Tag Archives: Science

Overview: Rotary vs. Vibratory Pumps

In The Great Espresso Machine Wars of 2011, the bloodiest battle was that between the rotary and the vibratory pump. Seriously; things got real.

You didn’t hear about it? Well, it’s really not something we like to rehash — and there were definitely lessons in there for all of us. But even though we’re not yet prepared to talk through it (too soon!), we don’t mind taking a couple of pumps apart and asking one of our favorite engineers for his input on how these bad boys work.

Watch as Gail and Bill Crossland go through the internals of a vibratory and rotary pump, discussing how they work, why you might select one over the other and what to expect from them. Then we measure the sound differential between the vibratory pump on the Rocket Espresso Premium Plus and the rotary pump on the Rocket Espresso Evoluzione to learn if the whole ‘it’s quieter!’ argument really holds water. Finally, we pull shots to see if there is a noticeable, practical difference in flavor between the two styles of machines.

Back to the Roots: Putting coffee grounds to work

What do you do with your coffee grounds?  Compost them, toss them in the garbage, leave them in your knock box and forget about them until you get yelled at by your house mate? Don’t do the latter, mold is a serious health concern, people. ;)

Co-founders Alejandro Velez and Nikhil Arora put recycled coffee grounds to work every day at their company Back to the Roots. The pair met at UC Berkley, and were inspired by a lecture that discussed the potential to grow gourmet mushrooms entirely on recycled coffee grounds. Sparked by this fun fact and a little entrepreneurial spirit, they started growing mushrooms in a bucket of used grounds, and eventually developed mushroom growing kits that you can use in the comfort of your home.

The kit comes with a cardboard carrier, bag of recycled coffee grounds, mushroom spores and a water mister.  With a little TLC (mist the bag twice a day) and in as few as 10 days, you can harvest your first batch of oyster mushrooms and most kits yield at least two crops.

Check out my first batch after 14 days. These mushrooms ended up on my plate sautéed with garlic, olive oil, chili flakes and tossed with angel hair pasta. Delicious!

Back to the Roots is on track to recycle 3.6 million pounds of coffee grounds from Peet’s Coffee and Tea in 2012, and help families grow over 135,000 pounds of fresh food in their own homes. Sustainability + yummy mushrooms = many happy tummies. I bet you’re going to think twice before tossing out your coffee grounds now – am I right?

Health Watch: Coffee May Contribute to a Longer Life

And a happier one, too! If you need more scientific data to support your java love, read on.

Studies have shown that men and women who are drinking six or more cups of coffee a day have a 10 (for men) and 15 (for women) percent lower risk of dying at an earlier age.

Historically, doctors have noted a correlation between caffeine and an increase in bad cholesterol, high blood pressure and the risk of heart disease; however, a recent study has revealed an interesting pattern: Drinking coffee may extend the overall lifespan in already healthy individuals.

A study held from 1995 to 2008 involving the National Institutes of Health and AARP members between the ages of 50 to 71 from all over the US has given researchers a better look at the possible health benefits of coffee. They made sure to exclude people who already had heart disease, a stroke or cancer or had too many or too few calories a day.

‘By 2008 about 52,000 had died. Compared to those who drank no coffee, men who had two or three cups a day were 10 percent less likely to die at any age. For women, it was 13 percent,’ revealed the study.

Since previous studies have suggested that coffee may have a part in heart disease, this study inspired Neal Freedman, nutritional epidemiology researcher at the National Cancer Institute, to consider another contributing factor. He noted that many who were at higher risk of death were coffee drinkers and tobacco smokers, too. ‘It was only after we took into account people’s smoking that the association, the inverse association, revealed itself,’ he said. ‘Smoking has a really strong association with death.’

In the end, Freedman’s study showed that those with healthy habits who drink six or more cups of  caffeinated or decaffeinated coffee did cut the risk of dying but not to the extreme. Freedman couldn’t calculate the exact amount of extra life each cup can give you. However, he admits coffee drinkers were less likely to die from heart or respiratory disease, stroke, diabetes, injuries, accidents and infections. No effect was seen on cancer death risk, though.

So we’ll admit that we’ll grab that extra cup of java to increase the longevity of our lives, even if it’s only by a few percentage points, but a word of advice: More coffee does not mean you should pack on the sugar and cream.

As Dr. Frank Hu of the Harvard School of Public Health advises, ‘Watch the sugar and cream. Extra calories and fat could negate any benefits from coffee.’

Health Watch: Java not to Blame for Sleepless Babies

Coffee was what kept me up during those late nights of studying in college; for expecting and new mothers, you’d think it would be their lifeline too! I figured caffeine was the fuel that helped them during long, sleepless nights with their newborns.

