Effects of Çemen pastes prepared in different formulations on physicochemical, microbiological, and textural properties of beef hamburger patties during refrigerated storage

Abstract This study aimed to investigate the effects of çemen pastes prepared in different formulations on physicochemical, microbiological, and textural properties of hamburgers during refrigerated storage (4°C; 60 d). Çemen pastes were produced by using different combination doses of fenugreek seed flour, sweet red pepper, and garlic powder. As a result of çemen paste usage in hamburgers, cooking losses and dimensional shrinkage decreased, whereas moisture and fat retention ratios increased (p < .05). The hardness, gumminess, and chewiness values of hamburgers containing çemen paste were generally lower than those of control (p < .05). Çemen paste addition to hamburgers generally did not cause a difference in terms of microbial growth and moisture, fat and ash contents. Protein contents of hamburgers containing çemen paste or breadcrumbs were generally higher than that of control (p < .05). Çemen paste usage in hamburgers generally decreased the L* values and increased the b* values (p < .05). In general, addition of 3.5% or higher doses of both sweet red pepper and garlic powder caused higher a* values in hamburger patties (p < .05). Lower oxidation levels were generally observed in hamburgers containing 3% or lower doses of fenugreek seed flour and 4.5% of garlic powder in çemen paste (p < .05). It was concluded that çemen paste usage in hamburger patty processing has the potential to improve the quality characteristics and delay oxidative changes.


| Hamburger production
Hamburgers were produced, according to the procedure described by Kılıç et al. (2018).Hamburgers were produced in triplicate on separate production days.First, the meat was chopped by passing through 9.5 and 3.2 mm mincer chucks of a meat grinder (PKM-22 Meat Grinder, Arı Machine, İstanbul), respectively.
The beef back fat was minced using a meat grinder with 3.2 mm mincer chuck.
Hamburger patties were prepared, according to the formulations (%) for the production of hamburgers and group codes presented in Table 1.Differences in the hamburger formulation were sourced from applied ingredient doses.Çemen paste was prepared with a ratio of 1:1 mixture of water and çemen additives (fenugreek seed flour [FSF], garlic powder [GP], and sweet red pepper [SRP]).Hamburgers were shaped using a hamburger mold with a diameter of 10 cm and a thickness of 1 cm (approximately 100 g each).Hamburgers were cooked in a conventional oven (Kumtel, Türkiye) set at 200°C until the core temperature of 72°C.Hamburgers were cooled at ambient temperature for 20 min.The styrofoam trays (Alhas packaging, Türkiye) containing cooked hamburgers were placed into polyamide/polyethylene (PA/PE; 80 μm) pochettes with an O 2 permeability of 12 cm 3 / (m 2 24h 1atm) and a water vapor permeability of 0.038 g mm/ (h kPa m 2 ).The pochettes were sealed by applying a vacuum of −0.85 bar for 10 s using a vacuum machine (Ramon VP280, Spain).The packaged hamburgers were stored at 4°C for 60 days.
Proximate composition (moisture, fat, protein, and ash) and TA B L E 1 The formulations (%) for the production of hamburgers and group codes.Sweet red pepper 0.25 0.25 2.5 2.5 2.5 3 3 3 3.5 3.5 3.5 Garlic powder 0.75 0.75 2.5 3.5 4.5 2.5 3.5 4.5 2.5 3.5 4.5 cooking characteristics (cooking loss, moisture and fat retention, dimensional shrinkage, decrease in patties diameter, and increase in patties thickness) were determined once for each of the three replications on production day, and the results of proximate composition and cooking characteristics are expressed as grams per one hundred grams (g/100 g) of hamburger in wet basis (%).pH, thiobarbituric acid reactive substances (TBARS), lipid hydroperoxide (LPO), and color values were determined on days 0, 15, 30, and 60 during storage.Texture profile, water activity (a w ), and microbiological analyses were carried out on days 0, 30, and 60 during storage.Moreover, microbiological analyses were performed on raw hamburgers once.

| Cooking characteristics and proximate composition
The percentage of cooking loss, cooking yield, moisture and fat retention were calculated according to the following equations expressed by López-Vargas et al. (2014).

