Laboratorio Arbitral Agroalimentario. Ministerio de Agricultura, Alimentación y Medio Ambiente, C/Aguarón 13, 28023, Madrid, Spain.
Rapid Commun Mass Spectrom. 2012 Aug 30;26(16):1753-60. doi: 10.1002/rcm.6281.
The cider market is an important sector of the food industry in certain regions. Adulteration of cider can happen in several ways: for example, by the addition of sugar, or of exogenous CO(2) to certain types of cider. Because such practices are not allowed by either Spanish legislation or the legislation of other countries, it is essential to study possible methods to detect these unauthorized practices. For this purpose a procedure was required to study the stable carbon isotopic composition of CO(2) in cider.
A liquid sample of cider was transferred to a vial and CO(2) from the headspace of the vial was analyzed using a peripheral device interfaced to an isotope ratio mass spectrometer. Separation of the CO(2) from water and ethanol was achieved using a gas chromatography column located in the peripheral device.
The values for repeatability and reproducibility obtained indicated the robustness of the method, which is required for routine analysis. Ninety cider samples from various origins were analyzed, most of which showed a (13)C content consistent with the declared origin. The δ(13)C ranged from -24.80‰ to -20.89‰ for ciders with endogenous carbon dioxide (-22.74 ± 0.79‰) and -37.13‰ to -26.00‰ if industrial CO(2) was added. Several samples were also suspected of C4 sugar addition prior to the fermentation.
A fast, accurate and simple method for cider adulteration detection was developed. The addition of exogenous CO(2) as well as C4 sugar addition prior to fermentation could be detected. The method showed advantages over existing methods in term of simplicity (no sample preparation and very long-term stability of the sample), speed (less than 10 min/sample) and precision ((r ≤0.32 and R ≤0.42).
苹果酒市场是某些地区食品工业的一个重要组成部分。苹果酒的掺假可能通过多种方式发生：例如，通过添加糖，或通过向某些类型的苹果酒添加外源性 CO₂。由于西班牙立法或其他国家的立法都不允许这些做法，因此必须研究可能的方法来检测这些未经授权的做法。为此，需要研究 cider 中 CO₂ 的稳定碳同位素组成的程序。
将 cider 的液体样品转移到小瓶中，并使用与同位素质谱仪接口的外围设备分析小瓶顶空的 CO₂。位于外围设备中的气相色谱柱实现了 CO₂与水和乙醇的分离。
所获得的重复性和再现性值表明该方法具有稳健性，这是常规分析所必需的。分析了来自不同来源的 90 个 cider 样品，其中大多数样品的（13）C 值与所宣称的来源一致。内生二氧化碳的 cider 的 δ（13）C 范围为-24.80‰至-20.89‰（-22.74±0.79‰），如果添加工业 CO₂，则为-37.13‰至-26.00‰。几个样品也被怀疑在发酵前添加了 C4 糖。
开发了一种快速、准确和简单的 cider 掺假检测方法。可以检测到添加外源性 CO₂以及发酵前添加 C4 糖。该方法在简单性（无需样品制备且样品稳定性非常长）、速度（每个样品小于 10 分钟）和精密度（（r ≤0.32 和 R ≤0.42）方面优于现有方法。
