Improving Shelf Life of Fresh Pack Maine Wild Blueberries

View the project final report

Commodities

• Fruits: berries (blueberries)

Practices

• Crop Production: postharvest treatment, season extension
• Education and Training: demonstration, farmer to farmer, on-farm/ranch research, participatory research, technical assistance, workshop
• Farm Business Management: value added

Family wild blueberry farms in Maine (20-200 acres) do not have the capital to invest in the development of complete cold chains that extends the shelf life of their berries from the field to consumers. There are also physical differences between highbush and wild blueberries that affect post-harvest handling such as small berry size, thin skins, and a range of ripeness in every pint. Therefore, Maine producers have developed their own innovative methods of maintaining berry quality, which has resulted in a wide range of fresh wild blueberry quality. Listening to growers, wild blueberry storage temperatures range from 40°F to 70°F and very few consider relative humidity or airflow as storage factors. The objectives of this project are to 1) identify the ideal storage temperature for fresh wild blueberries on small farms where only one cooling step is feasible, 2) survey the current temperature and relative humidity of fresh pack wild blueberry buildings in Maine, and 3) disseminate storage temperature findings and incorporate post-harvest handling education into the University of Maine Wild Blueberry Extension Program. Overall, this is a collaborative research and outreach project designed to reach both organic and conventional wild blueberry producers with the goal of improving the shelf life and quality of fresh packaged Maine wild blueberries. This will allow wild blueberry growers to reach worthwhile markets, thereby improving farmer livelihoods and supporting our regional food system.

The objectives of this project are to:

1. Identify the ideal storage temperature for fresh wild blueberries on small farms where only one cooling step is feasible.
2. Survey the current temperature and relative humidity of fresh pack wild blueberry buildings in Maine.
3. Disseminate storage temperature findings and incorporate post-harvest handling education into the University of Maine Wild Blueberry Extension Program.

Questions we will answer include:

A. In the absence of a full cold chain (ability to keep berries cold from field harvest to market), what is the ideal temperature to which wild blueberries should be cooled to extend their shelf life as long as possible for the fresh pack market?

B. How does wild blueberry fruit quality change over the course of 30 days in wild blueberries that are stored at 34, 40 and 50 degrees for one week?