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Films of chitosan and chitosan-oligosaccharide neutralized and thermally treated: Effects on its antibacterial and other activities, LWT -Food Science and Technology (2016), doi: 10.1016/j.lwt.2016 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT ABSTRACT: 16The present study focuses on the effects of heat and neutralization treatments on 17 solubility, water vapour permeability and antimicrobial activity of chitosan (Ch) and 18 chitosan/chitooligosaccharide (ChO)-based films. ChO films showed stronger 19 antimicrobial activity against Escherichia coli, Bacillus cereus, Staphylococcus aureus, 20 Serratia liquefaciens and Lactobacillus plantarum than Ch films, indicating that this 21effect is attributed to the presence of chitooligosaccharides (COS) in the films. Heat 22 and neutralization treatments decreased significantly the solubility of chitosan films and 23 gave rise to a sharp loss in their antimicrobial activity. The incorporation of COS in 24 chitosan films increased the inhibitory effect against the studied microorganisms 25 without affecting significantly the water vapour permeability of the films. Thus, it is 26 possible to get a more insoluble chitosan film with high antimicrobial activity by means 27 of incorporation of COS combined with heat or neutralization treatments.

The ability of several oenological fining agents to remove ochratoxin A (OTA) from red wine was studied. The adsorbents tested were activated sodium bentonite, egg albumin, allergen-free adsorbents (complex PVPP, plant protein and amorphous silica (complex) and high molecular weight gelatine), and the non-toxic biodegradable polymers (chitin and chitosan). Several dosages within the oenological use range were tested and the wine pH, colour parameters and polyphenol concentration impact associated with each fining agent were studied. Generally, OTA removal achieved in all treatments was higher when the adsorbent dosage increased, but the impact on wine quality also was higher. Chitin at 50 g hl(-1) removed 18% the OTA without affecting significantly the wine-quality parameters. At the highest dosage tested the gelatine and complex treatments achieved greater OTA removal (up to 39-40%) compared with bentonite, egg albumin and chitin. Moreover, the gelatine and the complex had a lower impact on colour parameters and polyphenol concentration compared with chitosan, whilst OTA was reduced to around 40%. Chitosan achieved the greatest OTA removal (67%), but it strongly affected the wine-quality parameters. Otherwise, bentonite showed a relative efficiency to remove OTA, but the CI value decreased considerably. The egg albumin treatment only removed OTA up to 16% and moreover affected strongly the CI value and CIELab parameters. The results of this survey showed that the non-toxic chitin adsorbent and the allergen-free adsorbents tested could be considered as alternative fining agents to reduce OTA in red wine.

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