The effects of elevation and soaking conditions on dry bean cooking time

Dry beans and other pulses (e.g., chickpeas and cowpeas) are nutrient‐dense foods that promote human and environmental health. However, consumption is declining in many regions around the world. Addressing barriers to greater pulse intake is important to reverse this trend. Cooking time is one such barrier, with consumers viewing the long cooking times of many pulses as a hurdle to higher consumption due to lack of time or fuel availability. Equipping consumers with simple, accessible ways to reduce pulse cooking time is one way to mitigate this barrier. Accordingly, this study assessed changes to cooking time when pinto beans (Phaseolus vulgaris L.) were cooked at four elevations using different soaking conditions, which reflect a combination of the soaking method and salt added to the soaking solution. There were seven different cooking conditions: soaking via the overnight or quick soak method in only water or in 1% sodium chloride (NaCl) or sodium bicarbonate (NaHCO3) solutions and a no soak with no salt added comparison. Using an overnight (12‐h) soak or a quick soak resulted in similar reductions in cooking time compared to unsoaked beans. Soaking in NaCl and NaHCO3 solutions further decreased cooking time than when only water was used, with the shortest cooking times seen for NaHCO3. Elevation also impacted cooking time, with the longest cooking time being for unsoaked beans at the highest testing elevation. Adding either salt to the soaking water reduced the effect of elevation. This information was synthesized to give consumers practical tips to reduce cooking time.


