Challenges of Cooking Oils in Fast-Food Restaurants of Iran: Views of Consumers

Abstract

The purpose of this study was to explore Tehranian women’s perceptions about the quality and safety of cooking oils in fast-food restaurants and their behavior toward these challenges in 2018. A qualitative study with eight focus group discussions was conducted among 82 women using content analysis and constant comparison methods. Three categories emerged with 4 themes and 27 subthemes: (a) high usage of frying foods, (b) fast-food restaurants, and (c) building community trust. The majority of women had desirable knowledge about the disadvantages of cooking oils used in fast-food restaurants. The participants mentioned that the most challenging problem of fast-food restaurants was the reused cooking oils. Therefore, the health policy-makers should consider to develop a guideline for improving the cooking oils’ quality and safety in fast-food restaurants. It is recommended that the restaurant inspection system should be examined to identify appropriate ways of ensuring food safety.

Keywords

cooking oil fast-food restaurants qualitative research challenges

Introduction

Nowadays, fried or deep fried foods have become one of the major items of Iranian diet.¹ In addition, a great portion of edible oils in Iran are imported from other countries. However, due to recent sanctions and economic issues that followed, safe edible oils are expensive and rare.

Over the past decades, fast-food consumption has increased worldwide because of the lack of time for the preparation of food, which is reflected in the increase of eating out consumption.^2,3 The first fast-food restaurants were opened in 1961 in Tehran, Iran. It is estimated that more than 20,000 fast-food establishments are located in Iran, predominately in Tehran. There are many differences in terms of quality and efficiency between the global fast-food chains and those found in Iran.⁴ Furthermore, they are convenient, fairly inexpensive, and liked by people of various age groups.⁵ Fast food is a growing component of the Iranian diet such that the frequency of its use has increased drastically.^6,7 Although fast foods may meet quickly one’s dietary needs, the high polar compounds, produced after repeated heating of these foods, can result in harmful health effects.^8,9 In addition, cooking oils, used for frying in fast-food restaurants, are reused several times and usually kept in unsuitable environments exposed to air, heat, and light.¹

Women are the mainstays of their family and food keeper in Iranian culture and their health is extremely important; therefore, understanding the level of their knowledge, attitude, and practice plays an important role in the health of the community and the next generations.^10,11

Traditionally, Iranians like to have home-cooked meals. However, due to globalization and the influence of western culture as well as the increasing participation of women in economic activities that reduces the time allowed for preparing homemade food, there is a slight shift in food consumption patterns among Iranian urban families in recent years, thus home-cooked foods are losing out.⁸ This behavioral change has occurred because more people are eating out and are enjoying a wide variety of international foods.

Some studies have shown that poor diet is one of the main reasons for the increase of cardiovascular diseases (CVDs) and that the excessive consumption of fast food is responsible for the poor quality of diet.^12,13

Limited studies have been conducted regarding the challenges of cooking oils in fast-food restaurants in Iran.^14,15 This qualitative study was done in 2018, Tehran, Iran, in the framework of “Assessment of the quality and safety of frying oils (qualitative and combination features) in fast-food restaurants in Tehran and the design and development of oil optimization policies.” This is the first study to explore the challenges of cooking oils in fast-food restaurants in Iran.

Methods

The underlying theoretical approach to this qualitative research was grounded theory, as this enables exploration of social processes, interactions, and contextual factors affecting the individuals’ opinions about the cooking oil safety. Focus group discussions (FGDs) elicit data from a group of participants who can hear each other’s responses and provide additional comments that they might not have made individually. The researchers who conduct FGDs recognize the participants’ interactions, which stimulate the identification and sharing of various perspectives on the same topic.¹⁶ The use of FGDs was chosen as a well-established method, as it explicitly uses group interaction for collecting rich data. In addition to responding to the researcher, the participants respond to each other thus producing new ideas, questions, and priorities. The views and perspectives can be changed or developed during the discussions, leading to the generation of critical comments and potential solutions to the problems.¹⁷

