Title of Invention

AN IMPROVED PROCESS FOR THE PREPARATION OF LITCHI(LITCHI CHINENSIS)BEVERAGE

Abstract

The invention relates to an improved process for the preparation of litchi (Litchi chinensis) beverage. In our invention, it has been observed that freezing of litchi fruits before peeling would be helpful to prevent non -enzymatic browning on storage at tropical ambient temperature. The process comprises of washing, packaging of fresh litchi fruits in LDPE bags without peeling and freezing. The frozen litchi fruits are lye peeled with hot lye solution and then neutralized by dipping in some acidulants which may be lime juice, citric acid, amla juice, tartaric acid or combination of them. Neutralized litchi fruits are then subjected for deseeding and pulping. The juice is extracted from the litchi pulp and mixed with sugar syrup containing citric acid to get the litchi beverage. The said beverage may be pasteurized at 85°C and hot filled in pre sterilized glass bottles. After, sealing with crown cork the litchi beverage may be stored at tropical ambient temperature with or without the addition of preservatives. The litchi beverage prepared by this process can be stored up to one year without any browning, discolouration or microbial spoilage. The stored litchi beverage has excellent colour, flavour, taste and overall quality.

Full Text

The present invention relates to an improved process for the preparation of litchi (Litchi chinensis) beverage. Litchi is a subtropical fruit belongs to a family Sapindaceae. Its fruit is highly prized in its fresh and preserved forms. The fruit are borne in bunches on trees that may reach a 9 -12 meters in height. When the fruit is mature, its pericarp become thin, hard and somewhat warty in texture. Depending on the variety, the pericarp may be pale green, bright red or rose coloured. An individual fruit is round to oval in shape and measures 2.5 to 4 cm in diameter. The edible portion of the fruit is a white to cream coloured translucent pulp (fleshy aril) that surrounds a glossy, brown seed. The pulp is grape - like in texture, very succulent and a aromatic and is characterized by a sweet, acid taste. The clear and aromatic squash prepared from litchi by process of this invention before using can be diluted 3 volumes with chilled water and can be relished like other fruit beverages. The litchi squash is accompanied by a excellent pleasing flavour which is very much appetizing. The non-enzymatic browning (NEB) could be prevented in litchi squash during storage at ambient temperature and shelf life of the squash could be extended up to one year without the addition of any preservative. There are few prior reports on the prevention of non-enzymatic browning of litchi squash during extraction of juice and storage at room temperature (28 - 35°C). Reference may be made to Day, HG and Sheu, MJ (1996). Prevention of lychee juice discolouration during extraction. FT (USA) Annual meeting: Book of Abstracts, p. 87 ISSN 1082 - 1236, wherein the litchi juice normally gets browning during storage which is due to the presence of polyphenyl oxidases (PRO) enzymes. Delayed extraction of peeled litchis for up to 8 hours resulted in reduction of titratable acidity from 0.06 to 0.02 % and an increase in juice pH from 5.9 to 7.0. These changes resulted in discolouration of litchi juice from milky white to light greenish yellow. Similar results were obtained when extracted litchi juices were left for up to 10 hours. HPLC analyses indicate that reduction of L - malic acid is the main reason for a reduction in titratable acidity and an increase in pH. These trends could be avoided by heating juice at 95°C for 30 sec, or offset by addition of malic acid. The main drawback of this report is that browning could not be prevented at room temperature rather than low temperature and shelf life of the litchi can not be extended at both the temperatures for more than 6 months. The main object of the present invention is to provide an improved process for the preparation of litchi (Litchi chinensis) beverage, which obviates the drawbacks as detailed above. Accordingly an improved process for the preparation of litchi (Litchi chinensis) beverage, which comprises : (a) Cleaning, washing and drying the fresh litchi fruits by known methods, (b) freezing the above litchi fruits at -20°C for 6-7 hours, (c) peeling the frozen fruits by dipping them in a hot lye solution containing NaOH 5-10% , at 85-90°C temperature, (d) neutralizing the hot lye peeled litchi fruits by steeping in 0.2 - 1.0 % acidulants solution, (e) deseeding the neutralized litchi fruits to obtain edible portion, the fleshy arils which is washed with water, (f) crushing the above fleshy arils mechanically at a speed of 500 - 1000 rpm to obtain pulp, (g) filtering the above