14A-35 |
Stability of Requeijão cremoso in glass packages with and without exposure to light. |
R. M. V. Alves1, A. G. F. VAN DENDER2, S. B. Jaime1, I. Moreno3, B. C. Pereira1, and M. L. Junquer2. (1) Cetea - Centro de Tecnologia de Embalagens, Instituto de Tecnologia de Alimentos - ITAL, Avenida Brasil, 2880, Campinas - Sao Paulo, 13073-001, Brazil, (2) Centro de Pesquisa e Desenvolvimento de Laticínios - Tecnolat, Instituto de Tecnologia de Alimentos - ITAL, Avenida Brasil, 2880, Campinas - Sao Paulo, 13073-001, Brazil, (3) Instituto de Tecnologia de Alimentos - ITAL, Avenida Brasil, 2880, Campinas - Sao Paulo, 13073-001, Brazil Requeijão cremoso is a genuine Brazilian, smooth textured processed cheese obtained by cooking a blend of fresh cheese curd, emulsifying salts, water and cream. The product is typically marketed in glass packages sealed off with an easy-open closure system which remain exposed to light for varying periods of time in retail cabinets. The objective of this study was to compare the stability of requeijão filled in regular glasses stored at 10±2ºC at three different conditions: in the dark (1) and exposed to light (1000 lux) in both the normal upright position (2) and turned upside down (3). The product was hot-filled (75 to 85ºC) in a way such as to guarantee that the internal vacuum level after cooling remained constant at 17-18polHg. The total headspace gas volume was about 4mL (at 25ºC; 0,94 atm) and the packages contained on average 248g of requeijão. The physical-chemical (pH=5.78, EST=35.44% and GES=60.48%) and microbiological (psychrotrophic and mesophylic <10 UFC/g, total and fecal coliforms <3NMP/g and moulds and yeasts < 10 UFC/g) characteristics of the product were evaluated after 1 day storage and the results complied with current legislation. Throughout storage, the oxygen level in the headspace was determined by gas chromatography whereas the sensory attributes of the product were assessed by 15 panelists. Throughout 90 days in the dark (1), the oxygen level in the headspace remained unaltered (19-20%) whereas in the packages exposed to light it was reduced to 6% and 2% after 60 days in (2) and (3), respectively. The product stored in the dark did not exhibit any change in sensory attributes, whereas the product exposed to light exhibited a loss of characteristic taste and the development of rancid taste which caused the rejection of the product after 50 days. Rancid taste developed mainly in the surface area in contact with the headspace and was statistically not more intense than that in the cups with a larger light exposure area.
Session 14A, Dairy Foods: General developments in dairy technology I
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