Effects of sugar- free chocolate containing s1-casein peptide on stress: a survey based on questionnaire data and salivary cortisol concentration measurement

Stress reduction, plays an important role in the prevention of different disorders such as blood pressure, obesity, ulcers, nervousness, problems with memory and etc. Proper lifestyle and healthy diet habits could keep stress under control. Some preliminary researches, demonstrated the effect of food-derived bioactive peptides on stress reduction. The aim of this study was to investigate the effect of daily consumption of 12 g sugar-free chocolate containing 150 mg peptide (aS1-casein (91-100)) on stress reduction in healthy normal-weighted participants. Clinical assessments included self-rated questionnaires and saliva cortisol level, which were recorded and analyzed before and after chocolate consumption for 2 weeks. Sixty participants completed the Cattle Inventory (CI), the Beck Depression Inventory (BAI) and the Depression Anxiety Stress Scales (DASS) questionnaires. To determine the thermal and mechanical stability of the peptide during chocolate processing, FTIR and HPLC were used. Results showed that consumption of peptide containing chocolate reduced anxiety and stress scores in questionnaire and cortisol level in saliva, significantly (P