Children’s Dislike of Cauliflower, Broccoli could be Written in Their Microbiome

From the ACS Press Room

Children’s Dislike of Cauliflower, Broccoli could be Written in Their Microbiome

“In-Mouth Volatile Production from Brassica Vegetables (Cauliflower) and Associations with Liking in an Adult/Child Cohort”

Journal of Agricultural and Food Chemis-

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Many children, as well as adults, dislike Brassica vegetables, such as broccoli, cauliflower, cabbage and Brussels sprouts. In the mouth, enzymes from these vegetables and from bacteria in saliva can produce unpleasant, sulfurous odors. Now, researchers reporting in ACS’ Journal of Agricultural and Food Chemistry have found that levels of these volatile compounds are similar in

parent-child pairs, suggesting shared oral microbiomes. They also found that high levels cause children to dislike the vegetables.

Brassica vegetables contain a compound called S-methyl-ʟ-cysteine sulfoxide that

produces potent, sulfurous odors when acted upon by an enzyme in the plant’s tissues, as well as by the same enzyme produced by bacteria in some people’s oral microbiomes. Previous studies have shown that adults have different levels of this enzyme in their saliva, but whether children also have different levels, and whether this influences their food preferences, is unknown. Damian Frank and colleagues, who conducted this research at CSIRO, Australia’s national science agency, wanted to investigate differences in sulfur volatile production in saliva from children and adults and analyze how they affect Brassica acceptance.

The researchers used gas chromatographyolfactometry-mass spectrometry to identify the main odor-active compounds in raw and steamed cauliflower and broccoli. Then, they asked 98 child/parent pairs, with children between 6 and 8 years of age, to rate the key odor compounds. Dimethyl trisulfide, which smells rotten, sulfurous and putrid, was the least liked odor by children and adults. The team then mixed saliva samples with raw cauliflower powder and analyzed the volatile

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From the ACS Press Room

Blowing Up Medieval Gunpowder Recipes

“Evolution of Medieval Gunpowder: Thermodynamic and Combustion Analysis” ACS Omega

First used for battle in China in about 900 A.D., gunpowder spread throughout Eurasia by the end of the 13th century, eventually revolutionizing warfare as a propellant in firearms and artillery. Meanwhile, master gunners tinkered with gunpowder formulas, trying to find the ideal concoction. Now, researchers reporting in ACS Omega have recreated medieval gunpowder recipes and analyzed the energies released during combustion, revealing that the evolution of the perfect powder was a slow, trial-and-error process.

Although largely obsolete in modern weaponry, gunpowder, also known as black powder, is still used in historical weapons, fireworks and pyrotechnics. The explosive is a combination of varying ratios of potassium nitrate (or “saltpeter”), sulfur and charcoal. Medieval recipes sometimes included interesting additives, such as camphor, varnish or brandy, with obscure purposes. Dawn Riegner, Cliff Rogers and their team of chemists and historians wanted to analyze the energetics of medieval gunpowder recipes to help understand the intent of master gunners in creating these formulas, as well as to provide important technical information about early gunpowder manufacturing.

Researchers tested medieval gunpowder recipes in this replica of an early 15th-century stone-throwing cannon.

Credit: Adapted from ACS Omega 2021, DOI: 10.1021/ acsomega.1c03380

To do this, the researchers identified over 20 gunpowder recipes from medieval texts dated 1336 to 1449 A.D. They prepared the powders and measured the energies released just before and during combustion using differential scanning calorimetry and bomb calorimetry. They also tested a few of the recipes at a West Point firing range using a replica of an early 15th-century stone-throwing cannon.

In general, in the period 1338–1400 A.D., the percentage of saltpeter increased and charcoal decreased, causing lower heats of combustion, which could have produced safer recipes for