing, baking,
leather, laundry detergent, dairy. starch processing and
textiles besides pharmaceuticals. About 80% of the enzymes
produced through fermentation and sold in the industrial scale
are hydrolytic enzymes. Due to recognition of new and new
applications, an intensive screening of different kinds of
enzymes with novel properties, from various microorganisms, is
being pursued all over the world. Bacillus sp are largely known to produce a-amylase, among the different groups of microoganisms, at industrial level. They are known to produce both saccharifying and liquefying a-amylases (Fukumoto 1963; walker and Campbell, 1967a). which are distinguishable by their mechanisms of starch degradation by the fact that the saccharifying asamylases produce an increase in reducing power about twice that of the liquefying enzyme (Fukumoto, 1963; Pazur and Okada, 1966). Under this circumstances, the present study was
undertaken, with a View to utilise a fast growing B.coagu1ans
isolated from soil, for production of thermostable and
alkaline oz-amylase under different fermentation processes
Description:
Department of Biotechnology, Cochin University of Science And Technology
Hareeshkumar, P V; Dr.Basil, Mathew(Cochin University of Science And Technology, January , 1992)
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Abstract:
The Arabian Sea is an area of complex air-sea interaction
processes with seasonal reversing monsoons. The associated
thermohaline variability in the upper layers appears to
control the large scale monsoon flow which is not yet
completely understood.
The variability in the thermohaline fields is known to
occur in temporal domain ranging from intra-diurnal to
inter-annual time scales and on spatial domains of few tens of
kilometers to few thousands of kilometers. In the Arabian Sea
though the surface temperature was routinely measured by both
conventional measurements and satellites, the corresponding
information on the subsurface thermohaline field is very
sparse due to the lack cw adequate measurements. In such
cases the numerical models offer promise in providing
information on the subsurface features given an initial
thermohaline field and surface heat flux boundary conditions.
This thesis is an outcome of investigations carried out
on the various aspects of the thermohaline variability on
different time scales. In addition to the description of the
mean annual cycle. the one dimensional numerical models of
Miller (1976) and Price et a1 (1986) are utilised to simulate
the observed mixed layer characteristics at selected locations
in the Arabian Sea on time scales ranging from intra-diurnal
to synoptic scales under variable atmospheric forcing.
Anju, K. Augustine; Dr.Kailasnath, M; Prof. V P N Nampoori(Cochin University of Science and Technology, June 23, 2015)
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Abstract:
In general, linear- optic, thermo- optic and nonlinear- optical studies
on CdSe QDs based nano
uids and their special applications in solar
cells and random lasers have been studied in this thesis. Photo acous-
tic and thermal lens studies are the two characterization methods used
for thermo- optic studies whereas Z- scan method is used for nonlinear-
optical charecterization. In all these cases we have selected CdSe QDs
based nano
uid as potential photonic material and studied the e ect of
metal NPs on its properties.
Linear optical studies on these materials have been done using vari-
ous characterization methods and photo induced studies is one of them.
Thermal lens studies on these materials give information about heat
transport properties of these materials and their suitability for applica-
tions such as coolant and insulators. Photo acoustic studies shows the
e ect of light on the absorption energy levels of the materials. We have
also observed that these materials can be used as optical limiters in the
eld of nonlinear optics. Special applications of these materials have
been studied in the eld of solar cell such as QDSSCs, where CdSe QDs
act as the sensitizing materials for light harvesting. Random lasers have
many applications in the eld of laser technology, in which CdSe QDs
act as scattering media for the gain.
