Location: Healthy Processed Foods Research
2018 Annual Report
Objectives
The long-term goal of this project is to develop novel methods, and define measure and mitigate attributes that adversely impact the quality of foods. Specifically, during the next five years we will focus on the following objectives:
Objective 1: Enable novel commercial methods for prevention or removal of defects and contaminants in foods.
• Subobjective 1A: Develop techniques for detection and removal of potatoes affected by Zebra Chip disorder from the processing line.
• Subobjective 1B: Develop X-ray based alternatives to radioisotopes for irradiation.
Objective 2: Integrate physical, chemical, sensory, and biological changes from raw and commercially processed food products, including, olives and grapes.
• Subobjective 2A: Pinpoint and identify impact aroma compounds of raw materials and commercially processed products from specialty crops including grapes and olives using gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). Identify precursors (and eventually pathways) of such impact aroma compounds and study flavor variation in different varieties.
• Subobjective 2B: Isolate and characterize phytonutrients in raw materials and food products from grapes, olives, and other specialty crops. Determine the effects of processing on the levels of these constituents and also monitor changes in biological activity (i.e., antioxidant activity).
Objective 3: Integrate measurable allergenic properties with methods to mitigate food allergens in nuts and dairy.
• Subobjective 3A: Identify, characterize, and develop methods for the detection of food allergens in tree nut and other foods.
• Subobjective 3B: Investigate and differentiate allergen cross-reactivity and multi-sensitization and study the effects of processing methodologies on allergenicity.
Approach
1A: Acquire x-ray images and NIR spectra from whole potatoes (reflection) and through slices (transmission). Analyze slices for moisture and sugar, followed by frying and color evaluation. Develop calibration equations for prediction of Zebra Chip (ZC), moisture content, sucrose, and glucose and investigate correlations between ZC and moisture and/or sugar. Isolate appropriate subsets of NIR absorbance values as input features for standard statistical classification techniques. Test appropriate optics that can measure absorption at the determined wavelengths for the ability to evaluate ZC. Observe x-ray images for differences between potato classes and develop detection algorithms. 1B: Design, build, and test x-ray based irradiation units was alternatives to traditional gamma based units using two technologies: traditional x-ray tubes and a higher power prototype x-ray emitter system.
2A: Extract aroma compounds from grapes and olives using GC. Identify precursors and study flavor variation in plant varieties. Have judges evaluate ability to detect odor from each compound’s effluent from a GC column, with compounds detected in the most dilute sample considered to be impact aroma compounds. Identify acquired capillary GC-MS spectra using established libraries to identify food constituents. Quantify food constituents by GC-MS by comparing the areas of characteristic mass fragment ions of the compounds with that of 2-undecanone (m/z 170). Calculate odor activity values by dividing the determined concentrations by their odor thresholds. For confirmation, compare synthetic blends of identified odorants with those of the original raw and processed products using sensory panels.
2B: Extract homogenates from processed and unprocessed food components and analyze using an HPLC-diode array detector. Identify constituents by comparison of retention times and UV/Vis spectra of unknown peaks with those of authentic standards and verify by HPLC-MS, NMR or IR if necessary. Determine weight and total phenolic content for each homogenate. Evaluate antioxidant activity by the DPPH and ABTS procedures. Determine effects of processing by comparison.
3A: Isolate 2S albumins from nuts and express recombinantly to assess their allergenicity using sera from allergic patients. Isolate and express profilin protein for comparative studies. Develop protocols to purify 2S albumin allergens in other nuts including almond, pine nut, coconut, macadamia nut, and optionally chestnut. Determine the peptide sequences by N-terminal peptide sequencing and mass spectrometry. Develop antibody based methods for detecting food allergen and allergic food.
3B: Isolate and clone hazelnut allergens following established protocols. Assay association with serum IgE from patients known to react to peanut and/or hazelnut. Frequency of IgE recognition of allergens will reflect cross-reactivity and multi-sensitization. Process samples by extrusion to investigate processing effects on allergenicity.
Progress Report
In support of Sub-objective 1A, calibration equations for prediction of Zebra Chip (ZC), moisture content, sucrose, and glucose have been developed and correlations between ZC and moisture and/or sugar have been identified. Appropriate subsets of near-infrared (NIR) absorbance values (wavelengths) as input features for standard statistical classification techniques have been isolated. The manuscript describing this work has been published. This Sub-objective is fully on schedule.
Related to Sub-objective 1B, x-ray dose mapping (measuring the delivered dose over a discreet volume) has been performed for several x-ray irradiation units, allowing comparison with dose distributions for gamma irradiators. This helps to evaluate x-ray as a suitable substitute for gamma irradiation.
In relation to Sub-objective 2A, aroma compounds in different rice varieties were identified and quantified using gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Principal component analysis (PCA) and supervised partial least squares-discriminant analysis (PLS-DA) multivariate statistical methods were used to separate the aromatic and non-aromatic genotypes. These experiments will help in selecting aromatic rice genotypes to be grown in the U.S. and distributed worldwide.
