n-3 Fatty Acid Enriched Table Eggs: A Survey of Consumer Acceptability

n-3 Fatty Acid Enriched Table Eggs: A Survey of Consumer Acceptability A. C. MARSHALL,1 K. S. KUBENA,2'3 K. R. HINTON,1 P. S. HARGIS,1*3 and M. E. VAN ELSWYK1'3-4 Departments of Poultry and Animal Science, Graduate Faculty of Nutrition, Texas Agricultural Experiment Station, Texas A&M University System, College Station, Texas 77843-2472

1994 Poultry Science 73:1334-1340

INTRODUCTION Coronary heart disease (CHD) is one of the leading causes of death in America. Risk factors for CHD include hypertension, obesity, and elevated blood cholesterol. Many of the risk factors for CHD are responsive to dietary changes and are particularly responsive to fat modifications in the diet. This responsiveness has been demonstrated by a number of clinical and epidemiological studies, including a classic study by Bang and

Received for publication December 20, 1993. Accepted for publication March 30, 1994. 'Department of Poultry Science. department of Animal Science. 3 Graduate Faculty of Nutrition. 4 To whom correspondence should be addressed.

Dyerburg (1972). These authors found that, in spite of a rather high intake of dietary fat, Greenlandic Eskimos rarely suffered from ischemic heart disease. They found this phenomenon to be due to the "unique fatty acid composition" of the Eskimos' diet: a high intake of n-3 fatty acids found in fish (Bang and Dyerburg, 1972). Unlike Eskimo diets, the typical American diet is rich in n-6 fatty acids. The metabolism of n-6 fatty acids results in the production of pro-inflammatory eicosanoids, which encourage platelet aggregation (Harris, 1989; Kromhout, 1992). Differences in structure, specifically double bond location, distinguish n-3 fatty acids from n-6 fatty acids and are responsible for their unique metabolism. The metabolism of n-3 fatty acids results in the

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ABSTRACT Table eggs enriched with n-3 fatty acids may provide an alternative to fish as a source of these proposed healthful fatty acids. Successful marketing of this product may be influenced, however, by consumer perceptions of the egg as an unhealthful food. Therefore, the objectives of the current study were to assess consumer perceptions of table egg health quality and to determine the potential consumer acceptability of an n-3 fatty acid-enriched table egg. A survey was conducted in five major Texas cities; over 500 consumers completed the survey. Data were analyzed using the chi-square procedure. The majority of consumers surveyed considered eggs healthful and reported purchasing eggs at least once monthly and consuming an average of three whole eggs per week, as compared with an average reported fish consumption of only one serving per week. Sixty-five percent of the consumers reported willingness to purchase an n-3 fatty acid-enriched table egg and of these, 71% were willing to pay an additional $.50 per dozen. These data indicate that n-3 fatty acid-enriched table eggs represent a viable means of incorporating n-3 fatty acids into the diet of health-conscious consumers. {Key words: table eggs, n-3 fatty acids, consumer survey, product marketability, egg consumption)

CONSUMER ACCEPTANCE OF n-3 FATTY ACID-ENRICHED TABLE EGGS

Because the decline in shell egg consumption over the past decade may be related in part to consumer concern with cholesterol intake, eggs may be perceived as an unhealthful food. In addition, the decline in breakfast consumption and the perception of the egg as an inconvenient food also may have contributed to the decline. Market research, therefore, is needed to determine consumer perception of shell eggs health quality, as well as perception of their usefulness. Such research is necessary for the development of marketing strategies for this potentially beneficial n-3 fatty acid-enriched shell egg. Therefore, the objectives of the current study were to determine 1) consumer perceptions of table egg health quality, 2) current food purchasing practices, and 3) consumer willingness to purchase an n-3 fatty acid-enriched shell egg.

MATERIALS AND METHODS Survey Design A 25-question, self-administered survey was developed and pilot-tested at Texas A&M University, after which final modifications were made. Primarily composed of closed-ended questions, the survey also included open-ended questions to allow consumers to share their opinions. Openended questions were not analyzed statistically. Four closed-ended demographic questions were placed at the end of the survey to provide information on age, sex, ethnicity, and income. A cover sheet was included to assure consumers of the confidentiality of the survey and to introduce them to the study. The survey was conducted in five Texas cities: Austin, BryanCollege Station, Dallas, Forth Worth, and Houston. One hundred surveys were collected in each city, 50 from a typical grocery store and 50 from a health food store. Participants were given a designer cup or specialty pencil for their participation in the survey. Consumers were also provided with a number of pamphlets concerning eggs and their usefulness. The survey was conducted in the fall of 1992, primarily on Saturdays and Sundays. Statistical Analysis Survey responses were coded and entered into a computer database file. Due to the categorical nature of the data, results were analyzed using the chi-square goodness-of-fit test (Keller et al, 1988). Chisquare values were calculated without the aid of a computer due to the prevalence of cell counts below five. Significance is reported at P < .01 and P < .001. RESULTS Responses to demographic questions were comparable to Texas census data (Table 1). The demographic data indicated that 53% of the consumers were between the ages of 25 and 44, 60% were female, 50% reported an annual income of $35,000 or less, and 73% were of Caucasian ethnic origin. Table 2 represents the responses when consumers were asked, "Do you feel

