White Paper: : Its Significance in Sports and Geriatric Nutrition -

Unique plant-based are seeing high demand, with branched-chain amino acids receiving major marketing exposure

Introduction Protein is one of the most important macronutrients in our . The essential nutrient is a component of every cell in the body and is vital to its overall health (Pederson and Cederholm, 2014). Many different types of proteins exist in our body, making up important building blocks of bones, muscles, cartilage, skin, hair and blood. Excluding water, protein makes up 75% of body weight. All protein is composed of 20 amino acids. Depending on the protein type, these amino acids are held together at the molecular level by different bonds. Of the 20 amino acids, only 10 are considered "essential" to obtain from the diet (, , , , , , , , and ), as these cannot be synthesized by the body, and are very important, as the body utilizes these amino acids to manufacture the other 10 "non-essential" amino acids. It is important to note that while arginine is not an essential , as it can be manufactured in the body of adults from other amino acids, supplementing the body with higher levels of this amino acid can produce muscle-preserving effects and increase blood flow, as a nitric oxide precursor, as described later. Regardless of its source, all proteins, either from animal or plant, are composed of the same amino acids, but the ratio of these amino acids is typically quite different.

Most plant proteins, unlike animal- and dairy-derived proteins, are not generally considered "complete" proteins, as these may lack adequate levels of one or more of the essential amino acids, such as methionine, tryptophan or lysine. Soy protein is an exception, because it has all necessary essential amino acids to be considered complete. The amino acids lacking in certain plant proteins, or "limiting" amino acids, differ by plant protein source. In order to use plant proteins as "complete protein systems", other than soy protein, the protein industry typically selects different plant proteins to equalize the amino acid profiles of plant- protein products with those from animal origin. A popular combination is pea protein blended with brown or oat protein(s). For example, brown rice protein is high in methionine and tryptophan but typically lacks adequate lysine levels to be classified as a complete protein source by itself, while pea protein is the other way around. As a consequence of certain limiting amino acids, vegetarians and vegans need to consume a variety of plant protein sources in their diet or a unique blend of plant proteins, such as those in ProNexTM plant protein blend (see below for more information), to meet their complete protein requirements.

Protein and Human Health Protein is a very important dietary component, influencing the metabolism in many aspects of human health ((Elmadfa and Meyer, 2017; Pederson and Cederholm, 2014; Wu, 2016). Our body breaks down dietary protein into its individual amino acids that it then uses to maintain proper day-to-day bodily functions, provide growth and repair tissues. For example, protein is used to create enzymes that are required to perform specific chemical reactions in the body, like helping to break down food components, such as carbohydrates, fats and proteins so they may be used by the body. Protein is also used to make antibodies for disease resistance, hormones that are used as metabolic signaling agents to coordinate various bodily functions, and collagen, a structural component of skin, bones and tendons. Proteins also help facilitate transport and storage of various hormones, medicines and enzymes throughout the body. Science has proven that these functions increase lean body mass, maintain current muscle tissue size and help strengthen bones. Protein also does not induce fat storage and it aids glycemic control. Because of these attributes, protein is an effective component in weight loss plans, helping to normalize blood sugar and induce satiety (suppresses hunger), while providing necessary amino acids that act as building blocks that promote muscle recovery following exercise; an important consideration for athletes and exercise enthusiasts.

However, unlike the body's ability to store fats and carbohydrates, the human body does not possess the ability to store protein; it has no reservoir to draw at times of need. So, it is important to consume enough dietary protein daily, but the sufficient quantity depends largely on age, gender, health, and on the level of physical activity. Typically, the majority of people in Western society get adequate protein levels in their diet, but in certain cases, such as those that partake in intense physical activity (athletes) and aging adults (geriatrics), higher protein intake is necessary.