| INTRODUCTION
Beans and other pulses (i.e., the dry, edible seeds of non-oilseed legumes like chickpeas, cowpeas, dry peas, and lentils) are nutrientdense foods positioned to help simultaneously improve the well-being of people and the planet (Foyer et al., 2016).Due to the wide variety of environmental benefits (Foyer et al., 2016;Peoples et al., 2019;Stagnari et al., 2017) and positive public health outcomes with which they are associated (Didinger et al., 2022;Mitchell et al., 2021), combined with their relatively affordable price point, one might expect that pulse consumption is high.However, intake in many countries is low (Rawal & Navarro, 2019), which prevents capitalization on the myriad benefits that greater incorporation of pulses into food systems could provide.Some reasons for this sub-optimal consumption level are barriers that consumers face (Didinger & Thompson, 2020;Doma et al., 2019;Henn et al., 2022).Paramount among these is the long cooking time of pulses (Didinger & Thompson, 2020;Henn et al., 2022;Szczebyło et al., 2020).Depending on the audience, long cooking time can present a challenge due to fuel scarcity or a perceived lack of time and thus inconvenience when preparing pulses (Cichy et al., 2019).Mitigating the barrier of long cooking times via disseminating practical tips centered around consumer-accessible cooking methods is one way to address this concern and help enable higher pulse consumption and the associated health advantages.It is also valuable to provide clarity on potential points of consumer confusion surrounding cooking dry beans, such as how different factors (e.g., elevation and cooking method) impact cooking time, to help ensure a more positive cooking experience.
To achieve this, it is important to synthesize research findings to date to determine what methods can affect cooking time.The current literature demonstrates that soaking beans is a practical way to reduce cooking time (Jeffery et al., 2023;Martínez-Manrique et al., 2011;Wood, 2017).Evidence also supports the addition of salts to the soaking water as one way to further reduce cooking time.The types of cations present in the soaking solution can impact cooking time, and soaking in bivalent salts-like those with Ca ++ solutionsincreases cooking time, whereas soaking solutions of monovalent salts like Na + can result in quicker softening (Njoroge et al., 2016).One potential mechanism proposed to explain this is the cross-linking between calcium ions and pectin, which can form insoluble pectates, resulting in resistance to water absorption (Kinyanjui et al., 2015;Njoroge et al., 2016).
Njoroge and colleagues found that soaking in sodium carbonate (Na 2 CO 3 ) reduced cooking time (Njoroge et al., 2016).Similarly, Cos ¸kuner and Karababa (2003) studied the effects of soaking on chickpeas and demonstrated that both sodium chloride (NaCl) and sodium bicarbonate (NaHCO 3 ) shortened cooking time, generally with greater reductions when using NaHCO 3 .Bhokre and Joshi (2015) found that soaking cowpeas in water, a 1% NaCl solution, and a 1% NaHCO 3 solution resulted in reductions in cooking time of approximately 51%, 66%, and 86%, respectively, compared to unsoaked samples.The investigators found a similar trend for horsegram, with reductions of about 13% for water only, 31% for NaCl, and 45% for NaHCO 3 compared to unsoaked, as well as in mothbean, with 20%, 50%, and 80% decreases in cooking time.Although some studies have found slight increases in cooking time or hardness when soaking in salt solutions with NaCl and/or potassium chloride (KCl) ( Ávila et al., 2015;Kwofie et al., 2020), these same studies have found decreases in cooking time when using soaking solutions with NaHCO 3 ( Ávila et al., 2015) and potassium carbonate (K 2 CO 3 ) (Kwofie et al., 2020).Some of these differences could be attributed to different study designs.For instance, diverse pulses are used and cooking time is measured in different ways, such as the tactile (i.e., finger pressing) method and via a device like a Mattson cooker (Wood, 2017).Another potential reason is the different pH of soaking solutions.Alkaline solutions may act as tenderizers (Kinyanjui et al., 2015), enhancing pectin solubilization, helping cells separate better during cooking, and reducing cooking time (Njoroge et al., 2016).Overall, soaking solutions that contain monovalent salt solutions appear to reduce cooking times, although NaCl sometimes is not found to have an effect (Kinyanjui et al., 2015).
Reducing cooking time with salt treatments represents a practical approach for consumers because many of these salts (e.g., table salt and baking soda) are common household items.Some websites known for food science and culinary tips, like America's Test Kitchen and Serious Eats, purport the benefits of adding salt to bean soaking water (America's Test Kitchen, n.d.;Gritzer, 2023).Yet, there is still a common belief among the public and culinary industry that the use of salt in soaking water can prevent softening, and this information is repeated even on the websites of organizations that share knowledge about how to cook pulses (Alberta Pulse Growers, n.d.; Pulses Asia, n.d.).Such inconsistent messaging can result in confusion and is clearly not successful in equipping consumers with practical, evidence-based tips to mitigate an important barrier to pulse consumption: long cooking times.
Elevation is another factor that can significantly impact cooking time, with longer times seen as elevation increases (Bressani & Chon, 1996;Sadohara et al., 2022).However, the main study that examines cooking times at different elevations was published in 1996, used finger pressing and biting to assess cooking time, cooked samples in drinking water (which could vary by site location), and did not evaluate the impacts of different soaking methods or solutions (Bressani & Chon, 1996).In contrast, the current study used a Mattson cooker to standardize cooking time data collection.To the best of our knowledge, no studies have investigated the interaction between elevation and cooking condition.For the purposes of this paper, the cooking condition represents the combination of soaking time (i.e., overnight soak or quick soak, which are two methods commonly recommended to consumers [The Bean Institute, n.d.]) and salt added to the soaking solution (i.e., none, NaCl, or NaHCO 3 ), with a no soak comparison.
To more effectively enable consumers to cook pulses fasterthereby mitigating a key barrier to higher consumption-it is critical to better understand the influence of cooking conditions and elevation on pulse cooking time.Thus, this study differs from other studies on dry bean cooking times because it is geared toward consumer education.After investigating practical, consumer-accessible cooking conditions at different elevations, findings were synthesized with evidence in the literature to develop a public-facing resource for dissemination through the Extension network.Therefore, a translational approach was adopted to ensure that evidence-based practical tips to reduce pulse cooking time are made available to the public.

| Bean Material
Bean cooking time can vary with genotype (Cichy et al., 2019;Katuuramu et al., 2020;Sadohara et al., 2022).Thus, all seed used was the Monterrey cultivar of pinto bean.Beans were grown in Idaho the period of time it takes for beans to be processed and packed, and how long beans would be stored after harvest before being cooked by consumers.

