Original Article

Effects of sugar-free, αs1-casein–enriched chocolate on stress: based on salivary cortisol measurement and questionnaire data collection


Objective: Some food-derived bioactive peptides have demonstrated positive effects on stress reduction. This study was an attempt to evaluate the effectiveness of daily consumption of 12 g of sugar-free chocolate containing 150 mg of αs1-casein (91-100) peptide in alleviating stress in healthy, normal-weight participants.
Methods: Salivary cortisol concentration and self-report questionnaire data were obtained before and after chocolate consumption. Sixty participants completed the Cattle Anxiety Scale (CSI), the Beck Depression Inventory (BDI), and the Depression Anxiety Stress Scales 21 (DASS-21).
Results: Results from the CAS and DASS-21 questionnaires showed that consumption of chocolate containing bioactive peptide reduced anxiety and stress (p < 0.05). Salivary cortisol measurement showed more than 30% reduction in cortisol level in the intervention group. The peptide had a 95% recovery rate and also demonstrated  thermal and mechanical stability during the production process.
Conclusion: Findings confirmed the undenatured structure of the αs1-casein peptide in chocolate and its resistance to the chocolate processing condition.

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IssueVol 4, No 2 (Spring 2018) QRcode
SectionOriginal Article(s)
Bioactive peptide Sugar-free chocolate Stress salivary cortisol

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How to Cite
Yeganehzad S, Pahlevanloo A, Kiumarsi M, Zayerzadeh A, Sadjadi S-A, Shahidi M, Nadali N. Effects of sugar-free, αs1-casein–enriched chocolate on stress: based on salivary cortisol measurement and questionnaire data collection. J Nutr Sci & Diet. 2018;4(2).