Protein intake recommendations for normal healthy adults, training athletes and aging adults The Daily Reference Intake (DRI) value of protein for healthy adults as established by the U.S. Institute of Medicine (IOM) is 0.8 g of protein/kg of body weight (0.36 g/lb) per day (IOM, 2005). However, a recent 2016 joint position paper on nutrition and athletic performance, the American College of Sports Medicine (ACSM), the Academy of Nutrition and Dietetics (AND), and Dietitians of Canada recommended that higher protein intakes are necessary for athletes, and athletes should also consider the timing of the protein intake (Thomas et al., 2016). The joint paper on nutrition and athletic performance made no distinction between strength and endurance athletes, citing that dietary protein intake necessary to support metabolic adaptation, repair, remodeling, and for protein turnover typically ranges from 1.2 to 2.0 g/kg (0.5 to 0.9 g/lb) of body weight per day. Furthermore, they recommend that daily protein needs should be met using an intake plan that spreads the total daily amount of high-quality protein across the day and following strenuous training sessions. The joint commission also noted that muscle protein synthesis is maximized by consuming 0.3 g protein/kg body weight every three to five hours, including consuming this amount within two hours post-exercise. A more recent systematic review, meta-analysis and meta-regression performed in 2018 on the effect of protein

supplementation on resistance training-induced gains in muscle mass and strength in healthy adults found that consuming 1.6 g/kg (0.73 g protein/ lb) of body weight per day was the most effective dose for building muscle, and also determined that timing of protein intake was not important for gains in muscle mass and strength (Morton et al., 2018). The study published in the British Journal of Sports Medicine determined that as long as daily protein intake of 1.6 g/kg body weight per day was separated into 0.25 g/kg body weight doses, the total amount was sufficient for muscle protein synthesis.

In addition to specific recommendations for performance athletes, current studies from the PROT-AGE Study Group (2013) also suggest that most individuals over age 65 should consume about 1 g to 1.2 g of protein/kg of body weight (0.45 to 0.55 g/lb) per day to both gain and maintain muscle mass and function (Bauer et al., 2013), as age-related muscle loss, known as sarcopenia, ranges from 0.5% to 2% of total muscle mass each year after the age 50 (Buford et al., 2010; Mitchell et al., 2012; Nair, 2005). Studies have suggested that starting in our late 20s and early 30s, individuals begin to lose muscle mass, with physically inactive people losing as much as 3% to 5% per decade after age 30 (McLeod et al., 2016; Mitchell et al., 2012; Sinnige et al., 2013). The rate of sarcopenia typically takes a significant increase around age 75, but may also increase as early as 65 or as late as 80, becoming a major factor in frailty and increased potential for falls and fractures in older adults (Santilli et al., 2014; Shafiee et al., 2017; Walston, 2012).

There is currently no separate recommendations for people between the ages 50 and 65, but it is safe to say that getting enough protein during that time is sound nutrition sense (Nowson and O'Connell, 2015), as by age 65, both exercise and high-quality protein intake are necessary , as older adults are less efficient in using amino acids from protein for muscle protein synthesis than are young adults, a phenomenon known as "anabolic resistance" (Cuthbertson et al., 2005; Drummond et al., 2008; Chul Jang, 2016; Shad et al., 2016). The definition of what constitutes high-quality protein will be defined under the assessments and branch-chain amino acid sections). Studies clearly show that equal amounts of protein do not stimulate muscle protein synthesis (growth) the same in older versus younger adults (Drummond et al., 2008; Cuthbertson et al., 2005). Older adults require much more muscle stimulation than their young counterparts to initiate muscle growth, an effect that may be related to reduced blood flow to muscle tissue (Burd et al., 2013). Older adults have also been shown to experience decreased appetite with aging (Malafarina et al., 2013; Pilgrim, 2015), possibly from denture use or chewing difficulties (Lee et al., 2006), constipation issues (Soldmdal et al., 2012), or use of certain medications that reduce appetite or alter sense of taste or smell (Qato et al., 2008; Schiffman, 1997), thus making it more difficult to maintain proper caloric and protein intake. In a recent study performed in 2015 by Kim and colleagues at the Center for Translational Research in Aging and Longevity at Little Rock, AK, adults over the age of 50 who approximately doubled the DRI of protein, consuming 1.5 g/kg (0.68 g/lb) body weight, were better able to rebuild and retain muscle after only four days, when compared with a healthy control group consuming only the DRI recommended level of 0.8 g/kg body weight. But, increasing protein above the DRI level can help decrease or slow the loss of age-

