Ike E. Lynch, chief operating officer, NutraCea, El Dorado Hills, CA.

Story appeared in Food Engineering

The most nutritious portion of a kernel of rice is discarded during milling. A California processor is trying to make a business case for the byproduct by partnering with humanitarian aid groups.

When the ancient kingdoms of Southeast Asians discovered how to polish rice, the tasty new food product was a luxury only the wealthy could afford. Peasants continued to subsist on cracked rice, while the aristocracy feasted on the new dish. Before long, the seemingly well-fed nobility started dying off at an alarming rate. The cause was identified as malnutrition: by polishing away the kernel’s nutritional layers, noblemen were left with a dietary mainstay bereft of the vitamins, fats and proteins needed to sustain life.

Diet diversity prevents modern man from suffering the same fate. Still, the best parts of the rice grain continue to be discarded. Nutritional companies are trying to change that with a variety of supplements derived from rice bran, provided the bran can be stabilized. Engineer Dan McPeak developed a proprietary extrusion process to stabilize bran and, in 1989, founded RiceX. Last year, RiceX was folded into NutraCea, a specialty-products company founded by his wife, Patty McPeak. To complement the specialty products marketed by the firm and generate new cash flow, NutraCea is expanding the market for stabilized rice derivatives by partnering with humanitarian and government agencies to supply nutritional beverages in the Caribbean and Latin America. A $21.6 million joint venture with a company in the Dominican Republic last fall followed smaller deals in Guatemala, El Salvador, Jamaica and Trinidad. Malnourished children and pregnant and lactating women are the early beneficiaries, though NutraCea officials hope these demonstrations of the nutritional value and efficacy of stabilized rice bran derivatives will help create a larger market for the chafe of rice milling.

Helping to coordinate production and the outreach program is Ike E. Lynch, NutraCea’s chief operating officer. A 40-year veteran of the food industry, Lynch launched Centennial Foods Inc., a copacker of organic baby food and grain-based products, in 1989. The firm was an early licensee of Oatrim, a fat replacer made from grain byproducts and developed by George E. Inglett, a research scientist with USDA’s Agricultural Research Service in Peoria, IL. Centennial Foods was acquired in 1997 by RiceX, which was a captive supplier of stabilized rice bran to NutraCea. The two-phase process of bran stabilization and separation of nutritional derivatives now are under one umbrella.

Operators transfer bags of stabilized rice bran at NutraCea’s CA, facility. Some of the ingredient is shipped to the firm’s Dillon, MT, plant for conversion to RiceX RiSolubles®, a nutritional mix being distributed to malnourished people in Latin America and the Caribbean. Source: NutraCea.

FE: Why is rice bran wasted in the milling process?

Lynch: Once the bran is polished away from the kernel, the oil in the germ comes into contact with naturally occurring lipase enzyme and begins to oxidize, forming free fatty acids. Free fatty acids are around 2 percent when the grain is milled; within a few hours, levels rise above 5 percent, rendering it useless: it won’t pass the smell test. We use a pneumatic system to immediately deliver the bran byproduct to our facility adjacent to the mill. We then stabilize the rice brand by processing it through an extruder to deactivate the lipase enzyme and sterilize the microbial load.

Worldwide, we estimate 60 million metric tons of rice bran is wasted every year. Some of it becomes animal feed; some is burned in boilers as fuel. Most of the rest goes back to the soil as land applied fertilizer.

FE: Temperature spikes of 100°C can occur in an instant in an extruder. What is the upper limit of the process temperature?

Lynch: We don’t disclose that. However, temperature and duration both are factors in avoiding flash off of the bran’s nutritional components. We make sure energy spikes stay below a certain level and are of a very short duration so that vitamin E and other heat-sensitive nutrients aren’t driven off. Validation of those parameters is part of product specs.

