Last Friday (Platinum Jubilee weekend) the new owners of our faithful Petroncini arrived and together we dismantled it and loaded onto their hired Luton van ready for its departure on Saturday morning. It went ‘mainly’ according to plan. James, Alexx and Westy are from 17 grams in Brighton and this is their first move into roasting for their expanding cafe business.
We tried to keep as much of the working parts together to avoid disconnecting any significant wiring. Of course with all the mods that we’d had done over the years that meant quite a few extra bit and pieces. With 4 of us and a pallet truck neatly fitting under the chassis, we were able to manoeuvre the roaster onto the tail-lift.. and then pressed UP.. the Luton’s back-end sank lower and lower and strained against the weight .. and nothing happened. 500Kg maximum working load was clearly not enough.
Time to strip off as much as possible without having to undo the complex wiring, hoping it would be enough. It was. Second attempt was a success as long as no-one stood on the tail-lift and went up with the roaster. Hhhmm, a tricky moment. 500Kg of roaster (and pallet truck) being ‘supported’ by 4 people with outstretched arms. It went up and was safely strapped into the centre of the van and hopefully secure enough to make it to its new home in Brighton
They have given a very fitting name to their new roaster - Elizabeth. Long may she serve them.
The Monday after a an extra long public holiday weekend was always going to be a risky day to try and coordinate the delivery of our new Loring. The stress began the Wednesday before (the last working day before the weekend) when the haulage company sent me an email to say they couldn’t deliver Monday since they didn’t have a suitable vehicle (with a Moffat fork-lift.. required for unloading the crate). The earliest they could get one was Wednesday. This was booked weeks before and paid for in full and at no point was it mentioned it might be a problem, so this came as something of a shock. The haulage company suggested I try and borrow a fork-lift from a neighbour ! Yeh, right. The problem with a Wednesday delivery was that I had booked the Loring installation and commissioning engineer (Malcolm) for Monday through to Thursday and he needed to be elsewhere on Friday morning for another job, before leaving the UK for a months worth of work at various sites in Europe. It had to be Monday.
Malcolm came up with a potential solution. Phone around plant hire companies and see if I could hire a tele-handler for the day (basically a JCB with forks on the front). I was incredibly lucky to find one available for a Monday hire and doubly lucky to be speaking to someone I knew (by chance) who went the extra mile to help (thanks Sarah). So, JCB booked for a Monday 8am delivery, haulage company booked for a Monday 10 am delivery and Malcolm arriving somewhere in between after a 5hr drive. Gotta love a plan.
The timings didn’t quite match but everything arrived within a 15 min window of each other. The first job was to unload the two Loring crates from the lorry using the tele-handler. Malcolm handled this unwieldy looking thing like a seasoned pro. I wish I’d had someone take a video of the whole thing - unloading the large 1300Kg Loring crate off the vehicle and up the steep street then manoeuvring through the roaster doors with Jack and I supporting from either side in case it wanted to topple off the forks ! Next was uncrating the roaster. Lowering one side of the crate was our first glimpse of this shiny beautiful piece of engineering. Once again Malcolm deftly controlled the tele-handler to remove the Loring from its crate. Little this way, little that, lift here, back a little, lift more etc etc. It was quite a thing watching someone being so careful and skilful caressing this beautiful machine out of it’s box and into position.
I’d met Malcolm a few times over the years at various shows and had spoken to him about the Petroncini when I first bought it back in 2013. He’s something of a legend in the industry and has an incredible reputation for being a master of his craft. No wonder Loring won’t allow any one else in the UK (and parts of Europe) to install and commission their machines.
