Redomesticating Almond to Meet Emerging Food Safety Needs

Abstract

Almond is a desirable and high-quality food source where the presence of nut allergens and a vulnerability to aflatoxin and Salmonella contamination represent threats to consumer safety. In 2019, over 1 billion kg. of almonds, representing over 80% of the world total, were produced in California from a relatively few varieties with a very narrow genetic base. To address emerging needs mandated by cultural and climate changes, new germplasm has been introduced combining peach as well as wild peach and wild almond species. Advanced breeding selections incorporating exotic germplasm into a genetic background compatible with commercial production in California have demonstrated sizable reductions in level of kernel immunoreactivity as well as opportunities for improved control of aflatoxin and Salmonella. Breeding strategies employed include direct selection for reduced kernel immunoreactivity from an introgression enriched germplasm, the integration and pyramiding of resistance to multiple components of the aflatoxin disease-insect complex, and introduction of novel nut and tree traits to facilitate mechanized catch-frame field harvesting to avoid contamination with soil-borne pathogens such as Salmonella and Escherichia coli, as well as agrochemical residues.

Linking diverse salinity responses of 14 almond rootstocks with physiological, biochemical, and genetic determinants

“…In almonds, rootstock plays a key role in the success of a variety. Different types of rootstocks used in almonds include peach-based rootstocks, peach hybrids, almond-based rootstocks, plum-based rootstocks, peach/almond hybrids, plum/peach hybrids, and complex hybrids 14 , 15 . As the salinity tolerance of a plant depends on the ability of its roots to exclude or retain ions, in an almond variety, the salinity tolerance will largely depend on the nature of its rootstock.…”

Postharvest processing of tree nuts: Current status and future prospects—A comprehensive review

“…(2) The almonds directly contact the soil for long periods of time during natural drying, which introduces a pathway for severe insect damage and contamination by pathogenic microbials (Gradziel et al, 2000(Gradziel et al, , 2020Wang et al, 2013;Yu et al, 2018); (3) There is no technology available for monitoring and detecting insects during stockpiling and storage, which results in a significant product loss due to insect damage or a large amount of chemicals use from frequent fumigation. In Europe, almonds mainly grow in Spain, and are harvested off-ground and de-hulled in-field.…”

“…Such processes are shown in Figure 4. Currently, there are three major problems with this procedure: (1) The large amount of dust generated during the sweeping and picking up spreads away in the air, causing pollution and impacts human health (Baticados et al., 2019); (2) The almonds directly contact the soil for long periods of time during natural drying, which introduces a pathway for severe insect damage and contamination by pathogenic microbials (Gradziel et al., 2000, 2020; Wang et al., 2013; Yu et al., 2018); (3) There is no technology available for monitoring and detecting insects during stockpiling and storage, which results in a significant product loss due to insect damage or a large amount of chemicals use from frequent fumigation. In Europe, almonds mainly grow in Spain, and are harvested off‐ground and de‐hulled in‐field.…”