Influence of Preparation and Processing on Cranberry Gel Properties
Abstract (Summary)Four formulations of cranberry gels using raw materials manufactured by a variety of different processes were examined for their rheological and textural properties. Generally, with higher treatment temperature and holding times, the gels' rheological and textural properties improved. Gels were examined 24 hours, 48 hours, and 4 days after being prepared. Gels generally showed some further improvement of gel strength during the storage, particularly for gels that were initially processed for the shortest time at the lowest temperature.The pectin molecular properties of five different types of raw cranberry purees were examined for the effect of processing conditions. Pectin was extracted from each type of puree, yield determined and FT-IR analysis was performed in order to determine degree of esterification of each type of extracted pectin. Degree of esterification ranged from ~60-90%. Puree from fresh fruit and cranberry puree concentrate had the highest yield and degree of esterification, whereas purees from the byproducts of puree processing had lower yields and degree of esterification. Purees exposed to elevated temperatures and prolonged heating times showed signs of hydrolysis.
School Location:USA - Massachusetts
Source Type:Master's Thesis
Keywords:cranberry pectin rheology food science
Date of Publication:01/01/2007