ABSTRACT (Makwana Sachin)
An experiment was carried out to study effect of pre-cooling on post harvest life of Sapota (Manilkara achras (Mill) Fosberg) cv. Kalipatti at the Post Graduate Laboratory of the Department of Horticulture, Junagadh Agricultural University, Junagadh during the year 2010. The various pre-cooling treatments viz., control, pre-cooling at 6ºC, pre-cooling at 8°C, pre-cooling at 10°C and pre-cooling at 12°C for 2 hours, 5 hours and 8 hours respectively with Completely Randomized Design with three repetition having total thirteen treatments. The results of the study indicated that mango fruits treated with different pre-cooling treatment showed lower and slower rate in physical and chemical changes than control fruits. The fruits treated with pre-cooling at 8ºC for 8 hr proved to be most effective with respect to more number of days taken to ripe, longer shelf life, lower percentage of spoilage and higher percentage of marketable fruits. Lower physiological loss in weight and higher firmness of fruits. The treatment was also promising for slower increase in TSS, reducing sugar and total sugar, while slower decrease in ascorbic acid and acidity during storage. The organoleptic rating with regard to colour, taste and overall acceptability was also found significantly higher in pre-cooling at 8ºC for 8 hr treated fruits.
Sapota (Manilkara achras (Mill) Fosberg) is a tropical fruit, belongs to family Sapotaceae and is a native of Mexico and Central America. In India, the sapota crop is mainly cultivated for its fruits. The mature fruits are also used for making mixed jams and they provide a valuable source of raw material for the manufacture of industrial glucose, pectin and natural fruit jellies. They are also canned as slices. In India, sapota is cultivated in many states viz. Karnataka, Andhra Pradesh, Tamil Nadu, Gujarat, Maharashtra etc. In Gujarat, it occupies an area of 27.4 thousand ha with a production of 272.6 lakh tones in 2009-10 (Anon., 2010). Sapota is an important fruit of tropical and subtropical region of the world. Sapota fruit comes under climacteric fruit category and it is very sensitive to cold storage (Laxminarayana, 1980).
The shelf life of sapota fruit is very short (2-3 days). After harvesting, if not handled properly, it becomes over mature within a day or two days at ambient temperature. The post harvest handling of the produce resulting in 20 to 30 per cent post harvest losses in fruits. The fruit is nutritious and fetches good returns. It suffers from a very poor shelf life associated with a rapid ripening in tropical atmosphere. The post harvest losses are high in tropical country like India range between 25 to 30 %. Therefore, there is a need to regulate it's ripening so as to improve its shelf life. For that purpose proper post harvest handling or operation must be required. Out of that pre-cooling is one of the primary post harvest operation. The main aim of pre-cooling is to remove the felid heat of the fruits and increase self life. So experiment was undertaken effect of study the effect of pre-cooling temperature and time ripening and quality bevariour of chiku fruits.
MATERIALS AND METHODS
The healthy, uniform in size and shape, free from any bruising and mechanical injured fruits of chiku cv. Kalipatti was selected and cleaned by washing under cold tap water then wiped with muslin cloth. Initial weight and girth of fruits were recorded and placed in different carats and were kept in pre-cooling chamber for different temperature (6, 8, 10 and 12 °C) and time (2, 5 and 8 hours) for pre- cooling. An experiment was conducted at the Post Graduate Laboratory of the Department of Horticulture, Junagadh Agricultural University, Junagadh during the year 2010 with Completely Randomized Design with three repetition having total thirteen treatments. After treatment fruits were kept in carats under open condition at room temperature (25 to 28°C). Two fruits from each repetition were randomly selected at a time and used for bio-chemical analysis as well as organoleptic test. The organoleptic evaluation for assessing the fruit colour, pulp colour, taste and overall acceptability was done by a panel of five judges by using 10 points scale system. Firmness of fruits was recorded by using Texture Analyser TA-X T2i, which measure firmness in kg. Texture Analyzer measure force in compression, probe having 5 mm diameter were used for measuring firmness. The Analysis was done at five days interval and all the observation were recorded till the fruits were over ripe.