Utilization of carob pods in the production of alternative to cocoa powder
Abstract: Roasting process of carob pods at various temperatures for different times was carried out to study the effect of its process on the chemical constituents, minerals, phenolic compounds and antioxidant activities. Volatile compounds were also determined for roasted carob powders. The obtained results revealed that protein content was 5.42% (on dry weight basis), which decreased with increasing the processing temperatures. Whereas, ash increased gradually by increasing the roasted temperatures but lipids was decreased. Results also showed that all minerals could be the same in all treatments. Raw carob pods contain 21.07mg/g of total phenolic compounds. Thermal treatment caused to degradation of polyphenolic compounds which increased with increasing roasted temperatures. Total antioxidant activity for all samples of carob powders determined by 2,2-diphenyl-1-picryl-hydrazyl (DPPH) as free radical scavenging. The results showed that the antioxidant activities of the carob powders were decreased due to roasting process. Total antioxidant activity in raw carob powder was 90.09%, but decreased to 70.28, 65.50; 69.93, 64.53 and 67.05 and 63.82 % after roasted at 150, 160, and 170˚C for 30 and 40 min., respectively. It is clearly evident that losses of polyphenolic compounds and antioxidant activities in all samples increased with increasing roasting time and temperatures. Evaluation of sensory characteristics of both hot drink and cake showed greater preference, which the carob powders roasted at 160˚C for 30 min. and 40min. were given the highest scores compared with other samples as well as control, when used roasted carob powder as alternative of cocoa powder. GC–mass spectrometry was used to identification aroma components and seven compounds were positively identified. The major contribution was that of 3-methyl butanal and methyl propanal (responsible to chocolate flavor). 3-methyl butanal was increased as result of roasted carob powders. Moreover, some volatile compounds were identified in roasted carob and found in dark chocolate such as 2-Heptanone, Pentan-2-ol and Linalool. Other volatile compounds, Nonane-2-one and Hexanal, were identified in roasted carob powders.
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Publication year 2009
Pages 151-159
Organization Name
City Cairo
serial title Arab Univ. J. Agric. Sci., Ain Shams univ
Author(s) from ARC
Publication Type Journal
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