Enlarge / Cell-cultivated chicken is made in the pictured tanks at the Eat Just office on July 27, 2023, in Alameda, Calif. (credit: Justin Sullivan/Getty Images)

Months in jail and thousands of dollars in fines and legal fees—those are the consequences Alabamians and Arizonans could soon face for selling cell-cultured meat products that could cut into the profits of ranchers, farmers, and meatpackers in each state.

State legislators from Florida to Arizona are seeking to ban meat grown from animal cells in labs, citing a “war on our ranching” and a need to protect the agriculture industry from efforts to reduce the consumption of animal protein, thereby reducing the high volume of climate-warming methane emissions the sector emits.

Agriculture accounts for about 11 percent of the country’s greenhouse gas emissions, according to federal data, with livestock such as cattle making up a quarter of those emissions, predominantly from their burps, which release methane—a potent greenhouse gas that’s roughly 80 times more effective at warming the atmosphere than carbon dioxide over 20 years. Globally, agriculture accounts for about 37 percent of methane emissions.

Enlarge (credit: Tanja Ivanova)

In the US, for orange juice to be labeled as such, it must be 90 percent sweet orange, or Citrus sinensis. Thus, citrus producers in the US have long planted 90 percent Citrus sinensis. But this cultivar is extremely susceptible to the bacteria that causes citrus greening disease, which has devastated the near-monocultural Florida crop. There is as yet no way to control the disease; the most effective way to deal with it would be to find citrus cultivars that are resistant to it and breed them with sweet orange to grant them disease resistance.

Sweet oranges are a hybrid of mandarin and pomelo and are not especially genetically diverse. Any disease-resistant citrus we know of, however, does not taste like sweet orange, so breeding with it will produce fruit and juice with off flavors. It has been difficult to define and quantify those off flavors, though, because it has been difficult to define and quantify the components essential for proper orange flavor.

Now, researchers at the USDA Agricultural Research Service performed a comprehensive chemical evaluation of 179 different citrus combinations—oranges, mandarins, and assorted hybrids—and cross-referenced their chemical compositions with evaluations of orange and mandarin flavors in juice samples performed by a “trained panel.”

Enlarge (credit: Bruce Yuanyue Bi)

A few years back, the Internet was abuzz with the idea of vertical farms running down the sides of urban towers, with the idea that growing crops where they're actually consumed could eliminate the carbon emissions involved with shipping plant products long distances. But lifecycle analysis of those systems, which require a lot of infrastructure and energy, suggest they'd have a hard time doing better than more traditional agriculture.

But those systems represent only a small fraction of urban agriculture as it's practiced. Most urban farming is a mix of local cooperative gardens and small-scale farms located within cities. And a lot less is known about the carbon footprint of this sort of farming. Now, a large international collaboration has worked with a number of these farms to get a handle on their emissions in order to compare those to large-scale agriculture.

The results suggest it's possible that urban farming can have a lower impact. But it requires choosing the right crops and a long-term commitment to sustainability.

Enlarge / Sisal is an invasive species that is also grown agriculturally. (credit: Chris Hellier)

Women and girls across much of the developing world lack access to menstrual products. This means that for at least a week or so every month, many girls don’t go to school, so they fall behind educationally and often never catch up economically. 

Many conventional menstrual products have traditionally been made of hydrogels made from toxic petrochemicals, so there has been a push to make them out of biomaterials. But this usually means cellulose from wood, which is in high demand for other purposes and isn’t readily available in many parts of the globe. So Alex Odundo found a way to solve both of these problems: making maxi pads out of sisal, a drought-tolerant agave plant that grows readily in semi-arid climates like his native Kenya.

Putting an invasive species to work

Sisal is an invasive plant in rural Kenya, where it is often planted as livestock fencing and feedstock. It doesn’t require fertilizer, and its leaves can be harvested all year long over a five- to seven-year span. Odundo and his partners in Manu Prakash’s lab at Stanford University developed a process to generate soft, absorbent material from the sisal leaves. It relies on treatment with dilute peroxyformic acid (1 percent) to increase its porosity, followed by washing in sodium hydroxide (4 percent) and then spinning in a tabletop blender to enhance porosity and make it softer. 

Enlarge (credit: Koval Nadiya)

There is no questioning our ongoing love affair with cheese. From pizza and pasta to that decadent slice of cheesecake, we can’t get enough. But the dairy industry that produces cheese has had a negative impact on our climate that is not exactly appetizing.

While plant-based alternatives to cheese are easier on the environment—not to mention ideal for those who are lactose intolerant (raises hand) or vegan—many of them are still not cheesy enough. Now, a team of scientists from the University of Copenhagen in Denmark has created nondairy cheese with a taste and texture that’s much closer to the real thing. Instead of developing some sort of futuristic technology, they harnessed the transformative power of a process that has been used to make traditional cheese for thousands of years—fermentation.

Just add bacteria

Why are plant-based cheeses so notoriously difficult to make? Not all proteins are created equal. Because plant proteins behave so differently from milk proteins, manufacturers rely on coconut oil, starch, or gums as hardening agents and then add colors and flavors that give the finished product some semblance of cheese.