| Cooking conditions and locations
To replicate common and accessible cooking conditions consumers may use in their homes, three different soaking times were used: (1) an overnight soak (i.e., soak beans for 12 h at room temperature and then discard the soaking water and cook in fresh water), ( 2 This reflects the 1% soaking solution used in other studies that assess cooking time (Bhokre & Joshi, 2015;Cos ¸kuner & Karababa, 2003).
Thus, three different soaking solutions were tested with the overnight soak, three with the quick soak, and a no soak condition, resulting in seven cooking conditions, as shown in Figure 1.For each condition that included soaking, approximately 20 g of seed was measured and soaked in a 1:4 w/w ratio (i.e., 20 g beans and 80 g soaking solution).
All seven conditions were tested at four different locations with different elevations, as shown in Table 1.The lowest elevation was East Lansing, close to sea level (263 m), and the highest was in Leadville, at over 3000 m.

| Assessing cooking time
An automated Mattson cooker was used to measure cooking time (Wang & Daun, 2005), as this is a standard way to assess the cooking time of pulses (Bassett et al., 2017;Wiesinger et al., 2021;Wood, 2017).Briefly, a Mattson cooker contains 25 pins that align with the base plate, which contains 25 wells that can hold one bean each.The following video demonstrates the operation: https://www.youtube.com/shorts/3rMvHuVxKDA.After the beans had been prepared according to their cooking conditions, they were added to the wells of the Mattson cooker.Evenly weighted (approximately 63 g) piercing rods rest on top of the center of the bean in each well.The cooker was then placed into a beaker of fresh boiling distilled water on a burner.Individual beans are considered cooked when they soften enough that they are pierced by the rod, and the Mattson cooker program automatically records the pin drop time.The cooking time of the sample is determined to be when 80% of the beans have been pierced by the rods, and this has been found to equate to fully cooked samples based on mouthfeel as determined by a trained sensory panel (Bassett, Hooper, & Cichy, 2021;Bassett et al., 2017;Cichy et al., 2019).Each cooking condition was conducted in replicate to calculate the average cooking time for a condition.Due to the extended Each blue circle represents one of the seven cooking conditions, as explained in the text.
T A B L E 1 Elevation of different testing sites and the boiling temperature of water at that elevation.and Colorado, a John Deere Grain Moisture Tester.2.

| Statistical analysis
Table 3 shows the average water uptake rates for the different cooking conditions at the four locations and the average pH of the soaking solution at the end of the soaking period.The no salt, no soak condition is not shown because a water uptake measurement could not be taken due to no soak occurring.Michigan (elevation 263 m) conducted two batches of three runs for each condition, separated by 1 month.
The temperature of the soaking water is one of the main factors that influences the hydration process, with higher temperatures accelerating hydration (Miano et al., 2018).Thus, water uptake values are provided, but a statistical test evaluating the impact of elevation and cooking condition is not conducted, as this would not account for ambient temperatures, which varied with location and season.
As shown in Table 3, the average water uptake tended to decrease as the beans aged.This is apparent when comparing the same cooking condition in Michigan in December 2021 versus January 2022.Although similar, the pH of the NaCl soaking solution was slightly lower than that of soaking in water with no salt added.
When comparing the quick soak and overnight soak within the same soaking solution (i.e., same salt), the quick soak appeared to have a higher pH.This difference was the most pronounced for the NaHCO 3 conditions.
T A B L E 2 Average cooking times for cooking conditions at different elevations.Cooking times are shown in minutes ± SD.This is reflected by readings that were lower than the moisture content of the same seed (that had been stored in a sealed container) when tested several months later in Michigan and Nebraska, when it would be expected that older seeds should have a lower moisture level.

| Cooking time varies with cooking condition and elevation on cooking time
As shown in Figure 2, cooking time is reduced with soaking and further reduced by the addition of salts to the soaking water.
Levene's test of equality yielded a significant result, which is addressed in the discussion.The ANOVA analysis demonstrated that elevation and cooking conditions were significant main effects (see Table 4).The interaction effect for cooking condition*elevation was also found to be significant, indicating that the impact of the cooking condition depends on elevation.The non-parallel lines in Figure 2 are also indicative of an interaction effect.Due to the large number of pairwise comparisons, results are not displayed in the paper but are available in Supporting Information S1, which breaks down the cooking time trials by the four elevations and shows which cooking conditions result in significantly different cooking times at each elevation.
For example, at the lowest elevation, the cooking condition of quick soak, no salt was found to be significantly different from the comparison condition of no soak, no salt ( p < .001)but not the overnight soak, no salt condition ( p = 1.00).
To investigate the interaction effect, conditions were examined separately, comparing the tests conducted on the same condition among the four different elevations.For the no salt, no soak condition, a quadratic fit (R 2 = 0.986) was better than a linear fit (R 2 = 0.858), as shown in Figure 3.The summary of the R 2 values is shown in Table 5, which demonstrates that quadratic is a better fit than linear for all the cooking conditions.
T A B L E 3 Average water uptake and pH.

