Jio Platforms, the digital and telecom arm of Mukesh Ambani’s Reliance Industries, filed its draft red herring prospectus with India’s securities regulator on Friday for what would be the country’s largest initial public offering. The filing covers a fresh issue of up to 270 million shares, with no offer-for-sale component, meaning every rupee raised flows directly into the company’s balance sheet.

The IPO is expected to raise approximately $3.8 billion, according to people familiar with the matter. That would surpass Hyundai Motor India’s $3.3 billion listing in October 2024, currently the record for an Indian maiden offering.

The DRHP specifies that 275 billion rupees ($2.9 billion) of the net proceeds will go toward prepaying external commercial borrowings held by Reliance Jio Infocomm, its telecom subsidiary. The remaining funds are earmarked for general corporate purposes.

The borrowings in question consist of three loan facilities denominated in dollars and yen, totaling 300.6 billion rupees. Lenders include Australia & New Zealand Banking Group, Bank of America, Barclays, BNP Paribas, and Citibank. All three facilities are scheduled for repayment between March and June 2028, but Jio Platforms intends to prepay them in full or in part from the IPO proceeds.

Ambani announced the filing at Reliance Industries’ 49th annual general meeting on June 19, describing the listing as a step toward unlocking value for shareholders. The IPO will be led by Akash, Isha, and Anant Ambani, the next generation of the family.

Nineteen banks have been appointed as book-running lead managers, including Morgan Stanley, Goldman Sachs, J.P. Morgan, and Kotak Mahindra Capital.

The deleveraging strategy is significant. Jio Platforms’ net debt stood at 275.8 billion rupees as of March 2026, down from 452.7 billion rupees a year earlier and 484.4 billion rupees in March 2024. A successful IPO would eliminate the bulk of the remaining foreign currency exposure and reduce the company’s annual servicing costs.

The company said in the prospectus that repaying the debt would improve its ability to raise future resources for business development and position it for continued investment in 5G network densification, fixed broadband expansion, and AI and cloud services.

Jio Platforms operates through its telecom subsidiary Reliance Jio Infocomm, which is the world’s second-largest mobile operator by single-country subscribers after China Mobile. As of March 2026, it had 524.4 million subscribers, with 268.5 million already on its 5G network, making it the largest single-country 5G operator outside China in a market racing to scale its digital infrastructure.

In the financial year ending March 2026, Jio reported operating revenue of approximately 1.47 trillion rupees ($15.6 billion) and a net profit of roughly 300 billion rupees ($3.2 billion). EBITDA rose 18.8% to 762.6 billion rupees, with margins improving to 51.9%.

At a valuation above $130 billion, which analyst estimates place between $131 billion and $180 billion, the IPO would make Jio Platforms one of the most valuable companies to list in Asia. The offering represents roughly 2.9% of post-issue equity, enabled by a March 2026 regulatory change that allows companies valued above 5 trillion rupees to list with just 2.5% public float.

Meta holds a 9.99% stake and Google holds 7.73%, both acquired during a 2020 fundraising round that brought in more than a dozen global investors including KKR, Vista Equity Partners, Silver Lake, and sovereign wealth funds from Abu Dhabi and Saudi Arabia. The fresh-issue structure means none of these investors are selling in the IPO itself, though the DRHP does not restrict future secondary sales once lock-up periods expire.

The timing places Jio’s filing alongside a broader wave of major Asian tech listings. At the same AGM, Ambani outlined a $110 billion AI infrastructure investment over seven years and announced a partnership with Meta to build an AI data centre in Jamnagar, Gujarat. The IPO proceeds, by clearing the balance sheet of foreign currency debt, would free up capacity for those commitments.

India’s broader push toward technological self-reliance and sovereign AI infrastructure adds a geopolitical dimension to the listing. Jio has positioned itself as the backbone of India’s digital economy, and its 5G and AI ambitions align with the government’s stated goal of reducing dependence on foreign technology platforms.

