Title of Invention	AN IMPROVED PROCESS FOR OAK TASAR (ANTHERAEA PROYLEI J.) COCOON COOKING USING PINEAPPLE EXTRACT.
Abstract	This invention relates to an improved process for cooking of oak tasar {Antheraea proylei J) cocoon comprising the steps of subjecting the cocoons to the 45 min pressure cooking in distilled water at 15 lbs/so inch. Soaking the cooked cocoons in pineapple extract with 0.125% soda at 60C for 30 mins.

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FIELD OF INVENTION This invention relates to an improved process for oak tasar (Antheraea proylei J.) cocoon cooking using pineapple extract. BACKGROUND OF INVENTION Unlike the mulberry (Bombyx mori L.) cocoons, the tasar (Antheraea proylei J.) cocoons cannot be softened satisfactorily by boiling in plain water. As such more drastic boiling off techniques have to be adopted. In the traditional method, the tasar cocoons, including the oak tasar cocoons, are cooked in earthen pitcher by adding a quantity of washing soda for 4-6 hrs. This crude method gives only 40-50% cooking efficiency and reduces cohension of the silk filaments essential for yarn reeling, and hence this method is very uneconomical and crude. Alternative to the traditional method, various chemical methods have been tried by research stations all over India and abroad to improve the tasar cocoon cooking method. These methods often use more than one of the chemicals including soap, soda, sodium hydroxide, hydrochloric acid, sodium tetraborate, sodium silicate, alum, formalin, sodium laurylsulphate, non-ionic surfactant, hydrogen peroxide and organic amine. These methods, however, weaken the silk yarn, raise naps, reduce lustre, and reduce smoothness and thus present an obstacle to the tasasr silk reeling and weaving efficiencies and woven fabric quality. Besides, the strong chemicals such as hydrogen peroxide are toxic, may cause irritations to the workers of silk industry, and may cause affluent problems. On the other hand, the methods of oak tasar cocoon cooking using proteolytic enzymes such as Biopril-50 have been found to be effective while conquering most of the defects arising out of the chemical boiling off techniques. In a currently adopted enzymatic method based on the commercial protease preparation, the oak tasar cocoons are wrapped in a coarse cotton cloth, then subjected to 10 min boiling followed by one hour steaming at 15 lbs/sq inch pressure, and then soaked in 0.05% of the commercial protease preparation known by the trade name Biopril-50 (Anil Starch Pvt. Ltd., Ahmedabad), for 18-22 hrs at 60°C initially and thereafter at room temperature. The cocoons are then taken out, washed repeatedly to remove the associated brown colour and proteolytic activity. The cocoons are then freed from the cloth wrapper, semi-dried on blotting papers, deflossed, and then reeled. The traditional and chemical methods of oak tasar cocoons cooking have their own drawbacks as mentioned above. A better alternative to these methods has been enzymatic method using commercial protease preparations. However, this method is also not without certain drawbacks. For example, the oak tasar cocoon cooking procedure based on the commercial enzyme Biopril-50 known in the art are complicated, time consuming, and limited by rare availability of the enzyme preparations. As such, the common tasar silk reelers and weavers do not readily adopt these enzymatic methods. Moreover, due to prolonged exposure (18-24 hr) of the tasar cocoons to the commercial enzymes during the cooking method, more than desired amount of sericin is lost resulting in poor agglutination of silk filaments during yarn reeling. Consequently, the loosely held baves get broken during weaving process and also crease up to form unsightly fuzz on the surface of the yarn or finished fabric. OBJECTS OF THE INVENTION An object of this invention is to propose an improved process for oak tasar (Antheraea proylei J) cocoon cooking using pineapple extract. Another object of this invention is to propose an improved process for oak tasar {Antheraea proylei J) cocoon using pineapple extract and wherein the initial pretreatment of the cocoon is simple. Yet another object of this invention is to propose an improved process for oak tasar (Antheraea proylei J) cocoon cooking using pineapple extract and wherein the loss of sericin is reduced. Still another object of this invention is to propose an improved process for oak tasar (Antheraea proylei J) cocoon using pineapple extract and wherein the period required for the cooking step is reduced. A further object of his invention is to propose an improved process for oak tasar (Antheraea proylei J) cocoon cooking using