Tuesday, July 31, 2012
Grand Ballroom
The North American pawpaw (Asimina triloba) is the largest tree fruit native to the United States and is in the early stages of commercial production. The pawpaw fruit has a creamy yellow-orange flesh and a flavor resembling a blend of mango, banana, and pineapple. The fruit has a short shelf-life and difficulty with postharvest handling and storage presents an impediment to further commercial development. Production of frozen pawpaw fruit pulp as a value-added product would be one solution to this problem of fruit perishability. However, pawpaw fruit pulp extraction is labor intensive and rows of large inedible seeds contained in the fruit impede processing, and valuable pulp may be lost through ineffective extraction methods. The objective of this study was to determine 1) the processed pulp recovery rate of three pawpaw cultivars, and 2) if year to year climatic conditions influence pulp recovery rate. Three sets of five ripe fruit each of three commonly available pawpaw cultivars (Mitchell, Sunflower, and Susquehanna) were selected. These cultivars were selected based on varietal fruit size, with Mitchell being a small fruited cultivar, and texture differences that were previously observed; Susquehanna tends to have a firm flesh. The fruit were cut in half and pulp and seed were scooped out with a spoon and placed in a modified Roma Sauce Maker and Food Strainer with a shortened grape spiral and a squash/pumpkin screen. This device separates seeds from pulp and macerates the pulp. The pulp/seed mixture was run through the strainer 3 times to obtain as much processed pulp as possible. In 2010, when the total rainfall was 4 inches below normal, processed pulp recovery rate varied significantly among cultivars, with Susquehanna (44%) and Sunflower (41%) having a greater percentage of pulp recovered from fruit compared to Mitchell (24%). In 2011, when the total rainfall was 22 inches above normal, processed pulp recovery rate also varied significantly among cultivars, with Susquehanna (49%) and Sunflower (44%) having a greater percentage of pulp recovered from fruit compared to Mitchell (28%). Mitchell fruit also had over twice the percent seed compared to the other cultivars. There was a trend for fruit grown under high rainfall conditions in 2011 to have a higher pulp recovery rate. With large fruit weights and a high rate of processed pulp recovery, which enables more efficient processing, the cultivars Susquehanna and Sunflower are good choices for pawpaw growers and processors.