Existing Reliance Industries retail shareholders will receive a dedicated quota in the offering, with up to 35% of the issue reserved for retail investors. Price band, lot size, and bidding dates have not yet been disclosed, which is standard at the DRHP stage. These will follow once SEBI issues its observations and Jio files its final prospectus.

The draft document did not specify the IPO’s total size in rupee terms, as the issue price will be determined through book building. However, based on the 270 million share figure and prevailing valuation estimates, the offering is expected to land in the range of 360 billion rupees.

The house is quiet, but you’ve already started receiving notes. In the near future, you wake up at 6:43 am.

The sleep tracker reports poor recovery. The watch recommends a lighter day, which is considerate, if not especially informed. Somewhere in the stack of sensors, last night has been converted into a verdict. There isn’t enough sleep or rest, and the day hasn’t even started asking for things yet.

The device isn’t being especially cruel. In 2024, CDC/NCHS found that 30.5% of U.S. adults had short sleep duration, and only 54.8% woke up well-rested.

The morning, apparently, now begins with a software intervention.

When the routine gets a management layer

By the time the front door opens, your routine has acquired a small staff.

The smart glasses skim messages and calendar items into the corner of your eye.

The AirPods press the commute into something survivable.

The watch catches your heart rate, the ring follows your recovery, the glucose patch waits for lunch like a tiny food critic, and the posture tracker buzzes when your spine gives up pretending.

Somewhere below, the smart insoles notice your walk has changed.

The market is already moving in that direction, which is unfortunate for anyone hoping this stays a joke. Circana reported that US fitness tracker revenue grew 88% year over year in the first seven months of 2025, while smart ring unit volume jumped 195%. Smart rings also accounted for 75% of total fitness tracker revenue so far that year.

When lunch can file a report

Wearables aren’t satisfied with counting your steps and congratulating you for standing up anymore.

The category is drifting toward interpretation: recovery, glucose response, posture, strain, readiness, and the suspicious moral weather of your body.

The question was never whether these gadgets are useful. Many of them are.

Glucose monitoring shows the direction of travel. Ultrahuman recently announced M2 Live, a US continuous glucose monitoring service built around Abbott’s Lingo biosensor, with no prescription required. It costs $99 per month, with sensors sold separately for $129 and worn for up to 14 days.

The appeal is obvious. The joke is worse: lunch can now file a report.

When every fix becomes another nudge

One gadget disappears into a routine. Seven of them turn your routine into a meeting.

A watch can catch something real. A glucose patch can reveal a pattern. Smart glasses can make the day less messy. AirPods can make the commute less hostile.

The unease comes from the accumulation. The day keeps asking for more: more messages, more sitting, more rushed meals, more sleep debt, more cheerful little boxes to tap before work has even started. Then tech arrives with small corrections for every injury the day has already made. Breathe here for a minute. Stand up before the next call. Eat differently at lunch. Walk cleaner on the way home. Please consider becoming a slightly improved mammal.

The question was never whether these gadgets are useful. Many of them are. The better question is what gets lost in the rounding.

The afternoon you wasted and didn’t regret. The version of yourself that exists outside the dashboard. The grief that didn’t resolve into a trend line. None of that generates clean data, and clean data is, increasingly, the most expensive thing you have to offer.

Your routine continues whether or not you’re really home.

The future cyborg won’t need a weapon. You’ll need a nap, and at least three devices will take credit for suggesting it.

And somewhere in a data center the size of a small city, a server notes that the nap was 23 minutes too short, flags the cortisol trend, updates your profile, and quietly adjusts tomorrow’s recommendations.

The house is quiet. Somewhere on your wrist, your finger, your spine, your foot, the notes keep coming.