Design and Sample

In this qualitative study, eight FGDs were convened using content analysis method in six health centers from five districts (North, East, West, South, and Center) of Tehran, Iran, in 2018. The districts were classified as being high, moderate, and low socioeconomic status based on a report by the Ministry of Economic and Financial Affairs.¹⁸ The use of qualitative techniques as FGD has some methodological advantages because they employ open-ended questions and probe a range of views, knowledge, attitude, and practices of particular groups about specific issues, which can then be identified.¹⁷ The FGDs were held until reaching saturation (which means no new idea or comment) in each center.¹⁹ A pilot FGD was conducted in one of the health centers with 10 women who were not included in the main study. The purpose was to match the performance of all team members and to check the questions’ intelligibility.

Participants

The study participants included those women who used to go fast-food restaurants. They were invited by the health centers’ staff through the phone call and informed about the purpose of the study to participate in the study on a specific date based on their willingness. In a continuous procedure, 96 women were contacted; 82 of them accepted to cooperate and 14 women were excluded as they were not available and said that they never go to fast-food restaurants. Each FGD included 7 to 10 participants and lasted about 60 minutes.

Data Collection

At the beginning of each session, the moderator introduced the research team members and explained the purpose of the study. The participants were encouraged to state their opinions freely and were informed that wrong or right answers were expected by the researchers. They were then asked to introduce themselves as a means of getting acquainted with each other. The participants were seated together with the moderator in a semicircle in the center to allow eye contact and the free flow of discussion. Then they were informed that their voices would be recorded by a digital recorder. They were also assured that their names and wordings would not be revealed to anyone other than the research team.

The moderator’s guide was designed based on the research objectives, which consisted of a series of open-ended questions developed by the research team and reviewed by an academic review panel to allow the respondents to explain their own opinions and experiences.^16,20 The questions explored the experts’ attitudes about the important challenges regarding the cooking oils used in Iranian fast-food restaurants (Table 1).

Table 1.

Focus Group Discussion Moderator’s Guide.

Questions

1) What is your idea about the disadvantages of high usage of frying foods? - Diseases and complications

2) What are your selection criteria to choose fast-food restaurants? - Selection criteria - What are your reasons for going to fast-food restaurants?3) What are the problems of cooking oils in fast-food restaurants?4) In your opinion, what should policy makers do to build community trust? - Approaches

Each team consisted of one moderator, one observer, and two note-takers. The moderator was a flexible, open-minded, and active listener and was able to establish a report with the participants and encourage them to talk comfortably. The moderator also provided a short orientation as an ice breaker. The note-takers were swift and accurate in writing. The observer watched what happened but had no active part in the discussions.¹⁷

Triangulation has been viewed as a qualitative research strategy to test the validity data through the convergence of information from different sources. This method involves the use of multiple methods of data collection about the same phenomenon. Data source triangulation involves the collection of data from different types of people, including individuals, groups, families, and communities. Triangulation was done by the collection of data through interview by stockholders²¹ and FGD with women with different socioeconomic statuses residing in different districts of Tehran to gain multiple perspectives and validation of data. To ensure data accuracy and consistency in the interpretations during the course of data analysis, the research team kept decision trails to document the decisions made over the course of the study. The results were also checked with some of the participants who met the inclusion criteria but did not participate in the research; they confirmed the fitness of the results. To confirm dependability, four faculty members conducted a second review. The results were further checked with some of the main key informants; they confirmed the fitness of the results too. All the details including procedures, actions, and decisions were documented for audit purposes. During the discussions, the views and perspectives were changed or developed that led to the generation of critical comments and potential solutions to the problems.²²

Data Analysis

After each session, the notes were organized based on the focus group questions and probes, and emotional such as expressions, laughter, and sighs were noted. The record of each focus group was transcribed verbatim and compared with the notes to fix potential discrepancies. The final transcripts were read repeatedly to achieve immersion and obtain a sense of the whole as one would read a novel.

