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Plant Foods for Human Nutrition

, Volume 45, Issue 2, pp 183–189 | Cite as

Microbiological evaluation of tofu and tempeh during processing and storage

  • Mogessie Ashenafi
Article

Abstract

Tofu samples consisting of ‘Fresh Tofu’, ‘Herb Tofu’, ‘Tofu Paste’, ‘Fried Tofu’, ‘Tofu Burger’, ‘Smoked Tofu’ and different types of herbs used for making ‘Herb Tofu’ were analysed for their microbiological load. Tempeh samples consisted of cook water, inoculated beans and fresh tempeh. ‘Fresh Tofu’ and ‘Herb Tofu’ had high bacterial counts (≥105 cfu/g). ‘Tofu Burger’ and ‘Smoked Tofu’ had counts around 104 cfu/g. ‘Tofu Paste’ and ‘Fried Tofu’ had low counts (<102 cfu/g). Cutting board, knife and frequent hand contact with product were the major sources of contamination for tofu. Herbs used for making ‘Herb Tofu’ were highly contaminated (>105 cfu/g). Cook water and cooked beans for tempeh production had lower counts (≤104 cfu/g). Initial count of fresh tempeh was high (about 108 cfu/g). Most products had counts of >106 cfu/g after 7 days of cold storage. The microbiological quality of the product may improve if producers avoid unnecessary contamination during processing.

Key words

Tofu Tempeh Microbiological quality Cold storage Processing 

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Copyright information

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • Mogessie Ashenafi
    • 1
  1. 1.Department of Basic Sciences, Awassa College of AgricultureAddis Ababa UniversityAwassa, SidamoEthiopia

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