Title of Invention

A BIOPRESERVATIVE COATING TO EXTEND SHELF LIFE OF TOMATOES AND A PROCESS FOR PREPARATION THEREOF

Abstract

This invention relates to a biopreservative coating to extend the shelf life of tomatoes comprising of 4-6% w/v carnauba wax, 4-6% w/v casein, 4-6% w/v of an antioxidant such as turmeric powder, 180-205 ppm preferably 195-200 ppm potassium metabisulphite and 800-1500 ppm preferably 1000-1200 ppm nisin and also this invention relates to a process for the preparation of a biopreservative coating to extend shelf life of tomatoes as claimed in claim 1, comprising of the step of preparing emulsion by dissolving 4-6% w/v of carnauba wax in hot water at a temperature of 80-95°C preferably 90 to 95°C for 1-2 hours, then adding 4-6% w/v of casein and 4-6% w/v of turmeric powder and making up the volume of the mixture to for example 10 times of the initial volume, blending it by heating at 85 to 95°C for about 12 to 16 hours to form an emulsion and then cooling the said emulsion to 25 to 35°C and adding 180-205 ppm preferably 195-200 ppm of potassium metabisulphite then storing the said emulsion in a refrigerator.

Full Text

FIELD OF INVENTION 'I'his invention relates to a biopreservative coating and a process for its preparation to extend the shelf life of tomatoes (Lycopercicum esculentum) by controlling growth of undesirable microorganisms. PRIOR ART Tomatoes are available in the season for only a limited period of time, and they are highly perishable vegetable. They are fleshy and highly nutritious in fresh form as they contain antioxidant like Lycopene and are rich in fiber and vitamin C. Vitamin C is known to reduce the risk of cancer and lycopene among the carotenoids has potentially beneficial biological activity in addition to its traditional role as vitamin A precursor. Lycopene is an important antioxidant and has the ability to quench singlet oxygen and it has been shown to reduce growth of mammary cancer cells and HI -6 promyelocytic leukemia cells. Maximum spoilage of the tomatoes is due to poor handling, improper storage facilities and growth of microorganisms because of high moisture content. The tomatoes have a high respiration rate which leads to shriveling and potential water loss. The deterioration leads to organoleptic changes, destruction of vitamin-C as well as lycopene pigments and makes the product less appealing and unfit for consumption. One of the known process for preserving orange and lemon, practiced in China during 12th and 13th century, was by dipping them in wax. In US also since 1930s hot melt paraffin wax has been used for coating citrus fruits. The main disadvantage of using wax as preservative coating is that it cannot be digested in the gastrointestinal system. .Another disadvantage of the above known coating is that the toxicology studies of the hydrocarbons has not been cleared as yet. Yet another disadvantage of the above known coating is that it is not suitable for all the fruits and vegetables specially those having soft skin like the tomatoes. Still another disadvantage of the above known coating is that it is not liked bv the consumers because of the undesirable smell. Another method for coating fresh fruits and vegetables as reported by Kaplan is by using camauba wax and oil in water emulsions. The main disadvantage of using carnauba wax and oil in water emulsions as preservative coating is the development of rancidity because of the ttlend being oil based. Another disadvantage of the above known coating is that the dust sticks on the surface of vegetables, leading to a galaxy of microorganisms and cross contaminating the surface of the vegetables. Yet another disadvantage of the above known coating is that it does not control surface microorganisms as well as pathogens. Yet another antimicrobial edible packaging based on cellulose ether, fatty acids and nisin has been found to inhibit pathogens like Listena innociui and Staphylococcus aitreus. 