V, SRIDHAR

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CHAPTER 6 Summary and Conclusion ________________________________________________________________​​​​​​​_____________Traditional foods have occupied an unique place in the dietary practices of population in different countries (Kulkarni, 1989) and are known for their unique texture and taste. The art of preparing traditional foods has been evolved over thousands of years with each region in the world having its own characteristic products. These foods are prepared in every part of the world based on the traditional knowledge enriched through many generations. In traditional foods, snack foods hold a significant share. Webster’s New Ninth Collegiate Dictionary (1985) defines the noun ‘snack’ (First recorded use, 1757) as ‘a light meal, foods eaten between regular meals, food suitable for snacking’ and the verb snack as ‘to eat a snack’. Kulkarni (1989) stated that snacks, which are mostly based on the locally available raw materials, originated probably from a need to overcome the monotony in the diet. In India, Ministry of Food Processing, India (MFPI) estimates that the size of the food processing Industry is Rs.3150bn (US$70bn), including Rs.990bn (US$22bn) of value added products and it is expected to grow at the rate of 9-12% annually on the basis of an estimated GDP growth rate of 6-8% during the tenth plan period. Estimated Indian snack food market is over 400000 tons in terms of volume and Rs.100bn in terms of value and has grown at over 10% per year during the period 2000-2003.  Among the innumerable traditional foods of India, snack food items are very popular, especially those based on fried legume. Legumes and pulses play an important role in the Indian diet for they supplement not only the quantity and also quality of protein by balancing essential amino acid pattern in the predominantly cereal based diet of bulk of Indians. They are good sources of lysine rich protein. The world total pulse production in the year 2003 (FAO, 2004) was 55520000 MT and India’s production was 11933000 MT which contributes nearly 21% of the world’s production.The chickpea cultivars Desi (A1) and Kabuli (L 550) vary significantly in their physical properties like seed  color, size 100 seed weight, 100 seed volume. The color related parameters such `L’, `a’ and `b’ showed significant differences between the cultivars indicating kabuli variety having lighter color compared to desi. The volume and weight of 100 seeds was also higher for kabuli variety while its true density was lower.  Broad objectiveThe proposed investigation will focus on the process of boondi preparation, and to understand the role of raw material, additives and processing parameters on the product characteristics including rheological and sensory characteristics. Specific Objectives	To investigate the effect of popular Kabuli and Desi chickpea varieties available in India and examining their suitability for boondi making.	Detailed rheological characterisation of the chickpea flour suspensions and sensory quality of the product.	To study the effect of additives on rheology of chickpea suspensions and standardisation of process parameters of boondi.	Finding the relationship among rheological, textural and sensory properties.Plan of Work	Suitability of Kabuli (Variety - L550) and Desi (Variety - A1) types of chickpea for the preparation of boondi. 	Assessing the quality characteristics of commercially available boondi with an emphasis on texture and sensory attributes. 	Rheological studies of  Kabuli’ and Desi type chickpea flour suspensions	Effect of additives, such as, refined groundnut oil, sodium chloride (NaCl), sodium salt of Carboxy methyl cellulose (Na CMC), and guar gum on the rheology of chickpea suspensions and quality characteristics of  prepared boondi based on instrumental and sensory analysis.	Standardisation of the process parameters of boondi making using an integrated approach of relating rheological characteristics, process parameters and product quality.Chapter 1 covers the introduction regarding legume based products in general and also fried snacks from pulses and in combination with cereals. Available information on Chickpea has been classified under cultivars yield, composition, of major and minor constituents and the effect of commonly used processing steps on these constituents. However, published literature covers very little information regarding the detailed sensory and instrumental characteristics of chickpea based products and the necessity for undertaking boondi a fried product from chickpea as a case study for a systematic investigation gets justified. Chapter 2 mainly describes the physico-chemical properties of the Chickpea cultivars i.e Desi and Kabuli. 	The chickpea cultivars Desi (A1) and Kabuli (L 550) vary significantly in their physical properties like seed  color, size, 100 seed weight and 100 seed volume.  	The color related parameters such `L’, `a’ and `b’ showed significant differences between the cultivars indicating kabuli variety having lighter color compared to desi. The volume and weight of 100 seeds was also higher for kabuli variety while its true density was lower. 	Between the dry and wet milling, higher yield of dhal was obtained from wet milling, which was found to be true in both the cultivars. An extra yield of 2 to 4% was obtained in wet milling. Between the cultivars, Desi was found to be the higher dhal yielding cultivar in both dry and wet milling methods. 	