Mitigating Food Loss and Waste
ARS research reduces food loss and waste and transforms food waste into new marketable products for consumers. The USDA Economic Research Service determined that annually 31 percent of the 430 billion pounds of U.S. food supplies at retail and consumer levels goes uneaten and is otherwise wasted. In 2015, USDA joined with the U.S. Environmental Protection Agency to set a goal for the Nation to cut its food loss and waste by 50 percent by the year 2030. The following FY 2019 accomplishments illustrate ARS efforts to achieve this goal. Hyperlinked accomplishment titles point to active parent research projects.
New freezing technology retains fresh-like fruit quality when thawed. Freezing is a well-established technology used to prolong seasonal fruit and vegetable shelf-life. However, current freezing technologies (both slow and fast) ruptures cells, resulting in juice loss when thawed, which leads to suboptimal flavor, juice content, and texture qualities. Together with colleagues at the University of California–Berkeley, ARS scientists in Albany, California, investigated a technology first developed to preserve human organs for transplanting called isochoric (constant-volume) freezing to extend the shelf life of food products and maintain their physical and nutritional properties. The researchers evaluated isochoric freezing to preserve the quality of sweet cherries and found the technology resulted in thawed fruit that were indistinguishable from fresh cherries in terms of juice loss, texture, structure, ascorbic acid content, and antioxidant activity. The isochoric method also uses 70 percent less energy compared with conventional freezing methods. These findings promise to disrupt the $54 billion U.S. frozen foods market by enabling frozen products that are thawed to have extended shelf-life and fresh-like taste, texture, juiciness, and nutrition.
Tough yet flavorful ‘Keepsake’ strawberry cultivar. Strawberries are a valuable crop in the United States, so loss of a small percentage of the crop to disease or physical degradation in the field or during postharvest storage is costly to growers and consumers. ARS researchers in Beltsville, Maryland, released and patented ‘Keepsake’, a mid-season, “spring-bearing” strawberry with fewer rotted or physiologically degraded fruits in the field or after refrigerated storage. The fruits are very sweet with outstanding flavor and are firm and tough enough for commercial handling. ‘Keepsake’ is expected to be of greatest value to growers in the Mid-Atlantic and northeastern States, especially to those who must store harvested fruit for delivery to market. Plants of ‘Keepsake’ were directed to nine U.S. and Canadian nurseries for propagation and licensing for sale. Nursery and grower demand for ‘Keepsake’ already exceeds supply.
New, automated in-field apple sorting machine. Automated in-field sorting enables low-quality or inferior fruit to be separated from fresh-market, higher-quality fruit at harvest, which allows for better efficiency and control during postharvest apple storage and packing and reduces overall food loss. ARS scientists at East Lansing, Michigan, designed and constructed a new, automated in-field apple sorting system. This simple system is compact, reliable, and capable of sorting 11 or more apples per second. Laboratory tests achieved 100 percent sorting accuracy with superior grading repeatability along with no bruising damage to fruit. This infield sorting system is being tested at Schwallier's Country Basket, a commercial orchard, and has been incorporated into the ARS-developed and commercialized self-propelled apple harvester. U.S. apple growers adopting this new in-field sorting technology can achieve significant cost savings in postharvest handling of harvested fruit, improve postharvest management, and reduce postharvest fruit loss.
New fruit storage clamshell container with superior freshness retention. A new clamshell container for fresh-fruit storage that maintains optimum humidity, prevents fruit weight loss in storage, and does not induce a modified atmosphere, was designed by ARS scientists in Fort Pierce, Florida. The new clamshell has openings in the shell with an opening-to-surface ratio of 0.44 percent in comparison with present-day commercial clamshells with an opening-to-surface ratio of 2.83 percent. The smaller opening ratio, developed over a period of 11 years in 37 experiments, is large enough so that air in the clamshell maintains firmness of sweet cherry stems, and freshness of litchis, strawberries, blueberries, Chinese bayberries, apricots, loquats, and cherry tomatoes. Quality attributes of the packaged fruits were generally maintained more effectively in these ARS-designed clamshells, especially for attributes susceptible to water loss such as shriveling, desiccation-induced browning, and/or drying of pedicels in cherries, calyx of strawberries, pericarp of litchis, peel shriveling of cherry tomatoes, and softening of blueberries and strawberries.
New commercial control strategies to combat apple superficial scald. Superficial scald is a browning disorder of apple peels that occurs following postharvest chilling and contributes to fruit quality losses in markets where scald control compounds are restricted. ARS scientists in Wenatchee, Washington, identified gene activity following chilling injury. They found chilling injury is a gene-based cumulative factor that is preventable if apples are exposed to low oxygen, high carbon dioxide (relative to air) storage conditions within 7 days after harvest. Also, they demonstrated that postharvest chilling hot water treatment can effectively control scald. These findings indicate it is possible to use nonchemical control strategies to reduce or eliminate scald from both conventional and organic cold chains within existing commercial storage facilities. These control measures will reduce commodity and economic losses for apple producers, distributers, and retailers for markets where no consistent superficial scald mitigation strategy previously existed.
A fresh fruit and vegetable cleaning system that prevents bacterial survival. In current commercial fresh fruit and vegetable processing plants, the accumulation of organic materials in washing tanks allows for unhealthy bacterial survival as chlorine in the water is depleted. ARS scientists in Beltsville, Maryland, invented a novel “in-flight” non-soaking cleaning system that removes organic material early in the process without damaging the fresh produce. This new process cleans all produce surface areas and effectively removes organic matter from cut surfaces while improving processing control and efficacy, thereby allowing produce to be stored longer without bacterial decay and reducing food waste. This system uses a combination of sanitizers and a consistent concentration of chlorine that removes bacterial contamination while eliminating toxic chlorine byproduct formation found in dechlorinating washing-tank systems. This in-flight system, which has a relatively small footprint, also allows for exceptionally efficient use of space in processing plants. Working with Church Brothers Fruit Company, ARS is scaling up this technology for commercialization.