Ep. 03 — Better Beer Brewing, Night Pollinators and Weedy Rice

In our first episode of 2022, Nick Kordsmeier, director of Arkansas Ag Experiment Station Communications, spoke with Scott Osborn, associate professor of biological and agricultural engineering, about his improved method for carbonating beer and how it’s helping a local brewery speed up production. Then, Science Writer John Lovett tells the story of nocturnal pollinating moths and some recent research that indicates they may be more beneficial for pollinating food than previously recognized. And last, Science Editor Fred Miller, has a conversation with Nilda Burgos, Professor of Weed Physiology and Molecular Biology, about the state of weedy rice research.

Visit https://aaes.uada.edu/news for more of our stories.

Chapters

• 0:00 Introduction
• 1:12 Helping Brewers Craft a Better Brew
• 6:38 Into the Night: Shedding Light on Nocturnal Pollinators
• 10:50 The state of weedy rice research with Nilda Burgos

Transcript

[0:00] Introduction: Welcome to the Arkansas Food Farms and Forests podcast, the podcast bringing you the latest on food, fiber and forestry research from the Arkansas Agricultural Experiment station. The research arm of the University of Arkansas System Division of Agriculture.

[0:16] Nick Kordsmeier: Hello and welcome to the Arkansas Food, Farms and Forests podcast. My name is Nick Kordsmeier, and I’m the director of communications for the Arkansas Agricultural Experiment Station, the research arm of the University of Arkansas System Division of Agriculture. We’ve got another great episode lined up.

First up, I spoke with Scott Osborn, associate professor of biological and agricultural engineering, about his improved method for carbonating beer and how it’s helping a local brewery speed up production. Then, Science Writer John Lovett tells the story of nocturnal pollinating moths and some recent research that indicates they may be more beneficial for pollinating food than previously recognized. And last, our science editor, Fred Miller, has a conversation with Nilda Burgos, Professor of Weed Physiology and Molecular Biology, about the state of weedy rice research. Thanks for listening — we hope you enjoy this episode of Arkansas Food, Farms and Forests.

[Short musical interlude between segments]

[1:12] Nick Kordsmeier: Scott Osborn is using engineering to craft a better brew in Arkansas. Osborn is an associate professor in the biological and agricultural engineering department within the College of Engineering at the University of Arkansas. He also conducts research for the Arkansas Agricultural Experiment Station, the research arm of the University of Arkansas System Division of Agriculture. One of his broad research goals is to provide engineering solutions to small food processors in Arkansas and beyond. Osborn said there's been significant growth in the small food processing industry. 

[1:44] Scott Osborn: There's been such an emerging area of smaller food processors. The whole trend of buy local and produce local and some foods just have a much better-quality nutrition, etc. if you have a much shorter storage time, they're cheaper to make. They're cheaper to store and because you don't have to ship them very far. And so that's led to a tremendous growth in the area of very small-scale food processors.

[2:09] Nick Kordsmeier: In Arkansas, the craft brewing industry is one example of this growth of small food processing. The number of licensed breweries in Arkansas has increased from six in 2011 to 43 in 2020, according to the Brewers Association, a national organization based in Boulder, Colorado.

Osborn saw craft brewing as one industry that could benefit from some engineering. Craft breweries rely on small batch brewing techniques that don't allow for the purchase of highly engineered large scale brewing equipment common in national breweries. Osborn said one process in particular showed promise for improvement -- carbonation.

[2:47] Scott Osborn: The problem with the current carbonation method is that you can waste CO2 gas and it takes a long time to do it. 

[2:56] Nick Kordsmeier: Carbonation is typically one of the last steps in the brewing process. When a batch is finished fermenting, it makes its way to large stainless steel tanks called “brite” tanks. These are vessels where carbonation takes place before packaging, Osborn said. Carbon dioxide is introduced through a device called a carb stone that releases tiny bubbles of carbon dioxide into the beer. This method, called forced carbonation, is not 100% efficient, however. And much of the gas passes through the beer without dissolving into the liquid.

[3:26] Scott Osborn: Any bubble that leaves that, that liquid level is wasted, and it goes out into the atmosphere, which is a greenhouse gas and it's a wasted cost.