Moisture retention (%)
= percent cooking yield × percent moisture in cooked hamburgers 100 The diameters and thicknesses of raw and cooked hamburgers were measured from four different points using a digital caliper.
The percentage of shrinkage, increase in thickness, and decrease in diameter were calculated according to the following equations described by Das et al. (2007).

| Texture profile analysis (TPA)
Texture profile analysis (TPA) tests in hamburgers were performed using a CT3 Texture Analyzer (Brookfield Engineering Labs., Inc., USA).Hardness (N), adhesiveness (mJ), gumminess (N), cohesiveness, springiness, chewiness, and resilience values were determined with TPA (Caine et al., 2003).Hamburger samples were taken from the refrigerator and held at ambient temperature for 1 h.Hamburger samples were cut as 1 × 4 × 4 cm in size, placed on the texture analyzer's base, and subjected to texture profile analysis at three points for each of the three replications.Test conditions were: aluminum rectangular probe (9 mm × 35 mm × 0.05 mm), test speed 1 mm/s, pretest speed 1 mm/s, posttest speed 3 mm/s, compression 70%, and 25 kg load cell.
Microbiological analysis results were given as log colony-forming units per gram ((CFU)/g) of hamburgers.triplicate for each of the three replications.The data obtained from analyses were subjected to one-way analysis of variance (ANOVA).

| Design and statistical analysis
Significant differences between the means were evaluated by using Duncan's multiple range test.Moreover, the means obtained from proximate composition analyses of raw and cooked hamburgers were also separated, according to the two-sample t-test method.
Differences among means were tested at 5% significance level.The results were given as mean ± standard deviation (SD).

