This study investigated the microflora on fresh ginger (Zingiber officinale Roscoe) rhizomes and ginger powder in Nortehrn Cameroon with the aim of (1) identifying ginger producing locations with the best quality fresh ginger in terms of low bacterial and fungal load and (2) developing the best processing techniques to ensure low counts of microorganisms in the ginger powder. Thirty-six (36) rhizome samples were collected, and samples of powder were produced using four different treatments. All rhizome and powder samples were analysed for total colony counts of bacteria, yeasts and moulds. The total colony counts of bacteria were higher (x109 cfu/g) than those reported in the literature (x106 cfu/g). The colony counts of all microorganisms for the rhizomes were significantly different (P<0.05) across locations and in different sites within the same locations. Total colony counts of microorganisms in the powder indicated a reduction of 3 log cycles for bacteria (x109 to x106cfu/g); and 2 log cycles for yeasts and moulds (x106 to x104cfu/g) compared to the counts in the rhizomes. Some processing treatments had similar average total colony counts of bacteria (raw oven dried, 7.31 x 106 cfu/g and heat-treated sun dried,7.48 x 106 cfu/g); and yeasts and moulds (raw, sun dried 7.72 x 104 and raw oven dried, 7.68 x 104 cfu/g; (P>0.05)), while others were significantly different (P<0.05) (raw sun dried,4.32 x 106 cfu/g and heat-treated oven dried,9.98 x 106 cfu/g for bacteria; and (heat-treated sun dried,5.85 x 104 and heat-treated oven dried1.25 x 105 cfu/g for yeasts and moulds). The best ginger rhizomes were produced in Bafut and Mbengwi locations. There was general reduction of microbial counts on processing the rhizome into powder. The best processing techniques were slicing and sun drying without heating for bacterial counts, and slicing, heating and sun drying for yeasts and moulds. The results of this study will be useful to people involved in ginger cultivation, processing and utilisation as a spice or ingredient in food formulations and marketing especially exportation from the North-West Region of Cameroon.

Key words
Zingiber officinale, bacteria, yeasts, moulds

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