Fatty acids, essential amino acids, and chlorogenic acids profiles, in vitro protein digestibility and antioxidant activity of food products containing green coffee extract

The aim of this study was to determine the effect of addition of green coffee extract (GCE) in concentrations from 0.25 to 1 g 100 g-1 on the physical, sensory and chemical properties, and antioxidant activity of some food products. Two kinds of gnocchi (from fresh and dried potatoes), sponge cake, bread, mayonnaise, marshmallows, caramel candies and jellies were prepared. Among supplemented products food with the maximal GCE addition best sensory properties showed mayonnaise, followed by marshmallows and jellies. Addition of GCE caused changes in color of products, where the smallest changes were observed in mayonnaise and gnocchi from dried potatoes (ΔE 1.20 and 2.93 respectively) and the highest in jellies and sponge cake (ΔE 20.38 and 12.80 respectively). GCE added to food products allowed to maintain higher amount of polyunsaturated fatty acids (PUFA), especially prepared with the use of high temperature, such as marshmallows. In this product with 1 g 100 g-1 of GCE the PUFA content was 5.82 g 100 g-1 while in control it amounted 4.55 g 100 g-1. The losses of polyphenol introduced to the food products with GCE were the smallest in mayonnaise and jellies prepared under low temperature. Addition of GCE contributed to the increase of antioxidant activity of enriched products. The highest increase of antioxidant activity was observed in sponge cake, followed by candies, marshmallows and mayonnaise. The losses of amino acids caused by the addition of GCE were greatest in products treated at a moderately high temperature and subject to further gelation, i.e. jellies and marshmallows. Despite higher losses of amino acids the effect of the addition of GCE on protein pepsin digestibility the did not exceed 3%.