Homemade Tomato Sauce and the Benefits of Lycopene

Homemade Tomato Sauce

It’s tomato harvest time here in my backyard, and as my mom says, we are up to our earballs.  Each year at the beginning of September, I go through the same process of frantically calling upon friends and neighbors to please come with large bowls and take some home to enjoy. I also repeat the same ritual of attempting to make a large pot of sauce so I can preserve some of the garden goodness for the months ahead, but always with mixed results.  This year, however, I decided to stop cutting corners and do it right: I grew more romas than slicers or cherry tomatoes, and went through and blanched, skinned, and seeded the tomatoes before putting them in the pot. I always cringe at the thought of getting rid of so much of each precious tomato, but it yielded a thick sauce free of skins and seeds that is worth sticking in the freezer for a colder month.

Because I love to get the most nutrition possible out of my food, I am always wary of any process that involves taking out a significant portion of the food (like skins and seeds) and then cooking it for many hours, so making sauce seems a bit antithetical to this principle.  However, in this case, this food processing can actually boost the benefit of the food because of a little molecule called lycopene.  Lycopene is a carotenoid, or substance that gives the tomato its red color.  It is also found in other pink fruits such as watermelon, papaya, and guava, but the highest amount in the western diet is found in tomatoes.   

In the body, lycopene acts as a powerful antioxidant, meaning it gives electrons to oxygen or other molecules that are missing an electron.  Without an antioxidant these molecules then “steal” electrons from places like our DNA or cell membranes, causing damage to the tissues.  Lycopene has been shown to be a more effective antioxidant than Vitamin E or beta carotene, and can help to prevent cancer of the liver, lung, prostate, breast, and colon.  In cancer cells, it can arrest cells growth and promote cell death while having no effect on normal cells.  It also has been shown to prevent inflammatory disease of the liver, heart and neurological systems.

Interestingly, there are two ways in which cooking helps boost the benefits of lycopene.  First, by cooking out the water, the lycopene content becomes more concentrated, so you get more of it in each bite.  For instance, in a raw tomato, you may get as little as 8.8 mcg/g of lycopene, whereas in tomato sauce, you may get as much as 131 mcg/g. Powdering and freeze drying tend to decrease the amount of lycopene and makes it very unstable, whereas freezing and heat processing stabilizes the lycopene. Also, there are two molecular forms of lycopene, called trans and cis.  In a raw tomato, lycopene is in the trans form, while heat processing converts the lycopene to a cis form.  The longer the cooking, the more of this conversion takes place.  This cis form is more “bioavailable” to the body, meaning it is easier for it to utilize.

One other important thing to note is that how the tomatoes are grown also makes a difference.  Conventionally grown tomatoes have been found to be lower in many nutrients, including Vitamin C, polyphenols, quercetin, and flavonoids like lycopene.  So looking for tomatoes that have been organically grown or growing your own will yield a sauce richest in this health-promoting substance.  Plus, it will be the best sauce you’ve ever tasted.  

Enjoy!

Tomato sauce from scratch:

This is not a quick recipe, but it is a great way to use the bounty of your garden and you will never get a sauce from a jar that tastes as good as this!

Yield: 3-4 quarts

8 pounds fresh roma tomatoes

½ cup red wine

2 Tbsp olive oil

1 yellow onion, diced

5 garlic cloves, minced

2 stalks of celery, diced

2 tsp dried basil

1 tsp dried oregano

½ tsp black pepper

1 Tbsp kosher salt

1 heel of parmesan (optional)

1 small can tomato paste (optional)

Fill a large pot with water and bring to a boil.  Put the tomatoes in (as many at a time as you can fit) and let them sit 2-3 minutes, until you can see the skin starting to crack on a few of them).  Strain the tomatoes out and put in a large bowl, repeat until all the tomatoes are done.  Empty the pot.  With each tomato. make a small slit in the skin and “pop” the insides out.  Cut this in half and gently squeeze out the seeds.  Place the skinned and seeded tomato in the pot.  Repeat until all the tomatoes are done. Add the rest of the ingredients except the tomato paste to the soup pot. Cover and bring to a simmer over medium high heat. Reduce heat and continue to simmer, about an hour.  At this point, you can take a potato masher and break up the tomatoes a bit more.  Continue to simmer uncovered until the sauce thickens, about 2 hours more. If you want to add some extra lycopene and give the sauce a bit more heft, you can add the tomato paste for the last hour of cooking.  Serve with pasta and homemade meatballs.

Sources:

Hallmann E., Orv Hetil. The influence of organic and conventional cultivation systems on the nutritional value and content of bioactive compounds in selected tomato types.J Sci Food Agric. 2012 Nov;92(14):2840-8. doi: 10.1002/jsfa.5617. Epub 2012 Feb 20.

Györéné KG, Varga A, Lugasi A. A comparison of chemical composition and nutritional value of organically and conventionally grown plant derived foods. 2006 Oct 29;147(43):2081-90.

Shi J, Le Maguer M.   Lycopene in tomatoes: chemical and physical properties affected by food processing. Crit Rev Biotechnol. 2000;20(4):293-334.

Unlu NZ, Bohn T, Francis DM, Nagaraja HN, Clinton SK, Schwartz SJ. Lycopene from heat-induced cis-isomer-rich tomato sauce is more bioavailable than from all-trans-rich tomato sauce in human subjects. Br J Nutr.  2007 Jul;98(1):140-6. Epub 2007 Mar 29.

Trejo-Solís C, Pedraza-Chaverrí J, Torres-Ramos M, Jiménez-Farfán D, Cruz Salgado A, Serrano-García N, Osorio-Rico L, Sotelo  Multiple molecular and cellular mechanisms of action of lycopene in cancer inhibition. J.Evid Based Complement Alternat Med. 2013;2013:705121. doi: 10.1155/2013/705121. Epub 2013 Jul 21.

Lycopene. Wikipedia.