Influence of rapeseed meal on lard stability

摘要

The experiment focused on the possibility to utilise the antioxidant potential of rapeseed meal to stabilize fats. The lard, which was used for this purpose, was characterized by gas chromatography. At first the non-sieved meal was added in lard. It is the least technologically difficult method of utilizing meal. Then, the meal was sieved to obtain five fractions, which were added to lard. The aim was to find a fraction of meal that would best stabilize the lard. The results of lard stability with added fractions were compared with the stability of lard enriched with non-sieved meal. Finally, we obtained ethanol and ethyl acetate extracts from non-sieved meal and from the fraction which was the best stabiliser of lard. The aim was to study the effect of these extracts on the stability of lard.Rapeseed meal has stabilized the lard already at 0.5 wt. % content. The non-sieved meal addition of 1, 2 or 4 wt. % has improved the stability of lard by 1.2-2 times. Adding 8-15 wt. % of meal into lard has increased its stability by 3-8 times. The best lard stability has been determined in the fraction retained on the sieve with mesh size 0.15 mm. The lard with added sieved meal has gained a comparable stability the same as after addition of non-sieved meal. The lard with the same additions of extracts (ethanol and ethyl acetate) from non-sieved meal and from meal with sizes 0.15-0.315 mm was more stable than the lard with addition of meal alone. The lard containing ethanol extracts (0.5 wt. %) has a better stability than the lard containing butylated hydroxytoluene (0.02 wt. %).