The influence of the color, firmness and processing method of raw tomatoes on the physical, chemical characteristic of tomato paste

Tomato paste is one of the most common products of the tomato and most important Persian food flavors that its production has been increased in recent years. Since human health depends on the quality of processing food, it is necessary to study the quality of this product. The aim of the research is to investigate the effect of firmness and color of tomatoes and processing method on some physical, rheology and chemical properties of Tomato paste is made. For this purpose, color treatments were considered at two levels: between 15-25 and 25-35, firmness treatments were considered at two levels between 0.5-2 N and 2-4 N and processing methods were considered on two levels for hot break and cold break. Acidity, consistency, viscosity, color, Brix and pH Factors of tomato paste were measured. The results showed that the physical and mechanical properties and processing method effect on properties of tomato paste. From tomatoes with a firmer texture and hot break processing method, with more red index paste was obtained. Tomatoes that have redness index lower, consistency and viscosity of paste were higher. The results showed that the soluble solids paste that was processed by hot break is further than cold break method. Tomato paste from tomato category with more firmness and hot break processing method was more acidity. pH of less red tomato paste category and more firmness is more than less red index and more rigid categories.