In this study a laboratory scale conch was developed with the purpose of testing new formulations using small amounts of chocolate mass. The equipment was built with working parts of others machines and the chocolate manufactured with the conch was evaluated in relation to the viscosity, moisture, acidity and polyphenol concentration. The resulting chocolate was tempered and then evaluated by a sensory panel. The results were always compared with an industrial conching process. The material used in the assays was dark chocolate (40% cocoa). Data were submitted to variance analysis (anova) and when there was significant difference among the averages, the Tukey's test was applied. It was verified that the reduction of moisture and viscosity of the mass in the laboratory scale was similar to industrial scale. The parameters acidity and polyphenols showed no significant alterations when comparing both process scales. However, in the sensory analysis a flavour difference between the processing scales was perceptible.

Quinoa (Chenopodium quinoa Willd) is a good source of vitamin E containing high quality protein. A dark chocolate with the addition of 12, 16 or 20% quinoa was developed. The protein concentration of the products increased as the percentage of quinoa increased. The product containing 20% quinoa showed only 9% increase in vitamin E, while the quantity of polyphenols decreased from 23.5 to 18 μmol pirocatechin/g. The amount of essential amino acids was improved in samples containing quinoa. Cysteine, tyrosine and methionine increased by 104, 72, 70%, respectively in chocolate containing 20% quinoa. The amino acid pattern was as per WHO standards, which was adequate to human needs. The chocolate with quinoa was approved by 92% of the sensory panel. All the samples showed an index of acceptance above 70%. Quinoa could be used at the levels evaluated in this study adding its potential health benefi t to the dark chocolate.