obtained crushed pulp through fine muslin with the mesh size 200 - 300 mµ.cloth to obtain clear juice , (h) mixing sugar syrup (45°Brix) containing 1.2-1.3 % citric acid with clear juice as obtained in step (g) to get the litchi beverage & pasteurizing at 85-90°C for 5-8 minutes. In an embodiment a process the hot lye used may be sodium hydroxide solution, In an another embodiment a process the acidulant solutions used for neutralization may be citric acid, ascorbic acid, tartaric acid, sorbic acid, Indian gooseberry juice or lime juice. A process as claimed in claim (g), the sugar osmoticum may be of hot sugar syrup (45°Brix) containing 1.2 - 1.3 % acidity to get the beverage in liquid form and followed by bottling in pre-sterilized glass bottles. The litchi concentrate which has a final acidity ranging between 1.2 -1.3 % in 3 - 4 volumes of chilled or milk to get beverage in liquid form. The non - enzymatic browning (NEB) could be curtailed at ambient temperature to a considerable extent by pasteurization at 80 - 85 °C temperature. Process of the present invention involves following steps. 5 kg of fresh litchi fruits (Litchi chinensis) are cleaned off extraneous matter and soil with 20 - 30 liters of cold water (12 °C). The water from the fruit surface is removed with air drying at room temperature on big size filter paper. The litchi fruits are packed in LDPE bags and kept at low temperature (-20°C) for 6-7 hours after freezing at low temperature the litchi fruits are followed by dipping in hot lye solution at 90°C for 2 minutes (5 % NaOH) and simultaneously the skin of litchi fruits are removed by applying water force and followed by neutralized in 0.5 % citric acid solution or any other acidulant for 15 min. The pre peeled litchi fruits are deseeded and the edible portion, which known as fleshy arils are crushed in fruit mill and simultaneously filtered through muslin cloth for clear juice filtration. The clear juice is mixed with sugar syrup containing 1.2-1.3 % citric acid and 40°Brix and the mixed beverage so obtained is equilibrated to 45 °Brix with simultaneous heating at 85°C. The pre chilled beverage can be diluted to 3-4 times volume of chilled water and serve. Alternatively, the sugar mixed beverage can be preserved with or without the addition of 300 ppm of potassium metabisulphite (KMS) for more than 12 months at ambient temperature in pre sterilized glass bottles. Alternatively, the deseeded litchi fleshy arils may be crushed along with 0.2 - 0.4 % citric acid and ascorbic acid in the ratio of 1:1 to avoid browning reaction. Alternatively, the extracted clarified juice can be pasteurized at 80 - 85°C for 5 - 10 minutes to avoid browning. The following examples are given by way of illustration of the present invention and should not be construed to limit the scope of the present invention Variations and changes may be made by one skilled in the art without departing from the spirit of the invention. All parts and percentages are by weight, unless otherwise indicated. Example 1 5 kg of fresh litchi fruits (Litchi chinensis) are cleaned off extraneous matter and soil with 25 liters of cold water (12 °C). The water from the fruit surface is removed with air drying at room temperature on big size filter paper. The litchi fruits are packed in low density polyethylene (LDPE) bags and kept at low temperature (-20°C) for 8 hours after freezing at low temperature the litchi fruits are followed by dipping in hot lye (5 % NaOH i.e. 5g NaOH pellets/100 ml water) solution at 90°C temperature for 2 minutes and simultaneously the skin of litchi fruits are removed by applying water force through water suction pump and followed by neutralization in 0.5 % citric acid solution for 15 min. The pre peeled litchi fruits are deseeded and the edible portion, which is known as fleshy arils are crushed in fruit mill and simultaneously filtered through muslin cloth for clear juice. The clear juice (25 %) is mixed with sugar syrup of 40°Brix containing 1.2 % citric acid. The beverage so obtained is equilibrated to 45°Brix with simultaneous heating at 85°C temperature. The beverage yield was two liters. The pre-chilled beverage can be diluted to 3 times volume of chilled water and serve. Example 2 5 kg of fresh litchi fruits (Litchi chinensis) are cleaned off extraneous matter and soil with 25 liters of cold water (12 °C). The water from the fruit surface is removed with air drying at room temperature on big size filter paper. The litchi fruits are packed in low density polyethylene LDPE bags and kept at low temperature (-20°C) for 8 hours after freezing at low temperature the litchi fruits are followed by dipping in hot lye (5 % NaOH i.e. 5g NaOH pellets/100 ml water) solution at 90°C temperature for 2 minutes and simultaneously the skin of litchi fruits