IMPORTANCE OF DESIGNER EGGS
Siddharth Savale*, Dhanraj Girimal, Udaykumar, Vidyasagar, Shivkumar Kamthane, Gurunath Pasare and Satishchandra Biradar
*Veterinary Officer, Veterinary Dispensary Sonal, Bidar Karnataka
ph.no. 9497793263
Eggs are most popular source of proteins for humans. Due to their nutrient profile, variety and low costs as food, eggs are one of the most popular foods across the world. Animal products contribute to total lipids, cholesterol and saturated fatty acid intakes in human diets. Nowadays, retail markets for functional eggs are already present, mainly those enriched with omega-3 PUFA (poly unsaturated fatty acids) or with low content of cholesterol. Generally, these eggs are produced by modifications in layer diets, whereas much less attention has been paid to the development of designer eggs by means of technological methods. Designer eggs can provides more than 600 mg omega-3 PUFA and 6 mg tocopherol. There are further beneficial impacts for egg consumers due to its balanced ratios of omega-6/omega-3 PUFA (1:1) and PUFA/SAFA (1:1). Therefore, the functional egg may give an alternative choice of food product to egg consumers around the world. Designer eggs are available in global markets with different names according to geographical area like the Columbus eggs, Eggs Plus, docosahexaenoic acid (DHA) enriched eggs, omega 3 eggs, Bio-omega 3 eggs, England’s best, Greek eggs, Baby eggs, Achyrona Ωmega eggs and omega-3 herbal eggs, sometimes tied in to rearing methods, e.g. organic production. The egg industry has responded well in seeking new techniques to improve the negative perceptions of consumers about problems of eggs and their products, particularly the cholesterol content. The following review focuses on the concept, production and nutritional values of designer eggs. It describes the significance of designer eggs and their health benefits for human consumers. The information provided is relevant for nutritionists, researchers, scientists and veterinarians and, most importantly, for consumers who are the main stakeholders.
Production of designer eggs
Proteins from eggs are highly digestible and contain the important essential amino acids. However, the nutrients present in eggs are not optimised compared with the recommended intake in humans for improved health status. A large number of these nutrients in eggs can be improved by modifying dietary compositions, e.g. vitamin E, omega 3 fatty acids, selenium and carotenoids. The composition and nutrient density of poultry diets can affect composition and nutritional quality of eggs and their products. For example, if an animal is fed on a diet that is deficient in certain nutrients, the products from those animals will also contain sub-normal concentrations of these nutrients. Using a well-balanced ration in poultry enhances the performance, carcass and meat quality as well as food safety. The production of functional foods requires careful application of diet formulation in poultry, and the nutritive values of ingredients must be adequate to have an impact on public health and welfare as well as to ensure good quality poultry products.
Significance of designer eggs
The concept of designer eggs has been introduced with the aim to improve the consumption of egg in the food market. A normal egg provides 70 kcal of energy in the form of proteins, carbohydrates, fatty acids, amino acids, fats, cholesterol and PUFAs as well as potassium, sodium and contributes to platelet inhibition, anti-ACEI and anti-ROS activities. Eggs contain antiinflammation and anti-coagulation components, and contain anti-hypertensive peptides like ovokinin along with 12 important minerals and vitamins, which can help to protect organs such as the heart from many diseases. Eggs are a cheap source of high quality protein along with balanced ratio of vitamins (except vitamin C) and minerals but due to high content of cholesterol (200 mg/egg). Improvements of nutrients generate today’s so-called ‘functional or designer eggs’, which have been used to achieve the different goals which are discussed below.
Lowering cholesterol
Addition of PUFA in poultry diets significantly reduces cholesterol and total lipids content. A few studies suggest that egg cholesterol could be decreased by 25% using combinations of dietary strategies. Supplementation with the Gynura procumbens plant in laying hen diets decreased cholesterol by 12% in egg yolk. yolk cholesterol was lowered by feeding low-fibre alfalfa meal.
Eggs enriched with minerals and vitamins
Dietary manipulation makes it is possible to improve the level of iodine, selenium, and chromium in eggs without affecting the important calcium and phosphorus level. Most minerals are found in in the shell, comprising large concentrations of calcium and phosphorus. In fact, the production of selenium-enriched eggs is very simple and can be achieved by inclusion of 0.4 mg/kg as Se yeast to produce an egg containing about 30 mg of selenium which is approximately 50% of RDI. The inclusion of designer eggs into the human diets by 12 to 16 eggs per month increased vitamin E consumption up to the level of 23 mg per day.
Improved fatty acid profile
Markets exist for designer eggs with lower ratios of saturated to unsaturated fatty acids. This ratio is commonly altered by using canola oil in the feed. Designer eggs offer balanced ratios of PUFA/SAFA (1:1) or omega-6/omega-3 PUFA (1:1). Omegas 3 PUFA are important nutritional factors that modulate the immune function and are important for developing nervous system. They lower blood platelet aggregation, incidence of thrombosis, blood pressure and atherosclerosis, in addition to their antitumor, antiinflammatory and cardioprotective effects. The egg contents of omega-3 fatty acids can be raised by supplementing the diets of laying hens with certain dietary supplements, for example, from groundnut oil, fish oil, safflower oil, linseed, fish meal or algae.
Antibodies and other products:
Novel biotechnology facilitates the process of developing genetically modified chickens that could be used to produce eggs with benefits such as insulin for diabetes treatment and variable antibodies that could be used in treatment of microbial toxins and snake venoms. Transgenic hens could be used to produce antibodies in their egg´s albumin.
Enrichments of bioactive components:
Enrichment of bioactive components in eggs is a more recent trend. These bioactive components can have health benefits in humans. The intake of phytoestrogens needed to achieve a biological effect in humans seems to be 30-50 mg/d (Setchell, 2003) and one egg per day provides about 25% of isoflavones requirements.
Conclusions and future perspectives
Diet is one of the most important factors that have significant influences on the health, and eggs can provide a useful vehicle for increasing intake of important nutrients to humans. This has resulted in efforts to develop dietary components with high nutritive values that could modulate the body immune functions, treat some diseases and health problems such as cancer and diabetes, regulate blood pressure, decrease cholesterol level and alleviate cardiac problems and allergies. The health benefits from designer eggs needs to be highlighted by appropriate labeling on final packaging.
