Location: Food Quality LaboratoryTitle: Postharvest biology, quality and shelf-life of buckwheat microgreens Author
Submitted to: LWT - Food Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/19/2012
Publication Date: 4/1/2013
Publication URL: http://handle.nal.usda.gov/10113/59356
Citation: Kou, L., Luo, Y., Yang, T., Xiao, Z., Turner, E.R., Lester, G.E., Wang, Q. 2013. Postharvest biology, quality and shelf-life of buckwheat microgreens. LWT - Food Science and Technology. 51(1):73-78. Interpretive Summary: Microgreens (seedlings of green vegetables and herbs) are gaining in popularity as a new culinary ingredient, providing intense flavors, vivid colors, and phytonutrients. However, their short shelf life often results in considerable postharvest losses and necessitates high cost air cargo shipping. The present study investigated the effects of postharvest handling conditions on the quality and shelf life of buckwheat microgreens. Results indicated that modified atmosphere packaging and cold storage are major factors affecting buckwheat microgreen quality. Under the optimized packaging and storage conditions, buckwheat microgreens can be stored for up to 21 days and still retain acceptable quality. This research provides scientific information to the fresh produce industry on how to extend storage life of microgreens by optimizing postharvest handling practices. Significant extension of shelf life makes it possible to ship the microgreens via ground transportation with significant cost savings, which can in part be passed on to the consumer as lower prices in the market.
Technical Abstract: Buckwheat microgreens are rich in antioxidants and provitamins/vitamins, including flavonoids, carotenoids, and a-tocopherol. However, short shelf life has limited their commercial use. The purpose of this study was to optimize storage conditions to extend the shelf life of buckwheat microgreens. Storage temperature, package film oxygen transmission rate (OTR), and wash conditions were assessed for their effects on quality and shelf life. Temperature significantly (P < 0.0001) affected the package atmosphere and product quality. At the end of storage, samples stored at 5 and 10 °C exhibited lower microbial growth and tissue electrolyte leakage, and higher overall quality scores, than those stored at 15 and 20 °C. Package film OTR significantly (P < 0.05) affected package headspace atmospheric composition, and thus the quality and shelf life of microgreens. Buckwheat microgreens enclosed in optimum OTR package films retained freshness and overall product quality. A chlorine (100 mg/L) wash significantly (P<0.05) reduced the initial microbial populations; however, after 7 days, microbial counts in the washed samples rebounded. These findings indicate that buckwheat microgreens should be stored at 5–10 °C with moderately high O2 and moderately low CO2 levels to maintain optimal quality and achieve maximal shelf life.