[3:34] Nick Kordsmeier: Osborn said the escaping carbon dioxide bubbles also carry some of the flavors of the beer with it, also known as stripping the nose, referring to the lost aromatic compounds carried away by the escaping gas. To combat these problems, Osborn invented a device and process that does away with the carbon dioxide bubbles. In Osborn's new method, beer is pumped out of the bright tank into a high-pressure tank that he calls the “saturation tank.” Beer is injected into the top of the saturation tank and comes into contact with a pressurized carbon dioxide gas. 

[4:06] Scott Osborn: The concentration of CO2 in that gas is much, much higher than it would be at the lower pressure in the “brite tank.” That more efficiently dissolves the gas into the liquid. 

[4:17] Nick Kordsmeier: So the beer and the saturation tank has a much higher concentration of carbon dioxide.

[4:22] Scott Osborn: Then we continuously pump this high concentration of dissolved CO2 beer, or beverage, back into the brite tank, and it mixes in the bright tank, so it's a continuous recirculating process. You don't have bubbles, you don't strip out the nose, you save CO2 costs, and it's faster. 

[4:38] Nick Kordsmeier: Osborn named his invention Carbo Rock-it. 

[4:40] Scott Osborn: If you see the equipment, it looks like a rocket, but instead of “rocket” we spelled R-O-C-K dash I-T like “rock it!” because it goes so fast.

[04:49] Nick Kordsmeier: Core Brewing and Distillery Company, a craft brewery in Springdale, Arkansas, has been integral in helping Osborn test and perfect his invention. 

[4:58] Scott Osborn: We've been partnering with Core Brewing and Distilling Company in Springdale for four or five years, built the first prototype out of PVC pipe and, you know, duct tape and zip ties and all that stuff. And they would give me waste beer that they weren't using, and I would test it on that. 

[5:12] Nick Kordsmeier: Through funding from the University of Arkansas' Chancellors Commercialization Fund, supported by the Walton Family Foundation, Osborn was able to build a full-scale food grade unit to test at Core. The partnership has been mutually beneficial, Osborn said. 

[5:26] Scott Osborn: Through that process, we got a lot of feedback from their operators. You know, “we like to do it this way,” and “this is difficult to reach from here” and just really practical feedback on how to improve it.

[5:38] Nick Kordsmeier: After several rounds of initial testing, Core incorporated the “carbo rock-it” into their full time production process for their brand of spiked seltzer water.

[5:46] Scott Osborn: It worked great. We reduced their carbonation time from 72 hours down to six hours.

[5:53] Nick Kordsmeier: Osborn said the next steps in his research are automation and evaluation of flavor. He's using another grant from the Chancellor's Commercialization Fund to automate the carbo rocket and is planning to conduct a blind taste panel at the Experiment Station Sensory Science Center to determine if there's a statistically significant difference in the flavor of beer produced using the new carbonation method. Osborn said he wants to help small food processors perfect their craft while maximizing profitability. 

[6:19] Scott Osborn: What we're talking about is not changing their art and what they do, but supporting it and allowing them to do that, but yet maximize their profits, maximize the consistency and quality, but yet still allow them space to do their art.

[Short musical interlude between segments]

[6:38] John Lovett: For millions of years, there's been a night shift at work pollinating flowering plants and fruit trees, but only recently have they started to get a little credit for their contributions to agriculture. Stephen Robertson, a recent University of Arkansas Ph.D. graduate from the Department of Entomology and Plant Pathology, conducted a three-year study within the Arkansas Agricultural Experiment Station on nocturnal pollinators. He found that moths can provide just as much pollination of apple trees at night as bees do during the day. It all started in Fayetteville back in the spring of 2016, when Robertson was working on a study to make insect traps in peaches more efficient.

[7:12] John Lovett: When he started catching more moths during the period of fruit bloom, he decided to investigate. Robertson and his co-investigators set up an experiment to determine if moths had an impact on pollination of apple trees. His experiment compared the number of different types of pollinators observed under three different conditions: Daytime only, nighttime only and 24-hour open pollination. The purpose of the daytime only and nighttime only treatments was to exclude moths during the day and bees during the night. Initial results from the first season's experiment suggested the importance of moths as pollinators and led Robertson to continue the experiment for two more years.

