Recipient Organization
UNIVERSITY OF MAINE
(N/A)
ORONO,ME 04469
Performing Department
School of Food & Agriculture
Non Technical Summary
Small Maine farms and home-based food processors play an important role in the Maine economy. The University of Maine Food Science program partners closely with Maine food producers to improve the quality and value of a number of food products for both broad and niche markets. Some examples of such collaborations include variety trial work with a large greenhouse tomato grower; analysis of new elderberry products for the fledgling Maine elderberry industry; evaluation of nutritional quality of new potato cultivars for the fresh market; evaluation of the hops for brewing quality; and development of efficient extraction methods for the food supplement market, with a focus on chaga mushrooms.These types of collaborations encourage entrepreneurial spirit, patience and a team of professionals with broad scientific expertise. A key component of such teamwork is the ability to quickly, efficiently and accurately identify key chemical components (nutrient and bioactive) of interest in a variety of food products. These compounds are typically analyzed with sophisticated chromatographic instrumentation, the most useful of which are modern ultra high pressure chromatographs (UPLC) equipped with various detection systems. The UPLC system supported by this grant will be used to analyze a number of food products (potato, tomato, pepper, elderberry, maple syrup, hops, and chaga mushrooms) for a number of novel nutritional compounds. Analysis of new food products will enable Maine food producers to provide the highest quality foods (high in nutrients, low in naturally occurring toxins), and will help give them a competitive edge in a tough economic environment.
Animal Health Component
70%
Research Effort Categories
Basic
10%
Applied
70%
Developmental
20%
Goals / Objectives
This grant partially funds a modern UPLC system that will be used to develop and modify analytical methods to quickly and accurately measure naturally-occurring chemicals in a variety of food matrices. Recent advances in UPLC design enable more sample throughput while significantly reducing toxic solvents used for sample analysis. Although this project is funded for only one year, this UPLC system has a useful lifespan of at least ten years and will be used for many projects and will provide training for a number of graduate and undergraduate students.This project will support several project areas, including: 1. Food quality, where elderberry anthocyanin content flavor components in greenhouse-grown tomatoes and nutritional quality of potato cultivars will be measured; 2. Foods safety, where several mycotoxins associated with maple syrup, naturally occurring toxins found in potato tubers and acrylamide residues associated with French fries will be studied; and 3. To support other food-related projects, such as improving quality of Maine-grown hops, chaga mushroom chemical profiles, and capsinoid content of novel pepper fruit.
Project Methods
ObjectivesThe UPLC system represents a significant upgrade to the Food Quality and Safety Laboratory's older and largely outdated LC instruments, and will play a vital support role for a number of planned and on-going food quality and food safety projects. The instrument will also be used to support high school, undergraduate and graduate student training in a number of food-related projects.1. Food Quality1.1 Elderberries Anthocyanins and Phenolic AcidsCultivated in Europe (black elder), and found wild in North America (American elder), in recent decades, the elderberry has been intensively bred for production in North America. Several growers in Maine have taken advantage of a resurgence of interest to produce elderberry extracts and to explore new food products. Using a variety of wet chromatography techniques, we will continue to explore the stability of anthocyanins and phenolic acids under varied processing conditions and in new healthful food products, including osmotically dehydrated elderberries and the development of an elderberry kefir, a fermented milk product gaining popularity in the U.S. Product analysis of anthocyanins and phenolic acids by UPLC is critical to maximizing the phytochemical content of these new foods.1.2 Flavor Components of Greenhouse-Grown TomatoesTomatoes are a valuable U.S. crop.. Recently, a large international company began an ambitious project to produce high quality tomatoes in Maine, under a greenhouse environment. .A three year project is underway to correlate organoleptic attributes of different tomato cultivars and tomato fruit grown under a variety of environmental greenhouse conditions with chemical content. Targeted chemical analytes that influence the flavor profile include simple sugars, as well as a number of organic acids and free amino acids. UPLC will provide the resolution required to quickly and efficiently chromatographically separate these non-volatile flavor components. Data from the quantification of these compounds will be compared to organoleptic (sensory) trials in an attempt to identify chemical markers that significantly influence consumer acceptance.1.3 Nutritional Quality of New Potato CultivarsNew potato varieties are needed in the eastern U.S. to serve a wide range of markets including fresh and local food markets, chipping, French fry processing, and seed. These efforts are part of an on-going, multi-disciplinary, regionalized