'I'he main limitation of using above edible coating is that the process is time consuming as the drying of edible packing films takes a long time. /Vnother disadvantage of the above known coating process is that it requires specific devices for mixing, preparing the films and then drying the films. Yet another disadvantage of the above known coating process is that it is costly and requires skilled and technically qualified workers. ()ne more way of preserving tomatoes is by making puree, pickle or chutne> /sauce. The main disadvantage of preserving tomatoes in the form of puree, pickle or chutney/sauce etc. is that it requires elaborate processing unit and the tomatoes are not stored as such like a vegetable. Therefore, there was a need to develop an edible biopreservative coating which is easily digested, easy to apply in field area, is cost effecthe and extends the shelf life of tomatoes at ambient as well as cold temperature, which are otherwise available for a very shoit period of i/me. OBJECTS OF THE INVENTION The main object of the present invention is to provide a biopreservative coating and a process for its preparation to extend the shelf life of tomatoes (Lycopercicum esculentum). Another object of the present invention is to provide a biopreservative coating and a process for its preparation to extend the shelf life of tomatoes at ambient temperature for 18 days and at 5°C for 45 days. Yet another object of the present invention is to provide a biopreservative coating and a process for its preparation to extend the shelf life of tomatoes wherein non toxic natural biopreservatives are used for the coating. Still another object of the present invention is to provide a biopreservative coating which is simple to apply and can be used by an unskilled person. Further object of the present invention is to provide a biopreservative coating which can be easily used in field areas. Still further object of the present invention is to provide a biopreservative coating which can be easily digested by the human gastrointestinal system. Yet further object of the present invention is to provide a biopreservative coating and a process for its preparation to extend the shelf life of tomatoes which is relatively cheap.DETAILED DESCRIPTION OF THE PROCESS According to this invention there is provided a biopreservative coating to extend the shelf life of tomatoes comprising of 4-6% w/v carnauba wax, 4-6% w/v casein, 4-6% w/v of an antioxidant such as turmeric powder, 180-205 ppm preferably 195-200 ppm potassium metabisulphite and 800-1500 ppm preferably 1000-1200 ppm nisin. Further according to this invention there is provided a process for the preparation of a biopreservative coating to extend shelf life of tomatoes as claimed in claim 1, comprising of the step of preparing emulsion by dissolving 4-6% w/v of carnauba wax in hot water at a temperature of 80-95°C preferably 90 to 95°C for 1-2 hours, then adding 4-6% w/v of casein and 4-6% w/v of turmeric powder and making up the volume of the mixture to for example 10 times of the initial volume, blending it by heating at 85 to 95°C for about 12 to 16 hours to form an emulsion and then cooling the said emulsion to 25 to 35°C and adding 180-205 ppm preferably 195-200 ppm of potassium metabisulphite then storing the said emulsion in a refrigerator. In accordance with the present invention a biopreservative coating to extend the shelf life of tomatoes and a process for its preparation has been provided. The biopreservative coating comprising of carnauba wax, casein, turmeric powder, potassium metabisulphite and nisin which is a 34 amino acid peptide having a mol. wt. of 3500 deltons, is prepared by the following steps: a) Preparing the emulsion 4-6% w/v preferably 5% w/v of carnauba wax is soaked in hot water at a temperature of 80 to 95°C preferably 90 to 95°C for 1-2 hours, till it completely dissolved. To this dissolved carnauba wax, 4-6% w/v preferably 5% w/v of casein and 4-6% w/v preferably 5% w/v of an antioxidant preferably turmeric powder is added. Make up the volume of the mixture to 10 times of the initial volume. The mixture is then blended by heating over a heating mantle at 85 to 95°C for about 12 to 16 hours to form an emulsion. The emulsion is then cooled to 25 to 35°C. 180-205 ppm preferably 195-200 ppm of potassium metabisulphite is then added to the emulsion which is stored in a refrigerator as stock solution. b) Surface sanitizing the tomatoes Tomatoes which are semi ripened and preferably of same