Submitted to: Journal of Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/23/2017
Publication Date: 2/24/2017
Citation: Beaulieu, J.C., Obando-Ulloa, J.M. 2017. Not-from-concentrate pilot plant ‘Wonderful’ cultivar pomegranate juice changes: Volatiles. Journal of Food Chemistry. doi:10.1016/J.foodChem.2017.02.114. Interpretive Summary: To the best of our knowledge, no pasteurized and stored not-from-concentrate ‘Wonderful’ pomegranate juice volatiles have been reported in the literature. Previous characterization of ‘Wonderful’ has developed a consensus suite of volatiles which many researchers assess during flavor and volatile appraisals. A pilot plant with ultrafiltration was used to mimick the dominant U.S. commercial-like pomegranate juice extraction via hydraulically pressing whole fruit. No maceration, blending or concentrating was used and a truly juice was pasteurized and stored at 4 and 25 °C. Forty six compounds were recovered and 38 compounds were routinely isolated and subjected to an ANOVA analysis. Eighteen of the 21 consensus pomegrante compounds were recovered. A few key flavor compounds (ß-pinene, bergamotene and ß-bisabolene) were only recovered in controls (GNP). Ultrafiltration often resulted in significant decreases for many compounds. Conversely, pasteurization resulted in compound increases. Twelve of the consensus compounds (hexanal, (E)-3-hexenol, 1-hexanol, 6-methyl-5-hepten-2-one, a-terpinene, p-cymene, limonene, '-terpinene, nonanal, 4-terpineol and a-terpineol) were routinely isolated throughout storage, and most displayed highly significant decreases during storage. PCA clustering demonstrated clearly which compounds were tightly associated, and how all storage samples behaved very similarly, independent of temperature. We presume that this SPME method with NFC juices delivered a robust ‘Wonderful’ volatile profile that is likely superior qualitatively and perhaps quantitatively to typical commercial offerings.
Technical Abstract: Pilot plant ultrafiltration was used to mimic the dominant U.S. commercial pomegranate juice extraction method (hydraulic pressing whole fruit), to deliver a not-from-concentrate (NFC) juice that was high-temperature short-time pasteurized and stored at 4 and 25 °C. Recovered were 46 compounds, of which 38 were routinely isolated and subjected to analysis of variance to assess these NFC juices. Herein, 18 of the 21 consensus pomegranate compounds were recovered. Ultrafiltration resulted in significant decreases for many compounds. Conversely, pasteurization resulted in compound increases. Highly significant decreases in 12 consensus compounds were observed during storage. Principal component analysis demonstrated clearly which compounds were tightly associated, and how storage samples behaved very similarly, independent of temperature. Based on these data and previous work we reported, this solid phase micro extraction (SPME) method delivered a robust ‘Wonderful’ volatile profile in NFC juices that is likely superior qualitatively and perhaps quantitatively to typical commercial offerings.