related muscle mass, especially when combined with resistance training, as higher protein intake alone does not typically build muscle, rather muscle building and muscle strength are the result of exercise. So, in addition to consuming adequate protein levels for the level of physical activity and condition, exercise is equally important to help maintain muscle mass, strength and coordination, key elements in health, particularly in aging adults, as loss of age-related muscle mass (sarcopenia) and age-related loss of muscle strength (dynapenia) are major factors in balance, and long-term mobility in older adults (Clarke and Manini, 2010; Lauretani et al., 2003; Seene and Kaasik, 2012; Walston, 2012).

Dr. Lauri Wright, an assistant professor of nutrition at the University of South Florida and spokesperson for the Academy of Nutrition and Dietetics, points out that the average senior is only consuming 16% of daily calories as protein, as compared with current recommendations of 10% to 35% of daily calories for optimal health. Following data from the 2015 Kim aging and longevity study, Wright further recommends that older adults practicing fitness using regular resistance training increase their protein intake to 1.5 g/kg of body weight per day. Although, it is important not to exceed 5.0 g/kg (2.3 g of protein/lb) of body weight per day or get more than 35% of daily calories from protein, as very high doses places excessive stress on liver processing, and may cause excessive blood ammonia levels, nausea, diarrhea and even potential mortality (Bilsborough and Mann, 2006). Higher protein intakes, of up to 35% of daily calories, also pose a risk to older people that already suffer from some type of kidney function impairment (Paddon-Jones et al., 2008).

The bright spot in the debate of protein intake for adults over 50 is that higher protein intake can significantly protect muscle and strength, even during weight loss, with the combination of resistance training and higher protein intakes, with the key being to provide the body with plenty of high-quality protein to buffering the aging process (Heaney and Layman, 2008).

Market demand for proteins Due to growing concerns about world obesity and diabetes, and the increasing desire for vitality, demand for protein, because of its influence on appetite suppression, muscle building and glycemic control, has grown significantly worldwide, particularly as a dietary aid to help athletes in recovery and senior adults prevent muscle loss. According to a recent report from Research and Markets, the global whey protein market was valued at $9.4 billion U.S. in 2017, although the value of the plant protein market was slightly above this at $10.5 billion U.S. It is important to note that the bulk of whey protein ends up in the sports nutrition sector, while the use of plant proteins spans virtually the entirety of packaged foods. By 2025 it is estimated that the market for plant proteins will grow to $16.3 billion U.S. and by 2054, one-third of all protein sources will be plant-based (Statista, 2019).

Many excellent protein sources are available from either animals [e.g. whey, casein, yogurt (particularly Greek-style), egg, beef, and fish] or plant [e.g. soy, rice, pea, ], differing in numerous ways, such as the presence of allergens from egg, dairy and soy, potential anti-nutrients (phytates, protease inhibitors, lectins

and saponins), cholesterol, saturated fats, digestion rate, or the relative amount of individual amino acids. Of these, whey protein has been the "gold standard" for use in performance protein supplemental systems due to its complete amino acid profile and relatively high rate of amino acid absorption. According to a recent meta-analysis of 14 randomized controlled trials (RCTs) involving 626 adults published in 2014 in the Journal of the American College of Nutrition, whey supplements significantly improved participants body composition in multiple studies, especially when combined with resistance training (Miller et al., 2014). A more recent study published in 2017 in the research journal, Nutrients, investigators determined that whey supplements also enhanced whole body protein metabolism and improved performance recovery after resistance exercise (West et al., 2017). However, due to its lactose content, animal derivation and increasing cost, plant-derived protein sources are now realizing higher demand as highly effective alternatives, particularly for vegan and gluten-free foods. The interplay of multiple trends in protein demand have led to this surge in vegan-type plant protein sources.

