Sprouts are germinated or partially germinated seeds. A sprout consists of the seed, root, stem.[citation needed] The FDA seeks to regulate all businesses that produce sprouts due to numerous outbreaks of food poisoning ("sproutbreaks"). Salmonella and Escherichia coli O157:H7 have been the major causes of sprout-associated illness outbreaks.[citation needed] Commercial sprout processors are asked to follow rigorous FDA Guidelines for production that include multiple laboratory tests of each batch for the presence of pathogenic bacteria, to minimize the threat of food borne illness.[citation needed] Despite these precautions, there continues to be regular recalls and alerts relating to sprouts with more and more restaurants removing them from menus to reduce their liability.[citation needed] In 2011, 52 people died and thousands became ill due to consumption of locally grown organic sprouts in Europe. The two largest U.S. retailers Walmart and Kroger are no longer selling sprouts. "Sprouts present a unique challenge because pathogens may reside inside the seeds where they cannot be reached by the currently available processing interventions," Payton Pruett, Kroger's Vice President of Food Safety, said in an October 19, 2012 news release.[11]
Sprout seeds are soaked in water for usually eight hours and then drained. A high density of seed is placed inside of sprouting equipment or enclosed containers. The seed germinates rapidly due to the high moisture and humidity levels maintained in the enclosures. Seeds can also be sprouted in cloth bags that are repeatedly soaked in water. The sprouting process occurs in dark or very low light conditions. These dark, wet, crowded conditions are ideal for the rapid proliferation of dangerous pathogenic bacteria.[citation needed] After a few days of soaking and repeated rinsing in water (several times a day to minimize spoilage), the processing is complete and the sprouts are ready to consume.
Microgreens are grown in soil or soil-like materials such as peat moss. Microgreens require high light levels, preferably natural sunlight with low humidity and good air circulation. Microgreens are planted with very low seed density compared to sprout processing. Crop times are generally one to two weeks for most varieties, though some can take four to six weeks. Microgreens are ready to harvest when the leaves are fully expanded. Harvesting is usually with scissors cutting just above the soil surface, excluding any roots. Some growers sell them while still growing, rooted in the growing trays so that they can be cut later. Once removed from their growing environment, these trays of microgreens must be used quickly or they will rapidly begin to elongate and lose color and flavor.
The conditions that are ideal for properly grown microgreens do not encourage the growth of dangerous pathogens. These growing methods would not work for the production of sprouts.
With stronger flavors compared to sprouts, they are an excellent ingredient with a wide selection of leaf shapes, textures and colors.
The potential for food safety issues with microgreens may be increasing due to the number of indoor microgreen growing operations in which excessive seed density, low light intensity, low air circulation or most commonly, a lack of GAP (good agricultural practices) and GMP (good manufacturing practices) based food safety procedures. Certain provisions of the Guidance for Industry: Reducing Microbial Food Safety Hazards For Sprouted Seeds [12] may be beneficial and prudent for growers of microgreens to follow