All the data relevant to each category were identified and examined using the constant comparison method.¹⁶ Then each item was checked or compared with the rest of the data to establish analytical categories by writing, reading, and rereading the developed codes and themes as well as discussing the transcripts at the team meetings. The data were read word by word by the team members independently. Subsequently, the codes were derived by highlighting the exact words from the text to capture key thoughts or concepts. These often came directly from the phrases frequently appearing in the text, which then became the initial coding scheme. Next, the codes were sorted into categories based on how different codes were related and linked. The emerged categories were used to organize and group the codes into meaningful themes. The interrater reliability was calculated using percent agreement (interrater reliability r = .87). This agreement showed that the coding list was reliable. The disagreements were discussed, and new or adjusted coding categories were imported to all transcripts.²³

This study was approved by the Ethical Committee of National Nutrition and Food Technology Research Institute, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran (No. 190). The subjects were informed that their participation in the study was voluntary, and they had the right to withdraw from the study at any time. Written informed consent was obtained from all participants. They did not receive monetary compensation for their participation.

Results and Discussion

The results showed that the majority of the interviewed women (50%) were in the age range of 40 to 60 years; 94% of them were housewives, and the majority of them held a diploma and higher degrees (58%) (Figure 1).

Figure 1.

Characteristics of the study participants: (a) age-group, (b) educational level, and (c) area.

According to the FGD results, three categories emerged consisting of 4 themes with 27 subthemes based on the perspectives of the participants (Table 2).

Table 2.

Open Coding Results (the Most Important Concepts Extracted According to Priority).

Category	Theme	Subtheme
High usage of frying foods	Diseases and complications	• Cardiovascular diseases• High blood fats (cholesterol)• High blood pressure• Cancer• Obesity• Fatty liver• Digestive problems
Fast-food restaurantsBuilding community trust	Selection criteriaChallenges of cooking oilsApproaches	• Hygiene level• Previous experiences• Fine cuisine, fresh food, quality of cooking and decoration of foods• Advertising and brand image of the restaurant• Restaurants’ interior design• Variety of foods in menu• Cost• Service speed• Multiple use of cooking oils change the foods’ color and makes bitterness of food• No plan for collecting used cooking oils• Presence of a food quality expert in fast-food restaurants• Increasing the knowledge of community about food safety via media• The kitchen should be visible or shown online on the monitor• Encouraging producers to increase production of safe cooking oils and also reducing food fraud• Legislation requiring nutrition labeling in fast-food centers• Rating the restaurants based on the quality of foods prepared• Controlling the personal hygiene and sanitary environment• Controlling the quality and freshness of food• Controlling the advertisements and media slogans regarding fast foods• Governmental inspection (by food quality control assurance experts)

High Usage of Frying Foods

Diseases and complications

All participants in this study mentioned that oils and fats have significant impact on health. The majority of them said that excessive use of cooking oils can cause CVDs, high blood fat (cholesterol), high blood pressure, cancer, obesity, fatty liver diseases, and digestive problems.

Epidemiological and clinical studies have indicated that fast-food consumption may be associated with a risk for CVDs. These studies report that consumers of fast foods have higher intakes of energy, fat, saturated fatty acid, sodium, and carbonated soft drinks with fewer intakes of fruits, vegetables, milk, and vitamins C and A.²⁴ The results of a study on Iranian adults indicated that the increasing rate of fast-food consumption was associated with poor dietary intake, which can lead to CVD risk factors.⁵

Although the majority of participants in this study had desirable knowledge about the disadvantages of high usage of frying foods in fast-food restaurants, they still prefer to go to fast-food restaurants for changing their mood, having fun, and for food variety. Therefore, it is better that people pay more attention to their food habits by reducing fast-food consumption. At the same time, owners of restaurants should enhance the nutritional quality of their foods by using fresh oil and avoid using the used oils, as well as adding more fibers (e.g., vegetables, fruits, legumes, whole bread) to their dishes in order to help to reduce CVD risk factors.²⁰ Nowadays, fast-food restaurants have become an inevitable part of life, so improving the nutritional quality of fast foods can lead to increasing the health of the community and reducing the emergence of noncommunicable diseases.