approach undertaken jointly by several states in the eastern U.S. and include analysis to ensure the highest nutritional value of the tubers. UPLC will be used to determine ascorbic acid and identify individual carotenoids in tubers and methods can be adapted to UPLC for faster analysis, with more sensitive detection limits. Additionally, the UPLC system will be useful for the analysis of anthocyanins in the popular blue, purple and red fleshed potato varieties.2. Food Safety2.2 Maple Syrup MycotoxinsMycotoxin contamination of the U.S. food supply has become a food safety concern in recent decades and it is estimated that there are more than 300 toxic fungal byproducts with the potential to contaminate our food supply. Maple syrup, a pasteurized commodity of important economic value to Maine, often contains a fungal mat on the product surface. For both producers and consumers the typical method of addressing this contamination is to skim this biofilm from the liquid surface and to boil the syrup before using or repackaging. Little is known about the potential for mycotoxin contamination of maple syrup, but it is well known that many mycotoxins are non-heat labile and could easily survive the boiling process. Other University of Maine researchers have isolated several Penicilium and Aspergillus spp. from mold-contaminated syrup and have used the isolates to inoculate sterile maple syrup. The UPLC system will support our efforts to identify and quantify other potential mycotoxins in maple syrup.2.3 Potato Breeding to Minimize Glycoalkaloid content and Minimize Acrylamide Formation in French FriesClassified as a possible carcinogen, acrylamide can form in certain foods during heat processing. Although the exact mechanism(s) have not been described, it is believed that acrylamide is a byproduct of the Maillard reaction and that the principal chemical contributors to this reaction in fried potato products are asparagine (a primary amine), and fructose and glucose (reducing sugars). Working with other U.S. research institutions, our role in this project is to analyze the tubers of new potato varieties for reducing sugars, organic acids, free asparagine as well as other free amino acids in an effort to reduce acrylamide levels in fried potato food products. Additionally, we are collaborating with agronomists to ascertain the effects of potassium and nitrogen fertilization regimes on free amino acid and reducing sugar content of tuber varieties used in the French fry industry. The use of UPLC will aid greatly in the separation, identification and quantification of these analytes.As part of the regional effort to develop new potato cultivars for production in the eastern U.S., (discussed in section 2.2), the proposed UPLC will also be used to screen new varieties for glycoalkaloids, a naturally occurring toxin found in potato tubers.3. Support of Other Food-Related Projects3.1 Hops alpha and beta acid profilesHops have been used for centuries to preserve and flavor beer. The key bittering agents in beer, alpha acids (humulone, cohumulone, and adhumulone) and beta acids (lupulone, colupulone, and adlupulone) have been characterized in the literature and many liquid chromatographic (LC) methods have been published detailing techniques to quantify these compounds. While most of these methods require 30-60 minutes per sample to complete, a recently published methods describe much faster LC-UV methods that will be adapted to UPLC. This technique will be used to support a collaborative project with other UMaine researchers as we assess new Maine-grown hop varieties for Maine's craft brewing industry.3.2 Chaga Mushrooms betulin and betulinic acid contentThe Chaga mushroom (Inonotus obliquus) is a saprophytic fungus found on birch trees in temperate northern climates throughout the world. The fruiting body of this fungus (black on the outside, brown on the inside) has been extracted as an aqueous tea for use as a folk medicine in Russia for many years. Recent research has focused on identifying polyphenolic fractions from Chaga, and measuring the antioxidant values of various extracts. Chaga also contains significant quantities of betulinic acid, a pentacyclic triterpenoid which has anti-tumor, antibacterial, antimalarial, anti-inflammatory, anthelmintic and antioxidant properties. Maine is a heavily forested state and these mushrooms are being harvested by several enterprises. The resolution offered by the UPLC will support enhanced separation of triterpenoids from chemically-complex chaga extracts. We will also evaluate extraction protocols to determine the best processing method to retain the highest betulin/betulinic acid concentrations for the fledgling chaga industry.3.3 Pepper capsaicinoid and capsinoid contentThe PIs have published several articles in collaboration with plant breeders detailing capsaicinoid (pungent) and capsinoid (novel,non-pungent capsaicinoid analogs) content of a large cross section of Capsicum ssp. These naturally-occurring compounds are touted for their health benefits including anti-oxidant potential, anti-inflammatory properties and decreased caloric intake in rats. Recent collaborative work by PI Perkins has resulted in a new pepper variety with high capsinoid content, recently released to the public. The requested UPLC will be used to support the development and release of additional selectively-bred Capsicum varieties containing high levels of beneficial capsinoids.