Agua panela as a relevant source of calcium in Colombia?

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A new review article (published November 2021) by researchers of the Universidad de los Andes (School of Medicine) in Bogota, Colombia [Amaya Montoya et al 2021], mentions an interesting source of calcium: agua (de) panela.

This question I asked myself is, if this could be of relevance to vegans living in Colombia.

Agua panela (aguapanela) is a very popular drink made from water and a block of firm sugar cane juice (called panela). How do you turn sugar cane juice into a block? You boil it.

The article by Amaya Montoya et al. mentions that "agua de panela is an important source of calcium for low SES [socioeconomic status] segments of the Colombian population [i.e. people who have less money]" [Amaya Montoya et al 2021]. Spoiler: I doubt this is true (see below).

Also, just to be clear: panela is the "sugar cane juice block", while agua (de) panela is the drink made with panela (i.e. watered down panela).

Is panela always rich in calcium?

No.

The different types of panela listed in the USDA Nutrient Database list calcium contents of 36 to 90 mg per 100 g of panela [1, 2, 3]. This is a very low amount of calcium. Imagine, that 100 g of panela are about 80 g of pure sugar - you shouldn't eat that much added sugar every day. And the goal for calcium intake is about 1000 mg per day (for adults).

García et al. 2017 write: "NCS [non-centrifugal cane sugar = panela] exhibits a high sucrose [sugar] content (85%) and some additional constituents [...] [such as] Calcium 103 mg/100 g" [García et al 2017]. So, this is similar to the info by the USDA (above).

An article by Jaffé (2015) confirms this, looking at the calcium content of panela and similar "sugar cane juice blocks" from different countries around the world (known by different names such as jaggery, chancaca, kokuto, gur, piloncillo, rapadura, muscovado, black sugar etc.). Jaffé states that the average (mean) calcium content of non-centrifugal cane sugar (NCS) is around 100 mg of calcium per 100 g of "sugar block" (with a range of 14 to 240 mg of calcium/100 g). And he adds: "the wide range of values for calcium [in panela] probably reflect the variable use of lime [calcium hydroxide] for the clarification of the sugarcane juice in the manufacturing process of NCS. [...] The following general conclusions can be drawn. Calcium, chloride and potassium are present in the order of 100 mg/100 g [...]." [Jaffé 2015].

The types of panela that contain a lot of added calcium (like the upper range of 240 mg of calcium/100 g) can be considered relevant sources of calcium. But they shouldn't be considered a major or main source of calcium because it is not ideal to consume large amounts of sugar (or panela).

Does panela always contain added calcium?

No.

Panela is only rich in calcium if it contains added calcium - added during the clarification process. But calcium isn't always added. Instead of calcium, other alkalizing substances are sometimes be used. It is also possible that some manufacturers do not add any alkalizing substances.

The Spanish Wikipedia article on panela mentions that in the step of clarification of the sugar cane juice the calcium is added:

"Clarification: The sifted juice, known as guarapo, goes through a series of filtering phases to eliminate impurities [...]. The juice is then mixed with calcium hydroxide and phosphoric acid to prepare it for the evaporation phase."

An article by Alarcón et al. (2021; researchers from the Universidad Nacional de Colombia in Bogota) mentions that when panela is granulated (turned into brown granulated sugar) more calcium is used compared to when (and this is much more common) the panela is shaped into hard blocks.

The article states: "In comparison, when the product is granulated NCS [non-centrifugal cane sugar = granulated panela] [...], the syrups are boiled for longer times up to a higher solids content [...], which correspond to a higher bubble temperature (> 125 °C). The operation under these conditions accelerates different chemical reactions. In general, a larger fraction of the reducing sugars (i.e. glucose and fructose) can react to produce different side products affecting the final sugars profile. Therefore, to reduce hydrolysis of sucrose to reducing sugars, the operation is conducted under higher pH levels (> 6). In this case, a higher amount of calcium hydroxide or calcium carbonate is added [when making granulated panela] with respect to that used in bricks manufacturing [blocks of panela]" [Alarcón et al. 2021]

Velásquez et al. (2019) provide some more info:

