Physical characterization of frozen fruits from eight cultivars of the North American pawpaw (Asimina triloba)

Abstract

Pawpaw (Asimina triloba [L.] Dunal) is an underutilized fruit native to North America. The fruit has a short shelf life, and browns and softens rapidly after harvesting. These characteristics present a challenge to the advancement of pawpaw as an economically viable specialty crop. This study evaluated the physical characteristics of frozen fruits from eight cultivars of the pawpaw fruit to establish the processing potential of pawpaw fruits. The results show that freeze-thaw cycle may have influenced the peel thickness, peel color, and pulp color of the fruits. Fruits of the Susquehanna cultivar had the highest fruit weight and pulp weight, making them potentially the most suitable for pulp processing. The pawpaw fruits had almost neutral pH ranging between 6.07 ± 0.21 and 6.47 ± 0.11, which could contribute to the rapid browning on exposure to air since an acidic pH is important for slowing enzymatic browning. To aid pawpaw juice extraction, enzymatic treatments may be necessary to increase the juice yield from the pulp. Overleese fruits may be the best for pawpaw juice production. These findings can aid in the selection of processing equipment and guide processors in their efforts to utilize pawpaw fruits to avoid postharvest and post-processing losses.

Correlations between color, textural properties and ripening of the North American pawpaw (Asimina triloba) fruit

“…Since negative a * values indicate green color and positive a * values indicate red color, it is clear that the unripe fruits have a greener skin color compared to the ripe fruits. The skin color of the ripe fruits studied was lighter, and greener than those obtained by Adainoo and others 13 in a study in which ripe fruits had been frozen for weeks before analyses.…”

“…Nonetheless, the color data obtained in this experiment were consistent with the data obtained for four cultivars of pawpaw analyzed by Mcgrath and Karahadian 8 and the data obtained for eight cultivars of pawpaw analyzed by Adainoo and others. 13…”

“…However, since the fruits have a thin peel thickness, there is a high potential for breaking the skin through checking the hardness by touch. 13 Currently, no research has been published testing the correlations between the skin color, which can be determined noninvasively, the textural properties, which are currently the main indices for assessing pawpaw ripeness, and the total soluble solids content (Brix). Establishing good correlations between these two physical properties and the total soluble solids contents will enable farmers to use commercially available portable devices (like handheld color meters and near-infrared total soluble solids sensors) to noninvasively determine the ripeness of pawpaw fruits.…”

A comparative study of edible coatings and freshness paper on the quality of fresh North American pawpaw (Asimina triloba) fruits using TOPSIS-Shannon entropy analyses

“…The pH difference between day 0 and day 15 for both control and 1% chitosan coated fruits was similar. Further, it took up to day 20 for the pH of the 2% chitosan coated fruits to reach a pH less than 5.98, which is the minimum pH for good quality Susquehanna pawpaw pulp according to Adainoo et al (2022) , whereas the 1% chitosan coated fruits recorded an average pH less than 5.98 by day 10. This suggests that the 2% chitosan coating was more effective in controlling the change in pH of the Susquehanna fruits during storage.…”

“…The fruit belongs in the Annonaceae family with many commercially produced tropical fruits like soursop, cherimoya, sugar apple, and others. Pawpaw is a low acid fruit that has a very short shelf life characterized by rapid discoloration of the skin and pulp, and loss in fruit firmness within 5 days ( Adainoo et al, 2022 ; Galli et al, 2008 ). Some studies have attempted to extend the shelf life of the fruit with the application of cold storage technologies.…”