Effect of sulphur dioxide on microbial growth in refrigerated prepeeled potatoes packaged in plastic films

GIANNUZZI L.; ZARITZKY NOEMI.

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE

JOHN WILEY & SONS LTD

Lugar: LOndres; Año: 1990 vol. 51 p. 369 - 379

0022-5142

Microbial growth in pre-peeled potatoes was analysed to determine the simultaneous effect of sodium bisulphite concentration (105-219 mg kg- ´),storage temperature (4, 7 and 10°C) and gaseous permeability of the packaging plastic film (polyethylene and EVA-SARAN-     EVA used in vacuum) on product storage life.Composition of the microbial flora was determined at the beginning and the end of the storage period, and the principal microorganisms causing spoilage of the product were observed to be Pseudomonas spp and Enterobacteriaceae. Lag phase duration and specific rate constants were determined for these microorganisms in samples stored at each condition. In polyethylene-packaged samples microbial growth was observed at various temperatures and SO2, concentrations were tested. With vacuum packaging in low oxygen permeability films and residues of 100mg SO2 kg -1, microbial counts were maintained in the lag phase; larger residues produced microbial inhibition at 4, 7 and 10°C.