Quality evaluation of frozen guava and yellow passion fruit pulps by NIR spectroscopy and chemometrics

Priscila D Alamar; Elem T S Caramês; Ronei J Poppi; Juliana A L Pallone

doi:10.1016/j.foodres.2016.04.027

Quality evaluation of frozen guava and yellow passion fruit pulps by NIR spectroscopy and chemometrics

Food Res Int. 2016 Jul:85:209-214. doi: 10.1016/j.foodres.2016.04.027. Epub 2016 Apr 30.

Authors

Priscila D Alamar¹, Elem T S Caramês², Ronei J Poppi³, Juliana A L Pallone²

Affiliations

¹ Department of Food Science, School of Food Engineering, University of Campinas, Monteiro Lobato Street, 80, 13083-862, Campinas, São Paulo, Brazil. Electronic address: priscilaalamar@gmail.com.
² Department of Food Science, School of Food Engineering, University of Campinas, Monteiro Lobato Street, 80, 13083-862, Campinas, São Paulo, Brazil.
³ Institute of Chemistry, University of Campinas, 13083-970, Campinas, S.P, Brazil.

PMID: 29544837
DOI: 10.1016/j.foodres.2016.04.027

Abstract

The present study investigated the application of near infrared spectroscopy as a green, quick, and efficient alternative to analytical methods currently used to evaluate the quality (moisture, total sugars, acidity, soluble solids, pH and ascorbic acid) of frozen guava and passion fruit pulps. Fifty samples were analyzed by near infrared spectroscopy (NIR) and reference methods. Partial least square regression (PLSR) was used to develop calibration models to relate the NIR spectra and the reference values. Reference methods indicated adulteration by water addition in 58% of guava pulp samples and 44% of yellow passion fruit pulp samples. The PLS models produced lower values of root mean squares error of calibration (RMSEC), root mean squares error of prediction (RMSEP), and coefficient of determination above 0.7. Moisture and total sugars presented the best calibration models (RMSEP of 0.240 and 0.269, respectively, for guava pulp; RMSEP of 0.401 and 0.413, respectively, for passion fruit pulp) which enables the application of these models to determine adulteration in guava and yellow passion fruit pulp by water or sugar addition. The models constructed for calibration of quality parameters of frozen fruit pulps in this study indicate that NIR spectroscopy coupled with the multivariate calibration technique could be applied to determine the quality of guava and yellow passion fruit pulp.

Keywords: Chemometrics; Frozen pulps; NIR spectroscopy; PLS regression; Water adulteration.