EP 5: From food waste to pet food

In this episode, Dr. Anna Sutton and co-host Amanda discuss an interesting topic: the use of food waste in pet food.

While we all strive to minimise our own food waste, the food industry faces a different kind of challenge - dealing with vast amounts of waste on an industrial scale. Today, we dive into the innovative ways one leading company, Kagome, is turning food waste, specifically carrot pulp and tomato skin and seed, into valuable ingredients for pet food. 

Dr. Sutton also discusses the benefits of chia seeds in dog diets and gives you your own carrot and tomato food hack.


Have a listen to the show, but if you’re more of a reader, here's the transcript:

[00:00:00] ANNA: Welcome to the Pet Nutrition Show. I'm Dr. Anna Sutton. And with my co host, Amanda, we'll be talking nutrition, sustainable pet food, and food hacks you can do at home. Now, today, we're talking about the use of food waste in pet food, but not the kind of food waste you and I are making. This is the kind that's produced on an industrial scale.

[00:00:21] ANNA: And I mean, In, by the truckload. Now, in the old days, we used to think of this, uh, as just as waste, but today the leading companies are seeing what else can be done with it.

[00:00:32] TROY: We grow about 30, 000 tonnes of carrots. By doing that, we created a 7, 500 ton waste problem with the carrot pulp that was left over.

[00:00:41] , So we harvest around 220, 000 tons of tomato, and, we actually are quite good at, reworking our waste into products like tomato paste and so forth, but we have about a 5, 000 ton problem with, uh, tomato skin and seed.

[00:00:55] AMANDA: That was Troy Hugdson. And our interview with him is coming up in a moment. [00:01:00] But first it's time for Q and a.

[00:01:03] AMANDA: Q&A]

[00:01:04] AMANDA: Today's question comes from an Instagram post that someone sent me during the week. And the post was encouraging people to give their dogs half a teaspoon of chia seeds every day. And it said that if you did that, five good things would happen. So I'm going to go through the five things and you're going to tell me what you think.

[00:01:25] AMANDA: And the first is chia seeds help dogs manage weight because the fiber makes them feel full.

[00:01:31] ANNA: Ah, that's a That's a good one, Amanda. It's probably true because chia seeds have a truckload of fiber and actually if you add water to them, you'll see they swell up hugely and they do the same thing in your dog's stomach and they activate then stretch receptors that tell your dog, hopefully, please stop eating now or don't eat quite so much.

[00:01:49] ANNA: So, so a yes to that one. Not sure if they work with my lab.

[00:01:56] AMANDA: Number two, chia seeds contain good stuff [00:02:00] that makes their skin healthy and their coat shiny. What could that good stuff be?

[00:02:05] ANNA: Well, I think they're talking about the omega 3 fatty acids in, in chia seeds. Chia seeds are very rich in ALA, which is a type of omega 3 fatty acid. That's great for a lot of things, including keeping your skin healthy, uh, and your coat shiny. Now there is a caveat to that because ALA needs to be, uh, converted into.

[00:02:27] ANNA: DHA and EPA, uh, longer chain omega free fatty acids to really be effective. And in that regard, you may be better just going for the D, the DHA and the EPA that you can get from fish oil. But, but Chia seeds are still a great source.

[00:02:46] AMANDA: Just not quite so efficient. And perhaps that might be part of the same answer to number three, which is that chia seeds can also help with joint mobility.

[00:02:55] ANNA: Yes, that's the same thing. So with, uh, joint mobility and [00:03:00] inflammation, omega 3 fatty acids, particularly DHA and EPA can help manage inflammation. Um, so what they're saying here is the, the omega 3s in chia seeds may help with joint inflammation. That's true, but only after they've been converted into DHA and EPA, just like before.

[00:03:21] AMANDA: So, if you wanted a more efficient method, you might have an algae based DHA or a fish oil.

[00:03:26] ANNA: Yeah, that, that's right. That's right.

[00:03:30] AMANDA: Now, number four is that chia seeds can help keep a dog's blood sugar level steady, which helps with dogs that have got diabetes.

