The Effect of Different Disinfectants for Controlling Salmonella Serotypes on Food Contact Surfaces: A Review

Salmonellosis is one of the most common foodborne infections worldwide. Various Salmonella enterica serotypes can cause this infection and can be transmitted through food contact surfaces. The most common way to prevent this infection is by applying disinfectant on food contact surfaces. Therefore, this research aims to summarize the effect of different disinfectants for controlling Salmonella serotypes on food contact surfaces. PRISMA guidelines were used as the method to find suitable sources for this systematic review. Relevant studies that were used are retrieved from several databases such as Science Direct, EBSCOhost, Taylor & Francis, SAGE, and Scopus. The keywords used to identify the relevant studies were “disinfectant”, “Salmonella sp.”, “food contact surface”, “food safety”, and “hygiene”. The initial search in the databases yielded 75 articles. After the screening process based on the criteria of the article, only 6 articles were used in the final systematic review. The result showed that the effect of disinfectants on foodborne pathogens, especially Salmonella serotypes, can be influenced by the composition of the disinfectant, the type of serotype, and the food contact surface material used. Therefore, in-depth consideration is needed regarding the factors that influence the effectiveness of a disinfectant, especially on food contact surfaces in the food industry.


Introduction
Microbial contamination is a serious threat to food safety.Contamination of food products or raw materials by pathogenic microorganisms can lead to diseases and outbreaks, also known as foodborne illnesses.Salmonella is one of the pathogenic bacteria that still threatens human health.Consumption of food contaminated with Salmonella can cause various symptoms or infections, such as Salmonellosis, an infection that occurs in the digestive tract.This infection continues to occur worldwide, with as many as 3.4 million cases yearly [1].In addition, cases of infection by Salmonella have been increasing recently, with 94 million cases causing 155,000 deaths worldwide each year, and 80.3 million of these cases are caused by consuming contaminated food [2].Salmonella contamination in food is a major cause of many cases of infection worldwide.There are several ways in which Salmonella contamination occurs in food, such as through direct contact of the food with food contact surfaces that have been contaminated with Salmonella [3].Examples of food contact surfaces are knives, cutting boards, and conveyor belts used to process food products.To overcome this problem, preventive measures can be taken, for example, by using active chemical agents or disinfectants on the food contact surface.The use of disinfectants is proven to slow down the growth and eliminate 1324 (2024) 012127 IOP Publishing doi:10.1088/1755-1315/1324/1/012127 2 microorganisms such as Salmonella, thereby minimizing the possibility of foodborne disease or infection [4].
Several studies have researched and studied the method of applying disinfectants to food contact surfaces.These studies have tested and examined different types of disinfectants, pathogens, and materials of food contact surfaces.Based on the research conducted by Byun [5], the effectiveness of chlorine-based disinfectants, namely sodium hypochlorite and chlorine dioxide, was tested against Salmonella enteritidis on different materials of food contact surfaces.Several food contact surface materials were studied, namely stainless steel, silicone rubber, and plastic.This research found that both chlorine-based compositions can effectively reduce the number of planktonic cells and biofilms of Salmonella enteritidis on food contact surfaces.In addition, some studies examined the effectiveness of alcohol-based disinfectants, namely ethanol with a mixture of chlorine and lactic acid, against several Salmonella serotypes on stainless steel surfaces conducted by Zhang [6].Based on the observations, it was concluded that the ethanol-based disinfectant mixture was effective in reducing the presence of Salmonella on stainless steel surfaces.Another example is the research conducted by Djebbi-Simmons [7], which evaluates and compares the effectiveness of using peroxide-based disinfectants, namely hydrogen peroxide, as well as chlorine-based disinfectants, namely sodium hypochlorite, against Salmonella Typhimurium found on food contact surfaces.This research also studied the effect of disinfectants on different food contact surface materials, namely plastic, formica laminate, and stainless steel materials.Based on this research, it can be concluded that hydrogen peroxide was more effective in decreasing the amount of Salmonella Typhimurium than sodium hypochlorite.
Through the studies that have been conducted on the effect of disinfectants against Salmonella, there are limitations to most of these studies.To our knowledge, most studies have tested and compared the effectiveness of several types of disinfectants against only one type of Salmonella serotype.Few studies evaluate and compare the efficacy of different formulations and types of disinfectants against a variety of Salmonella serotypes.Meanwhile, disinfectant composition that is ineffective on certain serotypes may be effective on other serotypes.For example, a study examined the effects of several types of disinfectants, such as sodium dichloroisocyanurate, against Salmonella Typhimurium.This study only focused on one Salmonella serotype, which is Salmonella Typhimurium.Another study by Drauch [9] focused on one of the Salmonella serotypes, Salmonella Infantis.This study tested the effectiveness of various types of disinfectants ranging from peroxygen compounds, aldehydes and quarternary ammonium (QUATS) to the combination of cresols and alkylamines.In addition, research conducted by Byun [5] only focused on one particular serotype of Salmonella, more precisely, Salmonella enteritidis.Strains of Salmonella enteritidis were tested for resistance to sodium hypochlorite and chlorine dioxide disinfectants.
The amount of research that uses various types of serotypes of Salmonella to test several compositions and types of disinfectants on food contact surfaces still needs to be increased.It can be seen through some of the literature mentioned in the previous paragraphs.Most of these studies only focus on one type of Salmonella serotype in their assessment.Therefore, a summary of the effectiveness of various types and compositions of disinfectants on different types or serotypes of Salmonella is needed to fill the limitations of the literature and research that has been done previously.Through this summary, it can be compared and seen which composition or type of disinfectant is the most effective for certain serotypes.The comparison of the effect of the composition and type of disinfectant can be seen through the log reduction number of serotypes.In addition, this summary can be used as a reference for further research in evaluating the effectiveness of different compositions that have never been studied before against certain Salmonella serotypes.Through further research on new disinfectant formulations for certain Salmonella serotypes, alternative types of disinfectants can be developed that can be used to reduce the amount of Salmonella contamination with various serotypes on food contact surfaces.Moreover, this summary also includes research on the effects of disinfectants against Salmonella with different food contact surface materials.Several studies used different food contact surface materials to examine the effect of disinfectants.This is mainly due to the different 3 effects of disinfectants on certain food contact surface materials.Different materials of food contact surfaces can have various textures, porosity, and absorbency to a certain type of disinfectant.Through this summary, the type of contact material can be observed, and comparisons can be made based on the trend of food contact surface material selection of various kinds of research.As a result, the summary of the composition, Salmonella serotypes, and food contact surface materials may be used as a reference for further research on the effects of disinfectants that have never been studied with certain serotypes, thus producing alternative disinfectants that are more efficient for certain Salmonella serotypes.Therefore, this systematic review aims to summarize the effect of different disinfectants for controlling Salmonella serotypes on food contact surfaces.

