Ponder the TV dinner cranberry sauce – yes, there is a patent for that.

Ponder the TV dinner cranberry sauce – yes, there is a patent for that.

Image from vintage Swanson's TV frozen dinner ad showing cranberry sauce

Tinfoil & frozen slabs of food.

Ever lay in bed wondering about something and become obsessed with it? Over the past weekend, for reasons that admittedly mystify me, I became obsessed with the little cranberry slots in frozen tv dinners. You know that scoop of jellied red stuff that comes with frozen turkey dinners? It’s supposed to be cranberry sauce. What I began to wonder is, why doesn’t it turn into a pile of liquid goo when it’s heated in the oven? Why doesn’t it melt?  Guess what? There’s a patent for that, plus some mad cooking chemistry.

“Cranberry sauce is now so widely recognized as an almost indispensable accompaniment of any turkey dinner, that it is sorely missed when omitted from frozen turkey TV dinners.”
1964 Patent filing Ocean Spray

Ocean Spray was right, turkey dinners aren’t complete without cranberries. It’s big, big business. I can’t even envision Thanksgiving without a big dose of cranberry sauce. Adding a little tray of it to a tv dinner would be a strong selling point. Scoff at such an invention as cranberry sauce that maintains its form after being frozen & then heated, but it boils down to marketing dollars.

To Google Patent Search!

Of course, my first stop was a quick search of patents and there it was – the magic behind solidified cranberry sauce, courtesy of Ocean Spray, the cranberry behemoth in the US. They filed a patent for that tiny bit of red stuff in 1964 titled METHOD OF MAKING FROZEN DINNER CRANBERRY COMPONENT, United States Patent 73,360,385 granted 1969.

“A method for maintaining cranberry sauce in a gelled state upon thawing of a frozen TV dinner, comprising adding an acid tolerant, quick acting freeze surviving vegetable gelling agent such as hot hydrated starch to cooked cranberries, adding a sugar syrup, cooking the mix to form a sauce, placing an individual serving of the cooked sauce in the TV dinner package and subjecting the contents to a freezing environment to freeze said sauce.”
Patent filing Sept. 9, 1964, Ser. No. 395,323

Now, here’s the problem tv dinner makers faced with cranberry sauce – it wasn’t friendly to freezing.  It also wasn’t friendly to being made in large quantities. When manufacturers tried, they were left with “packages … on thawing, in an un-gelled flowing liquid so unfamiliar as to be unacceptable to the consumer” [r/f Patent]. Such a mess was unappetizing to the average consumer. So, they were faced with the conundrum of how to make cranberry sauce on a large scale, have it freeze and bake while maintaining a shape and consistency acceptable to the public – but still be cost effective.

Troubles with cranberry sauce stabilization.

An interesting issue subsequently cropped up, even after a stabilized product was made – the mechanized process of dropping the sauce onto the tv tray broke down the gelled status, creating the same problem. Something in the mechanical pumping system caused the problem.  The option of having the cranberries scooped onto the tray by hand was discarded. It was far too time consuming and labour intensive to be profitable.

So that left them with the same problem – how to get cranberries onto the tray quickly and still have it recognisable.  The solution lay in cooking chemistry. After experimenting, Ocean spray produced this mixture:

  • 500 pounds of cranberries
  • 30 pounds waxy corn starch to act as a gelling agent
  • 60 pounds of sugar syrup
  • 30 gallons of water.

The cranberries were cooked down in 25 gallons of water (at around 190F) and then strained.  The starch was mixed to the remaining water and heated to 190 F and then added to the cranberries. The syrup was immediately added and cooked until the mix reached an acceptable consistency. The sauce could then be piped directly onto the trays while hot and sent off to be quick frozen. When Ocean Spray popped the dinners into an oven, the cranberry sauce remained in a gelled state and didn’t “contaminate” the rest of the foods. And the rest is marketing history – turkey dinners complete with a little compartment of cranberries.

That’s interesting chemistry at work – you need just enough gelling agent and the right temperature to obtain optimal jelly status on an industrial scale. What’s not to love about that little blob of gelled cranberry sauce that is impervious to mechanical insertion, heat and freezing?