[00:03:38] ANNA: Yeah, that's an interesting one because there's quite a lot of studies in this area in humans. So chia seeds are very rich in fiber. We've mentioned that already. They're rich in the insoluble fiber that acts like a broom, but also the soluble fiber that acts a little bit like a gel and effectively forms a gel coating along the GI tract that [00:04:00] can slow down the absorption of certain nutrients, including sugars.

[00:04:04] ANNA: And this can help stabilize Uh, sugar levels, at least in humans. So a yes to that one.

[00:04:10] AMANDA: Eh, okay. And then number five is it helps digestion. The fibre makes it easier to digest food and keeps their tummies happy.

[00:04:21] ANNA: Well, I think this is a maybe, and I think it's, I probably would have put it a slightly different way. So chia seeds. As I've mentioned, do contain fibers and part of that fiber is very fermentable. So what that means is that that fermentable portion helps feed the cells in the colon, uh, in the, um, in your dog's gut, the bacteria, sorry, in your dog's gut, which generate short chain fatty acids that feed various other cells and do all sorts of other things.

[00:04:54] ANNA: Uh, those microbes, those bacteria. Also are able to do [00:05:00] some nutrient digestion. It's not the main, main role, but they certainly are. So the more you have them in theory, you know, you, you can help digestion that way.

[00:05:12] AMANDA: So, in summary, generally good, but are there any downsides?

[00:05:17] ANNA: Uh, yes. Look, with anything, there's always a bit of a dark side, isn't there? Look, chia seeds are particularly rich in phytates and oxalates, and both these interfere with nutrients, absorptions of various minerals and so forth. However, in, in real life. You're probably only going to give your dog, as they recommend here, half a teaspoon to a tablespoon or so a day of chia seeds.

[00:05:42] ANNA: So, in the context of a healthy diet, uh, chia seeds are certainly a great thing to add. And they're probably not going to do any harm in that regard.

[00:05:54] AMANDA: Our guest is a biochemist by degree and a food expert by career, with [00:06:00] stints at Bega Cheese, Fonterra, and the CSIRO. He's now the marketing lead with Kagome, a company you might never have heard of, one that was founded in Japan in 1899. And since those early beginnings in Japan, specializing in Wait for it, tomato sauce.

[00:06:17] AMANDA: Kagome has gone on to be a global leader in sauce creation. Kagome Australia is Australia's largest tomato processor, but they also process carrots, beetroot, and apple. Troy Hugdson. Welcome.

[00:06:30] TROY: yes. Thank you very much. It's nice to be here.

[00:06:33] AMANDA: Great. Now, aside from producing pizza, pasta, and a myriad of other sources, Kagome also produces something called Ninjin fibre carrot powder, which comes from carrot juice pulp. You should, you think I'd be able to say that because we actually use it in my company. Now, can you take us back to the start of the Ninjin fibre project?

[00:06:53] AMANDA: When was it? And just how much carrot juice were you actually pulping at the time?

[00:06:59] TROY: [00:07:00] So it goes back to 2018 and, uh, we grow about 30, 000 tonnes of carrots. And, um, that went into making carrot concentrate, which we shipped to Japan. Uh, but we also created, by doing that, we created a 7, 500 ton waste problem with the carrot pulp that was left over.

[00:07:17] AMANDA: Just before you go on, so help me visualize 30, 000 tons,

[00:07:23] TROY: Uh, 30, 000 tons, if you put it into a, uh, 20 ton truck, um, so carrying 20 tons, it would equate to,

[00:07:31] AMANDA: a lot of trucks.

[00:07:32] 1500 of them. In fact,

[00:07:35] AMANDA: And so the waste was seven and a half thousand tons out of 30, 000 tons. Is that right?

[00:07:41] TROY: Yeah, 7, 500 tonnes out of 30, 000, yep.

[00:07:43] AMANDA: Okay, which is a fair proportion.

[00:07:46] TROY: It was very large, yes.

[00:07:48] AMANDA: And so why did you want to do something with it? Was it a cost to you to get rid of that waste or?

[00:07:55] TROY: It does cost us to remove the waste, that was one point. Uh, the other point was, was that, um, there was some [00:08:00] interesting, there was some carrot fibres that were made overseas. Um, and, uh, we thought that we might be able to do something around that. Uh, one of the key challenges was to actually do the drying.

