Quality Evaluation of Indoor-Grown Microgreens Cultivated on Three Different Substrates

Abstract

The microgreens are innovative products in the horticultural sector. They are appreciated by consumers thanks to their novelty and health-related benefits, having a high antioxidant concentration. This produce can be adopted for indoor production using hydroponic systems. The aim of the present work was to investigate the influence of three growing media (vermiculite, coconut fiber, and jute fabric) on yield and quality parameters of two basil varieties (Green basil—Ocimum basilicum L., Red basil—Ocimum basilicum var. Purpurecsens) and rocket (Eruca sativa Mill.) as microgreens. Microgreens were grown in floating, in a Micro Experimental Growing (MEG®) system equipped with LED lamps, with modulation of both energy and spectra of the light supplied to plants. Results showed high yield, comprised from 2 to 3 kg m−2. Nutritional quality varied among species and higher antioxidant compounds were found in red basil on vermiculite and jute. Coconut fiber allowed the differentiation of crop performance in terms of sucrose and above all nitrate. In particular, our results point out that the choice of the substrate significantly affected the yield, the dry matter percentage and the nitrate concentration of microgreens, while the other qualitative parameters were most influenced by the species.

The Inclusion of Green Light in a Red and Blue Light Background Impact the Growth and Functional Quality of Vegetable and Flower Microgreen Species

“…These specialty crops are also ideally suited for urban agriculture production systems to achieve a sustainable food supply [5][6][7][8] and are now widely promoted for such applications, since they have a short production cycle, high yields per unit area, and small growing space requirements, while also possessing high nutritional values [3,9].…”

Trial Protocol for Evaluating Platforms for Growing Microgreens in Hydroponic Conditions

“…The germination of microgreens seeds will be carried out in darkness at 20-24 • C (depending on the species) and 100% relative humidity [3]. For basil seeds, germination occurred in a climatic chamber in the dark at 24 • C for 3 days [25,61]. After approximately 3 days, the plants are exposed to light and watered daily until the first set of true leaves begin to emerge.…”

“…Among common substrates used for the microgreens production, peat-based media are the most utilized, followed by coconut coir and several synthetic media [25]. Recently, natural fiber-based media-such as jute, cotton, cellulose, etc.-have gained increasing popularity since they could represent a sustainable alternative [43,62].…”

“…The seeds are placed directly in the sterile sublayer. Bulgari et al ( 2021) [25] investigate the influence of three growing media (vermiculite, coconut fiber, and jute fabric) on yield and quality parameters of two basil varieties (green basil-Ocimum basilicum L., red basil-Ocimum basilicum var. Purpurecsens) and rocket (Eruca sativa Mill.)…”

“…However, the advantages of hydroponic platforms and the development of evaluation protocols can lead to a positive influence on the quality of microgreens with higher concentrations of active substances [18,19] and nutrients valuable for human health [20][21][22]. This is why it is necessary to standardize certain cultivation protocols to ensure their quality [23][24][25]. For instance, there is a wide range of environmental impact factors and variation in their relationships to downstream microgreens outputs, which means that there is no single prescription that will guarantee perfect results [26].…”