Thumbnail Image

Theses

Browse

20024
Reset filters
Subject: Agriculture × End date: 2002 × Start date: 2002 × Type: Thesis ×
Reset filters

Search Results

Now showing 1 - 4 of 4
  • Thumbnail Image
    ThesisItemOpen Access
    Value addition and evaluation of nutritional quality in taro (Colocasia esculenta (L.) Schott)
    (Department of Processing Technology, College of Agriculture, Vellayani, 2002) Shamsudeen, Liya; KAU; Philipose Joshua
    A study on "Value addition and evaluation of nutritional quality in taro (Colocasia esculenta (L.) Schott)" was carried out in the Department of Processing technology, College of Agriculture, Vellayani, Thiruvananthapuram during the period 1999- 2001. The objectives of the study were to evaluate four cultivars of colocasia for nutritional quality, to examine the potentiality of developing value added products using colocasia and to assess the storage and shelf life of the colocasia products. The nutritional quality of four cultivars ie., Pathanamthitta local, Vellayani local, Thamarakannan and Sree Rashmi were evaluated. Corms of Pathanamthitta local had the highest starch and calcium oxalate content. Vellayani local exhibited the highest protein and vitamin C content while Thamarakannan had the highest total sugar content. The crude fibre contents of all the four cultivars were on par. Sree Rashmi recorded the maximum organoleptic quality. In case of leaves protein content and organoleptic quality were high in Sree Rashmi while total sugars was maximum in Pathanamthitta local. Vitamin C content was high in leaves of Thamarakannan while Vellayani local recorded the highest calcium oxalate content. Value addition was done through preparation of chips and traditional snack items viz., Murukku, Wafers and Papads. Chips were prepared by two techniques ie. by freshly frying and by parboiling and frying. Oil uptake was the highest in chips of Vellayani local and it was seen that oil uptake increased with increasing thickness. Parboiling helped to reduce the oil uptake significantly almost by half. Freshly fried chips had a higher moisture content than parboiled fried chips. Chips of Sree Rashmi recorded the greatest score for organoleptic quality presumably due to its low acridity. Thinner chips score higher for organoleptic quality than thicker chips while parboiled chips scored higher than freshly fried chips. Evaluation of flour prepared from colocasia revealed that with increasing temperatures and drying periods moisture content decreased. The flour dried at 7SoCfor 18 hours was judged the best because it had low moisture content and good colour. The evaluation ~f secondary products prepared viz., Murukku, Wafers and Papads revealed that products made from flour of Sree Rashmi and Thamarakannan had higher organoleptic quality. Storage studies of the primary and secondary products evaluated the changes in starch, total sugars, moisture content and organoleptic quality. In case of chips while starch content did not change significantly, the total sugar and moisture content increased slightly on storage. The organoleptic quality declined on prolonged storage. Glass and PET bottles gave better storage results than LDPE bags. The moisture and total sugar content in stored flour increased more rapidly in LDPE bags than in glass and PET jars while changes in starch content were not significant. Murukku and Wafers stored in LDPE bags showed a decrease in starch content. The total sugars and moisture content of murukku increased over the period of storage in all containers, though those in LDPE bags showed the maximum increase. The murukku and wafers stored in glass and PET jars had higher organoleptic quality than those stored in LDPE bags. Pappads had a shelf life of only 30 days after which they were subject to mould attack.
  • Thumbnail Image
    ThesisItemOpen Access
    Performance of bacterial wilt tolerant tomato (Lycopersicon esculentum Mill.) genotypes under shade
    (Department of Olericulture, College of Agriculture, Vellayani, 2002) Smitha, K; KAU; Celine, V A
    An experiment on the "Performance of Bacterial wilt tolerant tomato (Lycopersicon esculentum Mill.) genotypes under shade" was conducted at the College of Agriculture, Vellayani, during 2000 - 200 I. The experiment was laid out in randomised block design with three shade levels, open, 25 and 50 per cent and replicated thrice. Artificial shade was provided using high density polyethylene shade nets. Ten bacterial wilt tolerant genotypes of tomato collected from various sources along with a susceptible check were used. The results indicated that plant height at flowering, height at harvest, internodal length, leaf length, leaf width and petiole length showed an increasing trend with increase in level of shade, while number of primary branches reduced with shade. Shading prolonged vegetative phase and delayed flowering. Flowers per cluster, percentage fruit set and number of fruits per plant were found unaffected by mild shade of 25 per cent, but under dense shade of 50 per cent, there was marked reduction in all these characters. Fruit characters like fruit length, diameter and fruit weight were found unaffected by shade Yield in open and 25 per cent shade were on par indicating that tomato plant was tolerant to mild shade. There were significant variation for yield among the genotypes. LE 45, LE 34 and LE 22 were identified as superior with tolerance to bacterial wilt and shade. These genotypes are recommended for large scale cultivation in the homesteads after proper multilocational trials. There was significant reduction 'in the incidence of tomato spotted wilt disease under shade. LE 34 and LE 44 were found least affected while LE 22 showed the highest level of incidence. Fruit borer and serpentine leaf miner infestation were also reduced under shade. LE 1, LE 2 and LE 42 recorded the lowest score against fruit borer infestation. Leaf miner infestation was least in LE 2 and LE 42 while the high yielding genotype LE 45 was affected more. Anatomical