In support of Sub-objective 2B, the phenolic composition of non-fermented jaboticaba pomace (solids derived from the skin, seeds and pulp after juice extraction) and fermented pomace (solids remaining after wine production) were compared using High Pressure Liquid Chromatography coupled to Electrospray Ionization-Time of Flight-Mass Spectrometry HPLC/ESI-TOF-MS. Fermented pomace contained higher concentrations of quercetin and myricetin, while non-fermented pomace contained higher levels of ellagic acid, cyanidin 3-O-glucoside, and delphinidin 3-O-glucoside. Fermented pomace added to food products enhances color as well as a number of important biological activities to control microbes, diabetes, obesity and chronic obstructive pulmonary disease (COPD).
Related to Sub-objectives 3A and 3B, the gene for the 7S protein of almond has been isolated and the coding sequence of protein has been cloned and shuffled into the final expression vector and confirmed by DNA sequencing. The protein has been expressed and purified. De-identified sera from almond allergic patients have been obtained and used to test whether the newly purified protein is a food allergen. In addition, a novel food allergen from a new protein family has been identified.
Accomplishments
1. A novel irradiation system for the laboratory. Irradiation is a widely used laboratory tool for many areas of research. However, due to growing difficulties associated with acquiring, maintaining, and transporting radioactive materials, the future availability and practicality of radioactive sources is uncertain. Commercially available x-ray irradiators are large, expensive, and not practical for most laboratories. In collaboration with researchers at the University of Hawaii, Manoa, scientists in Albany, California, constructed an irradiation system from a small, simple, and inexpensive Faxitron x-ray imaging unit capable of delivering relatively high doses on samples placed in a small containment vessel designed to snap into the neck of the x-ray window. This allowed irradiation experiments on Coconut Rhinoceros Beetles (CRB) in the very confined space of the CRB containment facility without disrupting the normal rearing activities. This system makes small scale irradiation simple, economical, and safe.
2. Rice flavor and cooking quality characteristics. The U.S. is a leading global rice producer, with a production value of $2.25 billion in 2017. Researchers in Albany, California, and Universidade Federal de Pelotas, Brazil, discovered 10 volatile compounds as discriminants between aromatic and non-aromatic rice genotypes grown in Brazil. Specifically, 2-Acetyl-1-pyrroline was identified only in aromatic genotypes. Genotypes BR4 and BR5 exhibited the best general performance since their volatile compounds results indicate less off-flavors (hexanal and 1-hexanol), higher 2-acetyl-1-pyrroline content, and similar cooking time and hardness to genotypes IRG and JAS. These results help rice farmers, industry, and researchers in selecting convenient genotypes of aromatic rice to be grown in the U.S. and distributed worldwide. This work also serves as a starting point for future work on rice authenticity.
3. A new technique for Terpenoid biosynthesis. Terpenes constitute the largest class of natural products and are widely used in the flavor and fragrance industry. In addition to their pleasant and desirable odors, they also have diverse biological activities including antibacterial, antifungal, anti-cancer, antioxidant, and antifeedant. Terpenes have complex structures that make their chemical syntheses difficult. Researchers in Albany, California and University California, Davis, used computational chemistry, i.e., density functional theory (DFT) calculations, to elucidate a new terpene biosynthetic pathway. Knowledge of these pathways provides critical insight for producing terpenoids on an industrial scale.
4. Crystal structure of Brazil nut allergen Ber e 2 solved. Food allergies negatively impact the utilization of agricultural products. Tree nuts cause as many fatal and near-fatal food allergy cases in the U.S. as peanuts. However, little knowledge is available about tree nut allergens in general and Brazil nut allergens in particular (compared with information about peanut allergens). Brazil nut allergen, Ber e 2, was the target of investigation when the field of protein research was in its very early stage more than one and a half centuries ago, but its structure remained elusive. ARS researchers at Albany, California, and their collaborators, have solved the Ber e 2-crystal structure for the first time. The information may be used to guide future research in understanding the allergenicity of food allergens and their cross-reactivity.
Review Publications
Liang, P., Haff, R.P., Hua, S.T., Munyaneza, J.E., Yilmaz, M.T., Sarreal, S.L. 2017. Nondestructive detection of zebra chip disease in potatoes using near-infrared spectroscopy. Biosystems Engineering. 166:161-169. https://doi.org/10.1016/j.biosystemseng.2017.11.019.
Liang, P. 2015. Infrared spectroscopy detection of fungal infections and mycotoxins for food safety concerns. Journal of Infectious Diseases and Therapy. 3(5):241. http://dx.doi.org/10.4172/2332-0877.1000241.
Liang, P., Park, T., Yoon, J. 2016. Light scattering based detection of food pathogens. In: Renfu, L., editor. Light Scattering Technology for Food Property, Quality and Safety Assessment. Boca Raton, Florida: CRC Press. p. 429-444.
Moscetti, R., Haff, R.P., Ferri, S., Raponi, F., Monarca, D., Liang, P., Massantini, R. 2017. Real-time monitoring of organic carrot (var. Romance) during hot-air drying using near-infrared spectroscopy. Food and Bioprocess Technology. 10(11):2046.
