Soya-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... 

The KANOLD AB Company has developed a series of new materials, produced from mixtures of skimmed milk, glucose, and lysine (or other basic amino acids) by drying on a roller at a temperature of 125°C (1 ). Instead of skimmed milk, soya flour can be used as basic material. The new products, named milk-and soya-crumbs respectively, have a very pleasant odor... 

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.

Furosine content of milk and soya-crumb, and of other... 

Soya products contain much less reducing carbohydrate and also lower bound lysine than those from milk moreover, only small amounts of free lysine and glucose were added in the production of soya-crumb. The smaller furosine values from soya products can be explained by these facts. The effect of intensive heat treatment on the formation of furosine is demonstrated by roasted coffee. 

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. 

Soya-crumb has a significant antioxidative effect in the sunflower oil emulsion system, although less than BHT in the concentration generally used in the food industry (Table III). The antioxidative effect is higher in the acid region with a maximum observed between pH values of 4 and 5. 

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 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. 

Crude soya bean oil contains 3% phospholipids with about 35% of this in the form of lecithin (phosphatidyl choline) (10.47). Rapeseed oil contains 2% and Sunflower seed oil -1.5% total phospholipids. Palm oil, another large tonnage edible oil, usually contains hardly any. Phospholipids are present in margarine where they contribute to its special properties (see above). The small phospholipid content of cereal starch is responsible for its function as a crumb softener when added to bread (see below). 

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