preparation and quality control of organic and designer

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Preparation and quality control of Designer and Organic egg K.GURU MOHAN REDDY TVM/2016-13 DEPARTMENT OF ANIMAL NUTRTION COLLEGE OF VETERINARY SCIENCE, TIRUPATI SRI VENKATESWARA VETERINARY UNIVERSITY

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Preparation and quality control of Designer and Organic egg

K.GURU MOHAN REDDYTVM/2016-13

DEPARTMENT OF ANIMAL NUTRTIONCOLLEGE OF VETERINARY SCIENCE, TIRUPATI

SRI VENKATESWARA VETERINARY UNIVERSITY

DESIGNER EGG PRODUCTION

Introduction

• The growing role of human nutrition in both the treatment and

prevention of chronic diseases has led to the convergence of the

consumer and governmental attention on the nutritional quality of

foods.

• The food industry has responded to the demand for foods of superior

health benefits by modifying the nutritional profile of popular foods

like eggs and meat.

• Consumer awareness on the relationship between dietary lipid and

the incidence of Coronary Heart Disease (CHD) changed their attitude

towards egg and meat consumption.

• The per capita consumption of egg and meat has not increased in

required number and quantity, respectively, through the years

because of the fear that egg yolk and meat contain high cholesterol.

• Due to unsuccessful attempts to significantly reduce cholesterol

content of eggs through genetic, nutritional, pharmacological tools,

researchers have turned towards using the egg and meat as vehicle

for delivering essential nutrients that were traditionally absent or in

low concentration in those products.

• With the focus on concepts such as the glycemic index, macronutrient

ratios and food groups, essential fatty acids (EFA) are one of the most

neglected aspects of nutrition in modern society.

• Even though a diet that is nutritious by most standards can be deficient in

polyunsaturated fatty acids (PUFA), omega-3 fatty acids are of particular

importance to the present day enlightened consumers.

Designer food

• The health promoting effects of dietary PUFA have provoked considerable

effort to enrich animal products using various sources of PUFA.

• The poultry industry in particular has been seeking newer technologies to

exploit products beyond their traditional food value.

• One such technology is DESIGNER FOOD (MEAT/EGGS), which can be

defined as a nutritionally modified functional or designer food, which

retains its functional, nutritional and sensory qualities but has a

significantly altered lipid profile.

Cholesterol scare

• Egg is a cholesterol rich food. A large egg contains about 210 mg of

cholesterol.

• Assumptions like egg consumption will increase the serum cholesterol

levels directly, many have reduced the egg consumption.

• This "cholesterol phobia" has scared the people in developed countries

until 1990 and still continued to do so in developing countries including

India due to ignorance; leading to low egg consumption.

• Even though the nutritional superiority of the egg has been proved beyond

doubt, the egg consumption in India is very low due to vegetarianism as

well as cholesterol scare.

• Although the nutritionists and cardiologists have established that there is

only an insignificant correlation between dietary and serum cholesterol

levels;

• The consumers are still scared of consuming cholesterol rich foods, hence

there is an urgent need to reduce the egg yolk cholesterol levels as well as

to incorporate several other health promoting components in the egg.

• The industry is presently geared in production of specialty eggs that have

higher or enriched levels of certain nutrients already present in the eggs or

lower the levels of other nutrients, which are considered undesirable for

some reasons.

• Such eggs are called “designer eggs", “functional eggs”, “diet eggs”,

“omega-3 fatty acid enriched eggs”, which are capable of safeguarding the

health of the consumers.

• The designer egg will be produced with rich health promoting components

like omega-3 fatty acids and vitamin E along with incorporation of some

more additional health promoting components, like anti-oxidants,

carotenoid pigments, certain vitamins and minerals; besides reducing the

yolk cholesterol levels.

• In general, omega-3 fatty acids reduced the LDL-Cholesterol (Bad

cholesterol) levels in serum, thereby reducing the risk of cardiovascular

diseases. Further they scavenge the free radicals and act as

immunomodulators in the persons, consuming such eggs regularly

Designer Eggs

• "Designer eggs" are those in which the content has been modified

from the standard egg.