[00:08:11] TROY: Um, and that's where we actually did a project and actually look for a, uh, a specific dry, not just a drum dryer or a freeze dryer, um, or air dried as they might do in some, in some parts of the world. Um, so we actually developed a purpose built dry for, uh, turning. Carrot pulp into carrot powder.

[00:08:31] AMANDA: And so if it's not a drum dryer, freeze dryer, or an air dryer, what kind of dryer is it? Can you tell us a little bit more? I understand that it's probably proprietary technology, but can you give us a bit more of an insight into how it does dry?

[00:08:44] TROY: It's probably under heat and vacuum. So, um, for, um, for lyngen fiber, uh, the, basically the carrot pulp comes in, uh, it's then heated and then the, uh, the dry particles go to the top of the dryer and then goes out into the, uh,[00:09:00]

[00:09:01] AMANDA: And who did you work with to develop that technology? That wasn't done entirely in house, was it?

[00:09:06] TROY: no, no. It was, we worked with a manufacturer who did a lot of, uh, drying in the mineral space. Um, and one of the challenges with Ninjin Fibre was it was 90 percent moisture. And that made it very, very difficult to dry. So our, uh, lead technologist, uh, guy by the name of Ian Bradney found one in Perth. Uh, we went over there.

[00:09:25] TROY: It was actually for mining. Uh, we threw some of the carrot into it, and lo and behold, it dried it. It

[00:09:30] AMANDA: Now, one of the partners that you worked with early on was Monash University. Talk to us about how they helped you get off the starting blocks with, uh, Ninjin Fibre.

[00:09:42] TROY: We're very, very lucky that we came across Professor Victoria Haratos. Uh, she's an expert in her field, uh, and with some funding from the Victorian government, also the federal government in terms of FIAL, uh, we're able to do an initial research study, uh, that didn't cost the earth to find out what we actually had or what we could have, um, in [00:10:00] terms of our, uh, carrot pulp and what products we could make from there.

[00:10:03] TROY: And she came back with a recommendation of around 10 opportunities. Uh, that we then work together to scale from a difficulty to an ease of manufacture, uh, to then attractive market size and so forth. So, uh, without Monash's help, um, we probably wouldn't be here without the funding from FIAL as well.

[00:10:19] ANNA: And one more point on that, Troy, one of the things Monash uncovered for you was the fermentability of Ninjin. Uh, fiber being really significant. Can you, can you explain to us what, what they found and why it's important?

[00:10:36] TROY: Yeah. So, um, we're obviously thinking they might have some health benefits and, uh, Professor Haratos. Uh, work with the Department of Gastroenterology there. Um, and, um, she developed a study, uh, where we actually had a look at the human, they've got a mechanical human gut there. Um, and we did a study looking at, um, you know, what actually happened in, in the, in the gut itself.

[00:10:58] TROY: And we found that, uh, [00:11:00] you know, the creation of short chain fatty acids by the soluble fiber. Uh, really gave us a, uh, an opportunity that we had a product similar in efficacy to, or efficacy or similar in capability is something like inulin, which was quite, uh, which was quite interesting, which was the control we used for the study.

[00:11:16] TROY: So, um, yeah, it was, was, was very good. Well devised by Monash. We were hoping that we'd get a low FUDMAP. Um, but, um, obviously with the short term fatty acid, um, um, make up, uh, we, we couldn't, there was probably a little bit too much gas there, but that was at obviously higher concentrations and looking at humans.

[00:11:36] TROY: We've actually found in pet food that's not an issue.

[00:11:39] ANNA: And just, uh, for our, our listeners, inulin is a prebiotic fiber with very, very high fermentability. And what, what it does is it provides an energy source to cells in the the colon of the animal where they make short chain fatty acids, and that goes and feeds all the colonocytes in the gut. So [00:12:00] it's really important for guts health.

[00:12:01] TROY: It's also high in vitamin A, obviously, because of the carotenoid content. Um, and it also, we've been able to show that there's some, um, physical effects on the, on the human body in terms of increasing satiety and aiding laxation.

[00:12:14] AMANDA: Okay. So just because it's like carrot waste doesn't mean that things like vitamin A aren't in there anymore. Is that right?

