Portobello Mushrooms 101 – The Basics

About Portobello Mushrooms
Portobello mushrooms are the mature stage of the edible fungus Agaricus bisporus. This is the same type of mushroom as button mushrooms, which are the baby form, and cremini mushrooms, which are the mid-growth state. They are all the same species of mushroom, but at different stages of maturity.

You may notice that there are two spellings of the name: portabella and portobello mushrooms. Both versions are accepted. However, to establish some sense of consistency, the Mushroom Council adopted the “a” version of spelling.

Portobellos are native to Italy, and have been growing since ancient times. Today, portobello mushrooms are widely available at farmers markets, specialty grocers and most supermarkets in North America, Europe, Asia, and Australia. They are one of the most cultivated mushrooms and make up about 90 percent of the mushroom production in the United States. Portobello mushrooms are available year-round.

Portobello mushrooms are a large, meaty mushroom with a rich, savory flavor, and dense, chewy texture. They easily grow to about 5 to 6 inches in diameter, with a brown color and firm texture. They are often served grilled, broiled, sautéed, stuffed, and as a meat substitute in sandwiches and burgers. They are sometimes hollowed out (removing the gills), and used as a pizza crust or bowl for other fillings. They can be chopped and added to soups and stews, baked into pasta and rice dishes, sliced and added to salads, and added to strudels and egg dishes. They are one of the most cultivated varieties of mushrooms and are favored by both professional and home chefs for their dense, meaty texture, and earthy flavor.

Nutrition and Health Benefits
Portobello mushrooms do have some room to brag when it comes to nutrition. They contain a lot of riboflavin, niacin, copper, selenium, pantothenic acid, phosphorus, potassium, manganese, fiber, thiamin, and folate. They also contain some protein, Vitamin B6, iron, zinc, magnesium, choline, and even a little Omega-6 and Omega-3 fatty acids. One cup of diced portobellos has all of 22 calories. They have a glycemic load of a mere 2, and a low glycemic index of 10. If you’re striving to keep your blood sugar under control, it would be hard to beat that!

Benefits for Diabetics. Mushrooms have many benefits for diabetics and those who may be prone to developing diabetes. Research has shown that eating a diet rich in vegetables, including mushrooms, may help to prevent gestational diabetes.

Mushrooms are high in B-vitamins, which have been shown to preserve mental function and ward off dementia in older adults and those with diabetes who take the drug metformin for blood sugar control.

Polysaccharides, a type of carbohydrate found in mushrooms, may have anti-diabetic properties. Animal studies have shown that polysaccharides may lower blood sugar levels, improve insulin resistance, and reduce pancreatic tissue damage. This may be at least partially due to the beta glucan found in mushrooms. Beta glucan is a type of soluble fiber that slows digestion and delays the absorption of sugars. This, in turn, controls blood sugar levels after a meal.

Polysaccharides may also reduce blood cholesterol levels, which helps reduce the risk of heart disease and stroke associated with uncontrolled diabetes.

Low Glycemic Index and Glycemic Load. The glycemic index and glycemic load are classification systems that help evaluate how carbohydrate-containing foods affect blood sugar. They have become a popular method used in the treatment of diseases such as diabetes.

The glycemic index ranks foods on a scale of 0 to 100. The ranking indicates how that food may affect your blood sugar levels after a meal. The rankings include a glycemic index of low (1 to 55), medium (56 to 69), and high (70 to 100). Foods with a low glycemic index will raise your blood sugar levels at a slower pace than those with a higher glycemic index score. Mushrooms have a glycemic index of 10 to 15, which is very low and means they won’t cause a spike in blood sugar levels.

The glycemic load system takes into account a food’s glycemic index in addition to its carbohydrate content and serving size. It is calculated by multiplying the glycemic index by the carbohydrate content of a specific serving size and dividing the result by 100. The glycemic load system classifies food into three categories: low (10 and under), medium (11 to 19), and high (20 and above). Foods with a low glycemic load will only slightly affect blood sugar levels, whereas those with a high glycemic load will cause a more significant effect on blood sugar levels. Mushrooms have a low glycemic load of less than 1 per cup. This means that they will not spike blood sugar levels after a meal.

Nutrient Density. Portobello mushrooms are a very nutrient dense food. This means that they are very low in calories in relation to the nutrients they contain. Because of this, portobellos can help with weight loss and weight management when used appropriately. For instance, portobellos can be used in place of meat in a sandwich, casserole, stew, or soup. This will reduce the calories, fat, and cholesterol per serving, while still providing a tasty and satisfying meal. Also, because they are so low in calories, you can eat more food without feeling like you have to deprive yourself to manage your weight. Focusing on nutrient dense foods, like mushrooms, helps to “crowd out” less healthful, more fat- and calorie-laden foods that can add pounds and make weight management difficult.