Consumers have inclined to divert from animal and dairy-based proteins to several unique plant-based proteins due to their easy digestibility, sustainable production, relatively inexpensive price, as well as health and ethical reasons. Research has also shown that plant-based proteins are also significantly better for the environment than animal protein, such as beef, producing 10-fold less greenhouse gas emissions than similar beef-based products (FASEB, 2016). The primary point is, plant proteins are not just for vegans and vegetarians , with the primary market strategy being, not to exclude anyone. Vegan protein sources have a large advantage as having the widest possible acceptability in today's market environment, with possible exception to allergies, which is why diversity in protein sources within a final powdered protein product blend is important. Also important, are any protein sources that are genetically engineered or destroy the rain forest, which makes many reject soy protein.

Recently, recognizing that the regular intake of plant-based foods, such as vegetables, fruit, whole grains, and plant-based proteins are lacking in most Canadian diets, Health Canada (Global News, 2019), following recommendations of their sponsored consultation report by Earnscliffe Strategy Group (2018), has drafted a new Canada Food Guide that focuses on encouraging Canadians to consume more plant-based proteins (HC, 2019). This focus towards a high proportion of plant-based foods is designed to help Canadians consume more fibre-rich foods, eat less red meat, and replace foods that contain mostly saturated fat with foods that contain mostly unsaturated fat.

In effect, the growing trend behind Health Canada's new emphasis, and the element fueling the global demand for vegan proteins is flexitarianism, a movement where people are not fully vegan or vegetarian, but rather are "semi-vegetarian" and only wish to reduce animal-derived foods in their diet (Derbyshire, 2016). In addition to flexitarian diets, the high protein trend in the market is also raising the popularity of high protein consumption, which is an important aspect of driving sports nutrition products in the mainstream.

As mentioned, the drive for high protein is being fueled by increased consumer understanding of protein's value as a dietary component that can help build muscle, strength, endurance and performance, recover from exercise, provide a vehicle for weight management and promote glycemic control in diabetes, regardless of gender.

As mentioned, whey protein (concentrates and isolates) have been the "gold standard" and most demanded protein source for addition into foods and beverages, as it is a complete protein source, meaning it contains all 9 (given adults do not need arginine) essential amino acids, while a primary concern of using plant proteins is that many are typically limited in one or two of these amino acids, such as lysine, methionine, and/or . However, proteins derived from milk (such as whey and casein), soy, wheat and eggs are known to induce allergies in predisposed individuals. About 65% of the entire human population and about 90% of East Asians are also lactose intolerant (NIH, 2019). Whey protein concentrate, for example, contains up to 5% lactose, causing untoward effect in disposed individuals. Individuals with lactose intolerance may experience gastric discomfort at high whey protein concentrate intake, an issue that can be eliminated by consuming a whey protein isolate with higher protein, lower lactose levels, or a non-dairy-based protein source.

Soy protein, one of few plant protein exceptions as a complete plant protein source, has dominated market share in the plant protein category, even though, like the dairy, wheat and eggs mentioned above, is considered among the 8 most allergenic foods. Soy also has poor reputation in terms of sustainability (including being associated as a genetically-modified crop that is destroying the rainforests), has digestive issues, and, as some early research has reported, may impair men's hormonal balance. Furthermore, recent studies have also determined that compared with whey, soy protein, due primarily to its inferior digestibility, does not stimulate muscle growth as effectively as whey, milk or egg (van Vliet et al., 2015; Volek et al., 2013), suggesting that blending various plant protein sources can create complete amino acid profiles and help improve skeletal muscle anabolic response. Soy is also a rich source of phytoestrogens, compounds that have similar molecular structure as the hormone estrogen. A few studies have indicated that high soy intake may cause decreases in the male hormone testosterone, with corresponding increases in body fat and the expense of muscle mass. Although, there are many studies that refute these earlier studies, some athletes, particularly body builders, remain concerned about using soy or soy protein products.