pineapple extract, which is efficient. Brief description of the accompanying drawings- Fig. 1: The samples of oak'tasar silk filaments related from oak tasar (Antheraea proylei J) cocoons cooked by the novel pineapple extract method and the currently adopted Biopril-50 method. See the text for details of the different cocoon cooking procedures. Sample 1: silk filaments obtained from cocoons cooked using pineapple extract in presence of 0.125% soda at 60C; Sample 2: silk filaments obtained from cocoons cooked using Biopril-50; Sample 3: silk filaments obtained from cocoons cooked using pineapple extract alone at 60°C Fig 2: The scanning electron photomicrographs of oak tasar silk filaments reeled from oak tasar (Antheraea proylei J) cocoons cooked by the novel pineapple extract method (A) and the Biopril-50 method (B). Fig 3: The samples of oak tasar silk yarns reeled from oak tasar (Antheraea proylei J) cocoons cooked by the novel pineapple extract method and the currently adopted Biopril-50 method. See the text for details of the two different cocoon cooking procedures. Sample 1: silk yarns obtained from cocoons cooked using pineapple extract in presence of 0.125% soda at room temperature; Sample 2: silk yarns obtained from cocoons cooked suing pineapple extract alone at room pemperature; Sample 3: silk yarns obtained from cocoons cooked using pineapple extract in presence of 0.125% soda at 60°C; SampleS: silk yarns obtained form cocoons using Biopril-50. DESCRIPTION OF THE INVENTION According to this invention there is provided an improved process for cooking of oak tasar (Antheraea proylei J) cocoon comprising in the step of: a) Subjecting the cocoons to the step of pressure cooking in distilled water. b) Soaking the cooked cocoons in a pineapple extract with soda. In accordance with this invention, the fruit extract of pipeapple Ananas comosus (L.) Merr. Cv. Queen, containing a mixture of cysteine proteases mainly the fruit bromelain (EC 3.4.22.33) was found to be suitable for use in oak tasar cocoon cooking. The cocoons subjected to 30-45 min initial pressure cooking are completely softeed by soaking for example in just 30 min in the pineapple extract in the presence of a small amount of soda at 60C at which the proteolytic activity of the pineapple extract is optimum. The cocoons cooked by such a method were successfully reeled by using either epprouvette machine (single filament reeling) or CTR&TI pedal reeling cum twisting machine (yarn reeling). The oak tasar cocoon cooking method of he present invention has been found to be of better alternative to the existing traditional or enzymatic method, and it can be readily accessible to common tasar silk reelers and weavers. The silk filaments or yarns reeled from oak tasar cocoons cooked by the present novel cooking method have been found to be either technologically better or comparable to those reeled from the cocoons cooked by the Biopril-50 method. EXAMPLE Good fresh or preserved hot air stifled oak tasar cocoons were wrapped in a coarse cotton cloth and then subjected to 45 min pressure cooking in distilled water at 15 lbs/sq inch pressure in a pressure cooker. The cocoons still in the cloth wrapper were then transferred to and Soaked in the pineapple extract with 0.125% soda at 60 °C for 30 min after the cooking, the cocoons with the wrapper were taken out from the cooking medium and washed with tap water to remove the associated brown colour and proteolytic activity. The cocoons were then freed from the wrapper, semi-dried on blotting papers, deflossed-and then reeled oh an epprouvette machine for getting single silk filaments or on a modified CTR&TI pedal reeling cum twisting machine for getting silk yarn. He single silk filaments were subjected to tensile and elongation tests at 25°C and 64% humidity using Instron Tensile Strength Tester 6021 installed in the Textile Testing Laboratory, Central Silk Technological Research Institute, Central Silk Board, Ministry of Textile (Government of India), Bangalore, India. The silk filaments were also subjected to scanning electron microscopic examination and photography using scanning electron microscopic model stereoscan 360 of Cambridge instruments installed in the SEM laboratory, Department of Textile Technology, Indian Institute of Technology, New Delhi, India. The oak tasar cocoon cooking method of the present invention was assessed by performing single silk filament reeling and the results obtained are compared with those of the Biopril-50 method already in vogue in Table 1. The resulting silk filaments reeled from the oak tasar cocoons cooked by the pineapple extract and Biopril-50 methods are shown in Fig.l of the accompanying