characters like stomatal density and number of vascular bundles showed a decreasing trend with increase in level of shade. Chlorophyll ~,chlorophyll Q and total chlorophyll contents increased with increase in level of shade. The shade tolerant genotypes showed higher content of chlorophyll under all shade levels. On the contrary, open condition showed maximum accumulation of proline compared to both the shade levels. Mild shade proved favourable for improving the fruit quality in tomato. There was an increase in the content of vitamin C .under 25 per cent shade level. Vitamin A content of fruits were found unaffected by mild shade of 25 per cent. But 50 per cent shade reduced both vitamin C and A contents considerably. The external appearance of the fruits was also superior under 25 per cent shade. Genotype LE 22 was superior for vitamin C content while LE 34 and LE 42 recorded the highest vitamin A content.
  • Thumbnail Image
    ThesisItemOpen Access
    Post harvest studies in adhatoda. (A.Zeylanica (Medic) & A.beddomei (Clarke))
    (Department of Processing Technology, College of Horticulture, Vellanikkara, 2002) Sujatha, M P; KAU; Jacob John, P
    An experiment was conducted in the Department of Processing Technology, College of Horticulture, Vellanikkara during 2001-2002 to evolve a suitable drying regime for adhatoda and to find out the suitable packaging materials ideal to store the dried samples and hot water extracts with minimum quality deterioration. Sun drying of the whole plant chopped into pieces was evolved as the best drying technique with respect to the quality attributes like vasicine content and alcohol as well as water soluble extracts for A. zeylanica and A. beddomei. Chopping of the whole plant helped in achieving faster drying. Roots of adhatoda also have sufficient quantity of medicinally active constituent vasicine. So uprooting the whole plant would be better than taking aerial cuttings alone. Sundried chopped pieces stored in 250 gauge polyethylene bags and powdered samples in steel containers had maximum retention of principal alkaloid vasicine after storage in room temperature for 5 months for both the species and the same samples also recorded the lowest microbial content whereas for hot water extract, glass bottles were more ideal than plastic bottles as it gave better shelf life, higher retention ofvasicine and lower microbial count. The technique thus developed can help to store the materials in a limited space for longer time without much spoilage or quality deterioration besides three times the quantity of dried whole plant could be accommodated when it is powdered and stored in rigid containers, additionally it adds convenience for the usage.
  • Thumbnail Image
    ThesisItemOpen Access
    Value addition and evaluation of nutritional quality in elephant foot yam (Amorphophallus paeoniifolius Dennst.)
    (Department of Processing Technology, College of Agriculture, Vellayani, 2002) Sini, S; KAU; Philipose, Joshua
    A study on "Value addition and evaluation of nutritional quality in elephant foot yam (Amorphophallus p aeoniifolius (Dennst))" was carried out at the Department ,of Processing Technology, College of Agriculture, Vellayani, Thiruvananthapuram during the period 1999-2001. The objective of the study was to evaluate nutritional qualities of amorphophallus cultivars, examine the potentiality of developing value added products, to assess the storage and shelf life of prepared products. The nutritional quality of corms and petioles of four cultivars ie., Sree Pad ma, Vellayani local, Pathanamthitta local and Kottarakkara local were evaluated. Corms ofPathanamthitta local had highest starch, vitamin C and protein content. Sree Padma recorded the maximum total sugar and crude fibre. Calcium oxalate content was least in the corms of Sree Padma and Pathanamthitta local. Organoleptic quality score was highest in Pathanamthitta local. In case of petioles, Pathanamthitta local had highest protein content and organoleptic ~core. Sree Padma recorded the highest total sugar content while Kottarakkara local had the maximum vitamin C and crude fibre content. Value added products like chips and traditional snack items viz., murukku, wafers and papads were prepared. Chips were prepared by two techniques ie. frying of fresh slices ,parboiling and frying. It was found that oil uptake increased with increasing thickness and parboiling was an effective method to reduce oil uptake. Oil intake was lowest in Pathanamthitta local. Moisture content increased with thickness. Freshly fried chips had higher moisture content than parboiled chips. Starch and total sugar content increased with increasing thickness. Parboiled chips had lesser total sugar content. Highest scores for organoleptic quality was recorded in chips made from Pathanamthitta local. Two mm thick chips were the most preferred while, freshly fried chips had higher organoleptic score than parboiled chips. The evaluation of flour prepared from Amorphophallus revealed that, with increasing temperatures and drying periods, moisture content decreased. Flour dried at 75°C for 18 hours was judged as the best due to low moisture content and good colour. The evaluation of secondary products viz., murukku, wafers and papads revealed that murukku and wafers prepared from the flour of Pathanamthitta local had the highest score while papads made from flour of Sree Padrna scored the highest. Storage studies of the products revealed the changes in starch, total sugars, moisture content and organoleptic quality. Starch content declined on storage while total sugar and moisture content increased slightly. Glass and PET bottles gave better storage results than LOPE bags. The moisture and total sugar content increased more rapidly in LDPE bags than glass and PET bottles during storage. Papads exhibited a shelf life of only 30 days after which they were subjected to mould attack. Organoleptic quality score was highest for all the products stored in glass bottles than PET bottles and LDPE bags.