Sanford, A.A., Isenberg, S.L., Carter, M., Mojica, M.A., Matthews, T.P., Harden, L.A., Takeoka, G.R., Thomas, J.D., Pirkle, J.L., Johnson, R.C. 2018. Quantitative HPLC-MS/MS analysis of toxins in soapberry (Sapindaceae) seeds: Methylenecyclopropylglycine and Hypoglycin A. Journal of Food Chemistry. 264:449-454. https://doi.org/10.1016/j.foodchem.2018.04.093.
Cool, L.G., Vermillion, K., Takeoka, G.R., Wang, S.C., Tantillo, D.J. 2018. Biosynthesis and conformational properties of the irregular sesquiterpenoids isothapsadiene and isothapsenol. Journal of Organic Chemistry. 83:5724-5730. https://doi.10.1021/acs.joc.8b00800.
Yi, J., Fan, Y., Zhang, Y., Yokoyama, W.H. 2017. ß-Lactoglobulin-chlorogenic acid conjugate-based nanoparticle for delivery of (-)-epigallocatechin-3-gallate. RSC Advances. 7:21366-21374. https://doi.org/10.1039/C6RA28462K.
Fan, Y., Gao, L., Yi, J., Zhang, Y., Yokoyama, W.H. 2017. Development of ß-carotene-loaded organogel-based nanoemulsion with improved in vitro and in vivo bioaccessibility. Journal of Agricultural and Food Chemistry. 65(30):6188-6194. https://doi.org/10.1021/acs.jafc.7b02125.
Zhang, Y., Fan, Y. 2017. A mutant sumo facilitates quick plasmid construction for expressing proteins with native N-termini after fusion tag removal. Journal of Molecular Biology. 59(4-5):157-167. https://doi.org/10.1007/s12033-017-9998-6.
Ban, X., Liu, Y., Zhang, Y., Gu, Z., Li, C., Cheng, L., Hong, Y., Dhoble, A., Li, Z. 2017. Thermostabilization of a thermophilic 1,4-a-glucan branching enzyme through C-terminal truncation. International Journal of Biological Macromolecules. 107(Part B):1510-1518.
Ban, X., Dhoble, A., Li, C., Zhang, Y., Gu, Z., Cheng, L., Hong, Y., Li, Z. 2017. Potassium and sodium ions enhance the activity and thermostability of 1,4-a-glucan branching enzyme from Geobacillus thermoglucosidasius in the presence of glycerol. International Journal of Biological Macromolecules. 102:712-717.
Fan, Y., Yi, J., Hua, X., Zhang, Y., Yang, R. 2017. Preparation and characterization of gellan gum microspheres containing a cold-adapted beta-galactosidase from Rahnella sp. R3. Carbohydrate Polymers. 162:10-15. https://doi.org/10.1016/j.carbpol.2017.01.033.
Shrivastava, A., Kumar, A., Thomas, J., Bhushan, G., Isenberg, S.L., Carter, M., Chhabra, M., Mittal, V., Khare, S., Sejvar, J., Dwivedi, M., Johnson, R., Pirkle, J.L., Yadav, R., Velayudhan, A., Pappanna, M., Singh, P., Somashekar, D., Pradhan, A., Goel, K., Pandey, R., Kumar, M., Kumar, S., Sharer, D., Hall, P., Graham, L., Matthews, T.P., Johnson, D., Schier, J., Chakrabarti, A., Perumal, S., Kumar, R., Valentin, L., Caldwell, K., Jarrett, J., Harden, L.A., Takeoka, G.R., Tong, S., Singh, R., Sing, R., Earhart, K., Dhariwal, A., Chauhan, L., Laserson, K., Venkatesh, S., Srikantiah, P. 2017. Association of acute toxic encephalopathy with litchi consumption in an outbreak in Muzaffarpur, India, 2014: a case-control study. The Lancet Global Health. 5(4):e458-e466. http://dx.doi.org/10.1016/S2214-109X(17)30035-9.
Zhang, Y., Fan, Y., Liu, Y., Gao, L., Yi, J. 2018. Improved chemical stability and cellular antioxidant activity of resveratrol in zein nanoparticle with bovine serum albumin-caffeic acid conjugate. Food Chemistry. 261:283-291. https://doi.org/10.1016/j.foodchem.2018.04.055.
Fan, Y., Liu, Y., Gao, L., Zhang, Y., Yi, J. 2018. Oxidative stability and in vitro digestion of menhaden oil emulsions with whey protein: effects of EGCG conjugation and interfacial cross-linking. Journal of Agricultural and Food Chemistry. 265:200-207. https://doi.org/10.1016/j.foodchem.2018.05.098.
Fan, Y., Yi, J., Zhang, Y., Yokoyama, W.H. 2017. Improved chemical stability and antiproliferative activities of curcumin-loaded nanoparticles with a chitosan chlorogenic acid conjugate. Journal of Agriculture and Food Sciences. 65:10812-10819.