Signal president Meredith Whittaker has warned that AI chatbots “are not your friends,” “are not conscious beings,” and “are not sentient interlocutors,” pushing back against the growing tendency of users to treat AI systems as trusted companions. The comments came in a Bloomberg interview published this week in which Whittaker laid out her case that the agentic AI vision promoted by companies like Microsoft amounts to a new form of surveillance infrastructure.

Whittaker, who has led the encrypted messaging nonprofit since September 2022, acknowledged that she uses AI tools “to format a document here and there” but drew a hard line at anything more substantive. “I don’t ask them questions,” she said.

“I’m very serious about my thinking and writing, and I don’t want the process of working through an idea to be foreclosed or eclipsed by the response of a system that’s averaging what’s already out there,” she added.

Her sharpest criticism was directed at Microsoft AI CEO Mustafa Suleyman’s prediction that users would be able to let Microsoft Copilot handle all their Christmas shopping by eavesdropping on family group chats to determine who wants what. Whittaker methodically listed the access such a system would require: “my credit card, my browser, my Signal, the ability to message my siblings on my behalf, my home address, my calendar.”

“What you’ve just described is a system with very pervasive access across multiple applications and services,” Whittaker said. “In the context of Signal, it would constitute a kind of a backdoor.”

The backdoor framing is deliberate and carries weight coming from the head of Signal, which operates the most widely used end-to-end encrypted messaging protocol in the world. Signal’s encryption is also used by WhatsApp, which has more than two billion users. Whittaker has previously said the organisation would leave the EU rather than comply with any law requiring it to compromise its encryption, a position she reiterated when the European Parliament voted in April to let its ePrivacy derogation expire rather than extend voluntary scanning of private messages for child sexual abuse material.

The core of Whittaker’s argument is that agentic AI systems, which need near-total access to a user’s digital life to function, are structurally incompatible with end-to-end encryption. An AI agent that can read your messages before they are encrypted, or after they are decrypted, renders the encryption irrelevant from a privacy standpoint. It does not matter that the messages are encrypted in transit if a system with root-level access is processing them in plaintext on the device.

Whittaker has been making this case with increasing urgency. In January 2026, she warned at Davos that agentic AI was “perilous” for secure applications. In an essay for The Economist, she accused operating system vendors of “hollowing out” Signal’s ability to guarantee privacy by embedding agents into their platforms.

She has described prompt injection, where an attacker manipulates an AI agent into executing unintended commands, as the likeliest first exploit path against encrypted messaging platforms.

Microsoft is building an entire operating system around agent-first computing with Project Solara, unveiled at Build 2026, which replaces traditional apps with AI agents as the primary interface. Google, Apple, and OpenAI are pursuing similar strategies.

Whittaker’s position is that this architectural shift, where agents mediate every interaction between users and their devices, creates databases of entire digital lives that become prime targets for both hackers and governments.

The interview also touched on the broader AI anthropomorphism problem. Suleyman himself has warned about “seemingly conscious AI” and “AI psychosis,” where users believe chatbots are sentient. Whittaker’s framing was more direct: the systems are designed to mimic empathy and understanding, but the underlying mechanism is pattern-matching across training data, not comprehension.

Treating them as confidants means volunteering sensitive information to systems whose data handling practices are opaque and whose operators have commercial incentives to retain and analyse that data.

Whittaker’s position places her at odds with the dominant narrative in Silicon Valley, where the agentic future is presented as an inevitability that will make users more productive. Her counter-argument is that productivity gains achieved by surrendering control of your messages, calendar, contacts, and financial information to a corporate AI system are not gains at all, but a transaction in which users trade privacy for convenience without understanding the terms.

Waymo delivers more than 500,000 paid rides per week across 10 US cities, raised $16 billion in February, and is expanding internationally to Tokyo and London. It cannot operate in New York City.

The reason is not technical, it is political.

As the New York Times reported this week, opposition from local politicians, labor unions, and an influential taxi lobby has stopped the Google-owned robotaxi company from entering the country’s largest and most lucrative ride-hailing market. The roadblocks are structural, not temporary.

