Screening of tomato purée for excessive mould content by near infrared spectroscopy: A preliminary evaluation

Abstract

Abstract Preliminary experiments demonstrated that near infrared spectroscopy (n. i. r.s.) could be used to measure the amount of mould (Botrytis cinerea or Alternaria tenuissima) added to fresh tomato homogenate. In subsequent work, fresh tomatoes that had been allowed to become mouldy were used to prepare a series of tomato purées containing known quantities of mouldy fruit. N.i.r.s. of the freeze‐dried purée was again successful in estimating the amount of contamination as per cent mouldy fruit. Regression analysis selected wavelengths which could be associated with absorption bands of chitin, the major carbohydrate in the cell walls of moulds. It may therefore be possible to utilise n.i.r.s. as a screen for mould in tomato purées if the present success with B. cinerea and A. tenuissima can be extended to the complete range of moulds encountered in tomato products.