But to my surprise, drinking caffeine has been a concern for many mothers. It’s been believed that mothers should cut down on their coffee habit because of adverse affects that could affect the sleeping patterns of their bundles of joy. However, researches have found that coffee does not affect your child’s sleeping habits.

This doesn’t necessarily mean you can keep drinking that Grande Double Mocha you crave each morning, but studies have failed to show any heightened risk correlating between a mother’s caffeine intake and sleeplessness in her child.

Heavy coffee drinkers are defined as consuming about 300 milligrams or more of caffeine per day via coffee or any caffeinated beverage. “In 2010, the American College of Obstetricians and Gynecologists (ACOG) said that 200 milligrams of caffeine a day –  about the amount in a 12-ounce cup of coffee — probably did not carry pregnancy risks.”

In an article in HealthDay, Brazilian researchers conducted an analysis of sleeping patterns of more than 4,200 infants until the age of 3 months. The mothers of these infants had light caffeine consumption before and after delivery. Led by Dr. Ina Santos of the Federal University of Pelotas in Brazil, the study was designed to analyze the possibility that caffeine linked to disrupted sleeping patterns in newborns and babies. Of the 4,200 babies, 885 mothers were interviewed after delivery and three months later to gauge their caffeine-drinking habits. Each baby was then examined after delivery and had follow-up exams three months later. Santos and her colleagues stated that all but one mother consumed caffeinated beverages.

Twenty percent of the mothers were considered to be heavy consumers and 14 percent had heavier caffeine consumption three months after giving birth. About 14 percent of the babies frequently woke up during the night. There was some indication that nighttime wake-ups were more prevalent with babies whose mothers were heavy caffeine drinkers during pregnancy and nursing, but Santos claims these numbers were still not significant.

‘Nighttime wakening among babies that age can be due to so many different things,’ Lona Sandon, a registered dietitian and assistant professor of clinical nutrition at the University of Texas Southwestern in Dallas said. ‘So to tease out caffeine’s role is going to be very difficult.’

Caffeine can cause sleep disruption among adults, but researchers aren’t finding any hard evidence that java consumption, at any particular level, is directly connected to the sleep pattern disruptions of babies.

Compare: Chemex Filters vs. Hario 02 Filters

Our first time out, Allison used a Hario 02 paper filter for her brew test with the Chemex. And we didn’t hear the end of it from our YouTube fans!

So once we received our first shipment of signature Chemex filters, we decided to do a side by side brew comparison to practically determine if you could tell a difference in the cup. Watch as Allison brews up two batches on the Chemex and we taste them to find out.

Experimenting with Cold Brew Coffee

Do you really need a fancy, specially-designed gadget to brew up a batch of cold coffee? Or can you just use your trusty ol’ press pot? While we carry a couple of different cold brew options (from Hario and Sowden), we wanted to see if using one of them (namely, the Sowden) produced a better, worse or similar cup to making a cold brew with a La Cafetiere french press.

So we put Allison to the test! Watch as we brew up a batch in each, using the same grind and coffee-to-water ratios, allowing them to sit over night and then giving them a taste test. We also compare how much sediment appears in the cup. So exciting!

SCG’s Great Stovetop Experiments

There is nothing quite like taking a random suggestion and putting it to the test! During our original stovetop prep video, Rade mentioned using sparkling water to achieve some form of crema from the espresso and we also received a viewer suggestion that using preheated water produced a better cup.

We asked him to put these two ideas to the test to determine if either results in a noticeably improved cup. Hilarity ensued.

Testing Freezer-Stored Coffee Beans – Redux

Awhile ago, we stored some beans in their original roaster bags in the freezer, then we pulled shots with them. The taste of freezer burn was so distinct, however, it was hard for us to recommend folks store their coffee this way. That video raised that hackles of many a folk (which we were very surprised to hear!) and we received a lot of feedback regarding ways in which they stored their beans in the freezer to ensure they still retained good flavor. So we tried three different variations recommended, two different freezers and two different grinders to see if any of them provided good results.

Watch as Gail goes through testing these different storage methods.

Testing Freezer-Stored Coffee Beans

One of the most frequent questions that we’re asked is regarding how to best store coffee beans in order to keep them fresh. We have done several videos testing how beans hold up over time in their roast bags or a container such as the Airscape, but how about the oft-recommended freezer storage? How do beans perform after being frozen?

We put a couple of bags in the freezer back in October 2010 and then pulled them out of the vault three months later. Watch as Gail pulls shots using one bag that was completely sealed and another bag that was opened and then folded closed using the bag’s tabs.