Performing Department
(N/A)
Non Technical Summary
High Voltage Atmospheric Cold Plasma (HVACP) treatment of agricultural products is an emerging non-thermal processing (NTP) technology that effectively reduces aflatoxins (AF) and microorganisms on almonds, other tree nuts and peanuts. HVACP-based NTP provides enhanced food safety by reducing incidences of food-borne illness. It is a cost-effective and environmentally friendly processing technology that addresses several NIFA National Challenge Areas. These include: 1) Global food security and hunger alleviation by increased protection of agricultural products from disease and pests and reduced food losses; 2) Low to no impact on climate change by providing an environmentally friendly, low energy and low carbon footprint alternative to chemical and thermal processes; and 3) Food safety by reducing the incidence of food-borne illnesses and death through an improved food processing technology. Industry adoption of this novel NTP technology will provide higher quality almonds, other tree nuts and peanuts to the consumers and increase global demand for U.S. almonds and other tree nuts.Atmospheric cold plasma is a natural phenomenon that has been harnessed and adapted for industrial purposes. The first atmospheric, low temperature plasma was invented by Werner von Siemens in 1857 (Siemens, 1857). Air was passed between two parallel plates containing an electrical spark (corona discharge) to generate ozone. Plasma can be generated in any gas environments (e.g. air, O2, He, N2, Ar, Ne, CO2) with either DC or AC current (Roth, 1995). HVACP capitalizes on the chemical properties of gases and the physics of electric field. When a gas is subjected to a voltage gradient of adequate strength; electrons can be stripped from the gas molecules (ionization). These electrons react with the bulk gas generating light, UV, and unique reactive gas species (ozone, oxides of nitrogen, peroxides, atomic oxygen, etc.), many of which can alter mycotoxins on the surface of almonds, other tree nuts, peanuts as well as on maize, wheat etc. and render mycotoxins non-toxic. In the 2017 USDA-NIFA-SBIR-005943 Phase I grant, NanoGuard demonstrated that a non-thermal processing using HVACP can significantly reduce aflatoxins on almonds without impacting quality. NanoGuard has also demonstrated that the reactive gas species (RGS) in HVACP have excellent bactericidal properties and they could therefore inactivate bacteria, fungi and mold on tree nuts, peanuts, corn, etc. as an added benefit.Mycotoxins are secondary metabolites produced by specific molds and fungi that are toxic to humans and livestock at low part per billion (ppb) levels (Pankaj et al., 2018; Sarangapani et al., 2018; Shi et al.,2017; Bourke et al., 2017;). These mycotoxins are responsible for a range of health issues that have tremendous economic impact in both the human and animal nutrition industries. The Food and Agriculture Organization (FAO) has estimated that 25% of the world's crops are affected by mycotoxins each year, with annual losses of around one billion metric tons of food and food products. Economic losses occur because of: 1) yield loss due to diseases induced by toxigenic fungi; 2) reduced crop value resulting from mycotoxin contamination; 3) losses in animal productivity from mycotoxin-related health problems; and 4) human health costs. Additional costs associated with mycotoxins include the cost of management at all levels - prevention, sampling, analysis, mitigation, litigation, and research costs. Significant economic losses resulting from mycotoxins are well documented along the food and feed supply chains: crop producers, animal producers, distributors, processors, consumers, and society as a whole (due to health care impacts and productivity losses). Estimates of the costs of mycotoxins in the United States vary: one report estimated $0.5 to $1.5 billion/year (Council for Agricultural Science and Technology, 2003) and another estimated $5 billion/year for the U.S. and Canada (WHO/FAO, 2002).The highest valued tree nut crop in the United States is almonds, generating $6.4 billion in 2014 with a total production of approximately 2 billion pounds (USDA ERS, 2015). The initial subjective forecast for the 2017 California almond production is 2.2 billion pounds (USDA NASS, 2017). Mycotoxin contamination in almonds, primarily aflatoxins, is a constant concern. Aflatoxins are produced by the fungi Aspergillus flavus. Good agricultural practices in tree nuts are recommended for prevention of contamination and growth of Aspergillus flavus, such as keeping product dry during storage. However, aflatoxin production can occur seasonally to varying degrees and is most problematic under wet harvesting conditions or periods of heavy rain when air humidity is high, leading to favorable growth conditions. The tree nut as well as the peanut industries are looking for a simple, cost effective and environmentally friendly solution for reducing mycotoxins on nuts without compromising product integrity. NanoGuard's HVACP-based non-thermal processing technology is a perfect solution to mitigate the post-harvest mycotoxin problem facing the almond industry, in particular, and tree nut as well as peanut industry in general.There is an increasing global demand for food that is fresh, free of pathogens and toxins, and has longer shelf-life. Consumer attention to nutrition, especially awareness and concerns of the potential hazards of preservatives and additives during processing, is also fueling demand for minimally processed food that is safe but retains high nutritional value, texture, and flavor. The recent reports on microbial contaminated food has significantly elevated consumer awareness on food safety. Because non-thermal processing through HVACP reduces mycotoxins and microorganisms of agricultural products, it must be of public interest to bring this technology to commercialization. HVACP-based non-thermal processing assures global food security and reduce hunger by increased protection of agricultural products from disease and pests and reduced food losses. This post-harvest processing technology is cost-effective and environmentally friendly, and it will promote the export of U.S. agricultural products, bringing prosperity to farmers and growers. With the help of this state-of-the-art technology, U.S. tree nut growers and exporters can stay competitive in the global market place by reducing the losses from aflatoxin contamination.
