Banca de DEFESA: MARIÁ TOLEDO DE CARVALHO SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARIÁ TOLEDO DE CARVALHO SILVA
DATE: 15/09/2023
TIME: 08:00
LOCAL: PPGEA - Instituto de Agronomia, UFRRJ
TITLE:

Development of pH-indicator film from purple fleshed sweet potato (ipomoea batatas (l.) lam) for food quality monitoring

KEY WORDS:

pH indicator films, anthocyanin, food spoilage

PAGES: 96
BIG AREA: Ciências Agrárias
AREA: Ciência e Tecnologia de Alimentos
SUBÁREA: Tecnologia de Alimentos
SPECIALTY: Tecnologia de Produtos de Origem Vegetal
SUMMARY:

The losses and waste that occur along the chain affect food and nutritional security, in
addition to represent significant economic and environmental losses. On the other hand, the
consumption of inappropriate foods can cause diseases and become a risk to public health.
Thus, reducing such losses and, at the same time, ensuring the supply of safe foods with
preserved nutritional and sensory quality is an important challenge for the food industry. For
this, intelligent films capable of monitor the quality of the food and indicate the freshness and
safety of the packaged product have been widely studied. Among them are pH indicator films,
obtained by the association of a pigment sensitive to pH changes and a polymeric base. Thus,
the objective of this work was to develop pH indicator films using purple-fleshed sweet
potatoes to dynamically monitor the quality of the food. The purple-fleshed sweet potato was
cooked and freeze-dried resulting in a uniform and color-stable freeze-dried sweet potato
powder (PLBD). The film was developed using starch with or without the addition of
carboxymethylcellulose (CMC) and different concentrations of PLBD through the casting
method. Both the PLBD and the developed films showed visually noticeable color changes
when submerged in buffer solutions of different pH values, ranging from pink to greenish
tones when the pH increased from 1 to 11. The effectiveness of the indicator films was
evaluated by the test of ground beef spoilage, which resulted in the color changes from purple
to green when meat pH increased from 5.54 to 7.92. The microbiological growth and sensory
changes in the meat confirmed the deterioration process that had occurred. Therefore,
biodegradable pH indicator films have been successfully developed without the use of a
previous anthocyanin extraction step and can be used in the development of intelligent
packaging capable of indicating in real time the quality of the packaged food.

COMMITTEE MEMBERS:
Presidente - 1806986 - ELISA HELENA DA ROCHA FERREIRA
Externo ao Programa - 3103346 - JOAO VICTOR NICOLINI - UFRRJExterna ao Programa - 1148731 - KETLY PONTES SOARES - UFRRJExterno à Instituição - ANDRE FIORAVANTE GUERRA - CEFET/RJ
Externo à Instituição - VERONICA MARIA DE ARAÚJO CALADO