Tofu and Soy Milk

What do tofu and soy milk have to do with each other?  What do cheese and cow milk have to do with each other?  You've got it!

History: Soy milk probably predates tofu, per the historic record.  Evidence of the first soy milk dates back to the first century CE, in China.  Tofu was made starting just a few hundred years later, during the Han Dynasty, also of course in China.

Processing: It's quite simple to make soy milk.  First, you dry soybeans.  Then you either grind them into flour and add water, or just add the water and grind the whole beans into the water.  This mixture can be adjusted until the proportions of fat and protein are about the same as those found in regular milk.  Most of the tofu that is eaten, especially in this country, is simply made by adding a coagulant (most commonly gypsum) to soy milk.  This is identical to the process of, say, making cottage cheese.  The resultant curds are pressed and there you have it, tofu!  Tofu "skin" is made by boiling the soy milk and collecting the stuff that coagulates at the surface.

Health Information: Tofu and soy milk maintain pretty much all of the health benefits of whole edamame, except that the fiber is lost.  Ounce for ounce, these processed products have more protein, and more fat.  The usual fat content of soy milk is 2%, which is the same as reduced-fat cow's milk.  So what about those heart-healthy claims?  In 1995, a meta-analysis of 29 studies by J.W. Anderson et al., published in the New England Journal of Medicine, found that a diet heavy in soy protein decreased total cholesterol, LDL, and triglycerides.  This paved the way for an FDA-approved "heart-healthy" claim from 1999 onwards.  However, as is often the case in these sort of things, another review of studies by F.M. Sacks and colleagues, 10 years later, did not find anywhere near as high of a benefit as the prior studies had.  In fact they found that you needed a diet where half the protein came from soy, and then you only got about a 3% reduction in LDL. 

Sustainability: Here's one misconception - legumes such as soy beans only replenish the nitrogen in the soil if they are plowed under.  So the harvest of soy leads to nitrogen depletion, which leads to heavy fertilizer use and as already mentioned, heavy pesticide use.  But, the balance of soy milk versus cow's milk definitely favors the vegetable product, in terms of the resources needed and used.

Where to Find: Anywhere.

Relevant Blog: Organic Health Blog: The link is to a well-commented post on soy milk.

Bottom Line: This products have been around for a long time and are standard fare for a vegetarian trying to get their protein.  Use in moderation while the science continues to be inconclusive.

References:
1. Wikipedia
2. Tofu nutrition facts
3. Image of Mapo Tofu from Flickr Creative Commons

Top Twenty Tuesday #9: Soybeans (Glycine max)

Having grown up in Iowa, I consider myself an expert in recognizing two crops: corn, and soy.  If you don't know what I'm talking about, drive yourself through Iowa the next time you take a cross-country trip.  If you do know what I'm talking about, you also know that none of that soy every made it to the plate, at least not in unaltered form.  Where did all this soy come from?

History: Soy beans are native to eastern Asia, which makes a lot of sense considering how many soy-based foods are Asian.  For the first 3,000 of the approximately 5,000 years that soy has been under cultivation, it was not eaten at all, but considered a sacred crop that renewed the soil.  Some of the first recorded consumption of soy goes back about 2,000 years, in China.  Soy made its move out of China in the 15th and 16th centuries, and was introduced to the future United States in 1765, to be used for hay.  People only really began eating soy in quantity outside Asia from the 1920's onwards.

Worldwide Production: 220.5 million tons, of which 4.4 million tons, or about 1.5 pounds for every man, woman, and child, is eaten by humans per year.

Growing: More than half of the soybeans in the world are now grown in non-native territory, with Iowa leading the pack, growing about 75 million tons of soybeans per year.  Partly due to this non-native status, soy is afflicted by a variety of diseases.  The solution to this, as you might already know, has been genetic modification and extremely heavy use of pesticides.  As of 2006, 89% of the US crop was genetically modified.  Organic, non-GMO soy is available but the truth is that humans eat hardly any of the soy grown (see below).

Harvesting: Fully automated.

Eating and Processing: I'm going to spend the rest of the week exploring some soy-based products.  But you should know what happens to the majority of soy.  The mature seeds are cracked open and rolled into flakes, and then bathed in the industrial solvent hexane.  This has the effect of removing the oil, which makes up about 20% of the seed.  The remainder is almost all protein, and is fed to animals, along with the husks.  This is the backbone of the intensive factories that grow chickens, pigs, turkeys, and some fish.  This is the fate of 98% of the soy grown in the United States.  You can eat and enjoy immature soybeans - they're called edamame!