size are sorted out and washed well in tap water and then in 100-150 ppm chlorine solution. Then they are washed in 0.1-0.2% potassium permanganate solution to remove the surface microflora and soil flora. These washed tomatoes are then surface dried at 25-35°C. c) Coating of tomatoes The stock solution prepared in step a) is diluted with water and a 5 to 12% preferably 10% solution is made. 800-1500 ppm preferably 1000-1200 ppm of nisin is then added to make a working solution of the biopreservative coating. The washed and surface dried tomatoes from step b) are dipped for about 2 minutes in the biopreservative coating working solution. The tomatoes are then surface dried at 25-35°C in a clean environment to avoid surface condensation of moisture and microbial contamination. They are then packed in perforated polythene pouches. 'I 'his invention will now be illustrated with a working example, which is intended to be typical example to explain the technique of the presenf invention and is not intended to be taken restrictively to imply any limitation to the scope of the present invention. WORKING EXAMPLE of Carnauba wax was soaked in hot water at a temperature of 95°C for 1 hour, till it was completely dissolved. To this dissolved camauba wax, 50g of casein and 50g of turmeric powder was added. Made up the volume of the mixture to 1000 ml. The mixture was then blended by heating over a heating mantle at 95°C for about 16 hours to make an emulsion. The emulsion was then cooled to about 25 - 35°C. 200 ppm of potassium metabisulphite was then added to the emulsion which was stored in a refrigerator as stock solution. kg semi ripened tomatoes of same size were sorted out and washed well in tap water and then in 100 ppm chlorine solution. They were then washed in 0.1% potassium permanganate solution to remove the surface micro flora and soil flora. The washed tomatoes were surface dried at 25 -35°C. The stock solution was diluted with water and a 10 % solution was made. 1 000 ppm of nisin was then added to make a working solution of the biopreservative coating. The tomatoes were then dipped for 2 minutes in the biopreservative coating solution. The tomatoes were again surface dried at 25 - 35°C in a clean environment to avoid surface condensation of moistuie and microbial contamination and then packed in perforated polythrne pouches. It is to be understood that the process of the present invention is suscepuble to modifications, changes, adaptations by those skilled in the ait. Such modifications, changes, adaptations are intended to be within the scope o'f the present invention which is further set forth under the following claims. WE CLAIM; 1. A biopreservative coating to extend the shelf life of tomatoes comprising of 4-6% w/v carnaiiba wax, 4-6% w/v casein, 4-6% w/v of an antioxidant such as turmeric powder, 180-205 ppm preferably 195-200 ppm potassium metabisulphite and 800-1500 ppm preferably 1000-1200 ppm nisin. 2. A process for the preparation of a biopreservative coating to extend shelf life of tomatoes as claimed in claim 1, comprising of the step of preparing emulsion by dissolving 4-6% w/v of carnauba wax in hot. water at a temperature of 80-95°C preferably 90 to 95°C for 1-2 hours, then adding 4-6% w/v of casein and 4-6% w/v of turmeric powder and making up the volume of the mixture to for example 10 times of the initial volume, blending it by heating at 85 to 95°C for about 12 to 16 hours to form an emulsion and then cooling the said emulsion to 25 to 35°C and adding 180-205 ppm preferably 195-200 ppm of potassium metabisulphite then storing the said emulsion in a refrigerator. 3. A biopreservative coating and a process for its preparation substantially as described and exemplified herein.

Documents:

2252-del-2004-Abstract-(19-03-2010).pdf

2252-del-2004-abstract.pdf

2252-del-2004-Claims-(19-03-2010).pdf

2252-del-2004-claims.pdf

2252-del-2004-Correspondence-Others-(19-03-2010).pdf

2252-del-2004-correspondence-others.pdf

2252-del-2004-correspondence-po.pdf

2252-del-2004-Description (Complete) -(19-03-2010).pdf

2252-del-2004-description (complete).pdf

2252-del-2004-form-1.pdf

2252-del-2004-form-18.pdf

2252-del-2004-form-2.pdf

2252-del-2004-GPA-(19-03-2010).pdf