Animal Health Component
90%
Research Effort Categories
Basic
5%
Applied
90%
Developmental
5%
Goals / Objectives
Technical Objectives1. Build and test a 450-kg capacity HVACP system for treating almonds based on Phase I results and know-how.2. Perform 60-minutes treatment of almonds in the newly built 450-kg HVACP system. a. Examine the quality of the above HVACP-treated almonds. b. Examine almond oil quality of HVACP-treated almonds. c. Conduct sensory evaluation of HVACP-treated almonds.3. Examine toxicity of HVACP-treated aflatoxin on almonds.4. Implement intellectual property strategy.5. Develop regulatory approval pathway.6. Implement market and business development plan (commercialization plan for almonds).7. Expand the business opportunities for HVACP technology beyond almonds.
Project Methods
NanoGuard's HVACP technology can deliver significant aflatoxin reduction on almonds and the technology can be scaled to larger treatment volumes without restriction. In Phase II, further development of the technology will occur in constructing a treatment system to treat 450 kg of almonds for sixty minutes. NanoGuard will work with several vendors to design and build a commercial grade HVACP system that can treat 450 kg (1000 × scale-up of the Phase I HVACP system) of almonds per hour for aflatoxin reduction. To build this system, NanoGuard will use its proprietary knowledge and expertise along with its partners to scale-up the electrodes, plasma generator, and contactor developed during the Phase I research. The system will be tested for efficacy and robustness. Operational data from the scaled-up system will be used to develop a techno-economic model (TEM) for the treatment of almonds for aflatoxin reduction. The purpose of the TEM is to determine an operating point or a set of operating points that fall inside an operating envelope of the HVACP process that provides a cost to treat that makes it commercially viable.Approximately 450 kg of almonds will be treated for 60 minutes in this scaled-up commercial grade HVACP system for aflatoxin reduction. The treated almonds and almond oil derived from the treated product will be examined for quality and sensory attributes to be consistent with commercial standards. Analysis of the air above almonds in storage bins (head-space analysis) is commonly used to assess the level of rancidity of almonds during storage. Rancidity causes nuts to have an unpleasant smell or taste. It is due to hydrolysis and/or autoxidation of fats into short-chain aldehydes and ketones which are objectionable in taste and odor. When these processes occur in almonds, undesirable odors and flavors can result. Head-space analysis is an analytical method used to evaluate the rancidity of food oil. The same method will be conducted on HVACP-treated and untreated almonds soon after treatment and during storage to assess the effect (if any) of HVACP treatment on rancidification of almonds. The current plan is to conduct the headspace analysis in an outside lab who does this routinely for the edible oils with guidance from scientists at the Almond Board of California (ABC). Almonds after treatment will be extracted using hexane and the oil will be analyzed for peroxide value (PV), anisidine value (AV), totox value, acid value, thiobarbituric acid (TBA) value, iodine value (IV) and fatty acid composition for oil quality. Peroxide, anisidine, totox and thiobarbituric acid values are indicators of fatty acid oxidation.For conducting the sensory testing, NanoGuard will identify a set of key sensory attributes that are relevant to almond industry as part of the testing protocol. NanoGuard will seek guidance from ABC in identifying the sensory attributes. Appropriate experimental design and statistical method will be used to generate and interpret the sensory data, and to assess the effect of HVACP treatment, if any, on the quality and integrity of almonds. Once satisfactory analytical measures are found from HVACP treatment of almonds, a taste testing of the HVACP-treated almonds by a trained sensory panel will be initiated. This sensory testing will be overseen by Dr. Keener and will be used to evaluate the taste, aroma, appearance, flavor and texture characteristics of both HVACP-treated and untreated almonds immediately after treatment and after 28 days of storage.The analytical methods (HPLC and ELISA) that NanoGuard have used for the efficacy of HVACP treatment showed only the level of aflatoxin reduction on almonds due to treatment. These methods measured the quantity of aflatoxin left on almonds after treatment; but did not confirm that the treatment rendered aflatoxin non-toxic or whether the degradants of aflatoxin resulted from HVACP treatment are non-toxic. To confirm that the aflatoxin degradants from HVACP treatment are non-toxic, NanoGuard will develop an invivo toxicology model system using brine shrimp (Artemia). Brine shrimp have been extensively used to evaluate the toxicity in pollution research as a test organism and it is an acceptable alternative to the toxicity testing of mammals in the laboratory. The fact that millions of brine shrimp are so easily reared has been an important help in assessing the effects of a large number of samples on the shrimps under well controlled experimental conditions. Regulatory agencies around the world consider the brine shrimp toxicology results acceptable in environmental safety assessment of new products and/or processes.