Besides increasing shelf life of fluid milk, milk powder has physical and functional properties that allow it to be used as ingredient. The rehydration process is complex and happens in four steps: wettability, sinkability, dispersibility and solubility. Works have been conducted aiming at the development of an easier, more convenient and reproducible method to evaluate the dissolution properties of dairy powders. Therefore, the aim of this work was to evaluate dispersibility and solubility through particle size distribution in order to establish a new rehydration index for whole milk powder. The particle size distribution and morphological characteristics of seven samples of milk powder (from A to G) were analyzed. Samples F and C differed from the others which formed a similar group. Principal component analysis divided the samples into three different groups, allowing the indication of an efficient rehydration index to determine the powders dispersability.

Abstract An analysis of nine sweetened condensed milk brands allowed for the identification of statistically significant difference in moisture, water activity (aw), soluble solids, percentage of protein, lactose crystals size, viscosity and in sensorial attributes of texture, characteristic flavor and flour texture. Relevant correlations between the composition and sensorial attributes were determined. Eighty percent of the samples presented of yeast from <0.6 logCFU.g-1 to 4.7 logCFU.g-1 and seventy percent presented of coagulase-negative staphylococcus from <3.1 log CFU.g-1 to 5.7 log CFU.g-1. These results attest the demand for more controls and investments to provide the market with a safe and standardized product.

O consumo de pizzas prontas aumentou nos últimos anos dado à praticidade do produto e ao baixo custo, sabor agradável e valor nutritivo. Porém, esse produto sofre intensa manipulação durante o seu processamento, contribuindo para sua contaminação, diminuindo a qualidade e aumentando os riscos de doenças veiculadas por esse alimento. Aliado à necessidade de produtos práticos e convenientes, o consumidor demanda alimentos cada vez mais seguros, despertando o interesse pelo uso de conservantes naturais. Dentre eles, o óleo essencial de orégano apresenta ação antimicrobiana, sendo essa especiaria utilizada na culinária de vários países. O objetivo deste trabalho foi o desenvolvimento de filme de base celulósica, incorporado com óleo essencial de orégano para conservação de pizza pronta refrigerada. Esse óleo incorporado ao filme nas concentrações de 25 e 50% p/p apresentou efeito inibitório in vitro para Penicillium spp. e Staphylococcus aureus. Quando aplicado em pizza observou-se diminuição dos compostos ρ-cimeno e γ-terpineno e consequente aumento da concentração de timol e carvacrol, mas provavelmente em quantidade insuficiente para o efeito inibitório dos microrganismos. Com relação à resistência mecânica, os filmes incorporados com 25 e 50% de óleo tiveram sua resistência diminuída, tendo a tenacidade do filme de 50% aumentada com relação ao controle (0%). O uso de filme incorporado com o óleo de orégano desperta grande interesse na aplicação em pizzas, uma vez que o orégano já é um ingrediente do produto, portanto não compromete o sabor e odor da pizza.

The consumption of ready-to-eat pizzas has increased in the last years because of the handiness of the product, its low cost, good flavour and nutritional value. However, ready-to-eat pizzas undergo intense manipulation during processing, contributing to spoilage, reducing the quality and increasing the risks of contamination by pathogens. Besides convenient products, consumers also seek for safer foods, with increasing demand for the use of natural compounds as food preservatives. Among them, the oregano essential oil presents antimicrobial activity and it is a spice used in the cookery of several countries. The objective of this work was to develop a cellulosic film incorporated with oregano essential oil for the conservation of refrigerated ready-to-eat pizza. The oregano essential oil incorporated to the film, in the concentrations of 25% and 50% w/w, showed in vitro inhibitory effect against Penicillium spp., and Staphylococcus aureus. When the oil was applied to the pizza, it caused a decrease in the compounds ñ-cymene and ã-terpinene and a consequent increase in tymol and carvacrol concentrations; however, in an amount probably not enough for the inhibitory effect against microorganisms. The mechanical resistance of the films incorporated with 25% and 50% of oregano essential oil was reduced, and film tenacity increased by 50% compared with the control (0%). The use of films incorporated with oregano essential oil for pizza packaging is of great interest, since the oregano is already an ingredient of the product and therefore it does not compromise the flavour and aroma of the product.