|CHEN, HAIQIANG - University Of Delaware|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 2/5/2014
Publication Date: 6/21/2014
Citation: Lacombe, A.C., Niemira, B.A., Gurtler, J., Boyd, G., Sites, J.E., Fan, X., Chen, H. 2014. Effects of nonthermal atmospheric cold plasma on blueberry native microbiota and sensory attributes. Meeting Abstract. , IFT Annual meeting., New Orleans, LA., June 21-24,2014., Volume 1, Page 1.
Technical Abstract: Nonthermal processing interventions are important steps in decontaminating and/or preserving fresh fruits, such as blueberries. Cold plasma (CP) is a novel nonthermal technology potentially useful in food processing settings. The objectives of this work were to determine CP reduction of blueberry background microbiota (potential spoilage microorganisms), and impact of CP on color, firmness, and anthocyanins. Blueberries (10g) were weighed into sterile 4 oz. glass jars. Samples were treated with atmospheric CP for 0, 15, 30, 45, 60, 90, or 120 seconds at a working distance of 7.5 cm (from what?) with a mixture of 4 cubic feet/minute (cfm) of CP jet and 7 cfm of room temperature air. Temperature readings were taken with an infrared camera prior to and following CP treatments. Blueberries were sampled for total aerobic plate count (APC) and yeast/molds immediately after treatment and after storage for 1, 2, and 7 days at 4 degrees C. In addition, blueberries were analyzed for compression firmness, surface color, and total anthocyanins, immediately after each treatment. CP resulted in significant (P < 0.05) reductions of APC on treated berries. Immediately after treatment, a 90 seconds exposure resulted in a 1.6 log CFU/g reduction. After 1 day, APC on berries treated for 30s was approximately 1 log CFU/g lower than the control. After 7 days, the shortest CP treatment (15s) resulted in a microbial suppression of 2 log CFU/g. Treatments longer than 60 seconds resulted in significant reductions in firmness and the 120 seconds treatment reduced total anthocyanins and color (L, a, and b). These results indicate that treatments with CP can inactivate potential spoilage microorganisms on blueberries without adversely impacting sensory attributes. Processors of berries will be able to use optimized CP treatments to improve the freshness, safety, and quality of these commodities.