Methods
In order to summarize and analyze previous research regarding the effects of various types of disinfectants against Salmonella serotypes that are present on food contact surfaces, this systematic review follows the PRISMA protocol, which can be seen in Figure 1.The process of searching for existing research that matches the criteria will be carried out using several databases, namely, Science Direct, EBSCOhost, Taylor & Francis, SAGE, and Scopus.This search will also be assisted by using several search keywords, including "disinfectant", "Salmonella sp.", "food contact surface", "food safety", and "hygiene".The utilization of Indonesian language studies will also be considered.The reviewers will evaluate the titles, abstracts, and discussions of the studies that meet the inclusion and exclusion criteria.Through this process, several pieces of information will be extracted, including the type and composition of disinfectant, Salmonella serotype, food contact surface material, disinfectant effectiveness through log reduction parameters, and other information related to the effect of disinfectants on Salmonella with specific food contact surfaces.The data will be displayed visually to analyze the trend of existing research.The analysis can be used as a reference for further study in evaluating the effects of disinfectant compositions that have never been used on certain Salmonella serotypes.This systematic review will analyze data through published research, so no ethics approval is required.However, proper citations and references are still needed to honor the studies' authors.

Figures
Flowchart of the PRISMA protocol used in this systematic review.

Results and Discussion
The use of active chemical agents, namely disinfectants, has been proven to prevent growth and effectively kill various microorganisms [4].Foodborne pathogens are specific types of microorganisms that can be effectively reduced in number or population.However, the composition and type of different disinfectants can affect their effectiveness against pathogens.Certain pathogens or serotypes of pathogens can have varying resistance to certain types of disinfectants, including Salmonella.The following are the results of research based on disinfectant composition, food contact surface material, and specific Salmonella serotypes: Salmonella enteritidis and Salmonella typhimurium.
The particular serotype of Salmonella highlighted in this review is Salmonella enteritidis.Salmonella enteritidis is one of the most commonly identified Salmonella serotypes worldwide [8].Through this review, data and comparisons have been obtained between disinfectant compositions and their effects on Salmonella enteritidis, as can be seen in Table 1.Based on some of the research data, comparisons can be made, and conclusions can be drawn on which disinfectant composition is most effective in reducing the number of Salmonella enteritidis.A comparison of log reduction numbers can be made, and it can be concluded that the mixture of citric acid (0.03%), lactic acid (0.04%), and sodium dodecylsulfate (0.02%) is the most effective.The results of log reduction of Salmonella enteritidis with this disinfectant are declared as not detected, which can be interpreted as effective elimination of microbial load (Salmonella enteritidis has been eliminated).However, the log reduction results of this mixture of disinfectant were observed with the longest contact time, which was 4 minutes, compared to other disinfectant mixtures.This contact time factor can be further considered in its application.This disinfectant blend consists of a blend of organic acids, namely citric acid and lactic acid, with surfactant sodium dodecylsulfate.Citric acid and lactic acid are commonly used as food additives, but according to previous research, these two types of organic acids have antibacterial properties [10].This antibacterial effect is caused by the decrease in pH, which can damage the cell structure of microorganisms and create an environment that does not support the growth of microorganisms.The ability of this disinfectant to kill Salmonella enteritidis is further enhanced by adding a surfactant, sodium dodecylsulfate [11].The addition of surfactants can increase the effectiveness of disinfectants in penetrating the cell membrane of microorganisms.Increased penetration can facilitate the entry of organic acids into cells, thus helping the process of microorganism cell destruction.In addition, it was found that this disinfectant composition still has high effectiveness in the presence of organic interfering compounds, such as carbohydrates, proteins, and fats.This is an advantage of this disinfectant composition over other disinfectants that are unstable in the presence of organic compounds.In addition, combining organic acids and disinfectants can overcome the weaknesses or limitations of other disinfectants related to safety.For example, sodium hypochlorite can cause reproductive toxicity and is carcinogenic.This composition of organic acid and surfactant disinfectant is categorized as a disinfectant that is safe to use as a food disinfectant.