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New York Governor Kathy Hochul introduced a budget proposal in January that would have legalized commercial robotaxi pilots across New York state, excluding New York City. A month later, she withdrew it. The pushback from driver groups, transit workers, and state legislators was immediate and overwhelming.

“Based on conversations with stakeholders, including the legislature, it was clear that the support was not there to advance this proposal,” a spokesperson for the governor told CNBC. The reversal killed Waymo’s most promising regulatory pathway into the New York market.

Newly elected NYC Mayor Zohran Mamdani has made his position clear. Mamdani, who went on a hunger strike alongside taxi workers during his earlier political career, has declined to renew Waymo’s testing permit, which expired on March 31. The permit, approved by former Mayor Eric Adams in August 2025, had allowed Waymo to test eight Jaguar I-PACE vehicles with safety drivers in Manhattan and downtown Brooklyn.

No collisions were reported during the entire testing period, according to NYC’s Department of Transportation. That fact has not changed the political calculus.

“Our strategy remains the same,” Waymo’s global head of public policy Justin Kintz told the New York Times. “We want to meet people and governments where they are.”

“We know that some of them will take more time than others,” Kintz added. “But we’re committed to earning trust.”

The company has spent at least $1.8 million lobbying New York state officials since 2019, according to state records, and recently retained The Parkside Group at $15,000 per month to lobby on autonomous vehicle legislation. The money has not moved the needle.

The standoff reflects a broader tension in the robotaxi industry. Waymo must approach each state and city individually for permission to operate, a patchwork regulatory environment that gives local politicians effective veto power. Legislation has stalled in at least eight states, including New York, Virginia, Oregon, and Minnesota, even as 18 states now allow fully driverless commercial operations.

Waymo’s technical record in New York was clean, but its broader safety record is more complicated. The company issued its sixth recall this week after robotaxis drove into highway construction zones 13 times across Phoenix and the San Francisco Bay Area.

A rider told CBS News they thought they were going to die. Waymo offered three free rides worth up to $40 each.

The recall pattern gives ammunition to Waymo’s opponents in New York. New York Magazine argued that what could reverse the Mamdani administration’s resistance would be proof that the vehicles are safe, beyond the company’s own statistics. That is difficult to demonstrate when the company is simultaneously pulling its fleet off highways because the software cannot reliably detect cones and closure signs.

The economic stakes are enormous. Waymo is deploying its new, cheaper Ojai robotaxi and targeting one million weekly rides by the end of 2026, with plans for more than 20 additional cities including international markets. New York City, where over 100,000 for-hire vehicle drivers operate and the taxi industry generates billions annually, would be its single most valuable market.

But the city’s taxi medallion system has already been through one near-collapse, when Uber and Lyft decimated medallion values from over $1 million to under $200,000 a decade ago. Taxi drivers who fought back from that crisis are not interested in another disruption. The New York Taxi Workers Alliance, which represents roughly 28,000 drivers, has framed the fight against robotaxis as a labor rights issue.

The competitive landscape is shifting around Waymo while it waits. GM is rebuilding its autonomous vehicle program after shutting down the $10 billion Cruise division. Tesla has launched a limited robotaxi service in Austin, and Amazon’s Zoox operates in San Francisco and Las Vegas.

None of them are in New York either, which suggests the city’s resistance is not Waymo-specific but industry-wide.

For now, Waymo’s $16 billion war chest and 500,000 weekly rides have not purchased entry to the one market that matters most. The company’s strategy of patience and lobbying may eventually work, but in a city where taxi drivers have political allies in the mayor’s office, the state legislature, and the labor movement, “eventually” could mean years.

