Banca de DEFESA: JÉSSICA DE JESUS DOS SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JÉSSICA DE JESUS DOS SANTOS
DATE: 27/07/2023
TIME: 09:00
LOCAL: Auditório do Departamento de Química
TITLE:

DETECTION OF β-SITOSTEROL BY HPLC-UV TO IDENTIFY ADULTERATION BY ADDITION OF VEGETABLE FAT IN
BUTTER, MILK CREAM AND CHEESE

KEY WORDS:

milkfat’s adulteration; butter; creamy cheese; milk cream; HPLC-UV.

PAGES: 74
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Analítica
SPECIALTY: Métodos Óticos de Análise
SUMMARY:

Milkfat is a bovine milk’s component presents in dairy products that has
economic and nutritional importance, because it is a source of nutrients such as fatsoluble
vitamins and carotenoids. The noblest fraction of milk, it is a source of fat very
valuable that has been target of adulteration by some producers to reduce their costs
and maximize profits. According to the literature, due to availability and low cost, soy
and palm oils have been used as partial or total substitutes for milkfat. The addition of
a substance not declared on the label and/or not permitted by current legislation
constitutes a practice of food fraud. Cholesterol accounts for 95% of the total sterols
present in milkfat. As β-sitosterol is the sterol of vegetable origin found in greater
abundance in vegetable fats, it has the potential to be used as a marker of the presence
of vegetable fat in products of animal origin. The present work aims to describe a
qualitative method capable of identifying the addition of vegetable fat in the milkfat of
butter, creamy cheese and UHT milk cream sold in supermarkets, based on the
analysis of the unsaponifiable matter, by detection of β-sistosterol as a marker of
vegetable fat, using the HPLC-UV technique. The present work results a validated
method for the detection of vegetable fat in butter, milk cream and creamy cheese,
according to the guidelines of the Analytical Quality Assurance Manual: Areas of
Identity and Quality of Food and Inputs, publication of the Brazilian Ministry of
Agriculture and Livestock. The method evaluated in this work met the defined
validation parameters of selectivity, detection limit, repeatability and intermediate
precision. Samples of butter, UHT milk cream and creamy cheese from different brands
were acquired for analysis, from which two brands of butter and one brand of UHT milk
cream adulterated with vegetable fat were identified.

COMMITTEE MEMBERS:
Presidente - ANDRE FERNANDO LAVORANTE
Interno - MARCILIO MARTINS DE MORAES
Externa à Instituição - NATTANY TAYANY GOMES DE PAULA - UFPE