Sulforaphane formation and bioaccessibility are more affected by steaming time than meal composition during in vitro digestion of broccoli. (1st January 2017)

• Record Type: Journal Article
• Authors: Sarvan, I.; Kramer, E.; Bouwmeester, H.; Dekker, M.; Verkerk, R.
• Is Part Of: Food chemistry. Volume 214(2017)
• Page Start: 580
• Page End: 586
• Publication Date: 2017-01-01
• Subjects: Glucoraphanin -- Myrosinase -- Processing -- Enzymatic hydrolysis; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2016.07.111
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Differently prepared broccoli meals during in vitro digestion (not colonic) studied. Endogenous glucoraphanin hydrolysis occurs during digestion mainly in oral phase. Meal additives did not change the in vitro bioaccessibility of sulforaphane. Raw/1-min steamed broccoli showed highest sulforaphane formation after digestion. Endogenous myrosinase was inactivated in the in vitro gastric phase irreversibly. Abstract: Broccoli is a rich source of the glucosinolate glucoraphanin (GR). After hydrolysis of GR by the endogenous enzyme myrosinase, sulforaphane (SF) or sulforaphane nitrile (SFN) are produced, depending on environmental conditions. How the conversion of GR and bioaccessibility of released breakdown products are affected by steaming (raw, 1 min, 2 min and 3 min steamed) and meal composition (protein or lipid addition) was studied with an in vitro digestion model (mouth, stomach, intestine, but not colonic digestion). The main formation of SF and SFN occurred during in vitro chewing. The contents of GR, SF and SFN did not change after further digestion, as the irreversible inactivated myrosinase under gastric conditions caused no further GR hydrolysis. SF concentrations were up to 10 times higher in raw and 1 min steamed broccoli samples after digestion compared to longer-steamed broccoli. Protein or lipid addition had no influence on the formation and bioaccessibility of SF or SFN.