As sales volumes increase, Jenny’s Jams have engaged with the COTEMACO SME support programme to improve production capacity and efficiency and reduce physical efforts. The current weekly production is c.1000 units/week, split approximately 75% jams and marmalades, and 25% chutneys. The majority of production is packaged in 3 sizes of glass jars (340g, 220g, 40g) along with small numbers of bulk catering buckets (1 – 2 litre) to order as required.
Current production is a manual batch process. Machinery is used for jar washing, and cooking, but all other processes and manual handling are performed by hand.
The basic production stages are:

1. Fruit/Ingredients preparation (washing, peeling, coring, cutting, etc).
2. Combine ingredients & heat whilst stirring. Jams and marmalades manufactured in 30-50kg batches in a 300L kettle (Figure 1). Chutneys are produced on a stove top in 10L pans (Figure 2).
3. Whilst cooking is proceeding, machine wash enough jars for the batch.
4. Manually hot fill jars, by dipping a jug into the hot (60°C) products and pouring the contents into jars.
5. Manual lidding of jars
6. Machine wash filled jars to remove any spills from the external surfaces.
7. Allow to cool in store.
8. Manually apply product and BBE labels.
9. Store ready for dispatch.

The jam/marmalade cook up process takes 45-60 minutes per 50kg batch and once ingredients are added the cooking process is automatic with the kettle control system performing stirring and temperature control. Jars are pre-washed in trays of 40-42 taking 2- 3 minutes for each tray. A tray of pre-washed jars is brought to a working table close to the kettle and the operative reaches into the kettle with a jug to scoop out hot product and manually fill each jar. Lids are screwed on manually and this is repeated until all jars in the tray are filled. The filling and lidding takes between 9.2s – 12.3s per jar, with a mean of 10.7s. The tray of lidded filled jars is carried to machine wash the outsides and fresh tray of prewashed jars is collected. This cycle is repeated until the entire production batch in the kettle has been jarred, lidded and externally washed. These processes require substantial staff movement around the production space (Figure 3).
The chutney jarring process is similar, but batch sizes c.10kg are substantially smaller.

The same rationale applies to the large 300L kettle for jams where currently a 50kg batch has a mean overall rate of 34s / jar. Using batch sizes of 100kg, 200kg, and 300kg and allowing for a 25% increase in prep and cook times would give mean overall rates per jar of 24s, 20s and 19s respectively. However, the physical stresses of manually filling each jar by jug and hand screwing of caps would increase substantially with larger batches. The use of depositor automation would decrease the repeated stresses of reaching into the kettle for each jug-full, produce faster fill times, and potentially reduce splashes on the outside of jars potentially removing the need for the jar outside washing process.
A benchtop depositor is the most appropriate size for current production. This would be mounted to allow a trolley to pass under the nozzle outlet. The jars would be kept in the dishwasher trays (or the smaller blue crates) to move many at once and reduce handling. The weight of the tray of jars during filling would be supported by the trolley and moved manually to place jars sequentially beneath the nozzle and then triggering each fill with a foot switch. This is expected to reduce mean fill time per jar from c.10.7s to c.5s, resulting in a c.52% increase in filling rate per jar, and a c.16% improvement in overall rate per jar taken across an entire 50kg batch. Investment cost for depositor would be c.£4k to c.£12k. The particulates of fruit in the products poses an additional challenge and practical trials will be required to determine if a specific depositor can deal effectively with the full range of products. A revised layout with depositor is shown in Figure 4.

A handheld pneumatic lid tightener could be used to reduce repetitive strain injury (RSI) risk to wrists with the increased numbers of lids needing tightening. Whilst there are no direct speed improvements, the cost (c.£900) could be justified under health and safety as RSI risks are reduced.
Alongside the depositor itself is the challenge of safely getting hot product from the kettle into the depositor hopper. In the short term a large jug could be used but this requires reaching into kettle and lifting to tip into the hopper. At later stages using a transfer pump to ease this process however to cope with the particulates in the jams/marmalades/chutney process start at c.£11k.

At the time of writing, Jenny’s Jams are considering the automation roadmap and preparing to implement initial stages. Further steps will be reviewed and implemented as time progresses and the enterprise grows. Business growth will be both the driver and financial enabler for adoption of further automation including cobotics.
The main opportunity for cobotics occurs later in the automation roadmap to remove the tedious and repetitive jar handling operations between process stations. This approach integrates with previously implemented process units that were manually loaded and unloaded in earlier automated process configurations.