Creating Convenience Food Based on Human Nutritional Requirements

by Dr. Anthony Robson

Diet induced disease is epidemic. Worldwide because the changing food system has ignored the nutrient requirements of people. High energy density and low nutrient density which characterise the modern diet must be overcome simultaneously. Overweight and obese people can develop paradoxical nutritional deficiency from eating high energy dense foods with a poor nutrient content¹.

The finding that people with a low energy dense diet (<1.6 kcal g^-1) have the lowest total intakes of energy, even though they consume the greatest amount of food has important implications for promoting compliance with a healthy diet². A convenience food which is not both low energy dense and high nutrient dense dilutes the diet of the low energy dense foods of high nutrient density that humans should eat: the most nutritious cooked wild plant and animal foods for humans^{1, 3-6}.

Our ancestral exemplar is the late Palaeolithic diet i.e. a wild plant-to-animal energy intake ratio ~1:1, with fish and shellfish providing a significant proportion of the animal component⁷. However, many foods consumers may consider natural are not due to agriculture, animal husbandry and food processing. Furthermore, the focus on just reducing dietary fat^8,9 must be refocused on reducing the positive imbalance between the intake and the expenditure of food energy.

Low fat, high carbohydrate cereal based products are often of high energy density. For example a Masterfoods Twix® chocolate biscuit bar: 56% carbohydrate and 2.2% water = 5.5 kcal g^-1, Kellogg's Special K®: 71% carbohydrate and 3% water = 3.8 kcal g^-1, white bread: 51% carbohydrate and 36% water = 2.7 kcal g^-1, while roasted wild water buffalo meat: 0% carbohydrate and 69% water = 1.3 kcal g^-1, shrimp meat cooked in moist heat: 0% carbohydrate and 77% water = 1.0 kcal g^-1 and boiled celery: 4% carbohydrate and 94% water = 0.2 kcal g^-1 (c.f. Table I).

Table 1. Energy density and nutrient density of a selection of foods (value per gram)

Molecular recognition is biology's building strategy and key to nanotechnology: biomolecules e.g. self-assembled, water-filled, edible nanocells and nanotubes that self-organise into more complex structures¹³. Using molecular recognition convenience foods can be created in a more natural, low energy dense way i.e. with high water content¹³.

For example, molecular recognition can be used to structure a chocolate biscuit bar (solid convenience food) similar to a celery stalk, to increase its water and fiber content which will substantially lower its energy density (<1.6 kcal g^-1). This would allow the same amount of food to feed more people, increasing food security. Celery stalk cells are pressurised with water causing the entire plant to become turgid and stiff.

Food technologists can harness this natural turgor force to produce a firm chocolate bar, biscuit or breakfast cereal with a good bite while looking and tasting the same as before, to aid public acceptance¹³. Water carries flavour with few calories e.g. a cup of tea without milk = 0.01 kcal g^-1 and taste sensation per mouthful can be improved using the principles of Ultrafine food technology (Eminate Limited, Nottingham, UK); processing food on the nanoscale to increase the surface area that is in contact with taste and smell receptors.

The bioavailable nutrient content including cofactors of convenience foods must mimic and improve on the nutritional value of the most nutritious cooked wild foods for humans and can be increased using existing bioactive nanoencapsulation¹³. Algal biotechnology can provide the food industry with sufficient amounts of all the nutrients needed for mass scale optimal human nutrition including protein, DHA, EPA, AA, vitamins, minerals and fiber^14,15. Reducing particle size using nanotechnology can further improve the properties of bioactive compounds (e.g. DHA and EPA), such as delivery, solubility, prolonged residence time in the gastrointestinal tract and efficient absorption through cells¹⁶.

It is important to consider not only the energy content of the modern diet but also the energetic cost of its assimilation. A reduction in liquid calorie intake has been found to have a stronger effect than a reduction in solid calorie intake on weight loss¹⁷. Sugar sweetened beverages (SSBs) require little digestion. Glucose and fructose can be directly absorbed into the bloodstream without digestion.

Functional foods are required to simultaneously satisfy the 'sweet tooth' that the modern diet has created, and have a significantly higher energetic assimilation cost compared to today's sugar sweetened foods. This can be achieved by adding protein and fiber to e.g. SSBs, honey, syrup, jam, cereal products and ice cream (Table II)¹³.