High in B-Vitamins. Portobello mushrooms are high in B-vitamins. These vitamins are used by the body in many ways. They can help to boost energy, cognition, and metabolism, while managing stress, the cardiovascular system, blood pressure, cholesterol levels, pre-menstrual syndrome, eye health, skin health, and more.

Low in Carbohydrates. Since portobellos are low in carbohydrates, yet provide some fiber, they can be appropriate for many types of diets, including a low-carbohydrate or keto plan, vegan, vegetarian, pescatarian, omnivore, Weight Watchers, South Beach, The Zone…you name it!

Reduced Cancer Risk. Diet and lifestyle choices can make all the difference when considering a person’s risk for cancer. For instance, research has shown that a very low intake of vegetables raises the risk for developing certain types of cancer.

In a study published in the March 2021 issue of Advances in Nutrition, researchers evaluated 17 studies involving over 19,000 adults to determine whether eating mushrooms is linked to reduced cancer risk. They found that higher mushroom consumption was associated with an overall lower risk of cancer, especially breast cancer. The benefit was seen regardless of the variety of mushrooms consumed, but the amount consumed made a difference. Those who ate about 1/8 to 1/4 cup (18 grams) daily had a 45 percent lower risk of developing cancer when compared with people who did not eat mushrooms.

Antioxidant Benefits. Mushrooms contain a lot of antioxidants. Selenium, which is plentiful in mushrooms, is a powerful antioxidant. It is believed to prevent cancer, cardiovascular disease, cognitive decline, and thyroid disease.

Mushrooms also contain high levels of glutathione and ergothioneine, two other antioxidants. They are believed to be essential for anti-aging, since they prevent cognitive decline and oxidative stress. Researchers have found that populations that consume a lot of these particular antioxidants have fewer neurodegenerative diseases. We only need to consume about five button mushrooms per day to reap the full benefits. Considering the fact that portobello mushrooms are the mature variety of button mushrooms, consuming one portobello a day may very well be enough to reap these benefits.

Potassium. Bananas are well-known for being high in potassium. However, one cup of cooked portobello mushrooms has more potassium than one medium-sized banana. Potassium is an essential electrolyte that is important for muscle contraction, and is helpful in workout recovery. Potassium is also linked to lower blood pressure, and protection from stoke, osteoporosis, and kidney stones.

How to Select Portobello Mushrooms
When shopping for portobello mushrooms, choose ones that are firm and solid. They should have tight gills. Dark and loose gills indicate age. Avoid those that look dried up, shriveled, slimy, or limp, since they are older and not the best choice. Mushrooms should smell fresh and earthy.

How to Store Portobello Mushrooms
For best quality, portobello mushrooms should be kept dry and unwashed in the refrigerator. Place them in a paper bag or wrap them in dry paper towels, then place them in the refrigerator where air can flow around them. Be sure not to place items on top of them, since that would damage the mushrooms. Use them within a week.

Do not wrap your mushrooms in plastic wrap or bags because that would cause moisture to accumulate, which would cause the mushrooms to spoil.

How to Prepare Portobello Mushrooms
When you are ready to use your mushrooms, you can wipe them off with a damp paper towel. They may also be rinsed under cool to warm water (just beware that this will make them slippery). The stems are edible, but many recipes call for removing the stems. This is because they can be woody and tough. If you remove them, save them for when you make stock. Next, gently scrape the bottom side of the cap with a teaspoon to remove the gills. The gills are edible, but can trap dirt. Also, they are dark in color and can make your dish a dull, dark, unappealing color. For these reasons, most resources recommend removing the gills. However, this is actually an optional step. Once the mushrooms have been cleaned off, and stems and gills removed (if desired), your mushroom caps are ready to be used in whatever way called for: sliced, diced, chopped, or left whole. However you prepare your mushrooms, it is advisable to cook them, even briefly, before eating them. Raw button, crimini, portobello, and other mushrooms contain toxins that can be harmful to health. Any type of cooking destroys the toxins, making them a very healthful food to eat.

How to Freeze Portobello Mushrooms
To freeze extra portobello mushrooms, first wash them well in warm water. For best results, they should be cooked in some way before being frozen. They may be sautéed in small batches for 5 or 6 minutes, steamed whole for 6 minutes, or sliced first and steamed for 4 minutes. After cooking the mushrooms, transfer them to a bowl of ice water to quickly cool them down. Drain them well, then transfer them an airtight freezer container. For best quality, frozen mushrooms should be used within one month.

Quick Ideas and Tips for Using Portobello Mushrooms
* Try a portobello sandwich with grilled portobello mushrooms, roasted red bell peppers, caramelized onions, fresh basil leaves, leafy greens (like arugula, baby greens, or Spring mix), mozzarella cheese, and a mustardy dressing.