One thing that comes to mind is, has the recipe been altered now that that the dinners are on microwavable cardboard trays? Did they have to alter the recipe? Does microwaving effect the formula? Something to look consider.


Read the original patent here – Method for making frozen dinner cranberry component

Vintage ad for Swanson TV dinner with Turkey and cranberry sauce

Does Swanson still make this?

Check out my newest cranberry related patent.

Holidays, cranberries & 1 patent to put ridges on the jelly


“Drive like lightening”, the Robertson Screw

“Drive like lightening”, the Robertson Screw

How’s this for a piece of cool technology, the Robertson Screw?

Image of a Robertson screw courtesy By User:Saforrest - Taken by User:Saforrest on 9 October 2007, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2888264

Behold – the Robertson Screw

How many of us have cursed the traditional flathead screwdriver- usually that nanosecond you feel it slip in the groove and you know you’re about to suffer a disgustingly, ugly hand wound. Or cursed the Philips screw because the little star shape became damaged when the driver slipped.  There have been many attempts at improving the basic screw and my favourite is a Canadian innovation.

Development of the Robertson screw

Image of P. L. Robertson's patent illustration of Robertson Screw @1908

Patent illustration of Robertson Screw @1908Why is this a great example of tech at work? The design improves on an old idea – slip a screwdriver into the snug little square head and you can get an amazing amount of power behind it. Well, plus, for people like me who are a menace around power tools of all sorts, you never run the risk of the drill winging off creating embarrassing divots along the woodwork. There is a reason I don’t do home repairs.  But I’ll leave that for another tale.

Photo of P. L. Robertson, inventor of Robertson screw

P. L. Robertson, inventor of Robertson screw

Peter Lymburner Robertson is one of those underappreciated Canadian inventors who built a small empire a one small screw. Although many are familiar with the square head screw (commonly referred to as a Robertson), few associate it with the man who invented it. That’s him over at the side. Robertson was living in Hamilton, Ontario and worked as a travelling salesman for a Philadelphia tool company.  He often related a tale of how and why he invented the square screw. Robertson was demonstrating a spring loaded screwdriver in the summer of 1907 (the date varies between 1906 and 1907, depending on which source you look at) when it slipped and he received a bad slice on his hand. After that, he began designing a slip-less screwdriver. Withing a year, he had a satisfactory design and filed for a patent in Canada. By 1912, he held the patent internationally.

The simplicity in the design is awe inspiring:

This invention relates to screws, the heads of which have axial driving recesses or cavities instead of transverse slots punched therein and the invention consists in a recess or cavity extending into the screw head, the outer portion of the recess or cavity being prismatic and the inner portion thereof being pyramidal, the apex of the pyramid being in the axial line of the prism and of the screw. (from patent papers)

In short, the screw slot is square and punched deep into the screw head rather than a slot running the length of the screw. What makes this screw so much better than a slotted one?  Plop the screwdriver into the recessed square and it’s gripped tightly with nowhere really to slip off. You can start turning with no fear of it popping out. As well, the grip is so solid, you can put a lot of force behind each turn of the screw. The square shape also makes for a much hardier screw and more difficult to strip. As well, because the screwdriver fits so snugly into the square head, it’s possible to drill the screw with one hand, adding to its overall utility. 

Ad for the Robertson Screw

Robertson Screw ad

This was an important innovation, especially with industries looking to save time and money – a screw that could be inserted faster saved big dollars. It’s a bit hard to believe, but consider this, fewer slips of the screwdriver meant less damage to the item being manufactured. A win, win situation.

Robertson screw fails to gain a foothold

After WW1, the Ford Motor Co initially used the Robertson on its Model T and A cars. By using the Robertson, Ford said his company could save an average 2 hrs assembly time on each vehicle. This presented a massive advantage in both savings and getting cars to market faster. The deal to use the Robertson fell apart when Ford wanted P.L. Robertson to sign an agreement that would allow Ford to make and hold all distribution rights for the huge US market. Robertson was averse to signing a deal that potentially meant he would lose control over his invention.  Robertson refused to turn any rights over and unfortunately, when no monopoly was forthcoming, Ford switched over to the Philips screw. Philips was more than happy to hand over the rights.  In an odd twist of fate, this failed deal meant the Robertson never really took hold in the US, but it’s ubiquitous here in Canada. I doubt there are many toolboxes that don’t have a few Robertson screw drivers rolling around inside.

