Nanotechnology is one of those industry buzz words and, like all segments, protein is climbing on board. Just as we thought the market was peaking, new applications seem to be forging a novel path for an old macronutrient. Mark J Tallon, PhD, discusses the issues that may lead to the next fiscal resurgence

The US protein market today is worth in excess of $1.4 billion dollars, according to recent Nutrition Business Journal estimates.¹ Frost & Sullivan estimates this will exceed $9 billion by the end of 2007, with plant proteins taking an increasingly larger share — up to 70 per cent — of the pie.² The source of protein has been shown to exhibit different functional influences, from rate of digestion to amino-acid composition and differences in food and beverage application such as texture and emulsification properties.

For some time, the leading milk-based proteins have been whey, followed by casein. The greater bioavailability and amino-acid profile of whey have held it at the No. 1 spot regarding protein supplementation. However, of late its competitors, including plant proteins and isolated milk-protein bioactives, are leading the way in protein research and novelty. The following is an overview of the latest advancements within the protein markets.

Nanoencapsulation
Nanotechnology is often thought of as next-generation technology, although issues regarding its safety as a food delivery system are still in question.3 Technology moving toward that of the nano scale is now being applied via the utilisation of protein-based technology that could be used to encapsulate vitamins, minerals and enzymes.

Alpha-lactalbumin is protein extracted from milk and widely used as a food and dietary-supplement ingredient. The protein also has important nutritional values as a calcium ion binder and a rich source of the amino acid, L-tryptophan. The amino acid is mostly used in the animal-feed industry, but it also has a number of food applications, including clinical nutrition (infant formulas) and supplements designed for bodybuilders. Danish firm Arla Foods, the leading alpha-lactalbumin producer, has begun to exploit the unique abilities of this protein to form nanotubes (8.7nm pore size — about 10,000 times thinner than human hair). These nanotubes have the potential to be used in an encapsulation format (controlled delivery), and based on recent reports are stable during freeze drying and certain heating conditions (ie, pasteurisation), as well as clear when formed into a gel.4 Innovative techniques for food design are becoming important for food manufacturers; an alpha-lactalbumin-based nanotube is one such application.

Soy gets sporty
Over the years soy has played second fiddle to whey as a protein source, especially in the sports-supplement market. One of the main factors in the success of whey has been the belief that it houses a more complete amino-acid composition, which provides a more effective protein source for muscle building and recovery than soy. However, research published in 2007 may change this perception.5

The purpose of this investigation was to compare the early response of skeletal-muscle protein synthesis following supplementation with soy + carbohydrate (SC), whey + carbohydrate (WC), or carbohydrate only (CO) after endurance exercise. Rats were split into two groups, either nonexercised controls or treadmill-exercised for two hours, approximately 75 per cent VO2max. Following exercise, rats were then supplied with one of the three dietary interventions (SC, WC, CO).

One hour after exercise, serum insulin concentrations in WC, SC and CO were greater than in nonexercisers. Serum concentrations of branched-chain amino acids in WC and SC were higher than in CO, but amino acids making headlines in the sports-nutrition and weight-loss categories (leucine and isoleucine) were higher in WC than in the ES group. However, both WC and SC supplementation promoted the rate of skeletal-muscle protein synthesis and translation (mTOR; eIF4F) significantly more than CO, suggesting both soy and whey are effective for muscle-protein synthesis after endurance exercise. Well, at least in rats!

The protein high
No, not cannabis in the controlled-substance form, but hemp isolates are providing another useful protein source to give the industry a novel high. Hemp-seed extract provides some interesting nutritional qualities as it delivers a good source of essential fatty acids and an excellent dietary source of easily digestible, gluten-free protein. Its overall protein content of 34.6g/100g is comparable to that of soybeans, and better than other high-protein sources.6 Given the surge of nitric oxide-based products in the personal-care and sports-nutrition markets, the high content of nitric oxide-generating amino acids (arginine = 123mg/g protein and histidine = 27mg/g protein) may offer some additional marketing claims above that of other proteins.

In a recent study from China, researchers evaluated the compositional properties of this nonobvious protein source.7 Hemp (Cannabis sativa) protein isolate (HPI) was evaluated and compared with those of soy protein isolate (SPI). Edestin, a kind of hexameric legumin, was the major protein component. HPI had similar or higher levels of essential amino acids (except lysine), compared to those amino acids of SPI. The essential amino acids in HPI (except lysine and sulfur-containing amino acids) are sufficient for the FAO/WHO-suggested requirements for 2 to 5 year olds.