| Cooking characteristics and proximate composition
Results (Table 2) demonstrated that the highest cooking loss (CL) value was determined in control (p < .05).Moreover, CL of hamburgers containing çemen paste did not significantly differ from breadcrumbs (BC) except CP1 which had lower CL than BC.Similarly, previous studies indicated that CL of meat products, such as beef hamburgers, beef meatballs, and spent hen meat patties, decreased due to BC or FSF usage (Ergezer et al., 2014;Hegazy, 2011;Qureshi et al., 2018).BC or FSF provides an excellent barrier against mass transfer from food matrix due to their adhesive properties (Hegazy, 2011;Putri et al., 2022).CP1 had a lower CL compared to control, BC, CP3, CP4, CP5, CP6, and CP7 (p < .05).
Control had a lower moisture retention ratio compared to other groups, whereas there were no differences in terms of moisture retention ratios between BC and groups containing çemen paste.
Likewise, Ergezer et al. (2014) noted that control had lower moisture retention ratio compared to the group containing BC (10%).
Considering fat retention ratios, the highest fat retention ratio was determined in CP5 (p < .05).Conversely, the lowest fat retention ratio was obtained in control (p < .05).Moreover, CP1, CP2, and CP7 had higher fat retention ratios compared to BC (p < .05).Hegazy (2011) observed that hamburgers extended with 9 and 12% FSF had higher moisture and fat retention ratios.Additionally, Ergezer et al. (2014) revealed that the highest fat retention percentages were observed in the samples extended with 10% BC or 20% potato puree.
Control showed a greater decrease in hamburger diameter (p < 05) as a result of cooking compared to BC and groups with çemen paste except CP2, CP6, and CP8 which were quite similar to control.The reduction in diameter is related to the loss of water and fat depending on the denaturation of meat proteins (López-Vargas et al., 2014).BC or çemen paste addition could have contributed to the reduction of this phenomenon through their water-and fat-binding capacities.CP2, CP6, and CP8 had a higher decrease in hamburger diameter compared to CP1 (p < .05).Additionally, decreases in hamburger diameter were similar between BC and groups with çemen paste.Dinçer et al. (2018) reported that decrease in diameter of meatballs containing retrograded flour was lower, compared to those containing BC.
Increase in patty thickness values were lower (p < .05) in BC, CP3, CP4, CP7, CP8 and CP9 compared to control.This could be TA B L E 2 Effects of breadcrumbs or çemen paste addition on the cooking characteristics (%) of hamburgers.due to the binding properties of BC or çemen paste, which held both water and fat together and resisted dimensional changes of product.Das et al. (2007) demonstrated that soy paste addition reduced the ratio of increase in goat meat patty thickness.Furthermore, CP2 had a higher (p < .05)increased ratio in hamburger thickness compared to others (except CP5).
The shrinkage ratio of control was higher (p < .05)than those of other groups (except CP2 and CP6).Additionally, BC had a shrinkage ratio similar to those of groups with çemen paste (except CP2 and CP6).Similarly, Hegazy (2011) reported lower shrinkage ratios in hamburgers containing FSF at 9% and 12% levels with reference to that of control.Alqahtan et al. (2022) noted that the replacement of BC with bisr date powder at 50%, 75%, and 100% increased the dimensional shrinkage.Furthermore, Das et al. (2007) stated that soy paste addition in patties did not affect the dimensional shrinkage.
Proximate compositions of raw and cooked hamburgers are given in Table 3.Control had higher (p < .05)moisture contents than those of CP4 and CP8, whereas there were no differences between control and other groups.Other researchers reported that similar moisture changes were obtained as a result of using BC or FSF in beef patty (Ergezer et al., 2014;Hegazy, 2011).The cooking process did not influence moisture content in all groups (except CP8).Pinero et al. (2008) found a similar result for moisture content changes in beef patties due to the cooking process.In cooked hamburgers, CP5 had a lower moisture content compared to control, CP7, and CP8 (p < .05).In raw hamburgers, CP5 and CP7 had lower fat contents compared to con-

| pH, color, water activity, and texture profile analysis
As shown in  Martínez, Cilla, et al. (2006a) reported that SRP usage in pork sausages did not cause pH differences.Additionally, previous studies showed that the addition of garlic powder or black garlic powder into fresh pork loin or spent duck meat nuggets resulted in lower pH values (Park et al., 2008;Lishianawati et al., 2022).Even though garlic powder is generally considered as an alkaline ingredient, the acidity of garlic powder has been speculated to show variation.For instance, Hwang and Kim (2022) reported that pH of the commercial garlic powders ranged from 5.78 to 6.85.On the other hand, Sun et al. (2000) noted that fresh garlic addition to Chinese sausages had an increasing effect on pH, whereas the added garlic powder The major factor in pH decrease in vacuum-packed meat products is the growth of lactic acid bacteria resulting in lactic acid production (Fernández-López et al., 2008).In the present study, control had a lower pH than those of CP1, CP2, CP3, and CP5, and a higher pH than those of BC, CP6, CP7, and CP9 on day 30 (p < .05).On day 60, the lowest pH value was obtained in BC, whereas control had the highest pH value (p < .05).
Color results ( hamburgers increased b* values (p < .05).Similar results were reported for increase in b* values in sausages containing SRP (Martínez, Cilla, et al., 2006a) and meatballs containing fresh or aged garlic (Kim et al., 2019).Results also indicated that CP8 and CP9 groups had There was no a w difference among groups (data not shown) on day 0. Dinçer et al. (2018) reported that there was no a w difference among meatballs containing bread, rusk, or retrograded flour.On day 30, CP2, CP5, and CP6 had lower a w compared to CP7 (p < .05).
Moreover, control had the highest a w on day 60 (p < .05). a w values did not differ between BC and groups containing çemen paste (except CP7 on day 60) in all storage days.a w values of groups (except control and CP5) decreased on day 60 compared to production day (p < .05).
The TPA results (data not shown) revealed that the highest hardness (N), resilience, cohesiveness, gumminess (N), and chewiness values were determined in control (p < .05).These results showed that the addition of çemen paste into hamburger patty formulation resulted in a decrease in textural parameters (p < .05).Likewise, previous studies indicated that the addition of various ingredients, such as soy paste, flaxseed flour, or tomato paste into goat or beef patties, decreased the hardness, springiness, cohesiveness, chewiness, and gumminess values (Das et al., 2007;Valenzuela-Melendres et al., 2018).Additionally, Bastos et al. (2014) found that hamburgers containing various types of flour presented lower hardness.As these flours or pastes are fiber sources, they contribute to hygroscopicity and thus provide the characteristic juiciness of the final product.There were no significant differences between control and BC groups in terms of adhesiveness (N sec) and springiness.BC had generally higher (p < .05)hardness (N), gumminess (N), and chewiness values compared to groups containing çemen paste (except CP4, CP6, and CP7).Resilience values of groups containing çemen paste were lower than those of BC (p < .05).
Conversely, there were no differences in cohesiveness values between BC and groups containing çemen paste.Alqahtan et al. (2022) reported that hamburgers containing BC had higher hardness, gumminess, and chewiness values compared to hamburgers containing bisr date powder.No significant differences were generally obtained among groups with çemen paste in terms of adhesiveness (N sec), resilience, cohesiveness, gumminess (N), and chewiness.CP2 had generally lower hardness

