Revealed: Aristocrat's original drawings for Quality Street sweets and why he wanted the Purple One, the Toffee Penny and the Green Triangle to be a 'sensory feast'

• Original notes and drawings detailing plans for the first assortment of Quality Street chocolates emerged
• Handwritten  annotations by creator Lord Harold Mackintosh give insight into the origins of the treats
• He wanted to create a 'sensory feast' from the taste right down to how the wrappers felt to touch

For many of us the distinctive purple tin is a stalwart of the festive period - bulging with treats to be nibbled and squabbled over during Christmas.

Now, original notes and drawings detailing plans for the very first assortment of Quality Street chocolates have emerged - revealing their creator always intended the 'special container' would become 'a much sought after biscuit or cake tin.'

The previously unseen scribbles show the thinking of celebrated confectioner Lord Harold Mackintosh - great-grandfather of Made in Chelsea star Millie Mackintosh - who wanted to create a 'sensory feast' right down to how the wrappers felt to touch.

In one memo dated 19 November 1935, he wrote to a Mr E Fletcher, senior manager at one of his factories, asking for his opinion on how each sweet should be individually wrapped, and whether waxpapers, foils or cellophane should be used.

He asks Mr Fletcher for his 'very careful judgement' and seeks his thoughts on how many of each chocolate should make up every assortment.

On December 12 1935, he wrote an eight point 'Plan for Quality Street' from the point of production to selling tins in shops, while a later note reveals how he tweaked the names of every sweet.

The company has released the notes 80 years on from launching the celebrated tin of chocolates, revealing five of the original sweets remain today.

Company historian and archivist Alex Hutchinson discovered the documents stored in the Borthwick Institute at the University of York.

She found Lord Mackintosh - who later became 1st Viscount Mackintosh of Halifax largely through his fundraising efforts in World War Two - had hand-drawn how he wanted the individual sweets to look.

Lord Mackintosh, who was knighted aged 31 for his work in Sunday Schools, was also motivated by the idea of making an affordable tin of chocolates for anyone to enjoy, as the price of cocoa was high in the 1930s.

Ms Hutchinson, 34, said: 'With this assortment, he really wanted to create a sensory feast, and not just something nice to eat.

'He wanted it to be an explosion of colour and aroma, with different types of wrappers and an exciting experience when you open the tin.

'He wanted it to be really, really special, but at an affordable price. With a mix of toffees, they were able to make it so much more affordable.'

The notes reveal the original assortment had 18 different sweets, compared to the present day 12 - but some familiar favourites remain today.

These include the Toffee Penny, Toffee Finger, Green Triangle, Caramel Swirl and The Purple One.

Lord Mackintosh's close attention to detail is highlighted in notes written on February 19 1936 - less then three months before its launch - titled 'The Container'.

He wrote: 'So great a line deserved something very special in containers and this has been most carefully designed.'

He then wrote a three point plan, adding: 'First and foremost, as a practical container - one which is easy to serve from, occupying the minimum of room - and which will keep its contents in the very best of condition.

'Secondly; from an artistic standpoint, a design that has the hallmark of quality written all over it - a design that is distinctive - a bright clean design that is in itself inviting.

'Thirdly, a container that will be useful in the home and this will be a much sought after biscuit or cake tin.'

He wrote that a 'line of such high quality deserves and demands quality in presentation', adding: 'Compelling attention and at the same time emphasising that here is something new and important.'

Over the years the assortment - originally seven toffees and 11 chocolates - has chopped and changed, with the popular favourite Toffee Deluxe controversially withdrawn this year.

A new sweet was added in its place - the Honeycomb Crunch - which was the first addition since Nestle brought in the Milk Chocolate Block in 2007.

The first assortment was produced in 1936 in Halifax, where the sweets are still made.

Lord Mackintosh named the assortment 'Quality Street' after playwright and Peter Pan creator J. M. Barrie's renowned play of the same title, to reflect the selection's high quality ingredients and presentation.

Ms Hutchinson said: 'This is the first time anyone has seen these records, and we're excited to be sharing them for Quality Street's 80th anniversary.

'They show just how much thought went into the original assortment, and how Lord Mackintosh was concerned with the same things we are: great sweets, made from great quality ingredients, in beautiful wrappers and a tin or tub you'd want to keep.

'It's fascinating to see how the assortment has evolved over the years, but stayed true to the Mackintosh's original idea.'

Jon Smith, the brand's manager, said: 'For many families sharing a tub of Quality Street has become a Christmas tradition.

'Long may this tradition continue for the next 80 years.'

Lord Mackintosh, whose mother created the chewy toffee sweet, was the owner of the confectionery business of John Mackintosh & Sons Ltd from 1920, when his father died of a heart attack.

To launch Quality Street, he had a full page advertisement on the front of the Daily Mail on May 2 1936.