NUTRITIONAL VALUE OF MINOR FRUITS IN LATVIA

There are many edible fruits and berries in Latvia, which are still underutilized for commercial growing and processing in food products. Some of them are known for their medical value (e.g., Rosa rugosa and Aronia melanocarpa) or are cultivated in home gardens, but there is little information about nutritional value and suitability of minor fruits for developing products of high nutritional quality. The aim of this research was to evaluate the biochemical composition of minor berries and small fruits grown in Latvia and compare it with antiradical activity of the sample. The experiments were done at the Latvia University of Agriculture and at the Latvia State Institute of Fruit-Growing. Contents of titrable acids, soluble solids, ascorbic acid, total phenols, anthocyanins, carotenoids, tannins, and antiradical activity (DPPH) of fresh and frozen fruits of saskatoon (Amelanchier spicata), honeysuckle (Lonicera ssp.), golden currant (Ribes aureum) ‘Laila’, rosehips (Rosa rugosa), hawthorn (Crataegus submollis), chokeberry (Aronia melanocarpa), black elder (Sambucus nigra), wild rowanberry (Sorbus aucuparia), and red bilberry (Vaccinium vitis-idea) ‘Coralle’ were analysed. Fresh honeysuckle and frozen chokeberries had the highest anthocyanin content, and red bilberry cultivar ‘Coralle’ and chokeberry had the highest total phenol content. Rosehips had the highest contents of carotenoids and ascorbic acid. Chokeberry, rosehips, and saskatoon berry had the highest antiradical activity, and the high antiradical activity correlated with high contents of total phenols (r=0.81). Several of the tested fruits had very high nutritional value (rosehips - high contents of ascorbic acid, phenols, caroteoids, and high antiradical activity; chokeberry - high contents of phenols, anthocyanins and high antiradical activity; saskatoon berry - high contents of anthocyanins and high antiradical activity; honeysuckle - high contents of anthocyanins and phenols). Most of these berries have to be evaluated for stability of nutritional value in different products and, finally, new products developed for enlargement of a healthy food assortment.