| Percent changes in cooking time
Due to evidence of a significant interaction between elevation and cooking time, it is not advisable to statistically analyze the impact of elevation or cooking condition on cooking time.Instead, pairwise comparisons are shown in Supporting Information S1.However, to begin to evaluate the impacts the elevation and cooking condition may have on cooking time, percent change calculations were made.
The percent increase in cooking time for each condition was calculated with increasing elevation, using the lowest elevation as the comparison.Table 6 shows the percent increase in cooking time that can occur with higher elevation.The longest cooking times occur at the highest elevation and are over 200% greater than those at the lowest elevation.F I G U R E 3 Linear and quadratic fits for the no salt, no soak cooking condition.
T A B L E 5 Cooking condition curvilinear regression.interaction effect.Depending on the elevation, the average reduction compared to the no soak condition ranged from 41% to 56% for soaking in only water, 45%-67% for the sodium chloride soaking solution, and 54%-77% for the sodium bicarbonate soaking solution.The greatest reductions in cooking time were seen when the beans were soaked in a 1% sodium bicarbonate solution.Although similar reductions were seen for the overnight and quick soak soaking methods for most elevations, there was greater variation between these two times for the 1200 m (Nebraska) location.
Table 8 shows the percent reduction in cooking time that can occur by adding different salts to the soaking solution.Compared to cooking conditions with no salt added to the soaking water, adding sodium bicarbonate resulted in greater reductions in cooking time than adding sodium chloride.
As shown in Tables 6-8, the trends in changes to cooking time at the Nebraska location (1200 m) appeared to differ from the other three locations.For example, in Table 7, the average reduction of NaCl versus only water was 67% for the Michigan site close to sea level, 62% and 61% for the two sites in Colorado, but 45% for Nebraska.
This was similar for the NaHCO 3 solution compared to no salt added to the soaking water, with Nebraska showing a 54% reduction and the other three sites having reductions of 77%, 74%, and 77% again.