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production of eicosanoids with greatly reduced capacities to induce inflammatory responses or stimulate the aggregation of platelets (Harris, 1989). Thus, an increased dietary intake of n-3 fatty acids has been recommended as a means of reducing risk for CHD (Kromhout, 1992). Current dietary recommendations include consumption of one to two fish meals each week (Kromhout, 1992). Unfortunately, current national consumption levels of fish approximate one serving per week (USDA-Economic Research Service, 1992). Due to this relative dietary n-3 fatty acid insufficiency, research efforts have been initiated to seek alternative food sources of these healthful fatty acids (Hargis et ah, 1991; Oh et al, 1991). The egg has been targeted as such an alternative food source due to the fact that the unsaturated fatty acid composition of the egg is readily responsive to changes in the diet of the hen (Naber, 1979). Inclusion of various fish oils, seeds, and seed oils in layer rations readily results in the incorporation of up to 220 mg of n-3 fatty acids per egg yolk (Hargis and Van Elswyk, 1993). This level of n-3 fatty acids is equivalent to that which would be consumed in a 100-g (3.5-oz) serving of lean fish; therefore consumption of one n-3 fatty acid-enriched shell egg potentially could replace consumption of a fish meal.

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MARSHALL ET AL. TABLE 1. Consumer-reported demographic data as compared to Texas census data1 Percentage of consumers

Variable Age (yr) 18 to 24 25 to 44 45 to 59 60 to 74 > 75 Sex

Texas census2

18 53 17 10 2

16 46 19 13 6

40 60

49 51

50 32 18 73 15 7 2 3

75 12 263 2 1

1

Source: 1990 Texas Census of Population and Housing (Bureau of the Census, 1991). Income data not available. 3 Hispanic origin of any race, as opposed to survey data, which use Hispanic origin as a separate ethnic origin. 2

knowledgeable about the fat and those consumers who perceived themcholesterol content of foods?" Nearly 80% selves as lacking knowledge. Knowledgeaof these consumers perceived that they ble consumers reported paying the most were, in fact, knowledgeable about the fat attention to food fat content, independent and cholesterol content of foods. Table 3 of cholesterol content (Table 3). One of the next questions asked was, combines responses from that question with those from the question, "Do you "Do you feel that eggs are unhealthy?" pay more attention to the fat or cholesterol Table 4 demonstrates the overwhelming content of food when you shop?" Con- number of responses indicating that these sumers who perceived themselves as consumers feel that eggs are healthful knowledgeable about the fat and rather than unhealthful. Table 5 demonstrates that an average 44% of consumers cholesterol content of food were less who feel that eggs are healthful purchase attentive to both these food components eggs either one time each week or two when purchasing foods, as compared with times each month (once every 2 wk). In order to completely assess the egg purchase frequency of the total population surveyed, categories of egg purchase frequency were ranked (less than once TABLE 2. Consumer perception of knowledge of the fat and cholesterol content of foods1 monthly = 1, more than twice weekly = 6) and a weighted average, using the perPercentage of centage of subjects choosing each catePerception consumers surveyed gory, was calculated. Weighted averages were compared using chi-square. There 78 Knowledgeable Lacking knowledge 22 was no difference in the average egg Chi-square 31.11"* purchase frequency between individuals 1 Question asked, "Do you feel knowledgeable that considered eggs unhealthful (mean = 4.18) and those that considered eggs about the fat and cholesterol content of foods?" healthful (mean = 3.89). ***P < .001, Chi-square goodness-of-fit test.