Due to the concerns about soy, and desires to consume more vegan-type proteins, new plant-derived proteins, such as those from rice and pea, due to their hypo-allergenicity, lack of gluten and a healthy nutritional profile have begun to attract significant market demand. In the U.S., soy protein use has begun to give way to pea protein and other plant protein sources. Recent 2018 data from Lumina Intelligence, a global consumer product and trends analytical group, show that 22% of protein powders in the U.S. are plant-

based and that pea protein is contained within 80% of those powders, as compared with only 12% that use soy protein (Lumina Intelligence, 2019).

Yellow pea, a legume, has protein that contains legumin, a highly effective long-chain protein that is referred by some as "vegetable casein" as it is analogous to casein contained within dairy products. Legumin, like casein, being a long-chain protein source, takes longer to digest than whey protein, thereby providing a longer, more effective anti-catabolic (muscle-preserving) effect for body builders needing to recover from muscle damage following intense weight training (Babault et al., 2014; Engelen et al., 2012; Jäger et al., 2017). This effect is also important for senior adults to reduce age-related muscle loss. Pea protein is also a rich source of glutamine, arginine, and lysine. In fact, it contains about 3-times the level of arginine as whey protein, an amino acid important as an ergogenic agent in sports nutrition (Campbell et al., 2004). L-arginine contributes to muscle growth as a key signaling agent in skeletal muscle cells, encouraging release of growth hormone and fat break down, while serving as a precursor for vasodilation through nitric oxide production, increasing blood flow to promote endurance and muscle conditioning. Although pea protein is not classified as a complete protein in itself, it lacks adequate levels of methionine and cysteine, it contains high levels of branched chain amino acids, and, as mentioned, arginine for muscle development (refer to ProNexTM Pea Protein white paper). A recent 2015 study has shown that when combined with resistance training, individuals using pea protein produced the same amount of muscle mass as individuals using whey protein (Babault et al., 2015).

Like pea protein, brown rice protein is also not classified as a complete protein, as it lacks adequate lysine, however, it also contains relatively high branch-chain amino acid levels for muscle development (refer to ProNexTM Brown Rice Protein white paper). Consumption of brown rice protein following resistance exercise has also been evaluated against whey protein for its effects on muscle metabolism in a recent Nutrition Journal study (Joy et al., 2013). The study found in 24 college-aged, resistance-trained males that consumed either 48 g of rice or whey protein isolate post-exercise for 8 weeks, that rice protein decreased fat and grew lean body muscle mass, while increasing power and strength equally well as whey protein, if provided in high isocaloric doses. The author's data suggest that differences in protein consumption are of less relevance when protein is consumed in high doses throughout periodized (resistance training). By blending high quality whole pea and whole brown rice proteins together, the limiting amino acids in each individual protein can be eliminated, resulting in a complete protein source, containing high branched chain amino acids and high arginine levels for proper human nutritional support and positive benefits on muscle growth and muscle sparing.

Digestibility is an important aspect of protein utilization and performance. As pea and rice protein are both highly digestible and provide exceptional muscle-building potential, high-quality sourced combinations of the two plant proteins can result in a superior amino acid profile comparable to dairy-based whey protein (Table

2), while avoiding potential allergenic reactions or digestive issues of certain animal-based or soy protein sources, resulting in high consumer demand.

The question now becomes, what constitutes high quality protein, as it pertains to muscle recovery and maintenance for athletes and senior adults.

Protein Quality Assessments In order to be classified as a good alternative to animal or dairy-based protein, for a plant protein to be used as a substitute for human consumption, it must meet certain quality parameters. The protein source must have a high total protein content, but equally important is its digestibility, a factor necessary to elicit amino acids for use by the body. Proteins can be easily digested, such as whey protein, or slowly digested, such as casein or pea protein, with rice protein falling somewhere between whey and pea protein. As mentioned, soy protein is not well digested. The digestion rate determines how quickly their amino acids will be available for use post-exercise for recovery and metabolic effects. Protein should also provide a proper quantity of 9 essential amino acids (EAAs), have high branched-chain amino acid (BCAA) levels with relatively high leucine (a BCAA) content and a ratio of these BCAAs (leucine: isoleucine:valine) from at least 1:1:1 to 2:1:1, or higher leucine.