| Impacts of elevation and cooking conditions on cooking time
The current study provides new insights into the effects of elevation on cooking times.As one would expect, cooking time increases with higher elevations.The previous study by Bressani and Chon (1996) that examined cooking times at several elevations also confirmed this trend, with bean cooking time increasing from 78 min at 0 m to T A B L E 6 Percent increase in cooking time with increasing elevation, compared to the lowest elevation (263 m).264 min at 2256 m, the highest elevation they tested (Bressani & Chon, 1996).They used black beans (Ostua variety) and did not soak prior to cooking; because multiple cooking conditions were not investigated, the interaction between elevation and cooking condition was not examined, whereas this was a focus in the current study.Moreover, the study by Bressani and Chon (1996) used finger pressing and biting to determine the cooking time of dry beans, whereas the current study standardized data collection by using a Mattson cooker.
Nonetheless, some similarities are evident.Interestingly, the cooking times of similar elevations between the Bressani and Chon (1996) study align closely with the cooking times determined for the no salt, no soak condition in the present study.6).A more recent paper that assessed cooking times in two of the same locations as in the current study (East Lansing, MI, and Scottsbluff, NE) also revealed that cooking times were longer in Nebraska, which has a higher elevation (Sadohara et al., 2022), although testing only occurred at two elevations and the interaction of elevation and cooking condition was not assessed.Some of the differences in cooking times could be attributed to the lower temperatures at which water boils as elevation increases (see Table 1).
Another finding that aligns with previous research is that soaking reduces cooking time (Bassett, Hooper, & Cichy, 2021;Jeffery et al., 2023;Martínez-Manrique et al., 2011;Wood, 2017).The ranges in this study for percent reduction in cooking time when soaking in water only (average reductions of 41%-56% depending on elevation, when the quick soak and overnight soak, no salt cooking conditions are combined) were similar to the reduction seen for cowpea by Bhokre and Joshi, 51% (Bhokre & Joshi, 2015).Bhokre and Joshi also witnessed reductions in cooking time of 66% for cowpea and 50% for mothbean when soaking in a 1% NaCl solution when compared to unsoaked samples, which match well with the average reductions seen when NaCl was added to the soaking solution, ranging from 45% to 67% in this study (Table 7).Both Bhokre and Joshi (2015) and Cos ¸kuner and Karababa (2003) found that 1% NaCl and NaHCO 3 soaking solutions reduced cooking times, with NaHCO 3 resulting in the shortest times.The same was found in the current study, where soaking in a 1% NaHCO 3 resulted in up to 77% shorter average cooking times (Table 7).However, none of these prior studies also took elevation into consideration, and testing only occurred at one location.Thus, this challenge that consumers may face was not taken into consideration in previous research.
Conversely, some studies have found that NaCl soaking solutions result in increased cooking times, such as Ávila and colleagues' investigation of cowpea ( Ávila et al., 2015) and Kwofie and fellow investigators' study on common beans (Kwofie et al., 2020).Interestingly, Kwofie and colleagues even comment that the local communities in Malawi use NaCl to help soften beans (Kwofie et al., 2020).However, the current study demonstrated that soaking in NaCl can reduce cooking time, which is in alignment with other studies (Bertoldo et al., 2010;Bhokre & Joshi, 2015;Cos ¸kuner & Karababa, 2003;Schoeninger et al., 2014).These differences could be attributed to differences in pulses and in elements of experimental design, such as the water used (i.e., water with more divalent ions could result in prolonged cooking times [Njoroge et al., 2016]), the exact amount of salts added, and how cooking time was determined.
As beans are stored (especially under high temperature and high humidity) and age, they can develop the hard-to-cook (HTC) defect, which results in longer cooking times.The full reason for this phenomenon is not completely understood, but one of the most plausible hypotheses is the pectin-cation-phytate mechanism (Chigwedere et al., 2018;Kruger et al., 2015;Njoroge et al., 2016).
This model suggests that pectin methylesterase activity causes demethoxylation of pectin, and the hydrolysis of phytate by phytase results in the release of divalent cations, like Ca ++ (Yi et al., 2016).
Cross-linking of these ions with pectin results in pectate compounds that are insoluble or more thermally stable (Chigwedere et al., 2018;Njoroge et al., 2016;Yi et al., 2016).Our findings that both NaCl and NaHCO 3 soaking solutions help reduce cooking time align with the pectin-cation-phytate model for the HTC phenomenon.Both of these soaking solutions contain the monovalent ion Na + , which could play a role in increasing protein solubility and/or ion exchange, replacing some of the divalent cations like calcium and thereby weakening the cross-linkages that slow pulse softening (Pirhayati et al., 2011).
Adding salt to the soaking solution can improve the efficacy of soaking (Azarpazhooh & Ahmed, 2022), but it is also important to consider the impacts on quality aspects, such as texture.Indeed, the different salts appeared to impact the final texture of the beans.
The NaHCO 3 solution resulted in much softer beans that were more prone to losing their firmness and being smooshed.Depending on the desired result and intended use of the beans (e.g., dip and salad), consumers could view this as a positive or negative effect.
The NaCl solution did not seem to impact texture as noticeably.
However, more work on quality aspects and texture should be conducted before drawing conclusions, as the current study was not designed to assess minute differences in final firmness and texture.
This could also include investigation into impacts on nutritional quality and the content of various components such as lectins, oxalates, and tannins.For instance, previous research suggests that soaking in distilled water can significantly decrease the content of lectins and oxalates (Azarpazhooh & Ahmed, 2022;Shi et al., 2018), but the research did not examine different cooking conditions and elevation.
4.2 | Effects of pH and water uptake on cooking time It has also been proposed that pH plays an important role in cooking time, with alkaline conditions promoting β-elimination depolymerization of pectic polymers and improved solubilization (Njoroge et al., 2016).
Indeed, NaHCO 3 soaking solutions had a higher pH (see Table 3), and they also resulted in the fastest cooking times.The results showed that alkalinity was not the only determinant of cooking time, as the pH of the water only and the NaCl solutions were similar, yet the NaCl conditions had faster cooking times.Ultimately, it appears that the type of salt (both the cation and anion) and pH both affect cooking time.
In some studies, differences in water uptake have been attributed to different genotypes (Katuuramu et al., 2020;Sadohara et al., 2022).
This study shows that water uptake clearly differs from other factors, too (see Table 3).For instance, water uptake was often much lower in Nebraska than in Michigan, with average water uptake percentages for overnight soak conditions of 37.1% versus 89.7%.The difference was less dramatic when the quick soak method was used, suggesting that this method may result in more even water uptake.However, this only sometimes resulted in faster cooking times when overnight and quick soak were compared for the same salt added.Slight differences in how the experiment was conducted between sites cannot be ruled out as the cause for the differences seen.For example, the temperature of the soaking water influences hydration, with higher temperatures increasing the hydration rate (Kinyanjui et al., 2015).
This could be one reason for the lower water uptake rate in the higher elevation Colorado site versus the lower elevation location, despite testing having occurred in the same month.Another important factor is starting seed moisture, which should be in the range of 10%-14% for optimal uptake (Cichy et al., 2019).