Salmonella typhimurium is one of the most commonly studied Salmonella serotypes.It is the most frequent serotype causing foodborne illness worldwide [12].Based on the studies, a comparison of the effects of disinfectant composition against Salmonella typhimurium was obtained, as seen in Table 2.By comparing the log reduction value, it can be seen that the composition of sodium hypochlorite with a concentration of 8.25% is the most effective against Salmonella typhimurium.The log reduction calue is observed at 4 minutes contact time.This contact time can be categorized as relatively fast and produces the most optimal log reduction value compared to other disinfectant mixtures.Sodium hypochlorite is the most commonly used chemical compound disinfectant against various pathogenic microorganisms, including Salmonella typhimurium.The high usage of sodium hypochlorite is due to its effectiveness in log reduction.The effectiveness of sodium hypochlorite against Salmonella tyhimurium is higher than other disinfectant compositions found in this review.The ability of sodium hypochlorite to control Salmonella typhimurium is due to its ability to produce compounds that can penetrate the cell wall of microorganisms.Damage to the membrane or cell wall can inactivate microorganisms, thus having a high log reduction.However, disinfectants composed of sodium hypochlorite have weaknesses or limitations.This includes a decrease in the effectiveness of sodium hypochlorite if there are organic compounds.In addition, sodium hypochlorite can produce toxic and harmful byproducts to human health [15].The use of sodium hypochlorite in high concentrations can threaten human health due to its carcinogenic properties.Through Table 2. it can be seen that two studies use disinfectants with sodium hypochlorite ingredients, where the difference between the two studies is the concentration used.The higher the concentration used, the higher the log reduction or the ability of the disinfectant to reduce or inhibit the growth of microorganisms.This comparison shows that the difference in concentration is a determining factor and can affect the effectiveness of the disinfectant.
Besides analyzing the effect of disinfectant composition on Salmonella serovar, this study also analyzed the food contact surface material used.The type of food contact surface used can be seen in Figure 2. The type or material of the food contact surface is one factor that can influence disinfectants' effectiveness against Salmonella.For example, research has shown that Salmonella biofilms formed on stainless steel surfaces are more sensitive than plastic surfaces [16].In this study, most of the material or type of food contact surface used was plastic at 37%.Most previous studies chose plastic food contact surfaces to represent food contact surface materials commonly used in residential food processing [7].In addition, previous studies show that Salmonella microorganisms can easily contaminate and form biofilms on hydrophobic surfaces, such as plastic [5].Several other types of food contact surface materials can also be contaminated by Salmonella, such as stainless steel and wood.The use and effectiveness of disinfectants on various food contact surface materials can be influenced by several factors, for example, the porosity of each material.Wood and plastic have a higher porosity than stainless steel, so these food contact surface materials can more easily absorb the disinfectant applied.This absorption could diminish the disinfectant's concentration for microbial inactivation, restricting its efficacy.Therefore, stainless steel with lower porosity may retain higher concentrations of disinfectant on their surfaces, thus increasing the effectiveness of the disinfectant used.Another factor is the texture of the food contact surface material used.Rough food contact surfaces can reduce contact time with pathogens.In contrast to rough surfaces, smooth food contact surfaces can increase the effectiveness of disinfectants.
The application of the right type and composition of disinfectant for food contact surfaces is crucial for the food industry.Especially to overcome contamination and diseases caused by Salmonella serotypes, which still threaten food safety.By using disinfectants, the food industry can improve food safety by preventing foodborne illness due to contamination originating from the food contact surface of products processing.In accordance with food safety, the food industry can also increase consumer trust regarding the safety of the industry's food products by using the right disinfectant.Safety assurance of food products is a form of commitment from the food industry to consumers to provide products that are ensured of safety.Apart from being closely related to the food industry, the use of the right disinfectant mixture on food contact surfaces is also in line with the Sustainable Development Goals (SDGs).A major SDG closely related to this paper is SDG 2 (Zero Hunger).Utilizing the right disinfectant mixture on food contact surfaces can reduce the risk of foodborne illness, especially due to Salmonella contamination.Food safety will be improved by reducing the risk of foodborne illness.With the increase in food safety, it will result in more secure and safe food supplies, thus reducing hunger.In addition to SDG 2, the results of this paper also contribute to SDG 3 (Good Health and Well-being) in the aspect of public health.Public health can be significantly improved by reducing the risk of Salmonella contamination by using the right disinfectant mixture on food contact surfaces.
Based on this review, more studies use various disinfectant compositions against Salmonella enteritidis.In contrast to research on Salmonella typhimurium, which still uses the same type of disinfectant.In addition, most studies use plastic as a food contact surface material.Unfortunately, materials such as wood and others are still poorly studied against the effects of certain disinfectants.By seeing the results and discussion in this systematic review, readers can find the most effective disinfectant composition against different Salmonella serotypes.Therefore, the food industry can use the most effective composition for sanitizing food contact surfaces.Further research can also be conducted to examine alternative compositions for each Salmonella serotype and other food contact surfaces.

