Vol. 6 No. 1 (2023): The Reality of Women in Science

• Leke, L.
  Chemistry Deapartment, Benue State University
  https://orcid.org/0000-0002-1748-2400




• Bembur, K.
  Center for Food Technology & Research, Benue State University, Makurdi
  

Pretreatment of tomatoes into powder reduces spoilage andpostharvest loses; however, maintaining the nutritional qualityof the powder poses a challenge. Thus, a quantitative approachwas employed to measure the effect of some pretreatmentmethods of making tomato powder, where fresh tomatoes wereblanched and exposed to different pre-drying treatments(untreated, treatment with 2% NaCl, 2% CaCl and 0.25%Na2S2O2). These samples were then oven dried at 60oC for 8 hbefore blending to the various powders. The proximateparameters (ash, fibre, protein, CHO, fats, moisture), physicchemical, antioxidants, colour and microbial parameter of thepowder samples were then determined over a duration of 3months. Results of the study showed that oven drying andchemical pretreatment significantly increased the nutrientcomponent of the tomato powder and decreased cfu/g ofbacteria, which could enhance the shelf life of the product.The antioxidants properties such as lycopene, B carotene,Vitamin C, and colour were significantly retained withchemical pretreatment. All pretreated samples retained morenutrients and reduced microbial load of tomato powder. Thatof Na2S2O5 retained more nutrients while CaCl2 retained moreantioxidant properties. The NaCl treated powdered samplesretained more ash and total fiber. Similar observations weremade for antioxidants properties. L*a*b values of colour werehigher at month 0 and lowest at month 3, this implies that atmonth 3, traces of undesired colour change began and as such,storage beyond this time may be unhealthy. Also, at month 0,Na2S2O5 retained higher values of colour (L*a*b) whereas CaCl2retained more at month 3. There was a gradual increase in thebacteria and fungi load as the storage period increased. Thepre-drying treatments adopted showed potentials to enhancethe quality and shelf life of tomato powder although may notbe encouraged beyond 3 months of storage.

Keywords: Tomato, chemical pretreatment, oven drying,powder, proximate, antioxidants, shelf life