Abstract:
Tomato (Lycopersicon esculentum Mill.). is an important fruit and an excellent source of nutrients,
including vitamin C and dietary fiber. Quality characteristics of tomato varieties and related
products have been studied in almost all major tomato-producing countries around the world.
Tomato paste is commonly produced by the hot-break processing method: a rapid deactivation of
pectolytic enzymes during the hot-break process is considered essential to prevent demethylation
and breakdown of pectin molecules. This, study was initiated to determine the effect of varieties,
lemon juice and storage temperature on the physicochemical, sensory evaluation, and microbial
load of tomato paste in Ethiopia. The treatments consisted of three varieties of tomato (Galilea,
Gabby & Anna) two lemon juice concentration (5&10) % and three storage temperatures (4, 14,
and 24 °C). The experiment was laid out a completely randomized design in factorial
arrangements (3x2x3) with control (3) samples=21 treatments) with triplicates. The result
revealed the physical properties of the three fully ripened tomato varieties. Tomato variety, lemon
juice and storage temperature had a highly significant effect (P<0.01) on the physicochemical
properties of tomato paste (i.e., total soluble Solid (oBrix), titratable Acidity, pH and vitamin C
ranges with treament was (28.00 -22.30 %) (V1L1T1-C1), (1.24- 0.70) (V1L1T3-C3),(4.46-
3.36(V1T1T3-C1) (25.10-16.26) g/100g )V1L1T1-C3)). In addition, V1L1T1 tomato paste that was
treated at 5 % lemon juice concentration was mostly preferred by the panelists. From the total
bacteria, yeast and mold growth in each treatment, the tomato paste was microbiologically safe
for one and half months at room temperature storage. The most preferred paste by the panelists was
produced from Galilea and Gaby tomato with the treatment of lemon juice 5 % & at 4°C. Generally,
this study concluded that V1L1T1 and V2L1T1 separately could be recommended in the production of
Tomato paste.
Keywords: Hot break, tomato paste, tomato varieties, quality, and sensory evaluation.