Proteins have different amino acid compositions, digestibility, and, as a result, bioavailability, which can influence their quality. Various protein quality assessments are used to assess these quality attributes (FAO/WHO, 1990). Several different protein rating scales are known to determine quality, including, but not limited to: the protein efficiency ratio (PER), biological value (BV), net protein utilization (NPU), and the most commonly used ratings system, the Protein Digestibility Corrected Amino Acid Score (PDCAAS), which was recommended by the FAO and became the industry standard in 1993. However, FAO has recently recommended a replacement to the PDCAAS, the Digestible Indispensable Amino Acid Score (DIAAS), a superior, more preferable method than PDCAAS, as PDCASS does not account for anti-nutrient factors such as phytic acid and trypsin inhibitors (FAO, 2013). The less often used methods, BV, PER, and NPU, do not provide much information about the amino acid profile, and have certain limitations, as they provide either indirect measures of utilization by the body, as in BV and NPU methods, or do not correlated with human growth needs (PER). Table 1 shows PDCAAS and some DIAAS values as measures of protein quality of some animal and dairy proteins and several plant-derived proteins.

As Table 1 shows, most individual plant-based proteins do not provide a complete profile (defined as the PDCAAS or the DIASS). However, plant protein sources that are incomplete, such as traditional brown rice protein and yellow pea protein, may be effectively utilized to create complete plant protein systems through blending, thus creating a highly effective alternative to animal-derived protein, while eliminating the unwanted issues identified by vegan and vegetarian consumers. For example, traditional brown rice protein is high in the sulphur-containing amino acids, cysteine and methionine, but

low in lysine. While pea protein is rich in lysine but low in the two sulfur-containing amino acids. Combining them together in proper ratios completes the protein requirements, providing a unique blend of amino acids with exceptional properties.

Table 1. Typical Protein Quality Comparative Values for Animal and Plant Sources

Protein type PDCAAS DIAAS Whey (conc) 1.00 1.15 Egg 1.00 NA Casein 1.00 1.11 Milk 1.00 NA Soy concentrate 1.00 0.92 ProNexTM COMPLETE 0.95 NA Rice protein (whole brown) 0.60 0.45 Pea protein (whole yellow) 0.66 0.44 Wheat (gluten) 0.25 0.40 Adapted from: FAO (2013), Rutherford et al., 2015, U.S. Dairy Export Council 2008, Mathai et al., 2017, Sarwar, 1997; Nexxus specs.

Significance of branched-chain amino acids (BCAAs) and their ratio

Along with the need to consume complete well digested proteins, is the desire to consume protein sources that have relatively high branch-chain amino acid (BCAA) levels, which include the amino acids leucine, isoleucine and valine, as these amino acids make up more than one-third of muscle protein (Blomstrand et al., 2006; Kimball and Jefferson, 2006; Kraemer et al., 2006). BCAAs play a special role in muscles as, unlike other amino acids that are metabolized in the liver, they can be metabolized within muscles (Cole, 2015). These essential amino acids are highly important in health and disease (Holeček, 2018), having influence in signaling functions (Kerksick et al., 2008), specifically through activation of the mTOR signaling pathway, resulting in positive effects on a wide variety of metabolic and synthetic functions, including increased protein translation, improved insulin resistance, increased insulin-independent glucose transport, fat loss, and reduced oxidative stress following severe injury and infection (La Bounty et al., 2008; Mattick et al., 2013; Nishimura et al., 2010). So, BCAAs are essential in promoting protein metabolism, promoting muscle growth and recovery (Blomstrand et al., 2006; Norton and Layman, 2006; Shimomura et al., 2006), neural function (Blomstrand, 2006; Newsholme, 2006; Davis, 2006), and regulating both glucose and insulin (Brosnan and Brosnan, 2006). Moreover, it has been determined that the BCAAs, particularly leucine, stimulates skeletal muscle protein synthesis (Garlick, 2005; Volek et al., 2013). Because of significant involvement in aspects of muscle recovery and mass increases, BCAAs, particularly leucine, are viewed by many as even more important than many of the other essential amino acids for sports nutrition (Lumina Intelligence, 2018).