Health Information: I'll focus on edamame, the only "whole" soy product you're every likely to eat.  One cup of edamame has eight grams of fiber (1/3 of the RDA) and eight grams of fat.  2.8 grams of that fat is omega-6, and 560mg is omega-3.  Then there's the protein, 1/3 of a day's worth and fairly complete, at that.  There's also a nice mix of vitamins and minerals, with quite a bit of folate (121% RDA), manganese (79% RDA), and vitamin K (52%).  Soy also has phytoestrogens, of course - most notably genistein and daidzein.  So does eating soy increase of decrease the risk of breast cancer?  That, my friends, is a subject in of itself and I intend to post on it soon.

Sustainability: Well okay, here are the two biggest issues: the spread of GMO soy, and the cutting down of the Brazilian rainforest to grow more soy.  "Roundup-Ready" soy, from Monsanto, has been available since 1995 and has essentially completely taken over the American market.  The result, just 15 years later, is the rise of superweeds resistant to Roundup.  You can backlash against this through your tofu purchasing as much as you want, but the only real solution to reducing the amount of GMO soy and the slash-and-burn the rainforest is to reduce the amount of meat you consume.  That's it.

Bottom Line: If you're going basic, enjoy your edamame.  Check back throughout the week to learn about other soy products!

References:
1. Wikipedia
2. Edamame nutrition facts
3. Image of an edamame stuffed animal (?) from Flickr Creative Commons

GEM #10: Eat Locally, Think Globally

Yeah, it's pretty cliched, but I've turned the saying around, somewhat.  Search the internet and you will find many articles about thinking globally and eating locally, with the emphasis on the latter.  Eating locally is incredibly important, and despite a diet of mostly carrots, parsnips, potatoes, beets, and turnips Sarah and I are surviving pretty nicely. 

But let's be realistic - if you are going to eat rice, or coffee, or soy sauce, or Pacific salmon, you are a global eater and you need to think like one. I try to talk about food miles and other relevant things like that when I can, but the real global statistic of interest is how much of a certain food is actually produced/caught and consumed.  Which is why I've added a new section "Worldwide Production" to my posts over the last couple of months.  Besides being informative, it's fun to think about how food is divvied up across the six billion (and growing) individuals that make up the human component of this world.

This week I'm going to debut a new side column so that you can quickly and easily see how much of a particular food is produced in a given year.  Most of this information is from FAO-STAT.

Relevant Article: This is from the Boston Globe, way back in 2004.

Image: The temporary "Victory Garden" in front of SF City Hall, 2008.

Tiger Prawns (Penaeus monodon)

I was reviewing my posts the other day and realized that I've never written about shrimp, which is a food I definitely enjoy on occasion.  I still remember the first time I had crispy whole fried shrimp at Chau Chow in Boston's Chinatown (not a food for the fainthearted...).  Whether intentionally or not I've surely had tiger prawns. 

History: Tiger prawns, also known as giant, jumbo, and black tiger prawns, are one of the larger members of the shrimp family, and are native to the Indian Ocean and the western Pacific Ocean.  They have been a staple of Indian and Southeast Asian cuisine for some time and continue to be most popular in Southeast Asia.  Currently, more than two-thirds of the annual consumption is from farmed shrimp.

Worldwide Production: 900,00 thousand tons: that's 4.5 average-sized (30 grams) shrimp for every man, woman, and child in the world, per year.

Growing: Tiger prawns are considered to be marketable when they have reached 30 grams in size.  In the wild, a full grown prawn can be more than one-foot long and weight up to 650 grams!  They are carnivores and must be fed animal matter, as such, when they are raised in captivity.

Eating and Processing: The majority of tiger prawns meet the fate of most shrimp: frozen and shipped abroad.  They are prepared in much the way that any large shrimp is.
Health Information: Shrimp as a whole are known to be very high in cholesterol and are thus commonly on the "avoid" list for those with high cholesterol.  That being said, is there data that eating this high cholesterol food will actually raise your cholesterol?  Limited evidence says that the opposite is true.  For example, rats fed shrimp shells had improvement in their lipid profiles.  A diet heavy with shrimp, squid, and octopus lowered the lipid profile of mice.  Food for thought, indeed.  A three ounce serving of shrimp also has half of the daily RDA of selenium, and more than one-third of protein. 

Sustainability: There are quite a few issues with tiger prawns.  These complaints are well laid out in the book Bottomfeeder, by Taras Grescoe.  To summarize, the shrimp farms are contaminated with chemicals, and are not "self-contained" systems and thus contaminate their surroundings.  By some measures shrimp farms, which have decimated the mangroves lining Bangladesh, can even be blamed for misery and death resulting from the failure of natural flood barriers.  Trawling for wild tiger prawns is no better, and is responsible for a grotesque level of bycatch.  Seafood Watch gives farmed and wild-caught tiger prawns an AVOID rating at this time.