The second day of the BMPS Grand Finals has just curtailed, and as expected, it was the day of comebacks from the likes of GDR, who finished second in the overall standings just after table toppers Divine. Another big comeback came from Vacista Esports, who finished third in overall standings, thanks to the multiple chicken dinners. Sadly, it wasn’t all sunshine for teams like TAG, who failed to mount a challenge for the top once again, succumbing to blind pushes and unnecessary moves. Here’s what the standings look like after day 2 of the BMPS Grand Finals.

BMPS Grand Finals Standings After Day 2

Day 3 is up ahead tomorrow, and Divine still has a comfortable lead ahead of all the pack. It’ll be interesting to see if they can continue this timid momentum, or if someone from the likes of GDR, VS, or even GodLike makes a dent in anyone’s plans to catch the flight to Paris.

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So, you’re tired of seeing rotating ads or Amazon’s preloaded graphics on your Kindle every time you put it to sleep. That’s understandable, especially if you’re voracious reader who’s been spending a lot of time on your ereader. In this piece, we’re going to walk you through how to change your Kindle sleep screen and even how to personalize it if you want. 

How to remove Kindle Special Offers

Kindles with Special Offers or lockscreen ads typically cost $20 less than the versions without them. These devices will show you a rotation of advertisements for books, for more Kindle devices or for Kindle Unlimited whenever you put your Kindle to sleep. As long as your device is ad-supported, you cannot customize your screensaver, so your first step is removing Special Offers from your ereader, which will understandably cost you some money. If your Kindle doesn’t have lockscreen ads, you can skip this step. But if it does, you can follow these instructions:

1. On desktop, go to the Amazon website, log in and click the hamburger menu on the left side of the screen. 

• Under Digital Content & Devices, go to Kindle E-readers & Books. 
• On the next screen, click on Manage Content and Devices under Apps & Resources. 
• On the new page that loads, click on Devices near the top of screen. If you have more than one Kindle attached to your account, click the box marked Kindle under Amazon Devices and then choose the ereader you want. 
• In the Special Offers box at the bottom, you’ll find a button to remove offers for $20. Again, you’ll have to pay for it, because Amazon says the original $20 discount you got was in exchange for getting ads.

Screenshot by Mariella Moon (Amazon)

2. On mobile, fire up the Amazon app. 

• Go to the “Alexa for Shopping” tab on the bottom right corner of your screen. 
• Type in “I want to end Special Offers on my Kindle.” Alexa will link you to the Manage Devices page. 
• From there, choose a Kindle and scroll down to end Special Offers for $20.

NOTE: If you’re not in the US but somehow have a US-version Kindle, you might have issues removing lockscreen ads. Amazon will ask you to add a US address and a card with US billing to be able to pay $20 for their removal. Without both, it won’t be possible to proceed to the next step. You can try talking to customer service and asking kindly if they can disable special offers for you at no cost, but there’s no guarantee that that will work. 

How to display book covers as your Kindle screensaver

Once you’re done getting lockscreen ads removed, or if you never had them in the first place, you’ll get a rotation of Amazon-provided illustrations as your screensaver. Those who own newer Kindles have the option of using the cover of the book you’re currently reading instead (see below for a full list of supported models). To make sure this feature is turned on, follow these steps: 

• Tap the three-dot menu on the upper right-hand corner of your Kindle. 
• Go to Device Options. Find Display Cover and toggle it to On. 
• On newer or updated devices, you’ll find the “Show covers on lock screen” option in the “Screen and brightness” section. Simply toggle it on. 

NOTE: The option to use book covers as screensavers is only available on the following models: 

Amazon

How to use custom images as your Kindle screensaver

Unfortunately, there’s no way to use custom images as your permanent Kindle screensaver without jailbreaking your device. There is, however, a trick you can consider: Replacing the cover of a book  with the illustration you want to see, then opening it before locking your device. Before you proceed with the instructions below, make sure you’ve already completed the steps above to toggle on the option to display book covers as your lockscreen. 

