Sunflower Stalk Pith Fibre: Investigation On Oil Holding Capacity, Oil–Fibre Interaction and Related Application In Food

ANNOUNCEMENT
Final Examination for the Degree of MSc
MINGYUE QI

Examining Committee
Dr. Yoshi Mine, Chair
Dr. Douglas Goff, Advisor
Dr. Steve Cui, Advisory Committee Member
Dr. Iris Joye, Department Examiner

TITLE: Sunflower Stalk Pith Fibre: Investigation On Oil Holding Capacity, Oil–Fibre Interaction and Related Application In Food

ABSTRACT: Water holding capacity (WHC) and oil holding capacity (OHC) of ground sunflower pith fibre (SPF) were studied. The oil holding stability of SPF was further investigated, as well as its application in food industry. Both WHC and OHC increased with particle size, reaching up to over 40 g liquid/ g fibre at particle size of 30 mesh (0.595mm). However, the oil-SPF mixtures showed massive oil loss after staying on the filter paper for 24 and 48 hrs, which increased along the time with particle size decrease. The microscopic study showed that both the whole sunflower pith and ground pith powder contain porous structure. The FT-IR analysis indicated that the two main compositions of SPF are cellulose and pectin. From NMR T2 relaxation profiles, all the mixtures of oil and SPF at particle size of 30, 50, 100 and 200 mesh showed stronger oil-SPF interactions with less free oil in the samples. The in-vitro oil digestion was not affected with 4% SPF addition. Showing the best OHC, 30 mesh SPF reduced 74% oil loss in peanut butter with 2.2% addition. These findings could explain the reason of SPF’s high OHC and contribute to new applications for SPF, especially as oil stabilizer.