[00:12:22] TROY: That's right. One of the things we looked at was taking the beta car, OID out beta quarantine. Um, but we've actually kept it in there because obviously that's a, you know, a plus in terms of the vitamin A content, it's about 25% of your recommended daily intake is in the carrot fiber.

[00:12:36] ANNA: And as well as beta carotene, the Ninjin carrot fiber is rich in all sorts of other Polyphenol antioxidants, isn't it?

[00:12:45] TROY: Yeah, it is. Definitely. It's full of a, um, a myriad of antioxidants and, um, you know, it's something that we're, uh, you know, looking to commercialize quite

[00:12:52] ANNA: Yeah. And, uh, I'm sure I've seen the paper specifically looking at some of the benefits of these, we call them fiber [00:13:00] bound phenolics on all sorts of things, including gut health in both humans and cats and dogs.

[00:13:06] AMANDA: And, um, am I right in thinking that the beta carotene and some of those other nutrients that you're talking about are heat sensitive? So was that sort of a factor in the kind of drying that you were looking for?

[00:13:19] TROY: Yeah, so we really didn't want to have it in there for a long time to dry, so it's actually dried very, very quickly, um, and so therefore it's, um, it, it retains a lot of its nutrients and the temperature wasn't overly high as well. So it wasn't actually, um, blowing it apart, if you know what I mean,

[00:13:36] AMANDA: And you mentioned that you did the digestibility study, uh, for pet food, but also a human study. So is the Ninjin fiber used in some human foods as well?

[00:13:47] TROY: Uh, yeah, we launched last year with Swiss Bidens, um, a, uh, earth range, um, and, uh, they developed a product called Inner Beauty Cleanse, uh, which is all about, you know, um, providing the microbiome and the gut to, [00:14:00] uh, and through the digestive tract to, uh, to help with your inner health.

[00:14:04] AMANDA: I love it. Um, now you've also turned your attention to the waste from tomato processing. And as I mentioned in the introduction, you're Australia's largest tomato processor. Uh, so just how many tomatoes are you actually getting through?

[00:14:18] TROY: So we harvest around 220, 000 tons of tomato, um, and, uh, we have about, we actually are quite good at, um, uh, reworking our waste into products like tomato paste and so forth, but we have about a 5, 000 ton problem with, uh, tomato skin and seed.

[00:14:35] ANNA: Hey, Troy, where, where did, well, where does this, these 5, 000 tons actually go to, if you're not doing something with them, where, where did it go?

[00:14:45] TROY: At the moment, we have to pay for them to be taken away and they get taken as cattle feed, I assume, yeah, or pig feed, sorry.

[00:14:51] ANNA: and was it the same for the ninja?

[00:14:53] TROY: Ninja goes to pig food as well, yes. So, it costs us quite an amount, quite a, no, it's a six figure amount to dispose of our [00:15:00] waste.

[00:15:03] AMANDA: And so how did you identify the benefit of that tomato skin waste? Was it a case of you had the waste and it was a cost problem and you also, I'm imagining, had a sustainability goal and then you went, Hmm, what's the value in this waste? Is that kind of in simple terms, what happened?

[00:15:22] TROY: Yeah, we sort of worked out, you know, that obviously, you know, that the, uh, the skin contains some, uh, You know, really good, uh, antioxidants, lycopene being one of them, of course, uh, and then the seed is very rich in oil and protein, um, and what we initially thought we'd actually do is actually have a dried skin and seed, but our dryer, serendipitously, uh, actually the, in the dryer, the skin floats to the top and is dried and the, uh, and the seed comes to the bottom and, uh, we can actually collect all the seed.

[00:15:52] TROY: Uh, so we get natural separation, which is, uh, very exciting for us.

[00:15:56] AMANDA: Ah, okay. So have you released two products, one from the [00:16:00] tomato skin and one from the seed?

[00:16:02] TROY: Uh, we're working on the seed at the moment, so we're working on tomato seed oil, which is obviously a cosmetic opportunity for us, uh, which is a bit outside of, uh, food and beverage. But, um, we've also been able to, uh, the meal that's left over, um, on a dry white basis has about 32 percent protein. So, we're very interested in it from a, uh, from a protein point of view as a, uh, potential aqua feed, maybe, or animal

[00:16:23] ANNA: Yeah. It's very high. Yeah. And it will still retain presumably some of its bioactives as well. Maybe.