[7:48] John Lovett: Ashley Dowling, professor of entomology for the Arkansas Agricultural Experiment Station, the research arm of the University of Arkansas System Division of Agriculture, said the night pollinator study provides further evidence that native pollinators offer an alternative to honeybees for fruit growers. And it makes sense, he said. They've been around flowering plants a lot longer than bees.

[8:07] Ashley Dowling: So, flowering plants really started to evolve, diversify, 140 million years ago. And at that point, we didn't really have the diversity of bees. Bees who came along later. So, there was something obviously pollinating before the bees came and it was most likely moths. We know that maybe beetles might have been some of the earliest pollinators, but moths quickly filled that niche and obviously lepidoptera, the moths and butterflies, their caterpillars are feeding on plants. And so as flowering plants diversified, moths and butterflies also diversified as well because there was just this abundant food source for their larva, for their caterpillars. 

[8:45] John Lovett: In effect, moths and other night pollinators have been the unsung heroes of pollination, and entomology is still catching up on all that they can do, Robertson said. Robertson and Dowling said other studies are also showing the importance of moths to food crops and how they may actually be the most important pollinators as a group. 

[9:02] Ashley Dowling: You know, it's just one of those things. I think the more we learn about the native insects around us and what they contribute to agriculture, that sort of helps pull us away from this system of having to rely upon a single thing like honeybees to do it. And so just having more options out there is beneficial to everybody. 

[9:21] John Lovett: For apples, at least, the case is pretty clear. If you own an apple orchard, all you really need is native pollinators, Dowling said. The added cost of managing honeybees for some crops may not be necessary if further research shows that native pollinators could do the job just as well. 

[9:35] Ashley Dowling: You know, knowing that a lot of our native pollinators can actually do a good job, and pollinators that may already be there in your fields, around your fields, you know, knowing that they might be a sufficient replacement to honeybees, you know, really helps us looking forward. You know, if we keep experiencing problems with honeybees, then you know, we know we have options. And you know, it also may change our approaches to things too that maybe not so much focus on honeybees.

[9:55] Ashley Dowling: And, you know, maybe see what these nocturnal pollinators can do and maybe how do we increase the populations of these nocturnal pollinators? Can we do things around the fields having native vegetation and things to sort of increase their populations where than we just have a natural population that could come in and do the job for us.

[10:18] Ashley Dowling: And so, Stephen's study sort of lays the groundwork for that, sort of indicates that, you know, at least for certain things, certain plants, there may be a whole suite of nocturnal pollinators that will do the job for us.

[10:33] John Lovett: Project partners in this study included Neel Joshi, associate professor of entomology for the experiment station, and Erica Westerman, assistant professor in the University of Arkansas Department of Biological Sciences. 

[Short musical interlude between segments]

[10:50] Fred Miller: Red rice in the field was a problem for rice growers, but at least it was easy to spot. Now, after years of outcrossing with cultivated rice varieties, red rice has become weedy rice that appears in a spectrum of hues, some of which can blend in nicely with the crop. Dr. Nilda Burgos, professor of weed physiology and molecular biology for the Arkansas Agricultural Experiment station, has been working on the problem of red rice for years and now thinks of it in terms of varying hues of weedy rice. Dr. Burgos is here with us today to talk about this weedy problem and how rice growers can stay on top of it. Welcome, Dr. Burgos. Appreciate you being with us today and talking about weedy rice. What is weedy rice? 

[11:33] Nilda Burgos: So it is a weedy relative of rice. Historically, we're calling these plants weedy plants, red rice, because these weedy versions of the crop have red colored seed so, red colored kernel. This weedy rice or red rice, as we used to call it, actually has descended from the same ancestors as the crop that we grow. Essentially, we can say that weedy rice is even more closely related to the wild relative of rice and so the crop, though we grow, has been bred for years, for decades, centuries from, you know, the first people who had cultured rice from the wild. So rice comes from the wild. And so as they have selected across generations for the type of plant that can give them better grain, more grain or more palatable grain, then in this process, we have also arrived at the point where we have weedy versions of this cultivated rice. So basically, this weedy rice or red rice coexist with rice. So as we culture rice, normally we will see this. 

[12:52] Fred Miller: You don't call it red rice anymore because it's not always red. Is that right? 