Generally, animal-based protein sources, such as beef, lamb, pork, poultry, fish, eggs, milk and milk products, typically contain higher amounts of the BCAA leucine (approximately 8-11% ), while plant-based proteins generally contain lower levels, about 6-8% leucine (Kalman, 2014). BCAAs from dairy sources, may see levels up to 20% of the total amino acid profile, but are typically about 16% of the total amino acid profile (Gorissen et al., 2018). Certain plant proteins, such as brown rice and pea proteins are also excellent sources of BCAAs, and may comprise levels up to about 17% - 19% of their total amino acids as BCAAs (Kalman, 2014; USDA, Item 20036, 2018), although more typically these levels are 10-11% (Gorissen et al., 2018). The BCAA levels, and other protein quality parameters, depend on the protein source and method of manufacture. For example, whey protein and certain brown rice protein sources, such as sprout brown rice protein (SBRP), have been found to have near equal amino acid absorption (98.8% correlation). The branched-chain amino acid leucine from brown rice protein has also been shown to be more readily absorbed than that from whey (Joy et al., 2013).

As mentioned previously, plant proteins also boast other amino acids that are at higher levels than whey, such as pea protein that contains more than 3-times more arginine than whey (Gorissen et al., 2018), an amino acid that is important to athletic endurance. In addition to their BCAA levels, different protein sources may have different BCAA ratios.

BCAA ratios, for better or worse, have become a primary marketing tool in the sports nutrition protein category, with ratios often forming part of a protein product's name or at least part of its overall branding. Determining the so called, "optimum ratio" has also been investigated in certain medical research studies, such as in intestinal cell proliferation and protein metabolism (Duan et al., 2018) and in parenteral nutrition (Iwasawa et al., 1991), which cited that the most optimal ratio was 1:0.5:0.25 and between 1:1:1 and 2:1:1, respectively. The best BCAA ratio to use continues to be debated for its relevance in sports nutrition and clinical medicine, and no clear evidence is currently available that yields scientific consensus on the subject, but, if the number of protein products containing a specific BCAA ratio is any guide, the BCAA ratio of 2:1:1 (leucine:isoleucine:valine) is the most common. This is the same ratio found in muscle tissue, and although other ratios are also used in supplemental protein power blends, almost all variations alter the proportions of leucine to isoleucine and valine, such as 4:1:1, 6:1:1, 8:1:1 and 10:1:1. Given that an argument can be made from research study, based on a BCAA ratio of 2:1:1 for maximizing: pre- and post workout muscle protein synthesis (Koopman et al., 2005; La Bounty et al., 2008); energy and fighting fatigue (Blomstrand, 2006; Gomez-Merino et al., 2001); fat loss though PPAR activation and food intake through hypothalamic mTOR signaling (Nishimura et al., 2010; Cota, 2006), a ratio of 2:1:1 (leucine:isoleucine:valine) may be the ratio to use for sports nutrition protein powder products (Stoppani et al., 2018).