Santhosh, B; Dr.Nandakumar, C G(Cochin University of Science & Technology, December , 2010)
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Abstract:
Three dimensional (3D) composites are strong contenders for the structural applications in situations like aerospace,aircraft and automotive industries where multidirectional thermal and mechanical stresses exist. The presence of reinforcement along the thickness direction in 3D composites,increases the through the thickness stiffness and strength properties.The 3D preforms can be manufactured with numerous complex architecture variations to meet the needs of specific applications.For hot structure applications Carbon-Carbon(C-C) composites are generally used,whose property variation with respect to temperature is essential for carrying out the design of hot structures.The thermomechanical behavior of 3D composites is not fully understood and reported.The methodology to find the thermomechanical properties using analytical modelling of 3D woven,3D 4-axes braided and 3D 5-axes braided composites from Representative Unit Cells(RUC's) based on constitutive equations for 3D composites has been dealt in the present study.High Temperature Unidirectional (UD) Carbon-Carbon material properties have been evaluated using analytical methods,viz.,Composite cylinder assemblage Model and Method of Cells based on experiments carried out on Carbon-Carbon fabric composite for a temparature range of 300 degreeK to 2800degreeK.These properties have been used for evaluating the 3D composite properties.From among the existing methods of solution sequences for 3D composites,"3D composite Strength Model" has been identified as the most suitable method.For thegeneration of material properies of RUC's od 3D composites,software has been developed using MATLAB.Correlaton of the analytically determined properties with test results available in literature has been established.Parametric studies on the variation of all the thermomechanical constants for different 3D performs of Carbon-Carbon material have been studied and selection criteria have been formulated for their applications for the hot structures.Procedure for the structural design of hot structures made of 3D Carbon-Carbon composites has been established through the numerical investigations on a Nosecap.Nonlinear transient thermal and nonlinear transient thermo-structural analysis on the Nosecap have been carried out using finite element software NASTRAN.Failure indices have been established for the identified performs,identification of suitable 3D composite based on parametric studies on strength properties and recommendation of this material for Nosecap of RLV based on structural performance have been carried out in this Study.Based on the 3D failure theory the best perform for the Nosecap has been identified as 4-axis 15degree braided composite.
Description:
Dept.of Ship Technology,Cochin University of Science and Technology
Shivaprasad,Amaravayal; Dr.Revichandran,C(Cochin University Of Science And Technology, May , 2013)
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Abstract:
Hydrodynamic characteristics of an estuary resulting from
interaction of tide and river runoff are important since problems
regarding flood, salinity intrusion, water quality, ecosystem and sedimentation are ubiquitous. The present study focuses on such
hydrodynamic aspects in the Cochin estuary.
Most of the estuaries that come under the influence of Indian
Summer Monsoon and for which the salinity is never in a steady
state at any time of the year are generally shallow and convergent,
i.e. the width decreases rapidly from mouth to head. In contrast,
Cochin estuary is wider towards the upstream and has no typical
river mouth, where the rivers are joining the estuary along the length
of its channel .Adding to the complexity it has dual inlets and the
tidal range is 1 m which is lower than other Indian estuaries along
west coast. These typical physical features lead to its unique
hydrodynamic characteristics. Therefore the thesis objectives are: I)
to study the influence of river runoff on tidal propagation using
observations and a numerical model ii) to study stratification and
property distributions in Cochin estuary iii) to understand salinity
distributions and flushing characteristics iv) to understand the
influence of saltwater barrage on tides and salinity v) To evaluate
several classification schemes for the estuary
Description:
National Institute of Oceanography, Regional centre, Cochin- 18
Suresh, V N; Dr.Wilson, P R(Cochin University of Science And Technology, June , 2000)
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Abstract:
Poor project planning, implementation and control and the subsequent cost and time overruns are ubiquitous features that have been posing serious concern at all levels - state, national and international. It results in wastage of the nation's scarce resources and retards the socio-economic progress. Although several studies peripheral on project overruns have been made at the national level, no serious attempt has been made at the state level to identify the magnitude of overruns, their causes and impacts on industrial projects. The present study "Time and Cost Overruns of Industrial Projects in Kerala" is an earnest attempt to probe in depth the time and cost overruns and their impact on industrial projects. The study places emphasise on the identification of the real reasons behind the cost and time overruns. It also covers the present project management practices of industrial projects in Kerala.
Description:
School of management studies, Cochin University of Science And Technology