Fast-food restaurants

The majority of the participants are used to go to fast-food restaurants, and more than half of them mentioned that they go to fast-food restaurants at least once per month.

Fast-food restaurants’ selection criteriaMost of the participants stated that they choose fast-food restaurants due to their previous experiences, hygiene level, fine cuisine, fresh food, quality of cooking, advertising, brand image of the restaurant, decoration of food, and so on. Unexpectedly, only a few of them were concerned about the cost of the foods and speed of the service. A similar trend is also observed in other studies. Recently, an increasing number of individuals are interested in eating out and visiting fast-food restaurants.²⁵ In 2018, a study in India showed that hygiene level was the third criterion for the participants to choose fast-food restaurants. Service speed was the last criterion among the Iranian participants, whereas it was the first choice in the Indian consumers.²⁶The results of a study in New York showed that approximately 35% of adolescents ate fast food six or more times per week, and 72% of them reported that taste was the most important factor in their meal selection.²⁷The majority of women preferred home-cooked foods due to their higher quality, hygiene, safe ingredients such as cooking oil, and fewer calories, and affordable price. Iranians eat fast food not only for the cuisine but also as a leisure activity and a means of socializing. The findings of this study showed that in the view of participants, the factors promoting the consumption of fast foods appear to be stronger than the inhibiting factors. It is also important to note that they tended to use different criteria in choosing restaurants.²⁸

Challenges of cooking oilsThe majority of participants mentioned the multiple reuse of cooking oils in fast-food restaurants as their major concern with the fast foods. In addition, they said that there is no specific policy for collecting and recycling of used cooking oils; however, the municipality, for instant, can provide a system for recycling of discarded cooking oils to make local energy. Biodiesel is advised for use as an alternative fuel for conventional petroleum-based diesel chiefly because it is a renewable and domestic source of energy with an environmentally friendly emission profile and is readily biodegradable.^29,30The majority of the participants recommended the following approaches to reduce the consumption of reused oils: purchasing foods prepared with different methods of cooking (boiled and grilled foods) and consuming vegetables along with the food.

Building Community Trust

According to the findings of this study, the majority of the women stated that they had no trust in the safety of the foods prepared in fast-food restaurants and recommended the following approaches to solve this issue: (a) presence of a food quality controller in fast-food restaurants, (b) increasing the knowledge of community about food safety via social media channels, (c) the kitchen should be visible or shown online on the monitor, (d) encouraging producers to increase the production of safe cooking oils and also reducing food fraud, (e) legislation requiring nutrition labeling in fast-food preparing centers, (f) personal hygiene and sanitary environment, (g) controlling the quality and freshness of foods, (h) controlling advertisement of fast foods and media slogans, and (i) governmental inspection of fast-food restaurants (by food quality control assurance experts). Furthermore, it is better that restaurants be rated according to their food quality. They also said that it is the social responsibility of restaurants to inform the clients regarding the nutritional contents of the food items (calories and nutrients). The research results showed that the participants had desirable knowledge about cooking oils and the related problems; however, they could not change their behavior because of media intervention and lifestyle issues. Hence, legislations are needed to mandate the restaurant industry to adopt a more caring role and social health responsibility and not just serving as a vehicle satisfying consumers’ daily food needs and wants.³¹ Therefore, the government force to follow and implement nutrition labeling policy of fast-food restaurants in order to increase public knowledge about healthy food intake and improve their dietary patterns. Consumer trust is one of the great factors in food safety that can improve the effectiveness of public policy and allow the development of the best practice in risk communication.³² Building consumer trust provides richer and more credible data for health policy-makers in the field of controlling the intake of nutritional risk factors of the NCDs.