are removed by applying water force through water suction pump and followed by neutralization in 0.5 % citric acid solution for 15 min. The pre peeled litchi fruits are deseeded and the edible portion, which is known as fleshy arils are crushed in fruit mill with the addition of 0.2 % citric acid with ascorbic acid in the ratio of 1:1 to avoid browning reaction and simultaneously filtered through muslin cloth for clear juice. The clear juice is mixed with sugar syrup of 40°Brix containing 1.2 % citric acid. The litchi beverage so obtained is equilibrated to 45 °Brix with simultaneous heating at 85°C temperature. The beverage yield was two liters. The pre-chilled beverage can be diluted to 3 times volume of pre-chilled water and serve. Example 3 5 kg of fresh litchi fruits (Litchi chinensis) are cleaned off extraneous matter and soil with 25 liters of cold water (12 °C). The water from the fruit surface is removed with air drying at room temperature on big size filter paper. The litchi fruits are packed in low density polyethylene LDPE bags and kept at low temperature (-20°C) for 8 hours after freezing at low temperature the litchi fruits are followed by dipping in hot lye (5 % NaOH i.e. 5g NaOH pellets/100 ml water) solution at 90°C temperature for 2 minutes and simultaneously the skin of litchi fruits are removed b> applying water force through water suction pump and followed by neutralization in 0.5 % lime juice solution containing Indian gooseberry juice (1:1) 15 minutes. The pre peeled litchi fruits are deseeded and the edible portion, which is known as fleshy arils are crushed in fruit mill with the addition of 0.5% lime juice containing Indian gooseberry juice (1:1 ratio) and simultaneously filtered through muslin cloth for clear juice. The clear juice is mixed with sugar syrup of 40°Brix containing 1.2 % citric acid. The litchi beverage so obtained is equilibrated to 45°Brix with simultaneous heating at 85°C temperature and after cooling the 300ppm potassium metabisulphite can be added to avoid the browning reaction which is optional for long term storage. The beverage yield was two liters. The pre-chilled beverage can be diluted to 3 times volume of chilled water and serve. The main advantages of the present invention are: 1). The litchi beverage is devoid of non - enzymatic browning which is undesirable in the beverage. 2). The stability of the litchi beverage is more than 12 months at ambient temperature. 3). The beverage can be preserved with or without the addition of preservative (KMS). 4). The cloudiness in the beverage is not possible due to inactivation of the enzymes during lye peeling. 5) The litchi beverage prepared by this method is devoid of browning so the marketability of the beverage may increased to a considerable extent and to meet the consumer's demand. We claim: 1. An improved process for the preparation of litchi (Litchi chinensis) beverage, which comprises : a) Cleaning, washing and drying the fresh litchi fruits by known methods, b) freezing the above litchi fruits at -20°C for 6-7 hours, c) peeling the frozen fruits by dipping them in a hot lye solution containing NaOH 5-10% , at 85-90°C temperature, d) neutralizing the hot lye peeled litchi fruits by steeping in 0.2 - 1.0 % acidulants solution, e) deseeding the neutralized litchi fruits to obtain edible portion, the fleshy arils which is washed with water, f) crushing the above fleshy arils mechanically at a speed of 500 - 1000 rpm to obtain pulp, g) filtering the above obtained crushed pulp through fine muslin with the mesh size 200 - 300 mµ.cloth to obtain clear juice , h) mixing sugar syrup (45°Brix) containing 1.2-1.3 % citric acid with clear juice as obtained in step (g) to get the litchi beverage & pasteurizing at 85-90°C for 5-8 minutes. 2. A process as claimed in claim 1, wherein the acidulant solutions used for neutralization is citric acid, ascorbic acid, tartaric acid, sorbic acid, Indian gooseberry juice or lime juice, 3. An improved process for the preparation of litchi (Litchi chinensis) beverage, substantially as described herein with reference to the examples.

Documents:

432-DEL-2003-Abstract-(03-12-2008).pdf

432-del-2003-abstract.pdf

432-DEL-2003-Claims-(03-12-2008).pdf

432-DEL-2003-Claims-(10-12-2008).pdf

432-del-2003-claims.pdf

432-del-2003-complete specifiction (granted).pdf

432-DEL-2003-Correspondence-Others-(03-12-2008).pdf

432-DEL-2003-Correspondence-Others-(10-12-2008).pdf

432-del-2003-correspondence-others.pdf

432-del-2003-correspondence-po.pdf

432-DEL-2003-Description (Complete)-(03-12-2008).pdf

432-DEL-2003-Description (Complete)-(10-12-2008).pdf

432-del-2003-description (complete).pdf

432-del-2003-form-1.pdf

432-del-2003-form-18.pdf

432-del-2003-form-2.pdf

432-DEL-2003-Form-3-(03-12-2008).pdf

432-del-2003-form-3.pdf