| Interaction of elevation and cooking conditions
As shown in Table 2, a significant interaction effect was found, indicating that the effect of elevation depends on the cooking condition.
When examining Figure 2, it is apparent that cooking time tends to increase with higher elevation.Yet, for elevations within the same cooking condition, the 95% CI is often overlapping, with the occasional exception of the highest elevation.Levene's test was found to be significant, likely due to factors like limited sample size, variation among sites (e.g., different technicians, temperature, and age of the beans when tested), and the nature of the Mattson cooker procedure.
For instance, for the Mattson cooker procedure, seeds that have imbibed water well are selected to be tested in the cooker, eliminating beans with less water uptake.This cannot be done for unsoaked samples.Also, water uptake varied with quick and overnight soaks.However, it is notable that water uptake percentage was not consistently associated with faster or slower cooking times within conditions, so this may not be of concern.
Table 2 shows that there can be a fair amount of variation for cooking time readings, even within the same elevation and cooking condition (Table 2), with the largest standard deviations evident in the Leadville, Colorado (i.e., the highest elevation) and Scottsbluff, Nebraska locations.As previously discussed, fewer replicates were conducted in Leadville, which could be one reason for this.Also, Nebraska had the latest testing date and the oldest beans, which could cause more of the HTC phenomenon and challenges with quick, even cooking.
When examining different elevations within the same cooking condition, quadratic fits were determined to be more appropriate, as shown in Table 5.However, the difference between the amount of variation accounted for between the quadratic and linear fits decreases with soaking (from about 12.8% for the no salt, no soak condition, to 8.9% and 5.7% for the only water quick and overnight soaks, respectively).

| Development of a consumer resource
One critical new contribution made by this study was the synthesis of findings from the current study with those in the literature to create an Extension handout with practical, accessible information and tips to cook dry beans.The handout specifically addresses the consumer barrier of long cooking times, as well as points of potential confusion to help mitigate confusion and ensure a more positive cooking experience.Thus, in addition to data collection on cooking times, a translational research approach (Woolf, 2008) was incorporated so that helpful information could reach the public, something which previous studies have not done.
It is important to conduct translational research and share findings with the public.Accordingly, the study results and scientific literature were synthesized into a consumer resource (see Figure 4) for distribution through the Colorado State University Extension network.
Most of the literature referenced in the consumer resource has already been discussed in this paper.Additional references cited to distill helpful cooking tips for consumers were about the importance of good storage conditions and avoidance of high heat and high humidity (Pirhayati et al., 2011;Yi et al., 2016), and the fact that acidic ingredients can slow softening (Munthali et al., 2022) and thus should be added at the end of the cooking process.The issue of elevation was also prominently addressed, as many consumers in states like Colorado express challenges about cooking beans, and this could largely be due to the higher elevations at which many individuals live.
By providing consumers with this information, the chances that they have a more positive experience cooking pulses-and can do so more quickly-improves, helping reduce a key barrier to cooking dry pulses and promoting healthy dietary patterns.

| Limitations and future directions
As discussed above, there were several limitations in this study.The Future studies should consider monitoring other variables, such as temperature, that can impact water uptake and potentially cooking time.Also, it would be ideal if the same instruments could be used to assess pH and moisture content.However, when conducting a multisite experiment that also requires travel to locations far from the laboratory (i.e., Leadville, Colorado), some variation is inevitable, which again highlights the need for replication.More preferable would be the development of a procedure that is more robust to inherent variation among technicians and locations.
In addition, future work could investigate the impacts on nutrition of the different cooking conditions.Studies suggest that shorter cooking times can have better nutrition (Wainaina et al., 2021;Wiesinger et al., 2018), which adding salts like NaCl and NaHCO 3 to the soaking solution can help promote.At the same time, it would be important to know how much sodium is contributed by adding these salts, especially for those on salt-restricted diets.Moreover, other research has found that soaking in an alkaline solution (as would be the case with NaHCO 3 ) can result in the leaching of vitamins like thiamin, riboflavin, and niacin from legumes, although the actual amount varied with the type of pulses, and bioavailability was not considered (Prodanov et al., 2004).However, another study found that soaking in NaHCO 3 resulted in improved antioxidant activity (Sikora et al., 2018).Thus, information on the impacts of different cooking conditions on nutritional content for a wide array of pulses would be beneficial, ideally taking into account bioavailability.
Another critical aspect to consider in future research is quality issues, such as impacts on texture.Although the 80% pin drop time F I G U R E 4 Extension handout on how to reduce pulse cooking time.
for the Mattson cooker has been found by a trained sensory panel to equate to fully cooked samples based on mouthfeel (Bassett, Kamfwa, et al., 2021), it would be helpful to collect sensory evaluations to assess whether cooking methods affect consumer perception of aspects such as mouthfeel and flavor, as may happen when salts are added (Amin & Borchgrevink, 2022).If baking soda has any adverse effects, one option is to use baking powder instead, which has also been found to reduce cooking time and improve nutritional and quality properties in fava beans (Abdel-Aleem et al., 2019).
Lastly, studies on the effect of the Extension consumer resource on actual behavior change and pulse preparation and consumption habits could benefit future translational work.Surveys to collect this data could be integrated into research.

