Milk-crumbs

Milk-crumbs and soya-crumbs are new aroma sources produced by the Maillard reaction and intended to be used in the food industry. During the production of the crumbs thermal reactions take place in the material (e.g. milk) and the added glucose and amino acid constituents. Fructose-lysine and... 

Material and Supplies Milk-crumb and soya-crumb were prepared by the KANOLD AB Co., Goteborg, Sweden. N-((-acetyl-L-lysine. A Grade, Calbiochem. 

Test for Mutagenic Activity Milk-crumbs and soya-crumbs extracted in two different ways were tested for possible mutagenicity by the Ames test. 

Table I shows the furosine content of the milk-crumb and soya-crumb samples in comparison to other food protein sources thermally processed. Milk—crumb has the highest furosine content, probably due to the free lysine and glucose added in the production moreover, the milk protein has also a considerable level of protein-bound lysine.

Among the values given in the Table I only milk crumb and the whipping agent have furosine levels that can be compared to the fructose-lysine (or lactulose-lysine) content used in Erbersdobler s experiment. 

The test for mutagenic activity of the detergent (Tween) extract did not induce any revertants all plate counts were in the range of spontaneous mutation rate, with and without S-9 mix. From the ethanol distillate we got a positive response demonstrated in Table II. In the case of milk-crumb the numbers of induced revertants were about a hundredfold those of the spontaneously reverted colonies with the most sensitive strains (TA 98, 100) only without metabolic activation. In the same experiment the test strain TA 100 responded to the soya-crumb sample, also only without metabolic activation. 

Our experiments on the antioxidative effect of soya-crumbs are summarized in Table III. Surprisingly milk-crumb had no effect at any pH value, although the opposite could be expected from its high level of Amadori products. 

Milk-crumbs and soya-crumbs belong to this group. Their favorable organoleptic characters and good adaptability to further technological processes have been established, but more scientific investigations are still needed. The analysis of the aroma constituents of the crumbs is a task for the future. 

The potential toxicity of the Amadori products (e.g. fructose-lysine) is still uncertain. The high levels of furosine in the milk-crumb add to the need to settle this question. 

The model experiments on the antioxidative effect of crumbs revealed the potential ability of the soya-crumb to prevent lipid oxidation in certain foods. The mild acid medium of meat products seems to be favorable for fulfilling this hope. However, further investigations in food products are necessary to obtain a decisive answer. As the case of milk crumb shows, a Maillard product is not necessarily an antioxidant. 

Milk-crumb D-fructose- and D-lactulose-lysine as 2FMAA 4 g /100 g protein [24]... 

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