ILIP’S JOINT RESEARCH WITH THE UNIVERSITY OF BOLOGNA: HEAT- SEALED PUNNETS OFFERS ADVANTAGES FOR STRAWBERRIES

The company from Bologna maintains its commitment for more awareness regarding the role played by packaging in the reduction of food waste. The shelf life of strawberries requires refrigeration and closed r-PET punnets: heat-sealed punnets are more efficient than punnets with lids in terms of reducing the weight loss of the fruit.

BOLOGNA (2nd May 2013) – Proper storage and better shelf life of strawberries require the use of refrigerated environments, but they are not enough. Packaging closure plays a fundamental role, and heat-sealed punnets are more efficient than those with lids in terms of reducing the daily loss of weight.

These are the results of the research commissioned by ILIP, one of the main European manufacturers of thermoformed plastic packaging for food, and carried out by the Department of Agricultural Sciences of the University of Bologna with the cooperation of the company Martorano 5 of Cesena. The analysis was performed on a sample of Monterey remontant strawberries and evaluated the effect of three factors (type of packaging, pad and storage temperature) on the shelf life and the quality of the fruit.

The three types of packaging were r-PET punnets ILIP B22PET58 with and without lid and ILIP B40PET85, heat-sealed with non-perforated PET top film. Once packaged in the three types of packaging, the strawberries were stored for two days in a ventilated cold room and were then split in two groups: the first stored under refrigeration for 7 days at 4° C (plus 2 days at 23° C) and the second at room temperature (23° C) for 2 days.

The following parameters were measured before and after packaging and the storage period: pulp consistency, refractometric dry residue (°Brix), level of acidity of the juice, colour and weight reduction. The results showed that both refrigeration and the type of punnet play fundamental roles in maintaining the quality of the fruit for longer, limiting dehydration and reducing rotting.

From among the packaging systems, the heat-sealed punnets proved to be more efficient than the punnets with lids in terms of weight maintenance: they showed a weight reduction of 1.4 g per day against 3.6 g in the refrigerated scenario and with absorbing pad. Heatsealing performed slightly better in the reduction of soft or bruised strawberries as well. The research also compared bubble pads and absorbing pads but found no significant differences between the two, probably because the punnets were submitted to very little mechanical stress during the experiment.

“This research confirms the fruitful cooperation with the University of Bologna, which last year provided us with very useful information regarding grapes”, explained Roberto Zanichelli, ILIP’s Marketing Manager. “This means additional contribution given by ILIP to raise better awareness of the interaction between packaging and packaged product, with the additional purpose of reducing food waste, an issue that results in high environmental impact and in which packaging plays a fundamental role.”

In line with this commitment, ILIP is supporting Save Food, an initiative sponsored by FAO with Interpack and Messe Düsseldorf to reduce food waste.

The detailed document containing the research on the evaluation of the effect of different types of packaging on the shelf life and the quality of whole strawberries is available in pdf upon request to marketing@ilip.it.