[12:56] Nilda Burgos: Yes, it used to be that we call them red. Globally, they are called red rice because the weedy relative of rice, the parent of rice, actually has red colored seed. So the seed may be so tiny, but they're dark. No, not really. Even red kind of dark, almost purple. And the now you mentioned. Now what are we calling them? Now we're calling them weedy rice, because not all of them have red pericarp anymore because of just because of natural hybridization between the rice and the red rice. And then now we have a mixture of weedy types of rice.

[13:36] Fred Miller: That's from some of the cultivated varieties that have crossed with the weedy varieties to create these intermediate shades?

[13:44] Nilda Burgos: Yes, because they are essentially the same, you know, the same genus, the same species. One is just our cushion crop and the other is the weed. Right? And so then so then they're still genetically compatible, so they hybridized in nature. Now they're hybridization rate is low because rice is primarily self-pollinated. And so they hybridized background levels, we say, and we don't even hardly notice. We don't really notice it. You know, in the field until we pay close attention and then and then now we've arrived at this point where we have many more kinds of weedy rice because now we are in the era of adopting herbicide resistant rice technology. Now we can use herbicide to kill weedy rice and red rice without killing the rice. Well in the process of adopting this, well, the natural hybridization still happens. And so but because of the resistance trait of the rice cultivars now, so then that resistant strain gets passed on to the offspring about grasses.

[14:58] Fred Miller: And you're talking about weeds now that are beginning to develop tolerance to the herbicide.

[15:04] Nilda Burgos: Right. So now we're talking about weedy rice or red rice that has received pollen from the herbicide resistant rice. And then and then now that weedy rice, weedy plant would carry that trait.

[15:19] Fred Miller: Talk to me a little bit about the problem of having weeds in the rice for the farmer. You know, we talked about the issues they have at harvest, you know, differences of maturity, differences in other differences between the weedy rice and the cultivated rice that present issues for the farmer. Why is it a problem for them?

[15:39] Nilda Burgos: The weedy rice populations that we have now, some of them would have grains or kernels that are almost the same size or shape as the cultivar. So some of them now look like they're also long grain. These grains from the weedy plants do not necessarily have the same good quality as the rice crop. What I mean by that is there's starch composition somehow is different, which would actually impact its cooking quality and maybe even taste. And then also fissuring, the tendency to crack would also differ from the rice cultivar. So there are actually physical and chemical traits of the grain that that matter to the consumer. 

[16:33] Fred Miller: You said there was also an issue with maturity if it matures earlier or later than cultivated variety.

[16:39] Nilda Burgos: So actually, that is one factor that would have a significant effect on grain quality. So if it is harvested to dry, then the grain could be brittle. Right. And so and then if it is harvested too young, then the physiological processes required for a grain to mature properly and have its proper chemical composition and all that, then that is compromised. So then so then we would also end up with easily broken grains, for example, because it is too-young rice, not properly filled, not properly hardened and it alters the starch quality of rice, of course. Then we will encounter all sorts of types of grains that could be harvested together with the rice. So we will have we could potentially have weedy rice grains that are that are too moist or weedy rice grains that are that are too dry. So we just need to be aware that whatever we do, we don't want to help the weedy plants persist in the field. 

[17:45] Fred Miller: Not to mention, I mean, if you get a lot of weedy rice in with your cultivated rice, they're competing for resources.

[17:51] Nilda Burgos: That is for sure right. The productivity of this weedy plant, it sucks up a lot of nutrients, sucks up 60% of nitrogen that we apply. It sucks up all of this, it produces, it can produce a lot of biomass but the proportion of grain that it can produce per leaf biomass, let's say that it produces, that is not as high as the proportion that are cultivated rice can produce. Now what we're doing is we're just feeding it with nutrients. You know, it sucks up the water source of nutrients. It's not productive. It's not as productive as the rice cultivar that is being planted. And so that's the problem. So then so then the cultivar suffers because it's been robbed by the weed of a lot of the nutrients, but then the weed that is using it is not really producing, you know, to contribute to the productivity of the land.

[18:53] Fred Miller: So it sounds like you're reducing the yield of your desired cultivated rice because a lot of those resources are being taken up by the weedy rice, which is undesirable quality and also maybe not as productive as the cultivated rice. And so the cultivated rice is going hungry and maybe not being as productive. Your yields are lower, right? 

