Yield optimization, microbial load analysis, and sensory evaluation of mungbean (Vigna radiata L.), lentil (Lens culinaris subsp. culinaris), and Indian mustard (Brassica juncea L.) microgreens grown under greenhouse conditions

PLoS One. 2022 May 24;17(5):e0268085. doi: 10.1371/journal.pone.0268085. eCollection 2022.

Abstract

Microgreens have been used for raw consumption and are generally viewed as healthy food. This study aimed to optimize the yield parameters, shelf life, sensory evaluation and characterization of total aerobic bacteria (TAB), yeast and mold (Y&M), Escherichia coli, Salmonella spp., and Listeria spp. incidence in mungbean (Vigna radiata (L.) Wilczek), lentil (Lens culinaris Medikus subsp. culinaris), and Indian mustard (Brassica juncea (L.) Czern & Coss.) microgreens. In mungbean and lentil, seeding-density of three seed/cm2, while in Indian mustard, eight seed/cm2 were recorded as optimum. The optimal time to harvest mungbean, Indian mustard, and lentil microgreens were found as 7th, 8th, and 9th day after sowing, respectively. Interestingly, seed size was found highly correlated with the overall yield in both mungbeans (r2 = .73) and lentils (r2 = .78), whereas no such relationship has been recorded for Indian mustard microgreens. The target pathogenic bacteria such as Salmonella spp. and Listeria spp. were not detected; while TAB, Y&M, Shigella spp., and E. coli were recorded well within the limit to cause any human illness in the studied microgreens. Washing with double distilled water for two minutes has shown some reduction in the overall microbial load of these microgreens. The results provided evidence that microgreens if grown and stored properly, are generally safe for human consumption. This is the first study from India on the safety of mungbean, lentils, and Indian mustard microgreens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Escherichia coli
  • Fabaceae*
  • Fungi
  • Humans
  • Lens Plant* / microbiology
  • Listeria*
  • Mustard Plant
  • Salmonella
  • Vigna*

Grants and funding

This research was funded by DRDO-LSRB (Life Science Research Board), New Delhi (LSRB-333), and the Indian Council of Agricultural Research (ICAR), IARI, New Delhi. “The APC was funded by Dr Ramakrishnan M. Nair, World Vegetable Center, South Asia, ICRISAT Campus Patancheru, Hyderabad, India. Ramakrishnan M. Nair acknowledges support from the long-term strategic donors of the World Vegetable Center: Taiwan, United States Agency for International Development (USAID), UK Government’s Foreign, Commonwealth & Development Office (FCDO), Australian Centre for International Agricultural Research (ACIAR), Germany, Thailand, Philippines, Korea, and Japan, and funding support from the ACIAR Project on the International Mungbean Improvement Network (CROP/2019/144). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.