FE: With which mills do you work? Lynch: Our Sacramento, CA, facility is next to the Farmers Rice Coop mill. Recently, we established a supply contract with Louisiana Mill in Mermantau, LA. They’re one of the three largest rice mills in Louisiana. We like their management, and they have access to Lake Charles and New Orleans ports. They also can use the railroad to move stabilized rice bran to our customers and our Dillon, MT, facility, where the isolation process is done.

FE: Is the isolation process similar to the one used for Z-Trim, the fat-replacer made from fiber and developed by ARS’s George Inglett (see “From the lab to the line,” Food Engineering, November 2005, p. 75)? Lynch: The processes are similar. Both hydrate the raw material in an aqueous environment. The difference is that the other process converts the fiber mechanically. Our process uses centrifugation to separate the insoluble fiber from the soluble proteins and carbohydrates. By removing the fiber, we double the nutritional value and end up with very concentrated components. We then double-drum dry each fraction to create a powder that is stable for at least 12 months.

The key to our process is what occurs at the mill. Other firms have tried to stabilize rice bran, but they typically flash off the essential oil at high temperatures and reduce the nutritional value. We’ve been able to retain the nutritional value by avoiding prolonged high-extrusion temperatures. The bran’s vitamin E is a natural preservative, and it protects against rancidity.

FE: When did NutraCea become involved in human nutrition programs in Latin America?

Lynch: We teamed up with the Christian Children’s Fund in 2002 to secure a USDA grant to supply our nutrition beverage to about 67,000 malnourished children a day in Guatemala. Malnutrition is estimated to affect 48 percent of the population. Based on that program, the El Salvador Ministry of Education asked us to conduct a school nutrition program in 2003.

The first Guatemalan program called for one serving a day of an 8-oz. cup of purified water and our RiSolubles powder. School personnel had to be trained to boil the water before combining it with the powder because of parasites in the water.

This was the only real nutritional variance on these children’s lives, and the results were just phenomenal. At the outset, 150 kids were randomly selected and evaluated. They found that 37 percent suffered from stage one or two malnutrition. After six months, none of the children were stage one, and only 5 percent were stage two.

FE: What does it cost to deliver this nutrition?

Lynch: In Guatemala, it turned out to be 17 cents a day. The delivery method is culturally driven. In the Dominican Republic, bottles are shipped with a metered amount of RiSolubles. Water is added at a school site, then the bottle is shaken and the drink served. The cost is about 22 cents a day per serving.

It's important to have a local partner. In the Dominican Republic, our partner is Food Trading Dominica SA, the largest rice milling company in the country. FTD has been in business for a number of years, so it was only natural to partner with them.

We originally planned to produce enough RiSolubles powder to supply up to 1 million servings a day, but the Dominican market is too fragmented. That’s why we entered into a supply agreement with Louisiana Rice Mill.

FE: If stabilized rice derivatives are so nutritious, how much nutrition is derived from polished rice?

Lynch: It’s mostly carbohydrates in the form of starch, which is why rice often is combined with beans to provide necessary fats and proteins. Generally, 65 percent of the nutrients are contained in the outer bran layer. Culturally, it’s crazy to eat only the white kernel.

FE: How much capacity do you have to produce stabilized rice bran derivatives?

Lynch: Our Montana plant produces enough derivatives to supply about 400,000 servings a day. The current plant expansion will double capacity, but when you consider what we’re trying to do in the Caribbean, Latin America and South America, we’re going to need additional capacity. World hunger affects 800 million people.

The raw bran coming off modern mills could feed a million people a day. We need to partner with mills processing at least 150,000 tons a year to make stabilization commercially viable.

Identifying those operations is a challenge. In India alone, there are 26,000 rice mills. Another challenge is capitalizing our advanced extrusion technology. That’s huge, but it’s manageable. Eventually we hope to partner with a food engineering firm to develop and manage a network of installations.

This article originally posted at:

Engineering R&D: Not your run of the mill rice 

Kevin T. Higgins, Senior Editor
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Kevin T.Higgins is Senior Editor of Food Engineering Magazine.

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