* Most of the mushrooms we find in grocery stores are actually the same variety of mushroom. White button mushrooms are very young fungi. As they begin to mature, their flavor and appearance begin to change and they are then called crimini mushrooms, or baby bellas (baby portobello mushrooms). When they are fully mature, their flavor intensifies and they are then called portobello mushrooms. So, they are actually all one and the same fungi, but at different stages of development.

* If you have a recipe that calls for portobello mushrooms and you don’t have enough, you can substitute large crimini mushrooms (which are sometimes marketed as baby portobello mushrooms), or white button mushrooms. The flavor will be milder as you move from portobello to crimini to button mushrooms. But nevertheless, they may be used as substitutes.

* When you have extra mushrooms, store them in the refrigerator, but do not store them in airtight containers. Moisture will accumulate within the container and cause them to rot. Instead, store them in a paper bag or wrapped in paper towels. They need to be kept dry, and used within a week for the best quality.

* The stems of portobello mushrooms can be tough and woody. Many people remove any remaining stem before using their mushrooms. However, the stems are edible. If preferred, save them for making stock.

* To grill portobello mushrooms, remove any remaining stem from each cap. If desired, scrape off the gills with a spoon (note that this step if not mandatory). Brush both sides with oil of your choice. The caps may be marinated for up to 30 minutes before being grilled, if desired. Season as desired, then grill over medium-high heat for 5 to 7 minutes per side. Remove from the grill and enjoy!

* A simple way to add portobellos to a meal is to add some to your burgers. If they are meat-based burger, substitute half of the meat with chopped portobellos. If they are veggie burgers, simply add chopped portobellos to the mix, or substitute portobellos for half the beans called for in the recipe.

* If you’re watching your potassium intake, there is as much potassium in a 2/3 cup serving of cooked portobello mushrooms as there is in a medium banana.

* It is advisable to cook mushrooms before eating them. Try not to eat them raw. Most mushrooms contain traces of a compound, agaritine, that may be carcinogenic when metabolized into hydrazine compounds. There is conflicting evidence about this, but why take a chance? Agaritine is heat-sensitive. Cooking in any way, even briefly, destroys this compound, making mushrooms an extremely healthful part of any diet.

* Mushrooms are very porous. When marinading them, a shorter time is better than a longer time because soaking them for an extended period of time may cause them to be mushy. Marinading them for about 30 minutes is usually enough to do the job.

Herbs and Spices That Go Well with Portobello Mushrooms
Basil, cayenne, chervil, chili pepper flakes, chili powder, cilantro, dill, marjoram, mint, mustard (seed or powder), oregano, paprika, parsley, pepper, rosemary, salt, tarragon, thyme

Foods That Go Well with Portobello Mushrooms
Proteins, Legumes, Nuts, Seeds: Almonds, bacon, beans (in general), beef, chicken, chickpeas, eggs, fish (and other seafood), ham, hazelnuts, pine nuts, pistachios, sesame seeds, tofu, veal, walnuts

Vegetables: Arugula, asparagus, bell peppers, broccoli, celery, chard, chiles, chives, eggplant, endive, escarole, fennel, garlic, ginger, greens (all types), leeks, mushrooms (all other types), onions, parsnips, potatoes, scallions, shallots, spinach, squash (summer and winter), tomatoes (fresh, paste, sun-dried, and sauce), watercress, zucchini

Fruits: Lemons, olives, oranges, pears

Grains and Grain Products: Barley, breadcrumbs, buns (and bread of all types), couscous, focaccia bread, millet, pasta, polenta, rice (esp. basmati, brown), tortillas

Dairy and Non-Dairy Products: Butter, cheese (esp. cheddar, Jack, feta, goat, Gorgonzola, Gouda, mozzarella, Parmesan, provolone, ricotta, Swiss), cream

Other Foods: Mustard (prepared), oil (i.e., grapeseed, nut, olive, sesame, truffle, walnut), soy sauce, stock, tamari, vinegar (i.e., balsamic, red wine, sherry), wine (i.e., dry white and Madeira)

Portobello mushrooms have been used in the following cuisines and dishes…
Bruschetta, crepes, omelets, fajitas, focaccia, gravies, Italian cuisine, mousses, pasta dishes, pâtés, pizza, quesadillas, salads, sandwiches, sauces, soups, mushroom steaks, stews, stir-fries, stuffed mushrooms, tacos, veggie burgers

Suggested Food and Flavor Combos Using Portobello Mushrooms
Add portobello mushrooms to any of the following combinations…