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Male Female Annual income up to $35,000 $36,000 to $60,000 $61,000 and above Ethnic origin Caucasian African American Hispanic Asian/Pacific Islander Other

Consumer survey

CONSUMER ACCEPTANCE OF n-3 FATTY ACID-ENRICHED TABLE EGGS

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TABLE 3. Attributes considered for food purchase based on consumer perception of knowledge of fat and cholesterol content of foods1 Percentage of consumers surveyed Food attributes Fat Cholesterol Both Neither

Knowledgeable

Lacking knowledge

45 22 13 20

35 18 42 5

Chi-square 1.22 .37 14.76*" 8.53**

1

The data for all respondents concerning egg purchase frequency were combined with the number of persons in each household and the number of eggs usually purchased at a time to determine the number of eggs consumed per person per day. This value was approximately onehalf egg per person per day or the equivalent of three eggs each week for all consumers surveyed. Thus, the level of reported shell egg consumption was three times higher than the reported level of fish consumption (Table 6). Seventy percent of the consumers surveyed reported consuming fish only one time weekly, less than one time weekly, or never. Additionally, less than one-third of the consumers surveyed consume fish at a level that meets dietary recommendations and this was significant (Table 6). Table 7 represents the responses to two questions. First, "Would you be willing to add n-3 fatty acids to your diet in a form

TABLE 4. Consumer perception of shell eggs: healthful vs unhealthful1

Perception

Percentage consumers surveyed

Healthful Unhealthful Chi-square

67 32 12.72***

Question asked, "Do you consider eggs unhealthy?" ***P < .001, Chi-square goodness-of-fit test.

other than fish?" Eighty percent of the consumers surveyed responded positively to that question. The second question asked, "Would you be willing to purchase an n-3 fatty acid-enriched egg?" A majority of the consumers (65%) indicated that they would be willing to purchase an n-3 fatty acid-enriched shell egg. It was anticipated that perhaps the responses from consumers in health food stores would reflect a greater interest in and willingness to purchase the enriched egg. However, the results indicate that there was no difference between the two groups of consumers (data not shown). When asked how much more they would be willing to pay for such a product (Table 8), 71% of the consumers indicated that they would be willing to pay up to $.50 more per dozen, and 35% indicated willingness to pay up to $1.00 more per dozen. Another potential market lies in further processed products that would be made using the n-3 fatty acidenriched egg. Table 9 represents consumer interest in any or all of the products shown. Although only 37% indicated a direct interest in the egg itself, 52% indicated an interest in cake or muffin mixes made with the enriched egg, and 69% indicated an interest in a mayonnaise or salad dressing made with the enriched eggDISCUSSION Demographic data correspond well to Texas census data (Bureau of the Census,

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Question asked, "Do you pay more attention to the fat or cholesterol content of foods when you shop?" **P < .01, Chi-square goodness-of-fit test. ***P < .001, Chi-square goodness-of-fit test.

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MARSHALL ET AL. TABLE 5. Egg purchase frequency based on perception of healthfulness of shell eggs 1 Percentage of consumers surveyed

Purchase frequency

Healthful

Unhealthful2

Chi-square

Less than once monthly Once monthly Twice monthly Once weekly Twice weekly More than twice weekly

3.00 2.00 21.00 23.00 14.00 6.00

2.00 1.00 7.00 8.00 5.00 8.00

.20 .40 17.10** 17.60** 9.60 .50

2

1991), although they are more likely representative of the population that shops on Saturday and Sunday. Ethnicity data are biased due to the fact that the survey was available only in English. Additionally, these data may indicate a trend toward traditional gender roles, as a larger percentage of respondents were female. Because the majority of the consumers surveyed (80%) reported that they perceive themselves to be knowledgeable about the fat and cholesterol content of foods, it is interesting to note that the "knowledgeable" consumers pay less attention to both the fat and cholesterol content of foods when they shop. Although this response may support previous research indicating that purchasing decisions are affected by flavor, cost, and product convenience more than by nutri-

tion (Stanley et al, 1991; American Meat Institute, 1992; Caswell and Padberg, 1992), recent research suggests that this trend is changing (Kim et al, 1992; Padberg et al, 1993). Furthermore, the new nutrition label, which specifies fat and cholesterol contents of foods, may influence the importance of these attributes in future food purchasing decisions. As nearly 70% of the consumers reported that they do not view eggs as unhealthful, consumer concern over dietary cholesterol may not be as great as in recent years. Surprisingly, the consumers who reported that they view eggs as unhealthful reported purchasing eggs as frequently as those who feel eggs are healthful. This may indicate that consumers who feel that eggs are unhealthful still feel that eggs are useful. The level of shell egg consumption compiled from

TABLE 6. Fish consumption frequency1

Consumption frequency

Percentage consumers surveyed

Never Less than once weekly Once weekly Twice weekly More than twice weekly Percentage meeting recommendation: Percentage not meeting recommendation: Chi-square

10 31 30 19 11 30 70 16.69***

1

Question asked, "How often do you and your family eat fish?" ***P < .001, Chi-square goodness-of-fit test comparing percentage meeting dietary recommendation for fish consumption vs the percentage not meeting the recommendation.