• Developed due to problems arising out of HIGH CHOLESTROL LEVEL

and SALMONELLA.

• The concept was put forward by Dr. J. Sim of University of Alberta ,

N.A.

• Production of Designer Eggs egg quality can Modifying be

accomplished by:

• Inducing metabolic changes in the hen that can result in synthesis of

compounds that essentially end up in her egg.

• Change the characteristics of membrane transport to facilitate

movement of compounds into the egg.

Nutrient content:

• Vitamin content ,

• Lowered Cholesterol and Fat content,

• Mineral content ,

• Pigment content ,

• Pharmaceutical content.

Vitamin content

• Depends on dietary concentration of any specific vitamin.

• Have 26 times more Vitamin E.

• Have 16 times higher CAROTENOID content.

• Have 7 times greater SELENIUM content.

Lowered Cholesterol

• Depends on diet and Pharmacological Intervention.

• Drugs like PROBUCOL have lowered the egg cholesterol by 50 %.

• Such eggs have 29% less saturated fat.

• Other methods : -Chromium supplementation and Lowering the Fat

content

Lowering the Fat Content

• Depends on feed of flaxseed ,marine algae ,fish oil and vegetable oil.

• Have higher amount of omega-3 fatty acid.

• High amount of Iodine.

• Have lowered saturated to unsaturated fatty acid ratio

Mineral content:

• Done by feeding diet rich in zinc, copper, iodine, chromium and selenium content.

• Calcium and phosphorus content of the shell is enhanced in these eggs.

Pigment content:

• Depends on the dietary concentration of any particular pigment.

• Consumer preferences vary greatly according to yolk color.

• pigmented yolks are used in bakery products , pasta and mayonnaise.

Pharmaceuticals:

• Produced by genetic modification of chickens

• Compounds like Insulin and antibodies are being produced by this

method

• Production of antivenoms and protection from tooth decay.

Specialty of Designer Eggs:

• Alternative choices to consumers with special needs and preferences.

• Nutrient content of an egg can be changed only by altering the hen’s

feed.

• Nutrient content cannot be altered by changing environmental

conditions.

• Due to higher production costs, specialty eggs are usually more

expensive than generic shell eggs.

Designer eggs-Significance

• In general, eggs are regarded as highly nutritious food.

• The egg is considered as nature’s most complete food containing high

quality proteins, a 2 to 1 ratio of unsaturated fats to saturated fats an

excellent source of iron, phosphorus and other minerals and all

vitamins with the exception of vitamin C.

• The antibacterial components in the egg and their contribution to

food safety is an acknowledged fact.

Omega-3 PUFA

• Omega-3 fatty acids are a group of polyunsaturated fatty acids (PUFA)

also known as n-3 fatty acids.

• n-3 denotes the position of the first double bond in the carbon chain

starting from the methyl end of the molecule being on the third

carbon atom.

• Majority of birds and animals including human beings cannot

synthesize these n-3 fatty acids, hence they are dietary essential.

• Designer egg is rich in Omega-3 (or) n-3 fatty acids such as

Alpha- Linolenic acid (ALA) : C18 : 3n-3

Eicosapentaenoic acid (EPA) : C20 : 5n-3

Docosahexaenoic acid (DHA) : C22 : 6n-3

• Unfortunately, the foodstuffs rich in these n-3 fatty acids namely linseed

and fish oils are having undesirable flavor and consistency, hence not

relished commonly by human beings.

• They can be made acceptable by incorporating these beneficial n-3 fatty

acids into eggs.

Sources of Omega-3 fatty acids

• Sardine fish

• Anchovy Fish

• Fish oil

• Linseed/Flaxseed & oils

• Rapeseed/Canola & oils

• Pearl Millet

• Algae

Clinical Significance – Omega-3 Fatty acids

• With the pioneering discovery of the fact that omega-3 fatty acids

was responsible for the lesser incidence of Coronary Heart Disease

(CHD) in Greenland Eskimos, whose staple diet is the fish.