| Thiobarbituric acid reactive (TBARS) substances and lipid hydroperoxide
According to thiobarbituric acid reactive (TBARS) results (Table 6), control and BC displayed similar TBARS levels on day 0 to groups containing çemen paste (except CP1, CP4, and CP7).On days 0 and 15, CP1, CP4, and CP7 displayed generally higher TBARS levels than those of control and BC (p < .05).TBARS levels were similar between control and other groups (except CP1, CP7, and CP9) on day 15.Moreover, TBARS levels were lower in CP9 and higher in CP1 and CP7 compared to control on day 15 (p < .05).Whereas TBARS levels of control were similar to those of CP1, CP2, CP4, CP7, and CP8 on day 30 and as regards CP1 and CP7 on day 60, TBARS levels of control were higher than those of others (p < .05).Hegazy ( 2011) revealed that hamburgers containing 3% FSF had higher TBA content compared to control, whereas an increase of FSF in hamburgers from 6% to 12% resulted in a high TBA reduction.Pandey and Awasthi (2015) reported that FSF has antioxidant activity due to its high content of flavonoids and phenolic compounds.On days 30 and 60, CP9 (2% FSF, 3.5% SRP, and 4.5% GP) had generally lower TBARS compared to those of other groups (except BC and CP6 on day 30, and CP6 on day 60).Consistent with these results, previous studies demonstrated that SRP and fresh or aged garlic were remarkably effective in inhibiting lipid oxidation in beef and pork patties (Kim et al., 2019;Sánchez-Escalante et al., 2003).
Study results revealed a gradual increase in TBARS in all groups during storage (p < .05).Likewise, previous studies revealed that TBA values of patties containing BC or çemen paste increased during the processing or storage period (Ergezer et al., 2014;Kök & Çiçek, 2022).
The LPO results (