Where to Find: Why should I tell you when you should really be avoiding this shrimp?!

Relevant Blog: CleanFish: If and when the tiger prawn industry becomes sustainable, perhaps these folks will make them available. 

Bottom Line: Know about tiger prawns but don't eat them, at least not now.

References:
1. Wikipedia
2. Shrimp nutrition facts
3. Seafood Watch Report Card
4. Image from Flickr Creative Commons

Heirloom Thursday: Meyer Lemons

It wasn't so long ago that I wrote about lemons, but given how many Meyer lemons I've been seeing in the stores recently, I figured it's time to revisit them.

History: Guess what?  The Meyer lemon isn't a lemon, it's actually a cross between a lemon and an orange.  As such, it's technically a cross (Citrus x meyeri).  This was originally brought to the attention of the world by Frank Nicholas Meyer, who brought it from China to the United States in 1908.  These sweet lemons became very popular in California but were found to harbor a virus implicated in widespread citrus destruction.  As a result, most Meyer lemon trees were destroyed in the 1940's.  It wasn't until 1975 that the "improved" Meyer lemon was released by the University of California, and this is lemon that Alice Waters and others have popularized.

Worldwide Production: Hard to say, as many are grown in backyards and others might not be counted separately from lemons in general.
Growing: Meyer lemons are winter crops that enjoy warm climates, and California and Texas seem to be their favorite spots.

Eating and Processing: They are definitely still lemons, but not nearly as acidic as a typical lemon.  As such they can be eaten out-of-hand or, more usually, as a cooked part of a dish or a condiment.  The skin is also edible.

Health Information: If you manage to eat a whole medium sized lemon, you will get 140% of your day's vitamin C, 20% of your daily fiber, and a smidgen of other vitamins and minerals. Lemons are of course very acidic, with a pH ranging from 1.8 to 2.3, which is just a bit more acidic than the human stomach. This doesn't mean so much for most people except those sensitive to acid (including those on acid-suppressing meds).  And Meyers are less acidic than normal lemons.

Where to Find: If you live near them, as I used to, they are hard to miss at their peak abundance.  In other parts of the country it's a bit more hit-or-miss.  Right now is the time to find them in places like Whole Foods.

Relevant Blog: Cannelle et Vanille: This blog, by Aran, has clearly a huge readership and for good reason - her photos are amazing!  Check out this very recent post on Meyer lemons with some very mouth-watering pictures.

Bottom Line: Get yourself some Meyer lemons this week and get creative!

References:
1. Wikipedia
2. Lemon nutrition facts from Nutrition Data.com
3. Image of Meyer Lemons from Flickr Creative Commons

Book Review: Food Rules: An Eater's Manual

By now, many of you have probably read Michael Pollan's newest book, Food Rules.  This isn't really a book but a pamphlet, which contains sixty-four rules in a mere 140 pages, half of which are illustrations.  These rules on what to eat and how to eat it, spring partly from Pollan's head and partly from solicited advice from his legions of fans, many through the New York Times "Well" blog.

I have really enjoyed Pollan's other works, and was a bit disappointed at the brevity of this book.  He points out that, in his opinion, good healthy eating is actually pretty simple and doesn't need a whole book to explain.  However his own previous books put the test to that, and I have to say that healthy eating is not a simple matter.

I've been writing this blog and thinking about food quite a bit almost a year and a half, and I feel that while I've scratched the surface, I certaintly haven't dug a nice furrow for fertile plantings.  In other words, what to eat and why to eat it are not simple questions that can be thoroughly explained in such a short format.

However, it is true that if you follow his rules more or less to the letter, your diet will be much better.  And I did get reminded of some good fundamental ideas (e.g. if you snack, only snack on fresh fruits, vegetables, and nuts) that can definitely lead to healthier living.  Do you need this book on your shelf?  If you already have his other books (I especially recommend The Omnivore's Dilemma) maybe not.  If you are a Pollan novice, it's a nice summary of his thoughts.

Relevant Website: Michael Pollan's Official Website

Top Twenty Tuesday #8: "Vegetables"

The astute amongst you will note that I skipped number nine, and this was done with good reason.  I was working in the hospital all weekend so need a "freebie" this week.  And here it is: number eight is "vegetables NES."  NES stands for "not elsewhere specified" which is a familiar catch-all to the medical field, where we make frequent use of NOS - "not otherwise specified."  So people do eat vegetables, but I can't tell you exactly what kind.  Back to #9 next week, I promise.

Worldwide Production: 245 million tons: that's 82 pounds of "vegetables" for every man, woman, and child in the world, per year.

Relevant Blog: A Veggie Venture: There are so many vegetarian and vegan blogs out there, this is just one of many, by Alanna Kellogg.