• Research over the past decades on the various health benefits of

dietary omega-3 fatty acids from fish oils, has shown that omega-3

fatty acids are essential nutrients for adults and children alike.

• The dietary omega-3 fatty acids reduce plasma triglycerides, blood

pressure, platelet aggregation, thrombosis and atherosclerosis

particularly in diabetics , tumor growth, skin disease and enhance

immunity.

• The potential health benefits of n-3 fatty acids in human diet have

also drawn attention and altering the fatty acid composition of the

egg and tissue through dietary ingredients.

Designer egg evaluation in a controlled trial

• Objective: To evaluate the ability of designer eggs enriched in

vitamin E, lutein, selenium (Se) and docosahexaenoic acid (DHA) to

deliver micronutrients to the human in a palatable and visually

acceptable form.

• Design: Double-blind, placebo-controlled trial, two treatment groups

balanced for sex and age.

• Setting: Department of Biochemistry and Nutrition, SAC, Scotland.

• Interventions: Volunteers consumed, for 8 weeks, either a designer

egg or a normal table egg per day. Fasting blood samples were taken

before and at the end of the study.

• Results: Consumption of designer eggs enriched in vitamin E, lutein,

Se and DHA signi®cantly increased the levels of a-tocopherol, lutein

and DHA in plasma as compared to the changes found after

consumption of normal table eggs, with the largest increases found in

plasma lutein (1.88-fold increase).

• The proportion of DHA was increased in all the main lipid classes of

the plasma including triacylglycerol (2.3-fold), free fatty acids (1.6-

fold), cholesteryl ester (1.4-fold) and phospholipid (1.3-fold).

• Egg consumption did not change Se concentration in plasma, blood

pressure, total plasma lipid concentrations or the concentrations of

total cholesterol and HDLcholesterol in plasma.

• Conclusion : Consumption of designer eggs enriched in vitamin E,

lutein, DHA and Se as part of normal diet for 8 weeks effectively

increased the blood levels of a-tocopherol, lutein and DHA.

Organoleptic quality of omega-3-enriched eggs

• The organoleptic quality of omega-3 eggs tends to be similar to regular

table eggs although in some cases panellists are able to detect off-flavours .

• A ‘fishy’ or fish-product related flavor was detected in eggs from hens on

diet containing 15–20% flax seed and the data of Leeson et al. also suggest

that high (>10%)level s of flax seed will result in some decrease in overall

egg acceptability as assessed by aroma and flavor.

• It has been suggested that the use of combinations of anti-oxidants in

the hen’s diet could help to suppress these off-flavours ; however,

high levels of vitamin E did not prevent the formation of off-flavours

in hens fed on the high (>10%)flax diet.

• In general, therefore, fishy taints in eggs are not detectable provided

that the hens are fed 5% (or less) flaxseed or low levels of a high

quality oil, e.g. 1.5% (or less)men had en fish oil .

• In this respect, a dried DHA-enriched marine micro-algal product

showed promising results.

• The fishy taint can result from rancidity of the n-3 enriched diet,

therefore the quality of oils used is important in eliminating off-flavor

in eggs.

• While the oil can be protected with anti-oxidants or micro-

encapsulated once the oil is oxidized the addition of anti-oxidants will

not reverse this situation.

• It is notable that the acceptability of ‘fishy’ taints varies from country

to country.

• For example, eggs produced in some countries (Chile), where fish

meal as well as fish oil are usual components of the chicken diet,

contain quite high level of DHA and in many cases have a fishy taste

(personal experience of PFS).

• Generally, the public in Chile are used to this taste and accept it as

normal while, for Europeans, for example, it would be unacceptable.

Cooking characteristics of omega-3 eggs:

• Emulsification capacity, hardiness and springiness of sponge cakes

prepared using these eggs, were the same as in ordinary eggs .

• Data on effects of n-3 enrichment on egg quality during storage are

limited and sometimes contradictory.