drawings. Table 1: Comparison of the results of the novel oak tasar {Antheraea proylei J.) cocoon cooking method based on pineapple extract developed in the present -invention with those of the existing method using the commercial enzyme Biopril-50* (Table Removed) * Each value in the table is an average of fifteen replications. ** Sonwalker and Jolly (1985) *** Experimental conditions, under which tenacity (g/D) and elongation % were determined, were humidity - 64%, temperature - 25°C, number of repetitions - 20 taking reeled single filaments from outer, middle and inner parts of the cocoon. As compared to the Biopril-50 method, the pineapple extract procedure was found to show (i) more or less comparable single filament reeling performance with respect to filament length, recovery %, denier and elongation'%, (ii) higher reeling performance with respect to reelability % (due to lesser number of ends feeding per cocoon), NBFL and tenacity; (iii) much shorter overall duration of cocoon cooking (less than 2 hr as against more than 21-25 hr for the Biopril-50 method), and (iv) greater simplicity and economy of the new oak tasar cocoon cooking procedure which might facilitate more accessibility of the pineapple extract method to common silk reelers and weavers. When the silk filament sample was subjected to scanning electron microscopy, it was found to,be equally as clean as the silk filament sample obtained by Biopril-50 method (Fig 2). The silk filaments were found to be sufficiently free from the silk gum sericin suitable for optimum yarn reeling, and no surface damage characterized by rupture/fibrillation of filament was seen due to excessive removal of sericin. The preserved oak tasar cocoons cooked by the procedure of pineapple extract method developed in the present invention were also subjected to the method of mass (yarn) reeling performed on a modified CTR&TI pedal reeling cum twisting machine in the Regional Tasar Research Station, Imphal and the results were compared those obtained by adopting the cocoon cooking procedure of Biopril-50 method. The comparison is shown in Table 2. The resulting silk yarns reeled from the oak tasar cocoons cooked by the pineapple extract and Biopril-50 methods are shown in Fig. 3, Table 2: Comparison between the pineapple extract method and the Biopril-50 method of oak tasar cocoon cooking with respect to their performance on mass reeling on a modified CTR&TI pedal reeling cum twisting machine* (Table Removed) * Each value in the table is an average of two replications of fifty cocoons each. The mass reeling performance obtained with the preserved oak tasar cocoons subjected to the novel cooking method based on pineapple extract was found to be good and it was characterized by cooking efficiency of 100%, raw silk recovery of 66.7%, yield per 1000 cocoons of 400 g, production per 8 hr per reeler of 200 g and renditta of 2500 cocoons. When compared with Biopril-50 method, these yarn reeling parameters were either better or comparable. The tenacity and elongation % were slightly lower than that of the Biopril-50 method. However, the time taken by the soaking step of the pineapple extract cocoon cooking procedure was just 30 min thereby making overall duration of the procedure much less (less than 2 hr) as compared to that of the cocoon cooking procedure of the Biopril-50 method (more than 21-25 hr) We Claim 1. An improved process for cooking of oak tasar (Antheraea proylei J) cocoon comprising the steps of :- a) subjecting the cocoons to the 45 min pressure cooking in distilled water at 15 lbs/so inch b) Soaking the cooked cocoons in pineapple extract with 0.125% soda at 60C for 30 mins. 2. An improved process for cooking of oak tasar cocoon as claimed in claim 1 wherein the pineapple extract contains cysteine protease mainly the fruit bromelain. 3. An improved process for cooking of oak Tasar Cocoon substantially as herein described and illustrated.

Documents:

960-DEL-2004-Abstract-(09-06-2009).pdf

960-del-2004-abstract.pdf

960-DEL-2004-Claims-(09-06-2009).pdf

960-del-2004-claims.pdf

960-DEL-2004-Correspondence-Others-(09-06-2009).pdf

960-DEL-2004-Correspondence-Others-(11-08-2009).pdf

960-del-2004-correspondence-others.pdf

960-del-2004-correspondence-po.pdf

960-DEL-2004-Description (Complete)-(09-06-2009).pdf

960-del-2004-description (complete).pdf

960-DEL-2004-Drawings-(09-06-2009).pdf

960-del-2004-drawings.pdf

960-DEL-2004-Form-1-(09-06-2009).pdf

960-del-2004-form-1.pdf

960-del-2004-form-18.pdf

960-DEL-2004-Form-2-(09-06-2009).pdf

960-del-2004-form-2.pdf

960-DEL-2004-Form-3-(09-06-2009).pdf

960-DEL-2004-GPA-(11-08-2009).pdf

960-DEL-2004-Others-Documents-(09-06-2009).pdf