Effect of added ascorbic acid, amino acids and minerals on browning in Coorg orange juice and squash and model systems at ordinary and elevated temperatures.

In natural Coorg orange juice and squash and also in model systems corresponding to' \nthese, added ascorbic acid is the most important single factor concerned in their browning \nduring storage, and this is already well known. Browning is considerably more in the case \nof lots preserved by pasteurisation than in the case of those preserved with SO.. The \naddition of amino-acid mixture up to 400 ppm does not have any further marked effect on \nbrowning that occurs in the presence of ascorbic acid. Neither the addition of minerals \npresent in the orange nor of the acid hydrolysate of the rag does influence browning to \nany extent. \nIn model systems, autoclaving at 10 lb. p.s.i.g. results in browning of the sugar solutions. \nbrovming being more marked in the alkaline medium than in acid or neutral media. \nExcept in the highly acid (pH 0.65-1.09) and highly alkaline (pH 7.13) ranges, there is \nvery little browning in glucose and sucrose solutions. Among the common sugars, galactose \nis tbe most susceptible and sucrose. tbe least susceptible to browning on beating. In \nthe case of glucose solution, ferrous irOn increases browning, while metallic tin and SO. \ndecrease it.