Nutrition Notes
Often considered a vegetable, tomatoes are actually a fruit. Tomatoes come in a range of sizes and colours but they all have one thing in common: they're nutrient powerhouses. They're low in calories, packed with vitamins and minerals and are an excellent source of disease-fighting antioxidants.
Tomatoes and tomato products are one of the best dietary sources of lycopene, a potent antioxidant with cancer-fighting potential. Studies in the lab suggest lycopene helps protect against prostate, colorectal, breast and pancreatic cancers.
Heat processed tomato products such as stewed tomatoes and tomato sauce are the very best sources of lycopene. That's because heat breaks down cell walls, releasing more lycopene and therefore making more of it available for the body to absorb. Serving tomatoes with oil, such as olive oil, also increases the bioavailability of lycopene.
Tomatoes have cardio-protective properties, too. One study found that women who ate at least 7 servings of tomato-based foods per week - versus less than 1.5 servings - were one-third as likely to be diagnosed with heart disease. It's thought that potassium, folate and vitamin B6 in tomatoes is responsible for their heart benefits.
A Food Guide serving of tomatoes, ½ cup (125 ml) or one-half a medium tomato, delivers a mere 17 calories almong with plenty of vitamins A, C and K as well as potassium.
Nutrient information per ½ cup (125 ml) diced tomatoes:
| Calories | 17 cal |
| Fat | 0.2 g |
| Protein | 0.8 g |
| Carbohydrate | 3.7 g |
| Fibre | 1.2 g |
| Beta-carotene | 427 ug |
| Vitamin C | 12.1 mg |
| Vitamin K | 7.5 ug |
| Potassium | 226 mg |
| Folate | 14.5 u |
Source: Canadian Nutrient File, 2007b
Varieties
Over 300 varieties of tomatoes are grown locally in Canada. Tomato varieties can be grouped into three categories:
Round
Commonly referred to as slicing or beefsteak, these tomatoes are medium to large globe-shaped tomatoes. They're good for both cooking and eating raw. Their large shape makes them ideal for slicing and adding to sandwiches or dicing and tossing in salads.
Roma or plum
Also known as Italian or Italian plum, these egg-shaped tomatoes are smaller and less juicy than round and beefsteak varieties. They have a more concentrated flavour and few seeds, making them ideal for canning and making tomato sauce. I also prefer to uses plum tomatoes for Greek salads and frittattas.
Heirloom
This category of tomatoes ranges in size, taste and colour and includes varieties that have been passed down through the generations from hundreds of farmers and gardeners around the world. They range in colour from red to pink, purple, green and yellow.
Buying
When purchasing fresh tomatoes, choose ones that are smooth with a shiny, unblemished skin. Fresh tomatoes should be firm, but give slightly to gentle pressure. Tomatoes should feel heavy for their size and be free of any signs of mold or bruising. Ripe tomatoes should have a slightly sweet fragrance, especially at the stem end.
An easy way to gauge the ripeness of a tomato is to look for a star-shaped marking on its bottom. This is a good indicator that the tomato has started its final ripening process and is close to its peak flavour.
Locally grown tomatoes in Canada are at their peak in mid to late summer, July to September.
If purchasing tomatoes for a recipe, keep in mind that 3 to 4 small tomatoes equals roughly 1 pound (454 g) and 1 medium tomato equals about 1 cup (250 ml) when diced.
Storing
Tomatoes should not be stored in the fridge. Cold temperatures dull their flavour and change their texture. Only when it's really hot, or when tomatoes are overripe, should they be kept in the fridge. Ideally, tomatoes should be stored at room temperature away from direct sunlight.
Storing tomatoes close to other ripe fruits and vegetables will affect how quickly they ripen. Bananas, apples and pears, for example, naturally release ethylene gas, a compound that quickens the ripening process of nearby fruits and vegetables, including tomatoes.
Preparing
Tomatoes don't require any preparation to be enjoyed. In fact, eating a tomato straight from the vine (if you're so lucky!) is one of the best ways to enjoy this summer jewel.
When preparing fresh tomatoes, slicing them from stem to end retains their juiciness better than if sliced crosswise.
To peel fresh tomatoes, immerse them in a pot of boiling water for 10 to 20 seconds. Then, immediately submerge in cold water and, when cool enough to handle, gently loosen the skin with the tip of a knife and gently peel away skin.
To stew tomatoes, place diced tomatoes in a saucepan and season with salt and pepper. Simmer, tightly covered, over low heat for 20 to 30 minutes, stirring occasionally. Stewed tomatoes make an excellent base for sauces, soups and stews.
Due to their natural high acidity, tomatoes can react with some cookware, including aluminum and copper, resulting in a bitter aftertaste. For best results, stick to non-reactive surfaces such as enamelware and stainless steel.
Eating
Whether you eat them straight from the vine, add them to soups and salads, or use them to make classic tomato-based dishes such as pasta sauce and ratatouille, there are endless ways to enjoy fresh tomatoes.
Tomatoes add flavour and nutrition to just about any meal. Their natural sweet flavour pairs especially well with savoury ingredients such as garlic, basil, tarragon, wine, cheese, vinegars and onions.
Healthy ways to enjoy
Breakfast
- Enjoy a hearty breakfast sandwich made with sliced tomatoes, chopped spinach and a poached egg on a whole wheat English muffin.
- Add chopped fresh tomatoes to omelets, frittatas and quiches.
Lunch
- Enjoy a light lunch by making a Greek salad. Combine diced tomatoes, cucumbers, red onions, olives, fresh oregano and crumbled feta cheese. Season with olive oil, red wine vinegar and pepper.
- Make homemade bruschetta by topping a sliced whole-wheat baguette with diced tomatoes, crushed garlic, olive oil and chopped basil. Broil until bread is crispy and tomatoes are hot. Enjoy warm or cold.
- Stuff whole tomatoes with your favourite rice or seafood salad for an easy and delicious lunch.
Dinner
- Make an effortless side dish by drizzling sliced tomatoes with balsamic vinegar, olive oil, sea salt and pepper.
- Try gazpacho, a cold Spanish-style soup made with fresh tomatoes, onions, cucumber and red peppers. Click here for a recipe.
- Quickly sauté onions and garlic in olive oil; add diced fresh tomatoes and cook until tomatoes are heated through. Toss with cooked whole-wheat pasta and shredded fresh basil. Serve warm or cold.
Snacks
- Sprinkle tomato wedges with sea salt and freshly ground black pepper for a simple and delicious snack.
- Top whole-grain crackers with a quartered tomato slice, season with salt, pepper and some fresh basil.
- Make your own salsa - combine equal parts diced fresh tomatoes, cucumbers and yellow peppers. Season to taste with olive oil, salt, pepper and a thinly sliced jalapeno pepper.
Did you know?
- The tomato originated in South America before being introduced to Europe and North America.
- Tomatoes used to be called "love apples" in the south of France and Italy. People believed the succulent red fruit had aphrodisiac properties.