Setting a protocol for hazelnut roasting using sensory and colorimetric analysis: Influence of the roasting temperature on the hazelnut quality Tonda Gentile delle Langhe cv.

Abstract

Donno D., Beccaro G.L., Mellano M.G., Di Prima S., Cavicchioli M., Cerutti A.K., Bounous G. (2013): Setting a protocol for hazelnut roasting using sensory and colorimetric analysis: Influence of the roasting temperature on the quality Tonda Gentile delle Langhe cv. hazelnut. Czech J. Food Sci., 31: 390-400.The influence of roasting temperature on the final quality of Piedmont hazelnut (cultivar Tonda Gentile delle Langhe) was evaluated. Sensory and colorimetric analyses were performed to define a quality profile of the fruit relating to the roasting technique parameters. Sensory analysis was conducted on roasted kernels through a trained panel. The effects of the different temperatures on colour were evaluated with two different techniques, colorimeter and scanmarker (scanner), in order to define the best method to individuate correlations between roasting temperature and colorimetric results. The quality traits of nuts roasted at different temperatures were compared: the samples roasted at lower temperature showed lighter colour; the hue values were higher in the roasted chopped nuts, while the chroma was higher in the paste samples. For both paste and chopped kernels a larger range of values was found in comparison with the results given by the colorimeter. As for the sensory analysis, we found that "hazelnut odour" varied significantly among the samples: this descriptor is able to significantly differentiate between different samples. Our study showed that the modulation temperature is a very important parameter with a strong influence on the characteristic roasted flavour and colour of the product.Keywords: qualitative assessment; hazelnut paste; chopped kernels; colorimeter; panel testThe main purpose of roasting is to improve the flavour, the colour, and the crispy and crunchy texture of the product.The roasting process is very important to determine the characteristic roasted flavour and colour of the product: in particular, temperature modulation is an important independent variable significantly affecting the quality features of hazelnuts.This study was performed in order to determine the effect of roasting temperature modulation on the main quality attributes of roasted hazelnuts, in particular colour and final consumer perception.Hazelnuts are the kernels of the hazelnut (Corylus spp.) tree. All the different species of hazelnut trees produce edible nuts, but the common hazelnut (Corylus avellana) is the most extensively grown. Hazelnuts are one of the most nutritious nuts, with a protein content of about 12%. They are also a good source of energy, with a fat content of about 60%, and an excellent source of carbohydrates, half of which are dietary fibre. Hazelnuts also contain

Assessment of the Hazelnuts Roasting Process by Pressure Differential Scanning Calorimetry and MID-FT-IR Spectroscopy

“…Hazelnuts (Corylus avellana L.) which have a unique and unrivalled flavour are used as an additive in a variety of food products, such as, confectionary, chocolate, biscuits, both in a raw and roasted form (Donno et al 2013;Demir and Cronin 2005). Due to the complete dehydration (CiemniewskaŻytkiewicz et al 2014a;Perren and Escher 1997) which induces their specific organoleptic properties, such as, taste and crunchiness, hazelnuts are generally preferred roasted (Demir and Cronin 2005).…”

Experimental characterization and numerical modeling of the compressive mechanical behavior of hazelnut kernels

“…For roasting process, about 2 kg hazelnuts were put in oven at 140°C of temperature during 30 min (Donno et al, 2013). Moisture content of roasted hazelnuts, at the time of analysis, was 2.40% ± 0.31% w.b.…”

Effect of Climate and Roasting on Polyphenols and Tocopherols in the Kernels and Skin of Six Hazelnut Cultivars (Corylus avellana L.)

“…The processing of hazelnuts, especially roasting, causes changes in the content of phenolic compounds as well as antioxidant activity. Roasting plays the main role in hazelnut processing, leading to the improvement of the flavor, color, appearance, and crispiness of the nuts [13]. Hazelnuts are also roasted to remove their skin, which presents a bitter taste after roasting and lowers their value.…”