That was a productive Monday morning done. Then Malcolm started the work of installing the new hot stack (the old one wouldn’t withstand the 800C operating temps of the Loring), matching the cold stack to the leftover flue to re-use the old hot stack (as the new cold-stack), electrics, gas, water etc. Everything done carefully and methodically. No rushing, no bodging, everything neat, tidy and professional. Wednesday lunchtime came and then we were ready to turn the Loring ON. Quite a moment. One of the many (big) differences between the Petroncini and the Loring is that Loring is a modern piece of engineering with safety switches, cut-outs, alarms and warnings that just didn’t exist on a machine from 1995 (Petroncinci or any other manufacturer for that matter). As the control panel came to life an audible alarm went off and a message in RED appeared on the screen saying that there was a problem with the incoming gas pressure and it could not ignite. Malcolm explained this was likely due to the gas pipes having some air inside since they had been left open to the air after the Petroncini had been disconnected (makes perfect sense). Clear the alarm, check the pressure gauge and try again…and again…until a successful ignition after 5 attempts. HOUSTON WE HAVE LIFTOFF !
The operation of the Loring is very very different to the Petroncini. It feels a little disconnected, using a touch screen to adjust the burner input as opposed to the old 3-turn potentiometer that felt so intuitive. The screen is full of information that seems a little overwhelming right now. The screen is just displaying information from the PLC (programmable logic controller) which is the brain of the machine. One of the main differences in operation of the Loring compared with most traditional drum roasters is the fact that it’s a closed system which recirculates the exhaust air (after cleaning in the incinerator) ie. It doesn’t continually heat up ambient air. This means that there’s a crucial safety procedure that’s performed everytime the burner attempts to ignite. It purges the residual air/gases from the system by increasing the circulation fan to 100% and opening a purge gate to allow ambient air in temporarily.
As part of the commissioning process we needed to ‘season’ the machine to pull out any metal dust left over from manufacturing, leave a light residue of coffee oils on the contact surfaces and flush the hot and cold stacks with working temperature gases to test the seals and junctions. I’d read about this before with new roasters but never had to do that with the 1995 Petroncini.. quite the opposite in fact due to its misuse by its previous owners (it seems they burnt coffee as their daily routine, whilst we only had to do it once). It’s a process requiring you to waste a batch of coffee and ideally you’d want to use something old and faded and way past its best. We run a pretty lean roasting operation due to our size and by the nature of the quality of the coffees we buy so wasting 5Kg of good green coffee felt a little uncomfortable. But needs must, so our first roast on our brand new machine was intended to roast it very very dark and then keep going. Beyond 2nd crack and up to a point where the cellulose structure has become so brittle that the oils have already migrated to the surface. We dropped it into the cooling tray and were immediately hit by very unpleasant burnt aromas. Black and shiny and very very smelly. Not a nice sweet caramel smell, more like a tin of tuna.. fishy as it cooled indicative of those oils oxidising and turning rancid and due to the development of the compound Ethylmethylamine with extremely dark roasts (ammonia/fishy aromas). A little reminiscent of walking into a Starbucks and the reason that company has a little nickname of Charbucks in the industry.
So now it was time to try and roast properly and I imagine felt a little like getting out of a 1970’s Ford Escort into a brand new Tesla (just guessing of course). The first two batches were a little sketchy and that coffee won’t be seeing the web-store. Then it was time to do some production roasts of coffee we know and have on our offer list. The old profile curves off the Petroncini are almost irrelevant.. almost. The temperature readings at which things happen are going to be different due to the thermocouples, their responsiveness, their placement etc. The time has some relevance however and if you know a coffee tasted good at 9’30” overall roast time on the Petroncini then that’s a good starting point to get to. That’s not to say it would be perfect or even as good since it’s not just the destination (end temp and time) but the journey (how you get there) that counts. The only way really to tell is cup them side-by-side and blind (not knowing which one is which rather than actually being blind-folded). Difficult since the Petroncini coffees were roasted a full 7 days before-hand, so the comparison wasn’t straightforward. In all cases the Petroncinci roasts tasted better which shouldn’t have been a surprise with 8 years worth of machine operating experience versus an hour or so. Then it’s a matter of working out what changes need to be made to the new Loring profiles for those coffees and implementing them. Easy eh !
Malcolm signed us off as ‘proficient’ operators and off he went to his next job. Thank you Malcolm.
It’s going to require a little getting used to.. working out best practice and procedures for our roasting style to get back to the level of proficiency we were at previously. Then we can start to explore some of the advanced features of the Loring to enhance consistency and productivity.
Here she is in her space.
Say hello to Loretta.