Table 2. Sugar, protein and fiber content of a selection of sweet foods and drinks (value per 100 grams)

Protein has more than three times the thermic effect of either fat or carbohydrate²¹ and because it has a greater satiety value than fat or carbohydrate^21,22, a high protein diet (protein and carbohydrate intake both being approximately one third of total energy intake) is of vital importance as a weight-loss strategy for the overweight or obese and for weight maintenance^1,23.

Clinical trials have shown that calorie-restricted, high-protein diets are more effective than are calorie-restricted, high-carbohydrate diets in promoting^24-26 and maintaining²⁷ weight loss in overweight subjects, while producing less hunger and more satisfaction²⁸. Furthermore, high protein diets have been shown to improve metabolic control in patients with type 2 diabetes^29-31. Some protein based nanotubes are food-grade materials³² and can increase protein consumption at the expense of lowered carbohydrate.

Cooking has obvious beneficial effects by increasing food safety and improving diet quality³³. However, cooking can reduce the water content of a high energy dense processed food and thus, further increase its deleteriously high energy density, especially if it is cooked twice. For example, toasting whole-wheat bread increases its energy density from 2.5 kcal g^-1 to 3.1 kcal g^-1 as water content decreases by 14% (data calculated from USDA National Nutrient Database for Standard Reference).

Nanoscale science and technology are now enabling us to understand many natural and unnatural processes. Studying nanostructures at the cell and DNA level, gives us insight in to the working of these processes and how to manipulate, prevent and/or enhance them for the benefit of mankind. Emergent technologies can and must help correct the food system by creating modern convenience foods on a mass scale that mimic and improve on the nutritional value of the most nutritious cooked wild foods for humans. Thus, helping to prevent mental ill health, heart disease, cancer, obesity and other postprandial insults^1,4.