Read more:

Archives Canada – Robertson Screw and Screwdriver
You can download the patent here: https://patents.google.com/patent/US975285A/en?q=screw,roberston&inventor=Peter+Robertson&before=19100101
Robertson Fastener website has a bit of info as well

In honour of Exploding Battery Week – the Daniell Battery

In honour of Exploding Battery Week – the Daniell Battery

Every time you fire up your phone, stop and offer thanks to English chemist and all-around polymath, John Frederick Daniell (1790–1845), inventor of the Daniell Battery. He’s the dapper fellow to the in the picture below. No, he didn’t design the first battery, he was second, but his design has been described as the first practical battery. Alessandro Volta (volt … volta … get it?) developed the first battery.

John Frederick Daniell, inventor of the Daniell Battery

Photo of John Frederick Daniell British chemist

John Frederick Daniell, British chemist

Daniell was a typical 19th century intellectual – a busy, active mind that wasn’t constrained by one discipline – chemistry, physics, meteorological, climatology and a little bit of geology thrown in.  He started his career working at a sugar works where he developed a technique for clarifying sugar.  He later went on to patent his idea. I tried to find the patent but had no luck. Anyone want to fund a trip to the UK archives? I think I could spend a lifetime there looking at patents.

Anyway, while working at the sugar plant, he attended lectures at the Great Windmill Street Anatomical School in London.  It was there that his interest in chemistry was encouraged.  He sat in on lectures by William Thomas Brande, chemist, author of the Manual of Chemistry and later professor at the Royal Institute. The Great Windmill had a powerful influence on Daniell’s passion for chemistry. While there, he formed a lasting friendship with both Brande and Michael Faraday – a name that should ring a bell or two with most of you.

 Illustration of John Frederick Daniell and Michael Faraday from Sketches of the Royal Society and Royal Society Club by Sir John Barrow

John Frederick Daniell and Michael Faraday from Sketches of the Royal Society and Royal Society Club by Sir John Barrow

By 1830, Danielle had established a name for himself in the fields of chemistry and meteorology.  His work and influential friends (Samuel Taylor Coleridge among them) helped Daniell obtain the position of first professor of chemistry with the new King’s College London where he could devote all his efforts to science and not on the mundane matter of working to support family. While at King’s College, Danielle worked on advancing Volta’s battery, developing a battery that would be named the Daniell Cell.

So just what was the Daniell Cell? Let’s see if I can get this right the first time. The Daniell Cell was pretty much a copper pot stuffed with a copper sulfate solution. That pot was put into another pot made of earthenware rather than metal. It in turn was filled with sulfuric acid. A zinc electrode was put into the mix to create a reaction. By building on the works of both Volta and Faraday, Daniell created a battery that produced an electric current that was stable and eliminated the pesky and dangerous hydrogen bubble problem that formed with Volta’s model.

Here’s a Daniell Battery Cell:

Photo of an early Danielle Battery 1836

Photo of an early Danielle Battery 1836

And here’s another one:

Photo of an early Daniell Battery 1836 courtesy University of Malta

Photo of an early Daniell Battery 1836 courtesy University of Malta

Looks a bit … er … dangerous. Not to mention not very portable, but then that wasn’t a necessity.  I don’t think modern Health & Safety would be impressed.  But here’s the thing, Daniell’s ground-breaking invention fueled a boom in communications.  It was the building block for the expansion of the new telegraphic network that snaked throughout both the UK and US and the new electrical industry until well into the 1870s when newer developments made the Daniell obsolete.  The chemical reaction in the battery sparked the currents that drove the burgeoning communication advancements … all leading 200 years later to your little smart phone.

Technology. Amazing, isn’t it?

Read more:

You can read more on how the Daniell Cell works here: Notes from the Oesper Collections The Daniell Cell William B. Jensen Department of Chemistry, University of Cincinnati, Cincinnati, OH. It opens a pdf you can download and read.