SEM microphotographs of Kabuli chickpea were found to be similar to that of Desi variety, but the split dhal surface showed some difference in the pattern.	After grinding the flour obtained was sieved and the particle size distribution showed indicating that 100 to 120mesh particle size forms the major bulk of flour. However, marginal differences in yield of different fractions were observed between the two varieties. 	Fat, ash and protein contents were more in kabuli than desi and fibre content was more in desi than Kabuli.	Electronic nose analysis of chickpea flour, indicated the possibility of differentiating the variations in odor associated with varietal difference and also dhal obtained from dry or wet milling of the gram.  Grinding of dhal at low speed could be easily separated as the difference in odor was relatively larger. 	The gel electrophoresis pattern of chickpea showed that as about fifteen protein bands in flours from both the cultivars, either in phosphate or SDS buffer containing ß-mercapto-ethanol. There were some differences observed in the band thickness but the pattern was very similar.	The Rapid Visco Aanalyzer profile did not show significant difference between the two cultivarsChapter 3 deals with the rheological properties of Chickpea flour dispersions. and modeling. The rheological studies were conducted for time independent as well as time dependent properties of chickpea flour dispersions. 	Time independent rheology of chickpea flour dispersions were measured as a function of shear rate, up to 500s-1. Apparent viscosity and shear stress were measured. The shear rate / stress and apparent viscosity data were analyzed by fitting with well known rheological models namely., Herschel-Bulkley and Cross equations.	Chickpea flour dispersions behave like a pseudoplastic or shear-thinning fluid. The pseudoplastic behavior indicates the continuous breakage or re-organisation of structures, resulting in a decrease of resistance when applying force. The pseudoplastic behavior is due to the presence of a) compounds with high molecular weight or particles at low concentrations b) high interaction among particles, causing their aggregation or association by secondary bonds c) large axial relation and asymmetry of the particles, requiring their orientation along the stream lines d) variation of shape and size of the particles, allowing them to pile up. and e)  Non-rigid or flexible particles that can suffer a change in their geometry or shape. 	The apparent viscosities measured at a shear rate of 100s-1, increased from 213 to 1497.3 mPa s. when the concentration of solids in the dispersion increased from 34 to 44% in desi flour.	The Cross model constants were significantly affected by the influence of solids concentration in the dispersion. The zero shear viscosity increased from 437.10 to 4218.87 Pas when the solids concentration increased from 34 to 44%. The relaxation parameter () also increased from 0.0102 to 0.0179s along with ‘m’ which also increased from 0.1213 to 0.2586. The increase in ‘m’ values indicated that the flow behaviour decreased with the increasing concentration of solids in the dispersion. The same was also reflected in the power law constant ‘n’ which is known as the flow behaviour index. 	As fine particles have more surface area, leaching out of soluble and / or colloidal particles to dispersion is higher which leads to higher  values for smaller particles (<100 microns).	Among the additives used in the present study, salt and oil reduced the viscosity of the chickpea flour dispersions while CMC exhibited a reverse trend. 	Guar gum, gum Arabic and pre gelatinized rice and corn starches were added to  chickpea flour dispersions at various levels. Gums increased the viscosity at much lower levels compared to modified starches. 	Chickpea flour dispersions exhibited time-dependent characteristics that were affected by the temperature of measurement and the shear-rate employed. The models of Peleg, Weltmann and Hahn-Ree-Eyring were suitable to characterize the time-dependent rheological behavior of chickpea flour dispersions while the model of Peleg was marginally better as evidenced by the lowest root mean square (RMS) error values of 0.77 to 5.17%. The coefficients obtained from these models indicated that higher breakdown occurred at low temperature as well as at high shear-rates. Chapter 4 deals with bench mark studies from market samples of boondi along with laboratory samples including both instrumental and  sensory characterization.  	PCA analysis was carried out to position these samples which indicated that the market samples segregated with respect to oily and fried gram aroma, firmness and crumbly notes. The color showed greater difference as surface was coated with different levels of chilli powder. They did not show significant difference in other attributes. 	Uniformity of boondi, porosity, firmness and crumbly notes were comparable, fried gram aroma of samples A and B were good, but both oily appearance and mouth feel showed greater differences. Samples A, B, and C differed from D, E and F as the latter had lower oily appearance and oily mouth-feel. They also differed in their firmness values as indicated by the sensory data.	Boondi samples prepared with 40 and 42% solids concentration in the dispersion were located nearer to desirable sensory attributes like uniformity in size and fried gram aroma.	