As Iran is undergoing an epidemiological and nutritional transition, major changes have occurred in Iranian people’s lifestyle and food consumption patterns.³³ Unlike some restrictions on advertisement of unhealthy foods in Iran, yet these products are advertised openly on Iranian TV. Such advertisements can lead to more positive taste experiences when these foods are consumed; this, in turn, can neutralize the effect of healthy messages and have a long-term negative influence on peoples’ lifestyle.³⁴ Media advertising encourages using more fast-food products in Iran. Thus, policy-makers need to set a scientific commitment for modifying and controlling these advertisements in order to reach a desirable healthy food consumption pattern. Increasing the knowledge of the community would be effective on their food choice and improving the quality and safety of cooking oils.³⁵ These products can also enter the competitive market. Further studies can focus on the views of adolescents, health experts, health policy-makers, and other stakeholders.

Conclusion

The majority of women participating in the present work had desirable knowledge about the disadvantages of cooking oils in fast-food restaurants, but they preferred to choose fast-food restaurants for the reasons such as changing their mood, enjoyment, and the variety of food. On the other hand, most of them said that fast-food restaurants are not reliable and trustable, and they were and still are worried about the safety of fast-food products, especially the cooking oils used for preparing fast foods in restaurants. They further mentioned that the problem of fast-food restaurants was the long and multiple use of cooking oils. They also believed that there is not any policy for collecting and recycling of discarded cooking oils. Hence, there is a definite need for designing a system for this challenge. The evidence from this study suggests that providing interventional programs and establishing policies in the abovementioned areas are necessary in order to modify the use and consumption pattern of cooking oils in fast-food restaurants. The results further suggest the need for presence of a food quality control expert in fast-food restaurants. Fast-food providers need to focus on consumers’ preference to building trust. Health policy-makers should consider developing a guideline for improving the quality and safety of cooking oils used in fast-food restaurants. Finally, it is recommended that the restaurant inspection system should be examined to identify ways to ensure food safety.

Limitations

The main limitation of this study is that it was conducted on women admitted to health-care centers; therefore, the results are only applicable to this group of women. Moreover, the socioeconomic status of fast-food consumers was not strictly determined. Men and other geographical areas should be included in future studies via population-based design.

Footnotes

Acknowledgments

All the participating women are greatly appreciated for their valuable help in conducting this study. The authors would also like to thank Ms. Julian Spokes and Susan K Raatz as native technical editors.

Authors’ Contributions

The funding agency did not contribute to the design or conduct of the study as well as the collection, management, analysis, or interpretation of the data, preparation, review, approval of the manuscript, or decision to submit the manuscript for publication. FE designed the research and provided the overall guidance. FE drafted the manuscript. All authors checked and interpreted the results, revised the manuscript for important intellectual content, and read and approved the final manuscript. FE has primary responsibility for the final content.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Ethical Considerations

Ethical issues (including plagiarism, informed consent, misconduct, data fabrication and falsification, double publication and submission, redundancy) have been completely observed by the authors.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The authors would like to appreciate the Research Council of National Nutrition and Food Technology Research Institute, Faculty of Nutrition Science and Food Technology, Shahid Beheshti University of Medical Sciences for financial support.

Author Biographies

Fatemeh Mohammadi-Nasrabadi is an associate professor (in Research) in Nutrition (Minor: Economics) and head of Food and Nutrition Policy and Planning Research Group, National Nutrition and Food Technology Research Institute (NNFTRI). My research projects are predominantly on food security modeling, food and nutrition policy research, and evaluation of cash transfer programs.

Aziz Zargaraan is an assistant professor (in Research) in Food Technology (Minor: Edible oil) and an academic member of food and nutrition policy and planning research department, in national nutrition and food technology research institute (NNFTRI), in Tehran, Iran. Majority of his research projects are predominantly on edible oil industry.

Yeganeh Salmani is BS in Food science and Technology at the National Nutrition and Food Technology Research Institute (NNFTRI) in Tehran, Iran. Her research interests are food policy, food safety and food security.

Fatemeh Esfarjani is an academic member of food and nutrition policy and planning research department, in national nutrition and food technology research institute (NNFTRI), in Tehran, Iran. She has years of experience in research, evaluation, teaching and administration both in hospital and education institutions. Her field of interest is food safety and food security, she published 23 papers in academic journals and more than 124 abstract presentations in congresses. She was involved in many projects as principal in these area.

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