ProNexTM COMPLETE is a highly effective alternative to animal and dairy protein sources Whole brown rice and pea proteins, which provide amino acids from each layer of their kernels have excellent digestibility and provide exceptional muscle-building attributes, equal to whey protein, as defined in recent research studies. By selecting premium sources of the two plant proteins, a unique blend has been created that provides a superior amino acid profile that has essential and branched-chain amino acids that are comparable to whey protein isolate and has a 97% correlation with the standard requirements imposed by the 2007 Joint WHO/FAO/UNU report in human breast milk (Zhang et al., 2013). The premium blend provides exceptional nutritional support for infants and a highly effective amino acid profile for performance athletes and geriatrics, containing all the essential amino acids as a complete protein, including high levels of BCAAs, particularly leucine, with a BCAA ratio of 2:1:1 (leucine:isoleucine:valine). Being highly digestible, gluten- free, hypoallergenic, and not generating ethical issues with its use, ProNexTM unique whole pea and whole brown rice protein blend provides an excellent alternative to animal and dairy-based protein systems, such as egg, casein and whey.

With its well-known expertise in the industry, Nexxus Foods has created a customized alternative to whey, while reducing the potential for allergic reactions. In addition, their ProNexTM COMPLETE produces a branched chain amino acid profile that is similar to whey protein, Table 2, with a BCAA ratio that is more typical of that found in muscle tissue. The unique blend also has an arginine content that is 3-times that of whey protein isolate. Blending various plant protein sources allows Nexxus Foods to create high quality animal-protein alternatives that have comparable amino acid profiles, without allergen or ethical concern.

Table 2. Comparison Between ProNexTM COMPLETE and Whey Protein Isolate

Nexxus ProNexTM Whey Protein* COMPLETE** Total protein content (g/100g) ≥ 80 ≥ 80 Essential amino acids, ΣEAAs (g/100g)/% total AA 47 40 Branched-chain amino acids, ΣBCAAs (g/100g)/% total AA 22 19 Branched -chain amino acid ratio (Leu:Isoleu:Val) 2:1:1 2:1:1 Leucine (g/100g) 10 7 Arginine (g/100g) 2 6 PDCASS 1.00 0.95 From: *US Dairy Export Council 2008; **Nexxus 2019 technical data.

ProNexTM COMPLETE is a highly functional food ingredient with many applications Protein is an essential part of our diet, as it is the primary means for the human body to maintain lean body mass. Apart from its necessary nutrition value, various proteins play important roles in adding technological value to food systems, such as helping improve texture, consistency and mouth feel, product yield, and overall quality to processed foods. These technological functions are primarily related to the molecular structure of a specific protein, and how the protein is processed.

Plant proteins such as brown rice protein and pea protein are widely used in many processed foods, infant foods and sports nutrition applications due to its protein content, low fat levels, amino acid profile, hypo- allergenicity, gluten-free property, relatively neutral taste, ease of digestion, and its dispersion and stability in liquid systems.

For example:

• In sports nutritional products, meal replacement systems and weight management products, such as protein beverages and mixes, bars and smoothie systems, ProNexTM COMPLETE disperses and adds suspension to mix product systems and provides excellent nutrition, particularly in blended protein systems, with neutral taste and aroma; • In infant formulas, ProNexTM COMPLETE is hypoallergenic, has a 97% correlation to the standard requirements for essential amino acids in human breast milk (WHO/FAO/UNU, 2007; Zhang et al., 2013), and has excellent powder formula mixing, producing a smooth, creamy formula; • In bakery systems, ProNexTM COMPLETE provides a hypoallergenic ingredient for vegan and vegetarian and gluten-free foods with a well-balanced amino acid profile, as well as providing longer shelf life and enhanced dough rheology, with excellent flour mixing capacity; • In dairy-free food systems, such as yogurts, ice cream, whipped toppings and cheeses, ProNexTM COMPLETE can provide hypoallergenicity and texture equal to dairy-based protein systems; • In hair care systems, ProNexTM COMPLETE helps strengthen and expand hair diameter to create thicker, more voluminous looking hair.

Depending on the plant protein source and its method of manufacture, some plant proteins, such as soy proteins, have been known to carry some musty, earthy and/or slightly bitter off-flavor notes. Unlike many soy and legume flours and proteins, ProNexTM unique plant protein combination typically has a neutral flavor profile. However, if you are using other proteins and flour systems and have flavor issues, Nexxus Foods provides custom solutions to meet your needs.

References

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