Rachel's Dairy Limited started as a farm-based business in 1982 and
expanded into a purpose-built dairy in 1990. The company produces a
range of organic dairy products, and is involved in all stages of the
processing of these products, and in the related marketing and distribution.
The company employs 58 people and achieves sales revenues of over 5
MEUR per annum. The industry sector occupied by Rachel's Dairy is defined
by the standard industry Prodcom code 1551 (Food).
The company's product range includes organic yoghurt, crème
fraiche and double cream. Rachel's Dairy supplies these products to
major chain retailers (the supermarkets), and via wholesale distributors
to delicatessens, health food shops, small retail and some catering
outlets. A limited quantity of direct sales are also achieved. The company
uses commercially available food processing equipment to produce these
products, and until the application experiment had no experience in
using or specifying microelectronic products.
The production process for yoghurt requires precise control over the
pH of the milk during the incubation and the subsequent blast-chilling
process. The current manufacturing process at Rachel's Dairy requires
the use of periodic sampling using hand-held pH meters. This method
is inadequate, and operator estimation of the required incubation time
can lead to excessively 'acid' levels of pH in the final yoghurt. The
batch of yoghurt must then be disposed of.
The rationale for the application experiment was to improve the quality
control process by repeatedly monitoring the pH of the yoghurt during
its incubation process to prevent this commercial loss. The improved
monitoring of pH is estimated to result in a reduction in the current
rate of wastage from 3% to 1%.
The technical objective of the application experiment was to replace
the current pH sampling method with a continuous, in-line measurement
and data logging method. The application experiment therefore involved
the development of a microcontroller-based multi-channel pH measurement,
display and data logging system to provide the following functions:
- Monitor pH in yoghurt continuously during the incubation process,
and provide out-of -limit warnings.
- Log the values of pH over extended periods of time, and to transfer
this data to a PC for later analysis.
The duration of the application experiment was 10 months. This was
extended from the 8 months anticipated to allow for the more complex
design undertaken, and the inexperience of the company in developing
specifications which required longer to complete. The prototype development
cost was 38 K EURO, and a further 12 K EURO was required for industrialisation.
The economic impact of the adoption of the improved quality control
process is significant, and will produce not only cost savings but provide
opportunities for increased sales by the development of improved supplier
ratings with the major supermarkets. The projected payback for the combined
prototype development and industrialisation cost is 10 months, and the
rate of return on investment (ROI) in the first four years is estimated