| Microbiological analysis results
Microbiological analysis results of raw and cooked hamburgers are shown in Table 7.The groups containing çemen paste (except CP9) in raw hamburgers displayed TMAB counts similar to control and BC.
Likewise, previous studies showed that there were no significant differences in total bacterial counts between control and the patties containing SRP or GP (Mancini et al., 2020;Shim & Chin, 2013).
Regarding total coliforms in raw hamburgers, control had a higher (p < .05)coliform count compared to BC and CP6.Conversely, higher coliform counts were determined in CP1, CP3, and CP4 compared to control (p < .05).According to yeast-mold counts in raw hamburgers, control, BC, CP1, and CP2 had lower yeast-mold counts compared to other groups (p < .05).Previous studies showed that initial TMAB, coliform, and yeast-mold counts of raw hamburgers or meatballs ranged from 6.05 to 7.48 log CFU/g, 3.77 to 3.94 log CFU/g, and 3.09 to 4.33 log CFU/g, respectively (Barbosa et al., 2022;Mancini et al., 2020;Yılmaz et al., 2005).The authors emphasized that the microbial load of raw hamburgers or meatballs might be related to the meat grinding process, or the addition of spices and other ingredients into minced meat.In the present study, the counts of TMAB, total coliform, and yeast-mold in all groups (except CP1 and CP2 for total coliforms) decreased as a result of the cooking process (p < .05).Yılmaz et al. (2005) noted that initial TMAB load of meatballs decreased by approximately 2-3 log cycles after grilling or oven cooking processes.Lahou et al. (2015) reported that the heating rate applied, nutritional composition (e.g., fat content) of meat material used, and the protective impact of some ingredients due to pH alteration or adaptation capability of microorganisms to stress conditions might have significantly influenced the survival of microorganisms in heat-treated meat products. In did not cause a significant change.Similarly,Kim et al. (2019) stated that fresh garlic incorporation into pork patties increased pH values.Moreover, BC had a lower (p < .05)pH compared to CP1, CP3, CP5, and CP8 groups on day 15.pH values generally increased in all groups (except control and BC) during the first 15 days of storage (p < .05).An increase in pH may be due to protein degradation that occurred as a result of the dissociation of bonds containing hydroxyl, sulfhydryl, and imidazole groups(Khan et al., 2019).Conversely, significant pH decreases (p < .05)were observed on days 30 and 60 for all groups.Similarly,Yingyuad et al. (2006) observed that pH values of vacuum-packed grilled pork gradually decreased during storage.
generally higher b* values than those of CP1, CP2, CP3, and CP4 (p < .05).b* values of control, CP1, CP4, CP6, CP7, CP8, and CP9 were generally stable during storage.Likewise, Kök and Çiçek (2022) observed that there was no significant change in b* values of meatballs containing fenugreek paste during the 5 days of processing stage.Additionally, b* values of BC gradually decreased during storage (p < .05).Moreover, b* values of CP2 decreased during the duration of day 30 to day 60, whereas b* values decreased on day 15 compared to day 0 for groups of CP3 and CP5 (p < .05).

(
N) value compared to CP4, CP6, and CP7 (p < .05).TPA showed a gradual increase (p < .05) in hardness (N) values during storage in groups (except control and CP5), whereas resilience and cohesiveness values of all groups were quite stable during storage.Adhesiveness (N sec), springiness, gumminess (N), and chewiness values of groups generally increased on day 60 compared to production day (p < .05).

