1525 CLEMENT ST #2
SAN FRANCISCO,CA 94118
Non Technical Summary
With the rise in craft brewing has come an increase in waste produced during the brewing process; roughly a pound of edible and nutritious grain is created for every six pack of brewed beer. ReGrained is a mission-driven food-tech company that is transforming brewing waste and byproducts into value-added tasty ingredients and products. In partnership with the USDA ARS, ReGrained has developed patent-pending technology to rescue, process, and stabilize wet food manufacturing byproducts and create ingredients. SuperGrain+, produced from brewery byproduct ("brewers' spent grain" or BSG), is the company's initial development focus before moving onto additional food and beverage industry byproduct streams. As a comparative analog, ReGrained's seeks to do for the brewing industry what whey did for cheese; once a valueless waste stream, now a food industry staple. Tens of billions of pounds if BSG is generated per annum, in the United States alone. Traditionally, breweries sell or donate this grain to farmers for use as animal feed, because despite its impressive nutritional profile, it spoils quickly. ReGrained's technology solution enables food-grade commercialization of this resource as an ingredient. This novel processing enables it to be sustainably introduced as a nutritionally valuable and delicious ingredient for human consumption while extending the life cycle and value of the grain and putting waste produced by the brewing industry to the highest use. Earlier research has shown strong potential for being recycled and used as a low cost source of fiber, proteins and other nutrients that may provide a number of benefits when incorporated into human diets such as a prevention of certain diseases including cancer, gastrointestinal disorders, diabetics and coronary heart disease. This Phase I grant proposal will conduct animal studies in support of a future Phase II human clinical trial to determine the efficacy of dried BSG flours on amelioration of insulin resistance, promotion of beneficial gut microflora, assistance in weight management, and reduction of biomarkers of obesity related metabolic diseases. The data from Phase I will support marketing of BSG products, as our findings will allow for efficient processing and implementation of BSG at scale. After demonstrating significant health benefits, human studies in Phase II will support successful commercialization of dried BSG flour and derived new products. If successful, ReGrained's processing facilities have the potential of creating more jobs in a new industry that could improve the health of the American public by producing an ingredient that is high in fiber, proteins and phenolics/antioxidants. In addition to improving human health, the processing of BSG into nutritious ingredients will also provide more sustainable options to decrease waste disposal in landfills.
Animal Health Component
Research Effort Categories
Goals / Objectives
The broad goal of this project is to validate the promising indicators that incorporating dried "Brewer's Spent Grains" (BSG) flours as a functional ingredient in baked foods can improve health outcomes.Specifically:Can consuming BSG be effective in the management of diabetes?Can consuming BSG be effective in the management of hypertension?Can consuming BSG be effective in lowering cholesterol?What impact does the BSG's fiber content have on gut health?What impact can the BSG's phenolic compounds have as anti-carcinogens?What impact can the BSG's phenolic compounds have as antioxidants?What impact can the BSG's phenolic compounds have as anti-inflammatory response?In collaboration with USDA, ARS, Western Regional Research Center, we will validate the effects of feeding baked snacks with different levels of dried BSG flour on plasma and liver lipids, and weight gains. The technical objective of this research is to determine the dose and composition of dried BSG flour added to baked snacks that produce observable physiological effects in animal models to proceed with a future human study. We intend to use obese animals fed high fat diets to identify bioactivity of phenolic acids and/or fiber fractions, determine possible mechanisms of action, as well as characterize the effect of dried BSG flour on plasma lipids, weight gain, inflammatory response, and gut microbiota.In this project we will investigate the benefits of BSG flours on amelioration of insulin resistance (a precursor of diabetes) and promotion of beneficial gut microflora growth. The results of these small animal experiments can be used as indicators of potential health benefits in humans and as justification for future human clinical trials.Objective 1: Characterize a variety of distinct types of BSG supplied by Northern California microbreweries for polyphenolic content, proteins and fibers. Fresh BSG will be dried using a proprietary patent-pending processand milled to produce dried BSG flours and physical, chemical and nutritional properties of dried BSG flours evaluated and related to potential health benefits.Objective 2: Validate a cholesterol lowering effect of dried BSG flour at doses comparable to human studies in diet-induced obese hamsters on high fat diets. We will use obese and glucose intolerant animals to model the overweight and obese human populations of interest. These animals will be fed baked snacks with 5-20 % dried BSG flour added in formulations. We will study the effects of fibers, proteins and phenolic content in dried BSG flour to weight gains (losses), plasma and liver cholesterol and triglycerides.Objective 3: Determine the effects of BSG fiber and phenolic compounds on intestinal permeability, intestinal barrier protein expression and inflammation due to intestinal permeability of bacterial lipolysaccharides (LPS). Dried BSG flour contains significant amounts of dietary fiber and non-extractable phenolics which are classes of compounds known to be metabolized by gut microbiota into absorbable and potentially bioactive compounds. The contribution of the non-extractable phenols to improve adverse physiological characteristics of obesity described in Objective 2 will thus be evaluated in terms of the microbiome.
