Effects of Concord grape juice flavor intensity and phenolic compound content on glycemia, appetite and cognitive function in adults with excess body weight: a randomized double-blind crossover trial

Background & Aims: Concord grape (Vitis lambrusca) juice (CGJ) contains a unique combination of polyphenolic compounds with diverse effects on human health. It also has an intense sensory profile that...

Safety, Tolerability and Efficacy of Dietary Supplementation with Concord Grape Juice in Gulf War Veterans with Gulf War Illness: A Phase I/IIA, Randomized, Double-Blind, Placebo-Controlled Trial

Approximately 30 percent of U.S. veterans deployed during the Gulf War (1990–1991) have been diagnosed with Gulf War Illness (GWI), a chronic multi-symptom disorder without widely available specific treatments. We investigated whether the consumption of Concord grape juice (CGJ), rich in anti-inflammatory flavonoids, would be tolerated and safe in individuals with GWI and explored improvement in cognitive function and fatigue. Thirty-six veterans with GWI enrolled in a 24-week randomized, double-blind, Phase I/IIA clinical trial to explore safety, tolerability, and feasibility of 16 ounces daily of commercially available CGJ compared to placebo. Participants completed neurocognitive tests and self-reported surveys at baseline, 12 and 24 weeks. Thirty-one participants (86%) completed the study; no dropouts were related to side effects. Thirty participants (83%) documented ≥80% adherence. There were no statistically significant unadjusted differences between CGJ and placebo groups in change in efficacy measures from baseline to endpoint. We employed general linear regression models controlling for baseline differences between groups which indicated statistically significant improvement in the Halstead Category Test–Russell Revised Version (RCAT) at endpoint in the CGJ group compared to placebo (8.4 points, p = 0.04). Other measures of cognitive functioning did not indicate significant improvements in the adjusted analyses (p-values: 0.09–0.32), nor did the fatigue variable (p = 0.67). CGJ was safe and well-tolerated by veterans with GWI. Our data suggest high tolerability and potential benefit from CGJ in veterans with GWI and can be used to inform future studies of efficacy.

Searching for high pressure processing parameters for Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes reduction in Concord grape juice

Purpose High pressure processing (HPP) has been widely used for high-acid (pH<4.6) juices. The purpose of this study was to investigate optimal parameters aimed at achieving 5-log reduction of the pathogens of reference in Concord grape juice (pH 3.39). Design/methodology/approach Grape juice was inoculated with five strain cocktails of Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes. In total, 11 trials were carried out based on a Central Composite Rotational Design (CCRD). The pressure (P), ranging from 319 to 531 MPa, and dwell time (t), from 35 to 205 s, were tested. The performance of the combinations (P × t) was evaluated by pathogen challenge microbiological assays. Findings E. coli O157:H7 was more resistant to HPP than S. enterica. L. monocytogenes did not grow in unprocessed juice (before HPP). Findings demonstrated that moderate pressures (~400 MPa) and short dwell times (~2 min) were effective in achieving a greater than 5-log reduction in the pathogens of reference. Practical implications Because the maintenance costs of equipment exponentially increase with pressure beyond 600 MPa, significant reductions in process pressure are highly desirable. Originality/value The results of this study can supplement the dearth of information on the applicability of high pressure as a Concord grape juice processing technology in terms of the pathogens inactivation. Furthermore, the use of a cocktail of five strains of pathogens inoculated in Concord grape juice to challenge different HPP parameters has not been reported.