[19:12] Nilda Burgos: Right. So at the certain level, when we surveyed these to assess the potential impact or effect of volunteer plants or weedy plants on the rice crop yield, we arrived at an estimate that if the level of infestation of volunteers or weedy plants kind of approaches 10%, then we start seeing some quality effects, some yield effects. And then you can imagine if we continue to have higher infestation from that, then we would feel, you know, really a significant a significant impact of the infestation of volunteer rice or weedy rice on the crop, whether it's going to be on grain yield or quality.

[20:05] Fred Miller: And hopefully before it gets to 10% the farmer has noticed it and is taking some action to try to correct it. 

[20:13] Nilda Burgos: Yeah. And also, if the majority of the plants are still red seeded, then of course, when they get that to the mill, then of course they will already see the effect of that from what normally happens from the price reduction if you have a lot. Hopefully, we don't get into that situation anymore that we have that level of infestation the farmer will incur losses in price.

[20:41] Fred Miller: You had mentioned to me earlier that you were working on an article regarding a survey of weedy rice in Arkansas?

[20:50] Nilda Burgos: Oh, that it's we've already published that. So that's published in the Weed Science Journal. So it's a special issue and really rise across the globe, across the world. The goal is to see how we are doing globally in terms of managing the weedy rice problem or how, how intense or how bad, the weedy rice problem is outside of the U.S.

[21:20] Fred Miller: Speaking of managing problems, I mean, what kind of countermeasures can farmers take? What actions can they take to reduce the issues? We talk about zero tolerance of weeds, for example, but what sorts of things can they do? 

[21:34] Nilda Burgos: One of the things, of course, is that, OK, we say we should just not allow any weedy rice to remain in the field. And so that's what we're calling zero tolerance. If we do not allow anything to remain in the field any time, then there isn't any problem with outcrossing. There isn't going to be any problem with more seed deposit into the weeds seed bank. So that's one. So other things would be in the surveys that have been done on rice like surveys done by Dr. Norsworthy and our team. It would always come up that the best recourse to drive the population of red rice back down is to plant another crop. And the other crop the growers plant normally is soybean, but then they could also plant corn or others. And still having that cultural practice, the growers still adapted very quickly the technology of herbicide resistant rice when it came, because this one is a very big supplement to crop rotation, because if you rotate and then you diminish the rice population and then you go back to rice, there is red rice there. Well, if you have herbicide resistant rice technology, then that is great. Then you can spray this plant herbicide resistant rice, spray this crop, kill the rice. So if only the growers can kind of always integrate this. Rotate the rice and then use the herbicide resistant rice technology with that. 

[23:24] Fred Miller: And I guess as long as you're trying to keep these plants from existing in your field, don't forget the edges of the field right in the ditches.

[23:32] Nilda Burgos: That is so true. So yes, we mentioned that, OK, we have removed everything from the field. And then we say now we're confident there is no hybridization that's going on because there are no weedy rice in the field. Well, but if they are, if there are weedy rice, the edges of the field, the ditch banks, irrigation ditches. These are catchers of pollen from the field. 

[23:58] Fred Miller: Well, Dr. Burgos, I appreciate your time. I know that there's just a ton more that we could talk about in this area. You've worked on it a long time. I think we will finish up here and I appreciate your time. Thank you for being with us today. 

[24:11] Nilda Burgos: Oh, thank you. Thank you, Fred, for the time also. 

[Short musical interlude between segments]

[24:15] Nick Kordsmeier: A big thank you to all of our guests for joining us on this episode of Arkansas Food Farms and Forests. If you'd like to stay in the loop with the Arkansas Ag Experiment station, please subscribe to this podcast and check out our news website. In January, we announced the release of three new rice varieties. Shared the first episode of a new agribusiness podcast, Relevant Risk from the Fryer Price Risk Management Center of Excellence, and highlighted one of our faculty, Jen Woo Kim, for his induction as a fellow of the Institute of Electrical and Electronics Engineers. These stories and more can be found on our website, AAES.UADA.EDU/NEWS. We'll be back next month with more great science and research stories from the Arkansas Ag Experiment Station. Thanks again for listening to this episode of Arkansas Food Farms and Forests.

[25:05] Conclusion: The Arkansas Food Farms and Forests podcast is produced by the Arkansas Agricultural Experiment Station, the research arm of the University of Arkansas System Division of Agriculture. Visit AAES.UADA.EDU for more information.