4. Conclusions
The addition of SO2 and pectolytic enzymes to the substrate
increased AA, TPI and TA.
Although the cooked must vinegar presented the highest AA and
TPI values, this substrate must be discarded for the strawberry
vinegars production at an industrial scale because of their obtaining
process is very slow and complex.
Concerning the acetification stage, the use of wood barrels was an improvement in all of the parameters determined; specifically, cherry barrels were the best to produce
high antioxidant strawberry vinegars rich in phenols.
The most appropriate final treatment was the pasteurisation with reference to
AA. All measured parameters decreased during the double
fermentation process.
In general, acetic fermentation was associated with higher decreases in AA and polyphenols than alcoholic fermentation, except in the semi-pilot scale case.
Moreover, anthocyanins were severely influenced by this process.
So, for substrate selection the parameter more important to take into account is the
TA content.
We also noted that the production of these vinegars on
a semi-pilot scale resulted in final products with the best antioxidant
properties and phenolic content.
The antioxidant properties of these vinegars point to them as products with potential health benefits that could make them competitive commodities in the market.