• The first step is to create custom wallpapers on programs like Canva or to look for an illustration you want to use. Just make sure it fits the device you have by searching for the dimensions of your ereader’s screen. The latest Kindle Paperwhite, for instance, has a 7-by-5-inch display. Some people recommend creating a wallpaper measuring 2,560 x 1,600 pixels, which will work for most Kindle models. 
• After you’re done designing your custom illustration, download it as a PNG image.
• Use a program like Calibre to convert any file it supports (like PDF) into an EPUB file. You’ll find the option to set a cover for your ebook on the conversation screen, so choose the PNG image you made. 
• You can also look for an “epub cover change” website online. Upload the book you’re reading or any EPUB you have and then choose the PNG image you saved earlier for your new cover.
• Use the “Send-to-Kindle” feature to upload the finished file to your ereader.

NOTE: You will have to switch to the book that uses your custom cover before you put your device to sleep every time you want to see it on your lockscreen. Alternatively, you can change the cover of every book you read, though that sounds pretty time-consuming, especially if you blaze through books quickly. While this solution isn’t very straightforward, it’s an effective way to personalize your device. 

If Day 1 of the BMPS 2026 Grand Finals belonged to Divine Gaming, Day 2 was all about Victoris Sumus and GodsReign. Both teams consistently found themselves in the late game across multiple matches and looked like one of the most complete squads on the battlefield. At the same time, teams like GodLike Esports mounted impressive comebacks, while iQOO SouL finally showed signs of life after a disastrous opening day. Here’s everything that happened on Day 2 of the BMPS 2026 Grand Finals.

Victoris Sumus Emerges as a Serious Title Contender

The biggest story of the day was undoubtedly Victoris Sumus. The squad started strong in the opening Rondo match and eventually secured a crucial chicken dinner after outlasting GodLike Esports in the final fight. That momentum continued throughout the day as they repeatedly put themselves in winning positions.

Match 2 saw Victoris Sumus pull off one of the most surprising endgames of the tournament. Despite being forced to rotate into the zone under pressure from GodLike, the team somehow survived without losing a player. Moments later, they eliminated GodLike and secured another chicken dinner. Even when they weren’t winning matches, Victoris Sumus remained a constant threat. Their positioning, rotations, and ability to capitalize on mistakes made them one of the most dangerous teams on the server.

After spending most of Day 1 near the bottom of the standings, iQOO SouL desperately needed a response. Unfortunately, the day didn’t start well. Genesis Esports eliminated SouL in the opening match, exposing the same coordination issues that had haunted the team throughout Day 1. Match 2 wasn’t much better, as TAG stunned the crowd by wiping SouL near Pochinki.

However, things finally clicked during the Miramar games. SouL looked far more coordinated, won several crucial engagements, and secured their first chicken dinner of the tournament in Match 5. The team followed that up with another solid performance in the final game, highlighted by a clutch play from Legit that helped eliminate GodLike during the closing stages. It wasn’t a perfect day, but it was exactly the kind of comeback SouL fans had been hoping for.

GodLike Esports entered Day 2 with plenty of ground to make up and looked significantly sharper throughout the day. The team consistently found itself in favorable late-game positions and finally converted one of those opportunities into a chicken dinner during Match 3. Their aggressive pushes and grenade usage were among the best we’ve seen so far in Jaipur. While they narrowly missed out on a few additional wins, GodLike’s Day 2 performance firmly placed them back into contention heading into the final day.

TAG Continues to Entertain, But Results Remain Elusive

No team generated more crowd reactions than Team Aryan x TMG. Whether it was aggressive early-game pushes, risky compound crashes, or unconventional strategies, TAG constantly found themselves in the middle of the action.

The team showed flashes of brilliance, including a memorable win over SouL and an impressive shotgun push against Genesis. Unfortunately, their aggressive playstyle often backfired, preventing them from converting strong starts into meaningful points. TAG remains one of the most entertaining teams to watch, but they’ll need a much cleaner Day 3 to climb the leaderboard.