Conclusions
In conclusion, the effect of disinfectants on Salmonella serotypes can be influenced by various factors.Using a mixture of organic acids and surfactants showed the highest effectiveness on Salmonella enteritidis.On the other hand, the application of disinfectants made from sodium hypochlorite had the highest effectiveness on Salmonella typhimurium.Moreover, the different materials of the food contact surfaces studied can also influence the effectiveness of the disinfectants, such as porosity and texture.Most studies use plastic materials, while research with wood and other materials is minimal.Therefore, the effect of disinfectants on foodborne pathogens, especially Salmonella serotypes can be influenced by the composition of the disinfectant, the type of serotype, and the food contact surface material used.

Figure 2 .
Figure 2. Types of Food Contact Surface.The type or material of the food contact surface is one factor that can influence disinfectants' effectiveness against Salmonella.For example, research has shown that Salmonella biofilms formed on stainless steel surfaces are more sensitive than plastic surfaces[16].In this study, most of the material or type of food contact surface used was plastic at 37%.Most previous studies chose plastic food contact surfaces to represent food contact surface materials commonly used in residential food processing[7].In addition, previous studies show that Salmonella microorganisms can easily

Table 1 .
The Effect of Various Disinfectant Compositions Against Salmonella enteritidis.

Table 2 .
The Effect of Various Disinfectant Compositions Against Salmonella typhimurium.