Arugula + Balsamic Vinegar + Mozzarella + Rosemary
Arugula + Mustard
Arugula + Pasta + Peas
Arugula + Red Bell Peppers + White Beans
Balsamic Vinegar + Garlic + Olive Oil + Parsley
Barley + Thyme [Soups]
Bell Peppers + Eggplant + Goat Cheese [Sandwiches]
Breadcrumbs + Chives + Garlic + Olive Oil
Bitter Greens + Potatoes
Garlic + Ginger + Scallions
Garlic + Olive Oil + Parmesan Cheese + Spinach
Garlic + Soy Sauce
Garlic + Sun-Dried Tomatoes
Lemon Juice + Olive Oil + Parmesan Cheese + Thyme
Mint + Zucchini
Pesto + Polenta
Spinach + Tomatoes
Vinegar + Walnut Oil + Walnuts

Recipe Links
Grilled Portobello Mushrooms https://oursaltykitchen.com/grilled-portobello-mushrooms/#recipe

Veggie-Stuffed Portobellos https://www.cookingclarified.com/2017/03/how-to-season-to-taste/#zrdn-recipe-container

Sweet and Spicy Portobello Mushrooms https://mysolluna.com/2017/02/28/sweet-spicy-portobello-mushroom-recipe/

27 Delicious Portobello Mushroom Recipes for Dinner https://theinspiredhome.com/articles/31-portobello-mushroom-recipes#sweet-spicy

Vegetarian Portobello Mushroom and Avocado Burger https://www.thespruceeats.com/portobello-mushroom-burger-with-avocados-3378624

Meaty Broiled Portobello Mushrooms https://www.thespruceeats.com/broiled-portobello-mushrooms-2246699

Grilled Herb and Cheese Stuffed Mushrooms https://www.thespruceeats.com/cheese-and-herb-stuffed-mushrooms-336594

9 Ways to Use Portobello Mushrooms https://www.foodandwine.com/vegetables/mushrooms/portobello-mushroom/9-ways-use-portobello-mushrooms

Grilled Portobello Mushrooms https://www.wellplated.com/grilled-portobello-mushrooms/

Easy Portobello Mushroom Sauté https://www.allrecipes.com/recipe/88587/easy-portobello-mushroom-saute/

Roasted Portobello Mushrooms https://www.healthyseasonalrecipes.com/roasted-portobello-mushrooms/

Stuffed Portobello Mushrooms with Crispy Goat Cheese https://www.abeautifulplate.com/stuffed-portobello-mushrooms-with-crispy-goat-cheese/

Baked Portobello Mushroom Recipe (Vegetarian) https://detoxinista.com/baked-portobello-mushrooms-vegetarian-dinner/

Grilled Portobello Mushrooms https://www.jessicagavin.com/grilled-portobello-mushrooms/

Stuffed Portobello Mushrooms https://www.jocooks.com/recipes/stuffed-portobello-mushrooms/

Resources
https://www.onegreenplanet.org/vegan-food/tips-for-making-the-meaty-portobello-mushrooms/

https://www.livestrong.com/article/438060-how-to-store-and-freeze-portobello-mushrooms/

https://www.cookingclarified.com/2017/03/clean-portobello-mushrooms/

https://www.thekitchn.com/what-are-cremini-mushrooms-a-f-73949

https://specialtyproduce.com/produce/Portobello_Mushrooms_702.php

https://www.food.com/about/portobello-103

https://www.thespruceeats.com/what-are-portobello-mushrooms-5197534

https://nutritiondata.self.com/facts/vegetables-and-vegetable-products/2485/2

https://www.healthline.com/nutrition/mushrooms-good-for-diabetes#uses

https://www.livestrong.com/article/421447-portobello-mushroom-benefits/

https://draxe.com/nutrition/portobello-mushroom/

https://www.verywellhealth.com/mushrooms-lower-cancer-risk-5181032

https://pubmed.ncbi.nlm.nih.gov/33724299/

https://www.vegetariantimes.com/guides/4-plant-foods-you-should-cook-before-eating/

https://www.sciencedirect.com/science/article/abs/pii/S1756464610000241

https://www.bonappetit.com/trends/article/mushrooms

https://draxe.com/nutrition/portobello-mushroom/

https://www.eatingwell.com/article/9583/5-amazing-health-benefits-of-mushrooms/

https://www.seriouseats.com/knife-skills-how-to-prepare-portabella-mushrooms

Joachim, David. (2010) The Food Substitutions Bible. 2^nd Edition. Toronto, Ontario, Canada: Robert Rose, Inc.

Page, Karen. (2014) The Vegetarian Flavor Bible. New York, NY: Little, Brown and Company.

About Judi

Julia W. Klee (Judi) began her journey enjoying “all things food” in elementary school when she started preparing meals for her family. That love of food blossomed into a quest to learn more and more about health and wellness as related to nutrition. She went on to earn a BS Degree in Food and Nutrition, then an MS Degree in Nutrition. She has taught nutrition and related courses at the college level to pre-nursing and exercise science students. Her hunger to learn didn’t stop upon graduation from college. She continues to research on a regular basis about nutrition as it relates to health. Her hope is to help as many people as possible to enjoy foods that promote health and wellness.