God’s Reign Pulls Off the Biggest Comeback of the Day

While much of the attention was on Victoris Sumus, SouL, and GodLike, Gods Reign quietly put together one of the most impressive comeback stories of the tournament. After spending much of the event in the lower half of the standings, GDR consistently picked up crucial finish points throughout Day 2. Their biggest moment came in the final Miramar match, where they secured 19 points and a chicken dinner to cap off the day in style.

That massive haul propelled them all the way to second place in the overall standings, turning them from an outside contender into a genuine title threat heading into the final day. Check out the full standings after day 2 of the BMPS Grand Finals here.

The takeaway: New research is challenging a basic assumption about espresso: that it has to be made with hot water. Instead of relying on near-boiling water, researchers have shown that high-frequency sound waves can produce an espresso-style shot with similar strength and taste – no heat required.

Developed by engineers and food scientists at UNSW Sydney, this new method is called “ultrasonic espresso” and replaces heat with mechanical energy. It runs at room temperature, using sound waves to pull flavor from finely ground coffee, and reaches espresso-level intensity in under three minutes despite the cold-water start.

The setup still begins with a standard espresso basket. A small metal transducer is mounted against its wall, and once activated, it emits ultrasound – sound waves above the range of human hearing – that travel through the water and coffee bed.

What happens next is the key step.

The sound waves trigger acoustic cavitation, a process where tiny bubbles form in the liquid and collapse in rapid succession. When those bubbles implode near coffee particles, they generate microscopic bursts of force that chip away at the grounds, speeding up the release of oils, flavor compounds, and caffeine into the water.

In effect, the system swaps heat for controlled agitation at a microscopic level, using pressure changes and localized mechanical action instead of temperature to drive extraction.

That distinction matters more at scale than it does on a kitchen counter. For a home user, skipping the heating step might not move the needle much. But in industrial settings – particularly ready-to-drink coffee production – energy consumption becomes a central concern, and the researchers estimate that eliminating the need to heat water could cut energy use by up to 75%.

The process also introduces some logistical flexibility. Because the coffee is produced at room temperature, it can go straight into bottled drinks or milk-based products, or be shipped as a concentrated liquid and diluted later, potentially simplifying production and distribution.

Ultrasound is not entirely new to coffee science. Earlier work from the same UNSW team explored its ability to speed up cold brewing, compressing what is typically a 12 to 24-hour process into a matter of minutes. But espresso presents a different challenge: it is not just about extracting caffeine or basic flavor, but about achieving a specific balance of bitterness, aroma, and body typically associated with high heat and pressure.

To hit that target, the researchers, led by Dr. Francisco Trujillo, fine-tuned several variables. Grind size played a clear role, with finer particles allowing faster extraction. The water-to-coffee ratio had to be carefully controlled to avoid under-extraction or dilution, and timing proved equally important, with the optimal window landing between two-and-a-half and three minutes of ultrasonic exposure.

Matching the chemistry of espresso is only part of the equation, though. The more practical question is whether people can actually taste the difference.

To test that, the team ran a blind evaluation with about 100 regular coffee drinkers, those findings are published in the Journal of Food Engineering. Participants sampled four coffees: traditional espresso, ultrasonic espresso, and both traditional and ultrasonic filter coffee, served at the same temperature and in random order.

The results were strikingly close. Participants couldn’t reliably distinguish between the traditional espresso and the ultrasonic version, with the two performing nearly identically across aroma, flavor, bitterness, and overall preference. In the filter category, the ultrasonic version was actually favored, with tasters describing its bitterness as more balanced.

The findings suggest that heat may not be as essential to espresso as long assumed. By using ultrasound to accelerate extraction, the process reproduces the defining characteristics of espresso while significantly reducing energy input. For an industry built around heat-driven methods, this opens up a different way of thinking about how coffee can be made.

Image credit: The Conversation