[00:16:30] TROY: Yes, that's right.

[00:16:31] AMANDA: Now you mentioned the antioxidant lycopene. So is it. Is it just good because it's an antioxidant or is there something special about lycopene?

[00:16:41] TROY: Well, I think lycopene out of most of the, um, the carotenoids, I guess, is probably one of the highest in terms of its, um, ability to, uh, you know, impact free radicals. Um, so therefore obviously preventing, uh, you know, some of those issues of damaging of your DNA and so forth.

[00:16:58] AMANDA: And were there [00:17:00] similar challenges, uh, converting that waste into something of value? Did you, you, you mentioned that you're using the same, uh, drying technique, I, I gather.

[00:17:11] TROY: We are very fortunate the same dryer works for both because obviously the, the skin and the seed, um, the moisture content is actually quite high. Uh, but we're actually lucky to get it down through the dryer to about 10 percent moisture, below 10 percent moisture for our, uh, For our seed, which means that we can harvest the seed and, uh, and get it processed.

[00:17:28] AMANDA: Okay. Now I know we're using, uh, the LycoFiber in, in our range and presumably you're providing that to some other pet food manufacturers, but is it also going into some human food ingredients?

[00:17:42] TROY: Unlike our, uh, carrot process. And unlike our carrot process, which is, uh, aseptic, uh, our, um, our tomato process, the capture of the skin and the seed is, uh, not aseptic. Uh, but we're actually looking this year to put in a, a kill step, uh, that'll enable us to sell it to, [00:18:00] uh, to human grade. There's a lot of interest around it for, in terms of extending paste, uh, but also in, in terms of the lovely color that it has.

[00:18:07] TROY: And our technical team are very excited that, uh, now that we've optimized the process of our dryer, that you actually got a really good red, red pigment, um, which we think will be great in, you know, processed foods and, uh, and sauces and the likes.

[00:18:20] AMANDA: And just for the lay people and me, exactly what does aseptic mean?

[00:18:25] TROY: Uh, so basically you want to make sure that it's actually heated well above, so pasteurization is usually 72 degrees. Um, so what you need to do is to have the temperature high enough to kill all the bad bugs, essentially. Um, or most of the bad bugs. We're not doing it under UHT temperature. UHT temperature is about 115, uh, degrees.

[00:18:43] TROY: Um, but our temperature is around 80 or 90 degrees that will actually make it a, uh, Um, a bug free product that won't make you sick.

[00:18:51] AMANDA: Okay, excellent. And, um, how well accepted have the products been, both the Ninjin Fibre and the Leica Fibre?

[00:18:58] TROY: We've done most of the work on [00:19:00] Ninjin Fiber, um, and we've actually had some really strong, uh, interest in pet food, um, strong interest in consumer food, particularly for burger makers that are actually replacing 10 percent of their protein with Ninjin Fiber. You can actually reduce the shrinkage of your burger patty, um, and have no difference in taste and texture, but have the benefit of actually, you know, saving some money.

[00:19:20] TROY: Um, so there's been interest in there. And then obviously we've had some interest with, uh, nutraceuticals. Uh, and in particular, uh, with one company around the laxation benefit.

[00:19:29] ANNA: hey, Troy, do, do dogs actually like the carrot fiber?

[00:19:34] TROY: Well, our palatability trial showed that a, uh, we had a sample size of 30, uh, and they all preferred, preferred, uh, uh, the product made with, uh, carrot fibre over the control.

[00:19:45] ANNA: there you have it, folks. Dogs do like carrots,

[00:19:49] AMANDA: Ha,

[00:19:49] TROY: do. My dog loves carrots. He always, when I'm making, uh, dinner and I always drop him a few carrots, he

[00:19:54] ANNA: mind you. And what about the tomato? Have you done anything in [00:20:00] palatability on the tomato?

