Zvi Howard Wener
Chief Agronomist
Zvi@zeraim.co.il

Taste and flavour in tomatoes are perceptions of the taster and are influenced by several factors. These are: sugars for sweetness, acids for sourness, sugar-to-acid ratio, volatile compounds for aroma and the texture of the solid portion of the flesh. It is the interaction of these factors that contributes to taste and flavour. Taste can be said to be good, bland, tart or tasteless. Taste is very subjective and personal, so methods - such as measuring Brix-TSS and EC (electro-conductivity) and panel tasting - have been devised to obtain more objective and quantifiable results. A good tasting tomato will have the right combination of high sugars and high acids together with good aroma and texture.

The taste of a tomato can be improved by genetics and/or environmental factors including agro-technical techniques. There is a direct relationship between taste and the fertigation methods (salinity) used during the crop cycle, the day length and the quantity of solar radiation available for photosynthesis. For example, high salinity causes stress to the plant, increasing sugars and acids as well as improving texture, color and firmness. High solar radiation during fruit growth will contribute to higher sugar content in the fruit, as will higher levels of Potassium. However, if the salinity or stress is too high, fruit quality will be reduced and the taste will become too acidy and sour. Similarly, if the fruit itself is not well protected from the sun’s rays, there can be a deleterious effect on the fruit. For a tasty tomato, it is recommended to pick the fruit at full red so as to get the highest sugar and acid levels and, hence, the fullest flavour.

However, it is very difficult and risky to depend solely on agro-technical techniques for a good taste tomato. These same agro-technical techniques, when applied to the new hybrid taste tomatoes from ZG, will consistently yield excellent tasting and top quality fruit. Zeraim Gedera has been working during the last decade to improve the sugar level and sugar profiles in tomatoes. This work is done in collaboration with the Volcani Center and is led by Dr. Moshe Bar and Dr. Ari Schaffer. The program has started to generate new products (varieties) that are being tested at different locations
throughout the world. These new hybrids are the result of many years of traditional breeding and help eliminate most of the uncertainties of growing for taste and flavour. These taste hybrids include:
TT-30194, a cherry for cluster harvest / TT-30166, cocktail size for cluster harvest / TT-30197, larger cocktail for single pick / TT-40203, small-fruited for single pick or clusters with 3-4 fruits / TT-40211, small-fruited for single pick. It is the combination of unique genetics and good environmental factors that result in our taste tomatoes having a good sugar/acid ratio, high TSS and very good firmness and shelf-life.