Table 4
Qureshi et al. (2018)asmeans±SD; a-e Means with different superscripts within a column are significantly different (p < .05).A,B Considering the different cooking states for each of the proximate compositions; means with different superscripts within a row are significantly different (p < .05).CP8, and CP9 (p < .05).Patriani et al. (2023)noted that FSF addition to buffalo meat patty caused a decrease in pH.The authors also stated that the rate of pH decrease caused by FSF addition was more evident with the increasing FSF dose incorporated.Similarly,Hegazy (2011)stated that FSF usage in hamburgers eventuated a lower pH.Conversely,Qureshi et al. (2018)indicated that the use of FSF in spent hen meat patties caused higher pH values.Furthermore, , the highest pH was obtained in control and BC groups on day 0, whereas the lowest pH was determined in CP7, TA B L E 3 Effects of breadcrumbs or çemen paste addition on proximate composition (%) of hamburgers.Note: Table 5) showDinçer et al., 2018)L* values on days 0 and 15 were obtained in control compared to other groups (p < .05).Moreover, control and BC had the highest (p < .05)L*valuesduring the rest of the storage.Hamburgers containing çemen paste had lower L* values compared to control and BC in all storage days (p < .05).Several researchers have noted L* values decrease due to retrograded and cocoa shell flour usage in patties (Delgado-Ospinaet al., 2022;Dinçer et al., 2018).There was no difference in L* among Effects of breadcrumbs or çemen paste addition on CIE L* a* b* values of hamburgers.
(Cachaldora et al., 2013;Martínez, Djenane, et al., 2006b)lues on days 0 and 15 than other groups (except CP6 on day 0).This result is thought to be related to higher SRP and lower FSF content in CP9 formulation.Similar results were demonstrated byMartínez, Cilla, et al. (2006a)who noted that SRP addition to sausages increased a* values.This effect is due to the high carotenoid content of SRP, mainly ketocarotenoids such as capsanthin and capsorubin(Martínez, Cilla, et al., 2006a).On day 30, there were no significant a* value differences between control and groups containing çemen paste.Moreover, BC had generally lower (p < .05)a*valuethanthose of other groups (except CP1 on day 0, CP1 and CP2 on day 15, and CP1, CP2, and CP3 on day 30) during the first 30 days of storage.Similarly,Ergezer et al. (2014)observed that control had higher a* values compared to meatballs containing BC, which was associated with the dilution of the meat pigment due to BC. a* value of CP9 on day 60 was higher than those obtained in control, BC, CP2, and CP3 (p < .05).Considering the storage period, the groups (except BC TA B L E 4 Effects of breadcrumbs or çemen paste addition on pH values of hamburgers.Note: Results are expressed as means ± SD; a-f Means with different superscripts within a column are significantly different (p < .05).A-D Means with different superscripts within a row are significantly different (p < .05). and CP1) did not generally exhibit a significant change in a* values during storage.a*valuechangesdetermined in this study were similar to those noted by several researchers(Cachaldora et al., 2013;Martínez, Djenane, et al., 2006b).Color results (Table5) indicated that the lowest b* values were observed in control during the first 30 days of storage followed by those of BC (p < .05).On day 60, control and BC had the lowest b* values (p < .05).These results showed that çemen paste usage in TA B L E 5

Table 6
cooked hamburgers, control and BC had TMAB counts similar Effects of breadcrumbs or çemen paste addition on TBARS and LPO levels of hamburgers.Effects of breadcrumbs or çemen paste addition on microbiological counts of hamburgers.Results are expressed as means ± SD; a-f Means with different superscripts within a column are significantly different (p < .05).A-D Means with different superscripts within a row are significantly different (p < .05).
count differences between BC and groups containing çemen paste (except CP1) on day 0. Generally, no significant coliform count difference was determined among groups on day 30.The lowest coliform count was obtained in control on day 60 (p < .05).Moreover, BC had lower coliform count compared to CP1, CP4, CP7, and CP9 (p < .05).Coliform counts only determined in CP4, CP6, and CP9 increased on TA B L E 6 Note: Results are expressed as means ± SD; a-f Means with different superscripts within a column are significantly different (p < .05).A-D Means with different superscripts within a row are significantly different (p < .05).day 60 compared to production day (p < .05).On day 0, yeast-mold count of control was higher than those of BC, CP2, CP3, CP4, CP5, and CP6 (p < .05).CP2 and CP4 groups had higher (p < .05)yeast-moldcounts on day 30 compared to BC and control.Moreover, the lowest yeast-mold counts on day 30 were determined in CP1, CP7, CP8, and CP9 (p < .05).There was generally no significant yeast-mold count difference among groups (except BC) on day 60.Yeast-mold counts obtained from CP4, CP6, and CP8 increased on day 60 compared to production day, whereas yeast-mold counts of control, BC, and CP9 decreased on day 60 (p < .05).TA B L E 7