Objective 1: Fresh BSG of known formulation and brewing conditions will be obtained from Bay Area micro-breweries and processed. The whole dried BSG will be two-staged milled in a hammer mill to pass through a 200 µm screen. Proximate analysis (moisture, protein, dietary fiber, ash, water, carbohydrate, fat) as well as physical and other chemical analysis will be determined by standard methods. Dried BSG phenolic composition will be determined by HPLC.Objective 2: The animal studies will be conducted at Western Regional Research Center. Male golden Syrian hamsters, 170 @ 40-50 g, will be fed a 45% fat calorie diet (HF) to induce obesity and insulin resistance. One group of 8 animals will be kept on rodent chow for the duration of the study as a low-fat reference. After 6 weeks fasting, blood glucose (FBG) will be compared to animals on chow. When the FBG of at least 70% on the animals on the HF diet are higher than those on the rodent chow diet, the animals will be randomized and fed the BSG derived diets. If insufficient animals have high FBG animals will continue with the HF diet for two more weeks and tested again until at least 112 hamsters have high FBG. Sixteen hamsters will be placed on each of 4 levels of addition of dried BSG in a baked snack formulation (5, 10, 15 and 20 %) for a total of 112 animals. The HF diets will contain 8% butterfat, 10% corn oil, 2% fish oil, 0.1% cholesterol, 20% casein, methionine, choline, bitartrate, mineral mix, vitamin mix, and corn starch. Animals will be housed individually, have free access to feed and water and kept in constant temperature and humidity cages. Animals will be weighed weekly and feed intake determined twice each week. Eight hamsters from each BSG baked snack derived diet (56) will be sacrificed at 10 and 20 weeks. The hamsters on chow will be sacrificed at 20 weeks only. Feces will be collected for 3 days prior to the end of 10 and 20 weeks feeding. The protocol has been approved by the Animal Care and Use Committee of the Western Regional Research Center, Albany, CA.At the end of the feeding periods, hamsters will be anesthesized using isofluorane:oxygen and blood collected by heart puncture. Liver, epididymal adipose, intestine and muscle will be quickly removed, weighed and placed in liquid nitrogen. Plasma lipoprotein cholesterol, fat content and lipid analysis of liver, fat content and lipid analysis of feces, and gene expression of genes related to fat, cholesterol, and bile acid metabolism, inflammatory genes, adipokines in liver, adipose, and intestine by PCR will be analyzed. Tissue analysis will be conducted at WRRC, Albany, CA and Department of Nutrition, UC, Davis, CA.Objective 3: BSG dried flour will be extracted with 20% aqueous ethanol at 80 oC and the extract and residue (non-extractable polyphenols and fiber) will be fed to mice on 35% fat calorie diets as described in Objective 2. Concentrations of plasma lipids and other physiological characteristics of mice fed the extract and residue will be compared to the whole BSG dried flour diet provided to hamsters. Mice either previously fed rodent chow (normal weight mice) or high fat diet (diet induced obese) will be fed a high fat (45% fat calorie) diet supplemented with 10% defatted BSG dried flour. A group of mice will be kept continuously on rodent chow. At 6 weeks FITC conjugated dextran will be introduced via gavage and inter-peritoneal samples examined to determine intestinal permeability. Cecal and colonic content will be collected at sacrifice. Feces will be collected prior to end of the feeding period. Digesta and feces will be defatted, extracted with methanol: water:H3PO4 and their composition analyzed for hydroxycinnamic acids by HPLC. Mice will be sacrificed after 8 weeks on the high fat diet. Liver, adipose, blood feces, duodenum, jejunum, ileum, and cecum will be collected. Contents of the cecum will also be collected. Expression of genes coding for intestinal tight junction proteins ZO-1 and occludin will be determined by RT-PCR. Gut microbiota profile of the cecal, large intestine and fecal contents will be determined by qPCR microbial DNA analysis.