Submitted to: Food Research International
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/27/2016
Publication Date: 11/30/2016
Citation: Mukhopadhyay, S., Sokorai, K.J., Ukuku, D.O., Fan, X., Juneja, V.K. 2016. Effect of high hydrostatic pressure processing on the background microbial loads and quality of cantaloupe puree. Food Research International. doi: 10.1016/j.foodres.2016.11.029.

Interpretive Summary: Cantaloupe is one of the most important produce. Production, consumption and trade of cantaloupe increased due to its nutritive value, desirable taste, texture and versatility. Cantaloupe has a brief harvest period and large amounts of cantaloupes rot away every year in the farmlands due to the lack of processing techniques. To date, no method is available for preservation of this fruit. Due to market demand, we have investigated for suitable preservation method and developed a nonthermal method to process cantaloupe puree under high pressure to inactivate all natural Microflora responsible for spoilage. This method also showed to preserve the quality attributes of the fruit such as acidity, sugar and other soluble solid content, color, flavor, etc. during refrigerated storage. The results presented in this study indicated high pressure processing as an alternative to traditional thermal processing for preservation of cantaloupe as puree.

Technical Abstract: The objective of this study was to investigate and evaluate the effects of high hydrostatic pressure (HHP) applied to cantaloupe puree (CP) on microbial loads and product quality during storage for 10 days at 4 degrees C. Freshly prepared, double sealed and double bagged CP (ca. 5 g) was pressure treated at 300, 400 and 500 MPa at 8 degrees C and 15 degrees C for 5 min. Microflora populations, brix, pH, color, antioxidant activity, appearance and aroma were measured at 1, 6, and 10 d of storage. Results showed that high pressure treatment of 300 MPa (8 degrees C and 15 degrees C) resulted in reduction of total aerobic plate count from 3.3 to 1.8 log CFU/g. The treatment reduced the populations of native aerobic plate count to non-detectable levels (detection limit 1 log CFU/g) at 400 MPa and 500 MPa pressures at 15 degrees C. Pressure treatment completely inactivated mold and yeast in puree below the limits of detection at day 1 and no regrowth was observed during 10 days of storage at 4 degrees C while mold and yeast on the control cantaloupe grew during storage. High pressure treatment did not show any adverse impact on physical properties as soluble solid content (SSC, 11.2 degrees brix) and acidity (pH, 6.9). The instrumental color parameters (L*, a*, b*) were affected due to HHP treatment creating a slightly lighter product, compared to control, as indicated by higher L* and lower a* values. However the change was not detected by the sensory panel while evaluating appearance scores. Pressure treatment did not affect the antioxidant capacity of puree product compared to control. Visual appearance and sniffing aroma test by panel reveals no adverse changes in the sensory parameters as a result of HHP treatment. HHP method described in this study appears to be a promising way to inactivate spoilage microorganisms in the cantaloupe puree and maintain quality. This study provides a viable option for preservation and market this product.