J SAINSBURY PLC 
- New research shows the Zari apple is key to bobbing success this Halloween
- Leading mathematician calculates the perfect apple dimensions
- Hundreds of dedicated bobbers test out the perfect variety at a giant apple bobbing event in Bloomsbury Square Gardens in London
With just a few days to go before the nation prepares for Halloween, Sainsbury's has enlisted the help of UCL mathematician, Frank Smith, to help give competitive apple bobbers the winning edge this year.
After a series of complex equations, the British grown Zari apple has been identified as the perfect variety based on its size, shape, buoyancy and texture.
Having calculated the average Brit's mouth size when open and ready to bite - Professor Smith's formula uses mouth size and texture to identify the ideal circumference, diameter and weight of the apple.
The mathematical equation for the perfect apple is:
D = 3× (2 + T 2) × M / (10 ×T)
(D = diameter/T = typical texture of an apple which has a medium value of 0.360/ M = average mouth size)
For those left scratching their heads by the boffin's equation, Sainsbury's reveals bobbers should be using a Zari apple if they want an edge over the competition this Halloween.
Professor Smith claims this variety has the optimum buoyancy in water, texture and density, as well as the perfect amount of exposed surface area, enabling bobbers to snatch the apple with maximum speed and efficiency.
Professor Smith commented: "Apple colour may not matter in itself but the skin toughness or texture is critical. A soft skin can lead to excess bouncing and therefore less efficient bobbing, while a hard skin may mean the apple is difficult to bite into. Given the harmony of all these essential characteristics - the Zari is undoubtedly the perfect apple to bob with!"
Lee Turner, Apple buyer for Sainsbury's said: "We're in the middle of a bumper British apple season so it's the perfect time to be buying your Zari apples for Halloween.
"We've always been proud of the quality and variety of our British apples but it's great to see that of the 51 varieties of British grown apples we sell at Sainsbury the Zari apple is getting the recognition it deserves now its proven to be perfect for bobbing this Halloween."
Putting their money where their mouth is, hundreds of bobbing enthusiasts headed down to Bloomsbury Square Gardens yesterday to put the science to the test.
Notes to editors
- Sainsbury's reveals bobbers should be using an apple with a diameter of 66.80mm, circumference of 210mm and weight of 148g if they want an edge over the competition this Halloween. Based on the average size, this makes the British xxx apple the perfect bobber
- Professor Frank T Smith, PhD, FRS- Goldsmid Professor of Applied Mathematics was also responsible for the mathematical formula for the perfect stone skim
- Sainsbury's Concept Orchards were developed as a way to help halt the decline of the British apple and pear orchards. We are using these orchards to develop new varieties and increase yields through new and innovative growing practices.
- By 2020 Sainsbury's is set to double the amount of British food sold.
- By 2020 Sainsbury's will source all key raw materials and commodities sustainably to an independent standard.
- Zari apples are available in selected Sainsbury's stores, sold as both loose and pre-packed apples
Sainsbury's stocks over 50 varieties of home grown apples
- Royal Gala
- Braeburn
- Cox
- Kanzi
- Jazz
- Rubens
- Tydemanns Early Worcester
- Delbard Estival
- Laxton Fortune
- Lord Lambourne
- Delbard Festival
- St Edmunds Russet
- Kidds Orange Red
- Norfolk Royal Russet
- Regal Prince
- Empire
- Junami
- Laxton Superb
- Red Pippin
- Meridian
- Ingrid Marie
- Golden Delicious
- Egremont Russet
- Charles Ross
- Bennie Shogun Fuji
- Cameo
- Pinova
- Adams Pearmain
- Ashmeads Kernel
- Jersey Mac
- Falstaff
- Katy
- Blenheim Orange
- Ribston Pippin
- Orleans Reinette
- Jupiter
- Winter Gem
- William Crump
- Chivers Delight
- Rosemary Russet
- Arkcharm
- Sunrise
- Discovery
- Windsor
- Worcester
- Spartan
- Empire)
- Cameo
- Jonagold
- Bramley
- Zari
