High-accuracy, low-shear pumping of salad dressing

At CCL Foods, Earls Colne, Colchester, a Watson-Marlow peristaltic pump handles some fifty different mayonnaises and other vinegar-based salad dressings.

Viscosity of the dressings ranges up to 30,000 cP and the products contain a wide variety of particulate including mustard seeds, whole "mini" capers, kibbled onion, chopped olives, rosemary, chopped horseradish and diced red bell peppers, in varying concentrations.

CCL's Engineering Manager Norman Wiseman stresses that a high standard of volumetric accuracy is vital at all times on the duty which involves filling jars, bottles and catering packs. As well as the pump's ability to cope with both high and low viscosity products without fall off in performance, of equal importance are easy cleaning and a smooth, low-shear, low turbulence pumping action, which obviates risk of the product thinning or damage to particulate ingredients in the dressings.

The Bredel SPX50 replaced air operated diaphragm pumps which had problems when operating at the higher viscosities in this application.

180ml to 540ml capacity jars and bottles and 2 to 6 litre capacity plastics catering packs are filled through an in-line, six head filler, controlled by a Harford weight/volume system. Fill can be in millilitres or, using SG conversion, grammes.

The low shear, true positive displacement action of the SPX50 pump ensures optimum finished quality. At CCL the pump operates at a fixed speed with a two metre suction lift and delivering through a five metre line to a hopper.

More information on Bredel pump range.