Kuusi T, Pyysalo H, Pippuri A
Z Lebensm Unters Forsch. 1977 Mar 21;163(3):196-202. doi: 10.1007/BF01459857.
The effect of iron(II), tin(II), aluminium(III), and chromium(III) on the properties of red whortleberry, blackcurrant, and red beet juices was followed during storage for 10 months at 5 degrees C. The colour and pH changes were studied, and the precipitates formed were weighed and their metal contents assayed. Of the metals tested, only tin caused bluish discoloration in the berry juices. In the case of iron, aluminium, and chromium the low pH prevented this type of discoloration. In berry juices, some increases in colour intensity took place with the lowering of pH value, whereas in red beet juice the opposite change occurred. The colour changes due to storage appear to take place irrespective of the metals. Precipitation is enhanced in red whortleberry juice only by tin, and in blackcurrant juice by tin and iron. In red beet juice, precipitation is increased by the lowering of pH resulting from metal salt addition. In general, increase in the amount of metal added increased the metal content of the precipitate. Iron showed the greatest tendency to become bound in the precipitate, particularly in blackcurrant and red beet juice. The suitabilities of the metals for canning purposes are considered. Chromium, in particular, has interesting possibilities in view of the low degree of colour change associated with it.
在5摄氏度下储存10个月期间，研究了亚铁、亚锡、铝（III）和铬（III）对红越橘、黑加仑和红甜菜汁特性的影响。研究了颜色和pH值的变化，对形成的沉淀物进行称重并测定其金属含量。在所测试的金属中，只有锡会使浆果汁出现蓝色变色。对于铁、铝和铬，低pH值可防止这种变色。在浆果汁中，随着pH值降低，颜色强度会有所增加，而在红甜菜汁中则发生相反的变化。储存引起的颜色变化似乎与金属无关。只有锡会增强红越橘汁中的沉淀，锡和铁会增强黑加仑汁中的沉淀。在红甜菜汁中，添加金属盐导致的pH值降低会增加沉淀。一般来说，添加金属量的增加会提高沉淀物中的金属含量。铁在沉淀物中结合的倾向最大，尤其是在黑加仑汁和红甜菜汁中。考虑了这些金属用于罐装目的的适用性。特别是铬，鉴于其相关的颜色变化程度较低，具有有趣的可能性。