References

1. Robson, A.A. (2009). Preventing diet induced disease: bioavailable nutrient-rich, low-energy-dense diets. Nutr Health 20, 135-166.
2. Ledikwe, J.H., Blanck, H.M., Kettel Khan, L., Serdula, M.K., Seymour, J.D., Tohill, B.C., Rolls, B.J. (2006). Dietary energy density is associated with energy intake and weight status in US adults. Am J Clin Nutr 83, 1362-1368.
3. Robson, A. (2006). Shellfish view of omega-3 and sustainable fisheries. Nature 444, 1002
4. Robson, A.A. (2010b). Nanotechnologies and food: 1st report of session 2009-10: Vol. 2 Evidence. In House of Lords papers 22-II 2009-10, pp. 336-361.
5. Marean, C.W., Bar-Matthews, M., Bernatchez, J., Fisher, E., Goldberg, P., Herries, A.I.R., Jacobs, Z., Jerardino, A., Karkanas, P., Minichillo, T., Nilssen, P.J., Thompson, E., Watts, I., Williams, H.M. (2007). Early human use of marine resources and pigment in South Africa during the Middle Pleistocene. Nature 449, 905-908.
6. Wang, Y., Lehane, C., Ghebremeskel, K., Crawford, M.A. (2010). Modern organic and broiler chickens sold for human consumption provide more energy from fat than protein. Public Health Nutr 13, 400-408.
7. Eaton, S.B., Konner, M.J., Cordain, L. (2010). Diet-dependent acid load, paleolithic nutrition, and evolutionary health promotion. Am J Clin Nutr 91, 295-297.
8. Farhang, B. (2007). Nanotechnology and lipids. Lipid Technology 19, 132-135.
9. Hsieh, Y.H.P., Ofori, J.A. (2007). Innovations in food technology for health. Asia Pac J Clin Nutr S16, 65-73.
10. World Health Organization (2009). Micronutrient deficiencies: Iron deficiency anaemia http://www.who.int/nutrition/topics/ida/en/print.html.
11. Gerrior, S., Bente, L. (2002). Nutrient content of the U.S. food supply, 1909-99: a summary report US Department of Agriculture, Home Economics report no. 55, Washington, DC.
12. Watanabe, F. (2007). Vitamin B-12 sources and bioavailability. Exp Biol Med 232, 1266-1274.
13. Robson, A.A. (2010a). Food nanotechnology: water is the key to lowering the energy density of processed foods. Nutr Health (in press).
14. Ortiz, J., Romero, N., Robert, P., Araya, J., Lopez-Hernandez, J., Bozzo, C., Navarrete, E., Osorio, A., Rios, A. (2006). Dietary fiber, amino acid, fatty acid and tocopherol contents of the edible seaweeds Ulva lactuca and Durvillaea antarctica. Food Chem 99, 98-104.
15. Harun, R., Singh, M., Forde, G.M., Danquah, M.K. (2010). Bioprocess engineering of microalgae to produce a variety of consumer products. Renewable & Sustainable Energy Reviews 14, 1037-1047.
16. Chen, L., Remondetto, G.E., Subirade, M. (2006). Food protein-based materials as nutraceutical delivery systems. Trends in Food Science & Technology 17, 272-283.
17. Chen, L.W., Appel, L.J., Loria, C., Lin, P.H., Champagne, C.M., Elmer, P.J., Ard, J.D., Mitchell, D., Batch, B.C., Svetkey, L.P., Caballero, B. (2009). Reduction in consumption of sugar-sweetened beverages is associated with weight loss: the PREMIER trial. Am J Clin Nutr 89, 1299-1306.
18. U.S. Department of Agriculture (2008). Nutrient Intakes from Food: Mean Amounts Consumed per Individual, One Day, 2005-2006. Agricultural Research Service www.ars.usda.gov/ba/bhnrc/fsrg.
19. Institute of Medicine (2005). Dietary reference intakes for carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids. National Academies Press; Food and Nutrition Board. Washington, DC
20. Eaton, S.B., Konner, M.J., Cordain, L. (2010). Diet-dependent acid load, paleolithic nutrition, and evolutionary health promotion. Am J Clin Nutr 91, 295-297.
21. Crovetti, R., Porrini, M., Santangelo, A., Testolin, G. (1998). The influence of thermic effect of food on satiety. Eur J Clin Nutr 52, 482-488.
22. Stubbs, R.J. (1998). Appetite, feeding behaviour and energy balance in human subjects. Proc Nutr Soc 57, 341-356.
23. Veldhorst, M., Smeets, A., Soenen, S., Hochstenbach-Waelen, A., Hursel, R., Diepvens, K., Lejeune, M., Luscombe-Marsh, N., Westerterp-Plantenga, M. (2008). Protein-induced satiety: Effects and mechanisms of different proteins. Physiol Behav 94, 300-307.
24. Baba, N.H., Sawaya, S., Torbay, N., Habbal, Z., Azar, S., Hashim, S.A. (1999). High protein vs high carbohydrate hypoenergetic diet for the treatment of obese hyperinsulinemic subjects. Int J Obes 23, 1202-1206.
25. Skov, A.R., Toubro, S., Ronn, B., Holm, L., Astrup, A. (1999). Randomized trial on protein vs carbohydrate in ad libitum fat reduced diet for the treatment of obesity. Int J Obes 23, 528-536.
26. Layman, D.K. (2003). The role of leucine in weight loss diets and glucose homeostasis. J Nutr 133, 261S-267S.
27. Westerterp-Plantenga, M.S., Lejeune, M., Nijs, I., van Ooijen, M., Kovacs, E.M.R. (2004). High protein intake sustains weight maintenance after body weight loss in humans. Int J Obes 28, 57-64.
28. Johnston, C.S., Tjonn, S.L., Swan, P.D. (2004). High-protein, low-fat diets are effective for weight loss and favorably alter biomarkers in healthy adults. J Nutr 134, 586-591.
29. Seino, Y., Seino, S., Ikeda, M., Matsukura, S., Imura, H. (1983). Beneficial-effects of high protein-diet in treatment of mild diabetes. Human Nutrition-Applied Nutrition 37, 226-230.
30. Odea, K. (1984). Marked improvement in carbohydrate and lipid-metabolism in diabetic australian aborigines after temporary reversion to traditional lifestyle. Diabetes 33, 596-603.
31. Odea, K., Traianedes, K., Ireland, P., Niall, M., Sadler, J., Hopper, J., Deluise, M. (1989). The effects of diet differing in fat, carbohydrate, and fiber on carbohydrate and lipid-metabolism in type-II diabetes. J Am Diet Assoc 89, 1076-1086.
32. Graveland-Bikker, J.F., De Kruif, C.G. (2006). Unique milk protein based nanotubes: food and nanotechnology meet. Trends in Food Science & Technology 17, 196-203.
33. Carmody, R.N., Wrangham, R.W. (2009). The energetic significance of cooking. J Hum Evol 57, 379-391.

Copyright AZoNano.com, MANCEF.org