Simultaneous optimization was performed on selected important quality characteristics of boondi like oil content, crumbliness, uniformity of boondi and overall quality, by imposing desirability constraints 	Based on the trails, a maximum desirability score of 0.7074 colud be achieved when the solids concentration in the dispersion, temperature and time were 40.4%, 182°C and 240s, respectively. The predicted corresponding responses were oil content, uniformity of boondi, crumbliness and OQ and their values were 56.34%, 12.82, 8.09 and 12.65 respectively. 	Confirmation of the results were done by making the product boondi with optimized levels and subjected to sensory evaluation by a trained panel. The results indicated that no significant (p<0.05) difference between predicted and experimental values for different attributes, validating the results from optimization studies. 	Correlations of results from rheological measurements and sensory profiling by partial least squares analysis  (PLS) indicated that two Cross model constants such as η0 and flow behavior parameter `m’ were closely associated with uniformity and OQ of boondi.	Textural characteristics of boondi were determined by subjecting to compressive strain at different crosshead speeds from 0.01 to 10 mms-1. The principal component analysis (PCA) was found to be a very useful tool in segregating textural parameters associated with crosshead speeds in boondi. The fracture strain, maximum force and number of peaks were positively related while slope was negatively correlated with crosshead speed. 	Boondi samples made from flour with smaller particle size were harder, less crumbly and crisp. However, boondi from flours with bigger particle size were more crumbly, and porous but more oily. Grinding the dhal to suitable particle size distribution is essential to get boondi with desirable quality attributes. 	High amount of salt (3%) in chickpea flour dispersions resulted in more firm boondi loosing its characteristic crumbly attribute. Samples lower salt level (1-2%)  did not adversely affect the boondi quality.	The desirable golden brown color of boondi was closely associated with samples with low levels of salt (1-2%) and oil (2.5 to 5%).	There was a reduction in the oil content of boondi as it came down from 55.84% to 51.51% when 0.5% of CMC was added, but higher amounts did not result in any beneficial effect. 	There was a marginal reduction in the oil content of boondi, when the gum Arabic level was added at 5.00% level.	The beneficial effect of guar gum in terms of  reduction oil content was not reflected in the texture of boondi as the crispness was lost in the product	Addition of pre gelatinised rice flour improved crispness and resulted in more porous nature of the fried product. Addition of pre gelatinized corn starch at 2.5% resulted in product with lowered oil content. It was less firm compared to control. Addition at 5.0% also showed the similar pattern.Chapter 5 covers the effect of processing on the functional properties of chickpea. The SDS-PAGE electrophoretic pattern from phosphate buffer extracts of chickpea flour indicated the absence of high molecular weight protein bands in the steamed dhal or steamed flour. 	The treated flour samples were used to prepare the fried snack boondi. Evaluation of boondi showed that use of steamed flour or the flour from steamed dhal resulted in loss of spherical shape of the product boondi. 	It was observed that thermal treatment leading to absence of protein band might be due to reduced solubility of protein as indicated by SDS PAGE electrophoresis. 	Thermal treatment of chick pea dhal / flour causes denaturation of this protein fraction, and leads to `loss of solubility’. The flour from thermally treated chickpea flour may be unable to impart spherical shape to boondi. Sphericity is a desirable characteristic of boondi.	The results indicated that some fraction of phosphate buffer soluble protein may be responsible for imparting sphericity to the boondi. Though it is not a common practice to process chickpea for product preparation some amount of heat generated during large scale grinding of chickpea.	Protein extracted from these treated flours, was subjected to gel-filtration chromatography followed by SDS-PAGE and the results indicated that the high molecular weight protein fraction content decreased significantly in heat treated samples compared to control. 	The studies on sensory quality of boondi indicated that the chickpea proteins play a vital role in governing the product texture and quality, which is evident from the changes brought about by absence of high molecular weight protein bands after different thermal treatments as reflected in SDS PAGE electrophoretic pattern and gel filtration chromatography profile.	It is important to note that, care should be exercised during large scale milling of chickpea to avoid excess heat effect on the flour, so that desirable quality characteristics of fried product could be achieved.

IN VITRO EVALUATION OF CYTOTOXIC AND APOPTOTIC PROPERTIES OF THE NOVEL SYNTHETIC QUINAZOLINYL DERIVATIVES AGAINST CANCER CELL LINES

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IN VITRO EVALUATION OF CYTOTOXIC AND APOPTOTIC PROPERTIES OF THE NOVEL SYNTHETIC QUINAZOLINYL DERIVATIVES AGAINST CANCER CELL LINES

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