[00:20:01] TROY: Now, that's our next step, Anna. We, um, we really want to do some work around that. Um, really mimic what we've actually already done. Um, and, uh, and look at that as well. Um, our, our tests, our sample size of one, or, you know, my boss's dog and my dog, they like it, but, um, you know, we need to do a further study.

[00:20:18] TROY: So, uh, but our priority was Ninjinfiber, um, and, uh, And then obviously lycophyber now is a, is a, is a great complement to it. And it's not the only fibres we're actually going to produce. We're going to produce beetroot fibre, apple fibre, uh, and so forth.

[00:20:33] ANNA: Fantastic.

[00:20:34] AMANDA: well, I was going to ask you about your product development, um, horizon. So I know you haven't sort of finished all of the work on that yet, but can you talk about what would be nutritionally really helpful in, for example, beetroot fiber?

[00:20:50] TROY: Oh, beetroot fibre, um, you know, has some really interesting properties in terms of, uh, lowering cholesterol potentially. Um, also its source of nitrate makes it, you know, for a [00:21:00] human, if you're exercising, uh, you're actually able to get more oxygen into your blood. So there's actually a sports nutrition benefit, or there could be an equine benefit for, uh, obviously for horse races, horse, horse, yeah, horses.

[00:21:12] AMANDA: And are your competitors, your Australian growing competitors, following suit or trying to follow suit?

[00:21:19] TROY: Uh, they can, but it's quite a capital investment. So our dryer was about six and a half million dollars. Um, so obviously you've got that, uh, that step. Um, there's also not a lot of juice concentrate that's made. Um, there's a little bit of carrot that's put into juices around Australia, but in terms of, um, having the pulp like we have it, um, we're pretty unique.

[00:21:39] TROY: Um, and obviously the volume of our, of our carrot as well, you know, we get the, the economies of scale.

[00:21:46] ANNA: That's great to hear. We've actually got Australian sourced ingredients that we can use in our pet products. And I have to say, I am a fan of both Ninjin and Blyco and my dog certainly loved the Ninjin.

[00:21:59] AMANDA: And [00:22:00] we love using them too, just quietly.

[00:22:02] AMANDA: So, Anna, that was super interesting listening to Troy, but in a nutshell, if you had to explain to people the really key difference between the Ninjin fibre and the Leica fibre, what would you say?

[00:22:13] ANNA: So, Amanda, the, the lyco fiber or the tomato fiber that's really rich in lycopene, which is the antioxidant, gives tomatoes, it's it's red color, but it's also very rich in insoluble fiber. And this is a key difference. So lyco fiber, over the insoluble fiber, uh, acts a little bit like a broom, whereas the Nin engine fiber.

[00:22:36] ANNA: Is also rich in antioxidants and also very rich in beta carotene, which is a form of vitamin A. Uh, but importantly, Ninjin fiber contains both insoluble fiber and soluble fermentable fiber. So Ninjin, unlike Leica fiber, has a prebiotic benefit and that's really the key difference between the two.[00:23:00]

[00:23:01] AMANDA: Excellent.


[00:23:04] AMANDA: Now Anna, today's food hack is very, what can I say, carrot and tomato inspired.

[00:23:10] ANNA: That's right. So, look, if you can't get any ninjin or lycophybe, it was lycophybe, wasn't it? What you can do is next time you have carrots for tea, and we have them a lot in my house, or tomatoes for that matter, just save a little bit before you chuck them in the pan, throw them together in the blender.

[00:23:28] ANNA: and put a little bit on your dog's dinner and hey presto there's your lycopene and your beta carotene with a good dose of fibrofronin.

[00:23:39] AMANDA: Excellent. Well, that's pretty easy to implement and I've really enjoyed listening to today's show. And if you have to, we would love it if you left a review for us on any of the podcast channels on which you're listening. And if you follow us on Instagram, Facebook, or YouTube, you can also ask us a question and we will endeavor to [00:24:00] find the answer from either Anna.

[00:24:02] AMANDA: or another expert. See you in the next episode of the Pet Nutrition Show.

Join us in future episodes of the Pet Nutrition Show as we dig deeper into topics like the ideal protein content for pets, the importance of gut health, and the role of pet food in waste management. Let's create a sustainable and healthy future for our pets and the environment.

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