A recent paper published by Virginia State University’s Agricultural Research Station compared how different cooking methods affected the nutritional value of U.S. grown chickpeas 1. The cooking methods they tested included pressure cooking, microwave cooking and roasting chickpeas (both soaked and unsoaked). The results are surprising and the data is filled with interesting nuggets of information about how pressure cookery affects the nutritional properties of chickpeas.
Chickpeas are a low-glycemic index food with confirmed health benefits that include reduction of diabetes risk, cardiovascular disease, and some cancers. Proper preparation and cooking of chickpeas can increase their nutritional profile by improving protein digestibility and destroying anti-nutritional components.
hip info: anti-nutrient roundup
Anti-nutrients are compounds or minerals that prevent nutrients from being absorbed and/or utilized by the human body. It’s generally recommended that they be avoided; though, in some circumstances (small quantities and in the presence of other nutrients and minerals), anti-nutrients could have beneficial effects. Here two anti-nutrients that were measured in this study…
Dr. Xu and her team tested both dried and soaked chickpeas. The soaked chickpeas were immersed for 16 hours using 10 cups of water for every cup of chickpea. Then, they pressure cooked each batch using: a Presto Pressure Cooker for 20 minutes (using 5 cups of water for every cup of chickpea); a 2450MHz Microwave where they zapped them 15 minutes (in a bowl with the same water ratio); and, also roasted a batch in the oven at 400°F for 30 minutes.
Researchers measured the chickpea’s chemical composition, amino acid proﬁle, mineral concentration, anti-nutritional factors, protein solubility and in vitro digestibility. They performed each test three times.
Although the paper lauds microwaving chickpeas as a way to preserve the most nutrients – the paper’s own data shows that the nutrients retained by pressure cooking weren’t so shabby. The first table in the paper, for example, shows that soaked and pressure cooked chickpeas retained significantly more crude protein (25.8g/100g dry weight) than the microwaved (21.8g). Unsoaked microwaved chickpeas fared a bit better (24.8g) but still did not beat the pressure cooker.
However, another table in the paper compares amino acid profiles and shows higher retention of most amino acids (the building blocks to make protein) in the soaked and microwaved chickpeas compared to the other processing methods that were measured.
Unsoaked pressure cooked chickpeas were at an advantage in mineral composition after cooking: they retained more of five minerals measured out of nine; equalled or beat some microwaved chickpea preparations for two; and, only retained fewer minerals than zapped chickpeas for two of the remaining measured minerals.
When they tested for In Vitro Protein Digestibility (IVPD). The paper reported that…
… IVPD was signiﬁcantly improved by all treatments except non-soaking/roasting. The order of the digestibility increase in processed seeds was: soaking/pressure cooking, (26.5 %), soaking/microwave cooking (24.3 %), non soaking/pressure cooking (18.9 %), non-soaking/microwave cooking (17.0 %), soaking/roasting (9.64 %), non-soaking/roasting (3.93 %).
The pressure cooker tied with the microwave in destroying anti-nutrients. While microwaving soaked chickpeas reduced the most tannins, all pressure cooker preparations (soaked and unsoaked) reduced more phytates than the microwave.
While this paper concludes that microwaving chickpeas created a more favorable nutrient and anti-nutrient profile, a detailed look at the data shows only a marginal win over pressure cooking. But, there wasn’t any data comparing plain ‘ol boiled chickpeas.
I contacted Dr. Xu, and she sent me a copy of her previous paper2 which compares processing methods (boiling, pressure cooking and microwave) and chickpea nutrition but this paper declared the pressure cooker as the winner.
Pressure cooking is the best method for particular chickpea seeds currently under this study to maintain nutritional and functional qualities.
So… what’s going on?
Well, the two papers measured different chickpea nutritional properties. For example, in the 2014 paper the researchers measured resistant starch (which we already know is a good thing), fiber content, plus emulsification and foaming stability (useful for industrial food production applications) for three different chickpea varieties. So basically each paper ran a different set of tests on different kinds of chickpeas.
Bottom line: Pressure cooking and microwaving chickpeas lead to similar good-for-you results. The winner depends on which nutritional properties are measured and what cooking method you are most comfortable using.
now, pressure cook some chickpeas!
- Visit the new Pressure Cooker Nutrition section of this website, where we report on the latest research!
References & Citations
1. Xu, Yixiang, et al. “Nutritional and anti-nutritional composition, and in vitro protein digestibility of Kabuli chickpea (Cicer arietinum L.) as affected by differential processing methods.” Journal of Food Measurement and Characterization: 1-9.
2. Xu, Yixiang, Melissa Thomas, and Harbans L. Bhardwaj. “Chemical composition, functional properties and microstructural characteristics of three kabuli chickpea (Cicer arietinum L.) as affected by different cooking methods.” International Journal of Food Science & Technology 49.4 (2014): 1215-1223.