| CONCLUSIONS
Increasing pulse intake can offer a host of benefits for both human and environmental well-being.To make higher pulse intake more accessible and attractive to consumers, it is important to address potential barriers to intake.Long cooking time has been established as one of the major barriers faced by the public.Shorter cooking times are more convenient, and they may help preserve nutrition.Plus, they result in more efficient fuel utilization, which is especially important in regions where access to fuel is limited and those preparing the food are exposed to higher levels of pollution due to exhaust from the cooking processes.This research provided insights into the effects of elevation and several different, consumer-accessible cooking conditions that can greatly reduce cooking time, making the cooking of dry pulses more feasible.Providing the public with simple, affordable, consumer-accessible tips to shorten cooking time is a key step in mitigating the large barrier that cooking time poses to more pulse-centric diets.Thus, results were synthesized along with findings from the literature to create a handout for consumers that is being disseminated through the Extension network.
under sprinkler irrigation, and certified, untreated seed was obtained from Kelley Bean Co.The seed was harvested in fall of 2020 and procured in late spring of 2021, and cooking time tests occurred in summer of 2021 through winter of 2022.This is reflective of the shelf-life of beans (United States Agency for International Development, n.d.), the Leadville location, most cooking conditions were only tested in duplicate.Other locations conducted tests in at least triplicate to calculate an average cooking time for each condition.2.4 | Water uptake, pH, and moisture content Water uptake was calculated by obtaining the weight of (1) the dry seeds and (2) the seeds after soaking, by first draining and blotting them dry.The formula used to determine the percent water uptake on a dry basis was: (soaked weight À dry weight)/(dry weight) Â 100.Before soaking, the moisture content of the dry beans was recorded.Measurements of the pH of the soaking solution at the beginning and end of the soaking time were taken.Due to the research occurring in multiple sites, the equipment used differed among research teams.To measure pH, the team in Michigan used pH test paper strips; Nebraska, a Corning pH meter 440; and Colorado, a Dr. Meter pH Meter (due to needing to travel off-site for testing at the highest elevation).For moisture level, the Michigan team utilized a Dickey-John GAC 2500UGMA; Nebraska, a Dickey-John GAC 2100b; Statistical analyses were conducted in IBM SPSS Statistics version 28 (IBM Corp. Released 2021.IBM SPSS Statistics for Windows, Version 28.0.Armonk, NY: IBM Corp.).To evaluate the effects of elevation and cooking conditions on bean cooking time, a two-way analysis of variance (ANOVA) was conducted, with cooking time as the dependent variable.Cooking condition and elevation were considered main effects, and the interaction between elevation and cooking condition was also assessed.Due to the large number of comparisons being made, pairwise comparisons were calculated using the more conservative Bonferroni test.Descriptive statistics, such as average cooking time for the seven cooking conditions at each elevation, were also computed in SPSS.For analyses within individual conditions, a curvilinear regression was conducted.Percent changes in cooking time were calculated in Excel, using mean cooking times for each condition at each elevation.The following three comparisons were made: 1. Increases in cooking time seen with higher elevations: Percent increase in cooking time for a cooking condition = (site 2 mean À site 1 mean)/(site 1 mean) 2. Decreases in cooking time seen with soaking: Percent decrease in cooking time = (mean cooking time for the no soak condition À mean cooking time for comparison condition)/(mean cooking time for the no soak condition) 3. Decreases in cooking time seen with salt added: Percent decrease in cooking time = (mean cooking time for salt 1 À mean cooking time for salt 2)/(mean cooking time for salt 1) 3 | RESULTS 3.1 | Average cooking time, water uptake, pH, and moisture content(S Cooking times (in minutes) ± standard deviation (SD) for the different cooking conditions at all four elevations are shown in Table The age and moisture content of the seed influences water uptake, hence cooking time tests were conducted as close together as possible and moisture content was assessed.Average moisture content fell within the standard range of 10%-14% used with Mattson cooker trails(Cichy et al., 2019;Sadohara et al., 2022).As the table caption states, the moisture levels reported for the two Colorado locations are likely lower than the actual moisture content.

F
I G U R E 2 Cooking time varies with cooking condition and elevation.Plotted cooking times (minutes) are average cooking times for a particular cooking condition at the specified elevation, with error bars showing ± standard error (SE).NaCl, sodium chloride soaking solution; NaHCO 3 , sodium bicarbonate soaking solution; OS, overnight soak; QS, quick soak.
For instance, at 229 m, Bressani and Chon determined the cooking time to be roughly 84 min, and this study found pinto bean (Monterrey variety) cooking time to be about 88 min at 263 m.Bressani and Chon also found the cooking time to be approximately 124 min at 1234 m and 129 min at 1524 m, and our study revealed approximate cooking times of 111 min at 1200 m and 131 min at 1569 m.Thus, similar percent increases in cooking time (for no salt, no soak) were seen with rising elevation as those in the current study (Table Figure2combined with the significant result for Levene's test suggest that the Mattson cooker procedure, although informative for trends in

Table 7
Summary of the ANOVA for bean cooking time.
shows percent changes with different soaking conditions compared to the no soak condition.Soaking reduced cooking time compared to the no soak condition.The percentage of the reduction varied with cooking condition and elevation, as suggested by the T A B L E 4 Note: Statistical significance when p < .05.Abbreviation: df, degree of freedom.
Percent reduction in cooking time with soaking versus no soak.
Note:The average reduction represents the average of the quick and overnight soaks for the salt added to the solution (none, sodium chloride, or sodium bicarbonate).NaCl, 1% sodium chloride soaking solution; NaHCO 3 , 1% sodium bicarbonate soaking solution.T A B L E 8 Percent reduction in cooking time with salt added to the soaking solution, compared to other solutions.Note:The average reduction represents the average of the quick and overnight soaks for the salt added to the solution (none, sodium chloride, or sodium bicarbonate).NaCl, 1% sodium chloride soaking solution; NaHCO 3 , 1% sodium bicarbonate soaking solution.