Read more about John Daniell: https://www.chemistryworld.com/opinion/daniells-cell/7919.article and the Encyclopedia of World Scientists (Rev. ed) by Elizabeth Oakes.

Technological marvels –  lowly & underappreciated pencil sharpener

Technological marvels – lowly & underappreciated pencil sharpener

We don’t spend much time thinking about the little bits of technology that make life easier, do we? Here’s a case – the pencil sharpener. When was the last time you thought about one, other when you couldn’t find it and cursed the blunt point on your pencil?  Here’s my favourite:

photo of Staedtler pencil sharpener

Best pencil sharpener around – the Staedtler

The little metal Staedtler sharpener. I own 5 of them, including 2 hole, single hole and covered sharpeners. Oh and I have 2 of their beautiful mechanical pencils and about 20 of the Mars Lumograph pencils. I have a thing for tidy, beautiful examples of technology that works. I also have a thing for Staedtler. The first time I saw a Staedtler sharpener, I coveted it. I was in the library and watched, with envy as someone whipped out a little perfect work of technological art and sharpened pencils. I leaned over the table and asked him where he got it.  I was awestruck. When I finally found one I bought it. It was beautiful.  The little metal body makes it durable – can’t tell you how many of those dreaded little plastic ones I’ve crushed over the years.  And quite honestly, the plastic sharpeners are crap, they break off the point because the angle of the blade is often just off enough that it gouges out chunks of pencil. The little Staedtler shaves off thin slivers of wood and hones pencil leads to a perfect point. Maybe I should just retitle this “Ode to a pencil sharpener” and be done with it.  The angle and quality of the blade, durability of the casing, the ridges on the sides to make holding it easier – everything about the sharpener is “right”.

My mini love affair with Staedtler pencil sharpeners (and pencils) sparked a bit of curiosity about the evolution of sharpeners. While searching, I found some intriguing early patents for pencil sharpeners and references to the first practical design. Bernard Lassimonne, a French mathematician, is credited with receiving the first patent for a pencil sharpener.  I’m searching for a copy of it, but I’m a bit hindered by my disgraceful French. He evidently took an ad out in Le Constitutionnel, a French newspaper, sometime in 1829 to promote his invention. I’m also searching through the newspaper’s archives and hope to find the ad, but … it may take me a long time to find it.  Although I’m having little luck with my initial search, I have found what I think would have been the coolest sharpener ever – the G. H. Park pencil sharpener and lead protector: Patent #193,545, Patented July 24, 1877. You can see the original patent here.

Here’s one view of it, from the patent papers:

Drawing of G. H. Park's pencil sharpener from his 1877 patent

Drawing of G. H. Park’s pencil sharpener from his 1877 patent

In 1877, George Park, of New York State  “invented a new and valuable improvement in pencil-sharpeners” and it’s pretty damned cool:

“This little instrument is intended to remain on the pencil while in use and until the pencil is consumed.

It also forms a point-protector, as it can be pulled down sufficiently far to bring the point of the pencil within the sharpener, and when the pencil is to be used it is readily pushed out again, the spring of the metal holding the instrument at any point on the pencil.

The instrument thus forms a combined sharpener and point protector, and it can be manufactured at a very trifling cost, and is simple, durable, and effective in operation. It adapts itself to any-sized pencil, and is not liable to be lost, as the spring of the metal holds it with sufficient tension or friction on the pencil.”

Image from patent papers for the pencil sharpener

Image from patent papers for the pencil sharpener

Here’s another view that offers a better idea of how it fits on a pencil:

So, you slip the sharpener onto the pencil, it automatically expands or contracts to fit the body and, as you shave the pencil down, will hold the lead point so you don’t snap it off by accident. It’s like hybrid mechanical pencil when you think about it.  No more searching for your sharpener – it’s always attached.  Might be a bugger if you lose your pencil though. I’ve looked around to see if it was ever produced and can’t’ find any examples. Maybe it was one of those great ideas on paper that didn’t translate to real life. There were a number of similar designs that promoted “ever point” sharpeners and a couple made it to market. But not a sign of this one. Kind of a pity really.