HPI contained higher free-sulfhydryl (SH) content than SPI, which affected some of its functional properties with regards to water holding. This will influence its application in some food groups. However, the data suggest that HPI can be used as a valuable source of nutrition for infants and children, but has poor functional properties compared to SPI.

The big message for those in the hemp industry trying to make this a fully functional food is to remove a large amount of the free-sulfhydryl groups that reduce its applications. Given its content and novelty, more work is warranted with regards to health and nutritional benefits that could be afforded from this novel protein isolate.

Tour-de-France babies
The infant-formulation market has become more targeted in its provision of bioactives, from fish oils to pre/probiotics. In a 2007 study, the next step in this fortification process may have arrived in the long-touted milk-protein fraction lactoferrin.8

Lactoferrin has an array of biological activities that include growth, immune-modulation and antimicrobial effects. 9^,10 However, over recent years it has struggled to keep its head above water due to, interestingly, an inability of companies to provide significant evidence to achieve acceptance for 'health claim status' and even 'acceptable for use in' from a selection of regulatory authorities across the globe. Although there is evidence that many of these issues could be resolved with the right package, it seems that only blunt science facts are going to kick the potential of this ingredient back on track.

The aim of this current study was to examine the impact of bovine lactoferrin supplementation in infant formula.⁸ Healthy, formula-fed infants (> or = 34 weeks gestation and

In a first, we have evidence of what I like to call the Tour-de-France effect where supplementation actually increases the oxygen-carrying capacity of these infants, and without the aid of altitude training. Following the 12 months of supplementation, hematocrit (ratio of red to white blood cells) levels were significantly higher at nine months in the lactoferrin-supplemented group compared with those on the control formula. These results provide some great insights into the benefits of lactoferrin fortification and, with the right industry backing, can raise the profile of this once holy grail of milk bioactives.

Protein still ISOLATE-d
As you can see, there is still innovation and growth possibilities within the protein market, but many companies are not capitalising on the possibilities. This lack of confidence in growth potential is leaving specific segments of the protein market ISOLATE-d and sales slowing. This has been especially evident in the RTD and MRP segment where the only innovations are coming from taste, and very few bioactives are on the market — Cysteine Peption from DMV being one such example.

The recent surge of new protein sources including wheat, rice, hemp, canola — each with its own unique bioactive profile — should turn this negative tide and open up the door for the next wave for the protein markets should the industry commit to the R&D path. Although whey seems to have bottomed out on price for direct-to-consumer sales, the raw-ingredient prices have still been on a slow increase. This has made for a difficult time for those with relatively low-volume sales to make significant margin benefits.

But as some suffer others flourish, and with human data on soy as being beneficial to resistance exercise in the pipeline, the sports-supplement market will finally have some beneficial information on an alternate protein source. Together these results signal the arrival of another avenue for the growth of the ever-topical protein market.

Mark J Tallon, PhD, is chief science officer of OxygeniX, a London-based consultancy firm specialising in claims substantiation, product development and technical writing.
www.oxygenix.com
Dr Tallon is also co-founder of Cr-Technologies, a raw-ingredients supplier.
www.cr-technologies.net
Respond: [email protected]

References
1. No Author. Sports Nutrition & Weight Loss Report 2006. Nutrition Business Journal. Penton Media, USA.
2. No Author. European Protein Ingredients Market. Market Report 2005. Frost & Sullivan, Texas, USA.
3. Lanone S, Boczkowski J. Biomedical applications and potential health risks of nanomaterials: molecular mechanisms. Curr Mol Med 2006;6(6):651-63.
4. Graveland-Bikker JF, et al. Structural and mechanical study of a self-assembling protein nanotube. Nano Lett 2006;6(4):616-21.
5. Anthony TG, et al. Feeding meals containing soy or whey protein after exercise stimulates protein synthesis and translation initiation in the skeletal muscle of male rats. J Nutr 2007;137(2):357-62.
6. Silversides FG, Lefrancois MR. The effect of feeding hemp seed meal to laying hens. Br Poult Sci 2005;46(2):231-5.
7. Tang CH, et al. Physicochemical and functional properties of hemp (Cannabis sativa L.) protein isolate. J Agric Food Chem 2006 15;54(23):8945-50.
8. King JC, et al. A double-blind, placebo-controlled, pilot study of bovine lactoferrin supplementation in bottle-fed infants. J Pediatr Gastroenterol Nutr 2007;44(2):245-51.
9. Ward PP, et al. Multifunctional roles of lactoferrin: a critical overview. Cell Mol Life Sci 2005;62(22):2540-8.
10. Gifford JL, et al. Lactoferricin: a lactoferrin-derived peptide with antimicrobial, antiviral, antitumor and immunological properties. Cell Mol Life Sci 2005;62(22):2588-98.