"Agronomic management and maturity state of the sugarcane has an effect on the pH of the juices [...]. The addition of pH regulators and their incidence on sucrose glycolysis has been studied [...] [and] [t]his study showed that an increase in pH (≥6.0) in sugarcane juice causes a marked darkening of NCS [non-centrifugal sugar = panela] [...]. Regarding coagulation, an alkaline medium must be guaranteed using agents such as calcium oxide (quicklime), sodium hydroxide (slaked lime), sodium carbonate, sodium hydrosulfite and sodium bisulfite; however, these last two are prohibited [...]. The alkalizing agents are usually dissolved in small amounts of water and added to the pan at the boiling point. The addition of the reagents modifies the pH of the juice and with temperature precipitates are formed, eliminating impurities [...]. Consequently, particles are flocculated on the surface of the juice during boiling forming a foam, which is removed using physical means such as ladles, fine meshes or passing a thin cotton cloth through the juice." [Velásquez et al. 2019]

Gómez Narváez et al. 2019 write:

"The pH in panela ranged from 5.3 to 7.1. Granulated and block panela samples showed similar average values [...]. The pH parameter is a critical variable during manufacturing of panela regardless granulated or block. The pH of fresh cane juice must be increased from 5.0 to 5.2 to at least 5.8 to clarify efficiently the juice [...], thus eliminating the impurities and insoluble solids in suspension (called cachaza). The addition of a suspension of lime (calcium oxide) or sodium bicarbonate allows the production of panela with lighter colour and avoids the hydrolysis of sucrose. A pH between 6.0 and 6.5 is required to ensure a product free of cachaza which is a quality criteria for identification of defective panela." [Gómez Narváez et al. 2019]

Is panela always vegan?

No. Some manufacturers of panela seem to add a small amount of "manteca" (lard or butter - I assume, butter). So, not all panela seems to be vegan.

What else did the article from Colombia say?

The article by Amaya Montoya et al (2021) (mentioned at the very beginning) is about major food sources of vitamin D and calcium - two nutrients that are very relevant for everyone - but especially also for vegans.

Below you can see some interesting excerpts from the article:

"Data on dietary calcium and vitamin D intake from Latin America are scarce. [...] We studied 1554 participants aged 18 to 75 from five different geographical regions [in Colombia]."

There article also notes that there is and vitamin D-fortified dairy milk (unlike in Europe) and there are vitamin D-fortified breakfast cereals (probably something like Kellogg's products (?)).

"Analyses by city showed a remarkable variability in vitamin D sources, especially non-dairy (1-13%) and fortified dairy (21-36%) drinks. "

"Dairy products were consistently the main source of calcium, contributing with at least 48% [...]. Within this food group, hard cheese contributed the most (12.9%-22.1%). [...] The highest education group consumed 8% more calcium from dairy and 5% less calcium from non-dairy drinks than the lowest group [..]. In Barranquilla, dairy products provided 66% of all calcium intake, mainly due to the contribution of hard cheese (39% of all daily calcium). In Cali, traditional Colombian pastries were the first individual source of calcium (11.2%)."

"[...] the main food sources of vitamin D in the whole sample were dairy products (37.6%) and eggs (24.3%)".

"Cheese is a great source of calcium from the nutritional viewpoint, however, it can be very expensive in urban environments. This could explain why people with high SES [socioeconomic status] and higher education consumed more dairy products and showed the highest calcium intake. Among the lowest SES and educational segments, we found a greater intake of non-dairy products, the main of which is “agua de panela”. Agua de panela is a sweet typical Colombian beverage, made by suspending panela, a solidified block made from sugar cane juice, in water. During the elaboration of panela, sugar cane juice is added with calcium hydroxide, in order to avoid the hydrolysis of sucrose, and to improve the hardness and portability of the product [.]. Therefore, agua de panela is an important source of calcium for low SES segments of the Colombian population." [Amaya Montoya et al 2021]

Take home message

Panela itself and agua panela should not be regarded as a major source of calcium. Even if we assume that high-calcium panela contains around 250 mg of calcium per 100 g, it is not advisable to consume 100 g of panela every day.

Panela is only rich in calcium if it contains added calcium - added during the clarification process.

Vegans should make sure to get enough calcium in their daily diets - which is easy if you know how. Vegans should also make sure they get enough vitamin D - either from supplements or sunshine (easy in Colombia) or both. Recommendations regarding important nutrients for vegans can be found here: English / Spanish.

And here's a graphic from the study in Colombia: