INDIVIDUAL SHRINK WRAPPING OF FRUITS AND VEGETABLES
Authors: K. Rama Krishna and G. Gajanan
Division of Food Science & Postharvest Technology, IARI, New Delhi-110012.
E-mail: ramakrishna.karri001@gmail.com




Introduction

Fruits and vegetables due to their high moisture content and respiration activity tend to degradation after harvest from their source plant. The water loss by transpiration from living produce causes not the only shrinkage, drying and softening of the fruit, but also triggers the change from juvenile hormonal balance to a senescent one, leading to accelerated deterioration of the produce. Individual seal packaging or shrink wrapping of fresh fruits and vegetables greatly reduces weight loss by reducing the transpiration rate and maintain fruit firmness.

Individual Seal Packaging

Individual seal packaging, which may be considered as Modified Atmosphere Packaging (MAP) for individual fruit, involves sealing of fruit in a flexible film followed by heat shrinking to adhere the film tightly around the produce. In individual seal packaging the film (without ventilation holes) is shrink-wrapped tightly around each piece of produce to form a tight, smooth package of each fruit making it as another layer of protective cuticle.

Advantages of Individual shrink wrapping

  • Reduction of weight loss.
  • Decay control.
  • Reducing chilling injury.
  • Reducing blemishes.
  • Delaying ripening and fruit senescence.
  • Maintenance of firmness.
  • Reduction of deformation.
  • Reduction of decay from secondary infection.
  • Delay in colour development and senescence.
  • Improved sanitation in handling the produce from packing to consumption.
  • Creation of modified atmosphere around the fruit thereby extension of storage life.
  • Elimination of the need to maintain high humidity during storage /transit.
  • Possible reduction of refrigeration requirement.
  • Extending the market season.
  • Consumer appeal, in that the whole surface of the produce can be examined prior to purchase.
  • Variety and brand identification.

Flow chart for Individual Seal Packaging

Freshly harvested fruits/vegetables

↓

Sort/Grade

↓

Trim the stalks

↓

Wash/Disinfect

↓

Surface dry

↓

Loose pack individually

↓

Pass through shrink tunnel (300-350°F) for 8 to 10 sec

↓

Collect and Master pack


Disadvantages

  1. Acceleration of decay in some cases
  2. Development of off flavours
  3. Magnification of defects on produce
  4. Cost of film and application
Some of the fruits and vegetables which can be shrink wrapped are given in the table below.

S.no Fruits Vegetables
1 Oranges and Lime Capsicum
2 mandarins Cabbage
3 Pomegranate Cucumber
4 Apple Zucchini
5 Guava Tomato
6 Water melon and Musk melon
7 plums
8 Mango
Individual shrink wrapping could be used effectively for reduction of weight loss and maintenance of freshness of high-value fruits and vegetables. For shorter periods, shrink wrapping may enable storage without refrigeration with a possible extension of storage life at lower cost than by conventional means. The money gained by reducing the weight loss to a greater extent will overcome the cost of film application and thus would be economical. Seal packing would also help to substitute air transport by marine shipment (long term transport) for some commodities



About Author / Additional Info:
Ph.D. Scholar, Division of Food Science and Postharvest Technology