Auteurs : Fadi Ali, Jessica Houde, Carmen Charron, Mustapha Sadiki
Cet article est disponible seulement en anglais (Food Control, Vol. 123, May 2021, 107728). Le numéro de référence (Digital Object Identifier (DOI)) est le : 10.1016/2020.107728.
Abstract
Nanofiltration and Reverse Osmosis are membrane concentration processes originally used by maple syrup producers to preconcentrate the sap to a moderate °Brix level (8–16 °Brix). The purpose of this study is to evaluate the potential of new membrane technology to concentrate maple sap to ultra-high °Brix and to investigate the effect of this concentration on the chemical composition and physical properties of final sap concentrate. Maple sap was concentrated up to 42 °Brix using two industrial membrane units. The contents of main solutes increased with the °Brix of concentrates depending on the specific rejection rate of the membranes tested. A slight and significant decrease was observed in the availability of some solutes such as K+, Mn++ and polyphenols in ultra-high-concentrated sap. However, the apparent organoleptic and physical properties of these concentrates have not been altered. According to the results of this, the new membrane process allows to produce ultra-high °Brix concentrate of maple sap with interesting properties. However, further works have to be performed on this technology to more precisely determine the highest °Brix level that will minimise the affect on chemical composition and properties of concentrated sap and the corresponding maple syrup. (4010119)
Auteurs : Mariane Camara, Mélissa Cournoyer, Mustapha Sadiki, Nathalie Martin
Cet article est disponible seulement en anglais (Journal of Food Science, Vol. 84, Iss. 6, 2019). Le numéro de référence (Digital Object Identifier (DOI)) est le : 10.1111/1750-3841.14618.
Abstract
Buddy maple syrup is characterized by an unpleasant cabbage‐like flavor occurring generally toward the end of the sap harvest season. Occurrence of buddy off‐flavor leads to a decrease in syrup value and economic loss for the industry. It is therefore relevant to characterize the off‐flavor in order to apply corrective treatments. HS‐SPME combined with GC/MS was applied to analyze volatile aroma compounds in buddy maple syrup samples. Two novel volatile sulfur compounds were found in maple syrup: dimethyl disulfide (DMDS) and dimethyl trisulfide. A 3‐alternative forced choice in ascending concentration of different buddy syrups diluted in good quality syrup was conducted in triplicate to assess buddy syrup concentration thresholds leading to detection and recognition of the off‐flavor by 16 panelists while monitoring volatile aroma compounds in diluted samples. Results showed that DMDS was associated with the flavor defect. The recognition threshold concentration of buddy syrup varies depending on the syrup sample and the off‐flavor can be detected in syrups containing very low DMDS content. Application of a continuous heat treatment on buddy syrups for 2 hr at 104.5 °C led to a removal of the buddy off‐flavor as well as a significant reduction in DMDS content. (4010114)
Pratical Application
The results of this study provide a better understanding of the buddy off‐flavor in maple syrup and the heat treatment applied allowed us to eliminate this defect and obtain a syrup with a better sensory quality.
Auteurs : Luc Lagacé, Mariane Camara, Nathalie Martin, Fadi Ali, Jessica Houde, Stéphane Corriveau et Mustapha Sadiki
Cet article est disponible seulement en anglais (Heliyon, volume 5, Issue 6, June 2019, Article e01786).
Background
Techniques used to produce maple syrup have considerably evolved over the last decades making them more efficient and economically profitable. However, these advances must respect composition and quality standards as well as authenticity of maple products. Recently, a new and improved high vacuum technology has been made available to producers to achieve higher sap yields. The aim of the present study was therefore to evaluate the effect of this new system on the yield of sap and on the sap and syrup chemical composition.
Results
Sap yield was monitored during the 2013 and 2014 seasons for high vacuum collection systems (25–28 InHg) and compared to the control systems (20 InHg). Samples of sap and syrup were also collected for chemical analysis. During the 2013 season, a sap volume of 166.19 L/tap was recorded at 25 InHg vacuum level while the control vacuum level permitted to collect 139.47 L/tap, corresponding to a yield increase of 19.2 %. The following season, a yield increase of 38.2 % was measured when control and 28 InHg vacuum levels were compared with 118.06 and 163.13 L/tap, respectively. Results on the pH, color, flavor, minerals, sugars, organic acids, total polyphenols, total nitrogen, abscisic acid and auxin (Indol-3-acetic acid) showed no major differences between high vacuum technology and the control with values remaining within ranges previously published.
Conclusion
Results showed that a use of high vacuum systems increased sap yield and had no major impact on the quality and purity of maple sap and syrups compared with the control systems.