Visit my Facebook page and hit the Like button if you want to see more old patents. I’ll be exploring more over the coming months. If you have a favourite, drop me a line (either below in the comments field) or on the Bitter Grounds Facebook page

What’s old is new again – 1902 called & wants its B-2 Stealth back

What’s old is new again – 1902 called & wants its B-2 Stealth back

I was amused by a discussion on-line not long ago where someone asked “what did people do before technology”, meaning back in the dark days of the 1980s.  I chuckled because of the assumption technology is shiny new and millennial. It often comes as a shock to people when you point out the wheel is technology and that  tech is nothing more than the “application of scientific knowledge for practical purposes, especially in industry” (Oxford dictionary).  

So … I thought it might be fun exploring tech – of all types. I often wander through Google’s Patent search engine looking for cool stuff. My favourites are proposals that never quite made it off paper. Not all were fails, some were simply ahead of their times. Some were a combination of too soon and too impractical. To wit: Theodor Gibon’s, of Clarksville, Tennessee, aeroplane (Patented Sept 30, 1902):

image of the Theodore Gibon V wing aeroplane patent 1902

Look vaguely familiar? While everyone was mad for straight wing designs, in 1902 good old Theodore took a different approach. He created a sleek, single delta that was ahead of it’s time in terms of wing design. This sweeping v resembles the modern B-2 Stealth bomber. Or rather, the B-2 looks like the T. Gibon aeroplane. Okay, yes I agree, the Gibon looks more like a paper airplane, but you get my point.

Andreas Theodor Heinrich Gibon, born in Bremen, Germany, was living in the US around the turn of the century.  Although the records show he immigrated in 1895, he still identified himself as a German subject at the time of filing the patent – “Be it known that I, THEODORE GIBON, a subject of the Emperor of Germany, and a resident of Clarksville, in the county of Montgomery, State of Tennessee”.   The census records of 1910 ad 1920 show he had settled into a job as a tobacconist in a local factory so I guess, by 1910, he had given up hopes of developing aircrafts any further. Searching for any other patents in his name came up empty.

You can read the full patent here: https://patentimages.storage.googleapis.com/pdfs/6d2fc0b7820fa0a52bcf/US710266.pdf It’s 2 pages and filled with wonderfully sci fi sounding ideas. I read the patent but got lost in the babble about “motive fluids” that would drive the … engine? Come to think of it, he didn’t describe any engine, just a series of pipes carrying liquid air around the airplane. Flight would be achieved by opening and closing various valves and ultimately discharging the liquid through vents. Basically, he designed the ultimate glider, but included a mechanism to control wind currents to propel the airplane.

under the impulse of the reaction from the stern discharges and from any or all parts of the wing-sections, too, if desired, the machine will fly rapidly forward to the 45 positions km, &c., and continue on that tack as long as the engineer may deem expedient.. In like manner the aeroplane may be steered to the left or to the right by causing discharges of motive fluid from the right or the left side 50 of the wings or body, as will be readily un­derstood.
from Letters Patent No. 710,266, dated September 30, 1902.  Application filed April 24, 1901. Serial No. 57,229

Was it at all practical? Not a clue, I’m not even going to pretend to understand the basics of flight or mechanics. My knowledge of flight is limited to buying a ticket and getting to my seat.  I do suspect the entire fluid reaction mechanics are pretty pie in the sky stuff. But the wings … the wings!

It’s interesting to see a design we associate with the cutting edge sitting on a 100+ year old patent. Gibons ran contrary to the trend of straight wing designs, including multiple layers of wings. His single, swept back v, despite the rudimentary drawings, indicates an vision for aerodynamics that was ahead of his time.

Here’s the back view:

Back view of the Gibon flyer 1902Invert it and you have:


A forerunner of the B-2, although admittedly the Gibon does look more like an origami project on steroids. Or maybe one of those spaceships on Stargate – the flying pyramids. Regardless, when the Stealth was revealed, people were left breathless with the flying wing design. There is an element of a bold dreamer in Gibon’s patent. Too bad he didn’t live to see the B-2 fly. His mechanics may have been nonsense, but the wing design was spot on.

Oh yea, I love trolling through old patents. You just never know what you’ll find.