Scholarly record

USING FREEZE DRYING FEIJOA IN YOGURT TECHNOLOGY

Evgeniy Titov

Abstract

Fruit yogurts are always preferred among dairy products, as they are delicious low-calorie foods associated with healthy nutrition. Now yogurts with tropical fruits are popularity due to their exotic taste and positive influence on human health. The production of yogurt with the addition of feijoa is limited to a short period of storage and selling of this fruit. Vacuum freeze-drying can solved this problem. Therefore, the aim of this research was to determine the rational amount of freeze-dried feijoa for adding to the composition of yogurt. For this, the feijoa fruit was cut into pieces, frozen, and then was subjected to vacuum freeze-drying. After that, the fruit slices were ground up and added to yogurt. Pasteurized cow's milk (milk fat 2.5%, protein 3.5%, TS 11% and pH 6.6-6.7) was used for yogurt production. Sugars and sweeteners did not added to milk. Yogurts are prepared by fermentation of milk with bacterial cultures consisting of Lactobacillus bulgaricus and Streptococcus thermophilus. The production of yogurts was by two ways: set and stirred yogurt. The dry powder of feijoa added to yogurt in two ways. The first way included adding the freeze-dried powder to the normalized mixture prior to pasteurization. The second way - the freeze-dried powder added in the finished product after fermentation. A freeze-dried powder added in an amount of 1 to 10% with step 1%. The acid-producing ability, active and titratable acidity, water holding capacity and sensory evaluation were determined in the yoghurt samples at zero time and during of storage at refrigerator. It was shown that the most rational concentration of addition was in the range from 3 to 5%. The addition of more than 5% of the freeze-dried feijoa resulted in inhibition of the starter microflora in yogurt and significantly influenced the physical-chemical properties and sensory characteristics of the yogurt (taste of yoghurt disappeared, the taste of feijoa intensified) in both cases.

Publication Impact Profile

• Citations
• Scopus - Citation Indexes: 2

• Captures
• Mendeley - Readers: 6

PLUMX see details

DOI resolver: doi.org/10.5593/sgem2018/6.2/s25.104

Publication details

Back to publication list