Influence of Storage Temperature on Chemical

Effect of storage conditions on yeast and mold count

However, the temperature as well as intervals of storage

The changes in yeast and mold count (cfu/g) in pumpkin

individually had significant (p<0.01) influence on the

powder during storage at different temperatures in

retention of carotene in pumpkin powder.

metalized aluminium pouches are shown in Fig. 3. The

Storage stability of pumpkin powder

yeast and mold count also showed a decreasing trend

during the entire period of storage at both the storage

The results confirm that the microbial quality of the

temperatures. Lower the temperature of storage faster

pumpkin powder remained good even after the storage

was the rate of decrease of yeast and mold count. For

for 180 days, both at the temperatures of 7°C & 30°C.

example, at 90 days of storage, the yeast and mold count

However, there was gradual reduction was observed

at 7°C and 30°C were 13 and 25 cfu/g, respectively.

in the carotene content of the pumpkin powder during

But, at 180 days of storage the yeast and mold count at

storage. Though the loss in carotene content was high at

7°C and 30°C were only 7 and 20 cfu/g, respectively.

30°C storage temperature, it was only 17% at the end of

This was probably because of the fact that the optimum

180 days of storage at 7°C. These samples were stored

temperature for growth and survival of yeast and mold

in dark chamber and maintained at 80 and 62% RH,

is between 20 and 30°C. Hence the rate of decrease of

respectively.

yeast and mold count at 30°C is lower as compared to

The carotene degradation was faster when the pumpkin

that at 7°C storage temperature. The above results are in

powder was stored at 30°C as compared to that at 7°C.

good agreement with the results reported by several other

The carotene content in the powder after 30 days of

investigators (Khamrui and Pal., 2003; Adu- Gyamfi.,

storage at 30°C was similar to the value after 90 days of

2006).

storage at 7°C. Carotene content in powder after 75 days

of storage at 30°C was similar to the value after 180 days

of storage at 7°C.

Pumpkin powder was found to be more stable at 7°C

temperature of storage as compared to that at 30°C. The

powder can be safely stored at 7°C for almost 180 days.

Alternatively, at 30°C, the pumpkin powder should not

be stored for longer period than 75 days.

Conclusion

Duringstorageofpumpkinpowder,thestoragetemperature

and period had a significant effect on carotene retention

in the product. As the storage period was increased

Effect of storage conditions on coliform count

from 0 to 180 days, the carotene retention was found

to decrease. More carotene could be retained (82.95%)

During the storage of pumpkin powder at different

when pumpkin powder was stored at 7°C as compared

temperatures, it was found that the coliform which were

to 52. 28% retention at 30°C when the stored for 180

absent initially remained absent throughout the period

days. Standard plate count of powder stored at 7°C was

of storage (180 days). Absence of coliform during entire

found to be only 440 cfu / g at the end of 180 days of

storage period at both the temperatures indicates that

storage. Similarly, yeast and mold count observed at the

hygienic conditions were maintained during preparations

end of 180 days storage was only 7 cfu/g. Coliform was

and further no toxins are produced in the pumpkin powder

found to be absent throughout storage. Pumpkin powder

during storage.

was found to be more stable upto only 75 days, if stored

Statistically, temperature of storage had significant effect

at 30°C. However, it can be safely stored for almost 180

on SPC and yeast & mold count during the storage.

days, if stored at 7°C.

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