Oat bran fortified raspberry probiotic dairy drinks: Physicochemical, textural, microbiologic properties, in vitro bioaccessibility of antioxidants and polyphenols

Lactic acid bacteria viability in different refrigerated food matrices: a systematic review and Meta‑analysis

The aim of this systematic review and meta-analysis was to determine which variables affect the viability of lactic acid bacteria (LAB) added to different types of refrigerated foods during the first 28 days. Scopus, ScienceDirect, PubMed and Cochrane Central Register of Reviews databases were searched from 1997 to April 2022. A total of 278 studies, which showed randomized and controlled experiments published in peer reviewed journals, were included. The viability of LAB in different moments during the storage process was synthesized as mean point estimate (MPE) via random-effects meta-analyses and the effect of multiple factors on the LAB´s viability was evaluated by multiple meta-regression. The meta-analysis showed that the decrease in LAB viability will be more abrupt the greater the initial dose. The physical structure of food may influence bacterial viability. Fruit was the type of product that most quickly lost viability. Co-culture of two or more species did not affect viability. Preservation methods had an unfavorable effect and prebiotics had a beneficial effect on bacterial viability. Viability was genus dependent. The data obtained in this study provide an overview of the factors to be taken into account for the design of new foods.

Effect of inulin and oat flour on viability of probiotics and physicochemical properties of reduced fat synbiotic ice cream

Purpose

The purpose of this study is to investigate the viability of probiotics, physicochemical and sensory properties of reduced fat synbiotic ice cream.

Design/methodology/approach

The treatments were as follows: control was made by the addition of Lactobacillus salivarius NBIMCC 1589 and Lactobacillus crispatus NBIMCC 2451 (1:1). The treatments (T1, T2 and T3) were made with the addition of L. salivarius NBIMCC 1589 and L. crispatus NBIMCC 2451 (1:1) + 2% oat flour, 2% inulin and 4% oat flour + inulin (1:1). Physiochemical parameters (pH, moisture, fat, protein, fibre, ash, overrun, first dripping time and melting rate) were determined.

Findings

The ice cream with inulin and oat flour had lower moisture content, which was recorded 70.41, 69.88 and 68.82% for T1, T2 and T3, respectively. While the protein, fat and ash content of treated samples increased. The highest acidity (0.43%) was recorded in T3. The overrun increased by around 43% in T3 compared with control. The viable counts of probiotics were significantly (p = 0.05) decreased by two or three log cycles. Finally, T3 received the highest sensory score, which could be due to the combination between oat flour and inulin.

Originality/value

A novel ice cream was produced using a combination of inulin and oat flour, which enhanced the viability of added probiotics. Reduced fat synbiotic ice cream was a good carrier for probiotics, which facilitates the production of healthy dairy products.

Natural Polyphenols for the Preservation of Meat and Dairy Products

Food spoilage makes foods undesirable and unacceptable for human use. The preservation of food is essential for human survival, and different techniques were initially used to limit the growth of spoiling microbes, e.g., drying, heating, salting, or fermentation. Water activity, temperature, redox potential, preservatives, and competitive microorganisms are the most important approaches used in the preservation of food products. Preservative agents are generally classified into antimicrobial, antioxidant, and anti-browning agents. On the other hand, artificial preservatives (sorbate, sulfite, or nitrite) may cause serious health hazards such as hypersensitivity, asthma, neurological damage, hyperactivity, and cancer. Thus, consumers prefer natural food preservatives to synthetic ones, as they are considered safer. Polyphenols have potential uses as biopreservatives in the food industry, because their antimicrobial and antioxidant activities can increase the storage life of food products. The antioxidant capacity of polyphenols is mainly due to the inhibition of free radical formation. Moreover, the antimicrobial activity of plants and herbs is mainly attributed to the presence of phenolic compounds. Thus, incorporation of botanical extracts rich in polyphenols in perishable foods can be considered since no pure polyphenolic compounds are authorized as food preservatives. However, individual polyphenols can be screened in this regard. In conclusion, this review highlights the use of phenolic compounds or botanical extracts rich in polyphenols as preservative agents with special reference to meat and dairy products.