Effect Of Fermented And Roasted On The Quality Of Cocoa Beans And The Study Of Cocoa Of Jam

Cocoa is one of the world’s three largest soft drinks, it has a high nutritional value, widy used in chocolate, drinks, cakes, ice cream and other food industry. The requirement of cocoa has increased every year in the Chinese market. Cocoa mainly grown in tropical regions, Hainan province accounts for about 90% of china’s cultivated area. The main processing of cocoa beans is based on deep processing in China. And almost all of initial processing products come from imports. So it isn’t conducive to the development of domestic cocoa processing.The initial processing of cocoa bean of the main process formed its unique flavor, and it is also the important process to determine the quality of cocoa bean. The identify of quality of cocoa beans is rough and fuzzy in foreign countries. In addition, the polyphenol content of cocoa beans were significantly reduced. In order to provide theoretical basis of development and identify of cocoa beans, this paper studied the effect of fermented and roasted on polyphenols, flavonoid and volatile components of cocoa beans, and the quality of cocoa beans of different treatments were identified by electronic sensory followed by the artificial evaluation method. Moreover, a rich source of polyphenols jam was initially produced, and its optimal proportion and the rheological properties of jam.The cocoa beans of different treatments in the total amount of polyphenols and flavonoids were detected by UV spectrophotometry, and combined with HPLC analysis of changes in gallic acid, catechin, epicatechin, anthocyanin content. The results show that the total polyphenol and flavonoid content of unroasted unfermented cocoa beans were significantly higher than that of unroasted fermented cocoa beans. At 105-145℃ by roasting for 30 min, the total polyphenol were ranged from 419.5 to 129.8 mg/10g in unfermented cocoa beans and ranged from 182.4 to 85.6 mg/10g in fermented cocoa beans. Total flavonoids were found to be between 77.8 and 16.8 mg/lOg for unfermented cocoa beans, and between 34.7 and 7 mg/10g for fermented cocoa beans. At 125℃ by roasting for 20-40 min, the total polyphenol were ranged from 353.74 to 289.45 mg/lOg in unfermented cocoa beans and ranged from 152.08 to 123.55 mg/lOg in fermented cocoa beans. Total flavonoids were found to be between 42.86 mg/lOg and 32.20 mg/lOg for unfermented cocoa beans, and between 25.12 and 21.14 mg/10g for fermented cocoa beans. The contents of gallic acid, catechin, epicatechin, anthocyanin were reduced. The contents of gallic acid, catechin, epicatechin, anthocyanin in unroasted of unfermented and fermented cocoa beans were 1.97 mg/g,28.46 mg/g,36.01 mg/g,10.03 mg/g and 0.16 mg/g、17.36 mg/g、27.85 mg/g、7.88 mg/g. At 135-145℃ by roasting for 30 min, the contents of four monomers substance were large reduction. At 125℃ by roasting for 20-40 min, the contents of four monomers substance were small changes.And then The solid phase microextraction (SPME)-gas chromatography-mass spectrometry (GC-MS) was used to investigate the volatile components of cocoa beans of unfermented, fermented and roasted cocoa beans, and the principal component analysis method was combined to analyze the difference. The results showed that the volatile components of the unfermented, fermented and roasted beans were significantly different, and 30 and 62 kinds of volatile components were identified from the fisrt two samples, mainly alcohols, ketones, olefins and aldehydes. It can be concluded that the aromas of unfermented and fermented bean were significantly different. Roasted at the temperature of 105℃,125℃ and 145℃,47,59,84 and 71,68,83 volatile components were respectively determined from unfermented and fermented beans, mainly alcohols, esters, aldehydes, alkenes and pyrazine. Fermentation enhanced the volatile components quantity, and the significant difference existed in the volatile components concentration between the cocoa beans roasted at low and high temperature. Ketenes were focused on unfermentation cocoa beans of under low temperature. Acids, esters and alcohols tend to fermentation cocoa beans under low temperature. And Furans, pyrazines and other heterocyclic compounds were pointed to the high temperature part. The difference of these volatile components resulted in the flavor difference of specific treatments cocoa beans. Therefore, principal component analysis has the potential to be used for aroma quality evaluation of the cocoa beans from different treatments.Finally, In the current work, the quality of cocoa beans of unfermented, fermented, roasted unfermented and roasted fermented cocoa beans were investigated by electronic nose, colorimeter and moisture meter. The artificial evaluation method and principal component analysis were combined to analyze the difference of flavor. The cocoa beans from different treatments presented a large difference by electronic sensory analysis. The moisture content of unfermented cocoa beans was higher than that of fermented cocoa beans. At 115-145℃ by roasting for 30 min and at 125℃ by roasting for 20-40 min, the total fat were on the rise. Roasted at the different temperature, the chroma value of unfermented cocoa beans is relatively decentralized, and fermented cocoa beans is relatively concentrate. Unfermented, fermented and roasted cocoa beans were divided into low and high temperature area by the artificial evaluation method combined with principal component analysis. The quality of cocoa beans were distinguished by analysis of the correlation between variables and the dependent variable. The study demonstrates that the quality of cocoa beans of different treatments can be effective identified by electronic sensory followed by the artificial evaluation method.Effect of fermented and roasted on polyphenols and flavonoid of cocoa beans were significantly. And the fresh fruit of cocoa can fulfil the maximum retention of active substrate, so the rich polyphenols of jam were developed by using fruit. Through sensory score, the optimal proportion of pulpa, sugar, cocoa powder was determined. Under the best proportion condition studied the effect on rheological properties, taste, and viscosity of jam the grinding mode was determined. Then by studying the changes of pH, exterior, flavor and rot time of sterilization conditions jam was identified. The optimal condition of the cocoa jam beverage was as follows:roasting the fermented cocoa beans 30 minutes under 125℃; the cocoa of pulpa:sugar:natural cocoa powder is 6:12:1; automatic grinding mode; sterilization temperature 121℃, sterilization time 15 minutes.