• For example, it has also been shown that there is no alteration in fatty

acid profile of eggs enriched with n-3 PUFAs during cooking or during

storage for 7 weeks at 25C whereas other studies have reported an

increased susceptibility to oxidation during storage and cooking.

• Enrichment of egg yolk in vitamin E is thought to be an effective

means to significantly decrease thiobarbituric acid values(TBARS)

in n-3-enriched eggs.

• In other experiments, yolk TBARS values in n-3-enriched eggs were

not significantly different from those in control eggs.

• However, it needs to be recognized that this parameter depends on

the analytical technique used and the level of the egg enrichment

with n-3 PUFA.

• Therefore attention needs to be paid to the organoleptic properties of

n-3-enriched eggs and in particular the relationship between n-3

levels and organoleptic quality.

Types of Specialty Eggs:

• Organic Eggs,

• VegetarianEggs ,

• Aracauna Eggs ,

• Pasteurized Shell Eggs,

• Fertile Eggs,

• Cage-Free Alternatives United Egg Producers Certified Eggs.

Organic eggs• The National Organic Standard Board (USDA)in October 2002 set

national guidelines for producers.

• Produced by hens given feed grown without most conventional

pesticides , fungicides, herbicides, or commercial fertilizers.

• Use of growth hormones and antibiotics is prohibited.

• Produced by free roaming hens

Organic egg production

• It is the production of eggs through organic means.

• In this process, the poultry are fed organic feed.

• According to the United States Department of Agriculture, organic

means that the laying hens must have access to the outdoors and

cannot be raised in cages.

• Organic egg producers cannot use antibiotics except during an

infectious outbreak.

• Only natural molting can occur within the flock; forced molting is not

allowed.

• Organic certification also requires maintenance of basic animal

welfare standards.

Differences between "free range" and "organic"

• Significant differences cover feed, medication, and animal welfare.

• Organic hens are fed organic feed; it is prohibited to feed

animal byproducts or GMO crops – which is not disallowed in free

range environments.

• No antibiotics allowed except in emergencies (in free range, it is up to

the farmer, but the same levels of antibiotics as conventional farming

is allowed).

• Required animal welfare standards in organic farms are higher, which

can improve the quality of both the eggs and the meat.

• In the European Union (EU), to identify and trace egg production, a

unique code must legally be printed on all eggs.

• A “0” code distinguishes organic farming eggs.

Organic feed

• Organic feed is grown without the use of genetically modified

organisms (GMOs), synthetic fertilizers, pesticides or herbicides.

• It is often grown by certified organic farmers, whose practices are

monitored for three years prior to being certified organic.

• If the crop is contaminated by cross-fertilization with GMOs, it is

rendered useless for organic grading.

• Finally, there can be no animal by-products in organic feed.

Vegetarian Eggs:

• Diet containing only ingredients of plant origin.

• Nutrient content of these eggs is the same as that of regular eggs.

Aracauna Eggs:

• From Aracauna chickens, native to South America.

• Color -bluish-green eggs

• Eggs from this breed have a higher cholesterol content.

• Nutritionally, not much different from traditional white and brown eggs.

Pasteurized Shell Eggs:

• Heat treated to kill potential salmonella bacteria found inside.

• Due to the heat processing, these eggs may have slightly lower levels

of heat sensitive vitamins.

• Packaged in liquid, frozen or dried form.

• Used in recipes like home made ice-cream or in Caesar salad dressing

Fertile Eggs:

• Some cultures consider fertile eggs a delicacy.

• No nutritional difference between fertile eggs and generic eggs.

• Thoroughly cooking generic shell eggs destroy any potential

salmonella bacteria in the egg.

Cage-Free Alternatives:

• Housed in large laying facilities that use cage systems.

• Provides hens with optimal temperature, humidity, feed, water, laying

space, and security.

• Designed for the welfare of the birds as well as for production

efficiency.

United Egg Producers Certified Eggs :

• New animal welfare standards that improve the care and handling of

egg-laying hens.

• Hens living in humane conditions with attention to living

environment, health care, and treatment.

• Animal welfare and health were important factors considered in

producing the eggs