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Questions asked, "How often do you purchase eggs?" and "Do you consider eggs unhealthy?" Column headings represent "no" and "yes" responses to the question, "Do you consider eggs unhealthy?" **P < .01, Chi-square goodness-of-fit test. 2

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CONSUMER ACCEPTANCE OF n-3 FATTY ACID-ENRICHED TABLE EGGS TABLE 7. Interest in dietary n-3 fatty acids and in n-3 fatty acid-enriched eggs Percentage of consumers surveyed Variable 2

Add n-3 fatty acids to diet in form other than fish Buy an n-3 fatty acid-enriched egg3

Willing1

Unwilling1

Chi-square

77 65

23 35

28.35*** 9.00**

Column headings represent "yes" and "no" responses to the questions asked. Question asked, "Would you be interested in adding n-3 fatty acids to your diet in a form other than fish?" 3 Question asked, "Would you purchase an n-3 fatty acid enriched egg?" **P < .01, Chi-square goodness-of-fit test. ***P < .001, Chi-square goodness-of-fit test. 2

consumption levels, substitution of n-3 fatty acid-enriched shell eggs for regular shell eggs in the diet could result in the consumption of the equivalent of three fish meals weekly. These results indicate that there is a market for n-3 fatty acid-enriched shell eggs due to reported interest in adding n3 fatty acids to the diet. Willingness both to purchase and to pay more for n-3 fatty acid-enriched shell eggs indicates potential profitability for the poultry industry. Based on Texas census and egg consumption data and using an increased cost of $.50 more per dozen for n-3 fatty acid enriched eggs, if 65% of the consumers substituted enriched eggs for typical shell eggs, an extra $96 million in revenue may be realized by Texas alone. Reported interest in further processed products made with n-3 fatty acidenriched shell eggs indicates the presence

TABLE 8. Willingness to pay more for n-3 fatty acid-enriched eggs1 Percentage of consumers surveyed Additional cost

Willing

Unwilling

Chi-square

$.50 more per dozen $1.00 more per dozen $1.50 more per dozen $2.00 more per dozen

71 36 12 4

29 64 88 96

18.06*** 8.39** 56.55*** 86.45***

1

Question asked, "How much more would you be willing to pay for omega-3 fatty acid enriched eggs? $.50 more per dozen? $1.00 more per dozen? $1.50 more per dozen? $2.00 more per dozen?" Yes and no responses marked for each value. **P < .01, Chi-square goodness-of-fit test. ***P < .001, Chi-square goodness-of-fit test.

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survey data corresponds well to national consumption data (USDA-Economic Research Service, 1992). However, reported fish consumption was lower than national consumption levels, which approximate one fish meal per week (USDA-Economic Research Service, 1992). This low level of fish consumption was reported despite current recommendations that Americans consume fish two times weekly to reduce risk for CHD (Kromhout, 1992). In light of the difference between reported levels of consumption of shell eggs and fish, it is notable that consumption of n-3 fatty acidenriched table eggs instead of regular shell eggs could dramatically increase consumption of n-3 fatty acids. One n-3 fatty acid-enriched shell egg contains approximately the same amount of n-3 fatty acids found in a 100-g serving of a cold-water, lean fish (e.g., cod or orange roughy; USDA, 1986). Therefore, at reported egg

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MARSHALL ET AL.

TABLE 9. Interest in products made with enriched eggs1

Enriched egg products

Percentage consumers surveyed

Shell eggs Cake mixes or muffin mixes Salad dressings or mayonnaise

37 52 69

iQuestion asked, "Which of the following fatmodified products would you be interested in? Mark all you would be interested in."

REFERENCES American Meat Institute, 1992. Nutrition labels and meat: consumer knowledge, usage, and attitudes (report of a national consumer survey). The Roper Organization, New York, NY.

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of another potential market. Products like n-3 fatty acid-enriched mayonnaise and cake mixes are currently being sold in Europe, where 80% of the United States production of fish oil is sent (Bimbo and Crowther, 1992). These products potentially can be marketed in the United States, adding health value to further processed egg products. In conclusion, the majority of consumers do not consider eggs to be an unhealthful food. Therefore, there is a potential market for a health-value-added egg product such as the n-3 fatty acidenriched shell egg. Additionally, knowledgeable consumers are paying more attention to fat content rather than to cholesterol content of foods when they shop. This indicates that advertising for an n-3 fatty acid-enriched shell egg will need to focus on the improved fatty acid composition. Finally, consumer willingness to pay more for an n-3 fatty acidenriched shell egg could result in substantial profit for the shell egg industry. In light of these findings, the n-3 fatty acidenriched egg may provide an innovative food choice for the health-conscious consumer.

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