Method for producing fruit and vegetable crisps by combination of vacuum low-temperature frying and vacuum microwave drying

Abstract

The invention relates to a process for producing fruit and vegetable crisps by combination of vacuum low-temperature frying and vacuum microwave drying. The method mainly comprises the following steps of performing selecting, finishing, cleaning, blanching for enzyme deactivation or pretreatment such as precooking, cooling, steeping and quick-freezing on fruit and vegetable raw materials, and concretely comprises the steps: firstly processing the raw materials into a semi-product with a water content of 50%-35% and an oil content of 3%-10% through a vacuum low-temperature frying process, and then drying and dewatering the semi-product through a vacuum microwave drying process, wherein the water content of a finished product is controlled to be below 5%, the oil content is controlled to be below 10%, and the expansion ratio is 1.5-2.0. According to the process, the nutrients and shape of the product are ensured to the greatest extent, the dehydration time can be obviously shortened, the energy consumption is lowered, the cost is reduced, and meanwhile, the oil content of the product can be effectively controlled, so that the process is particularly suitable for application to processing of the fruit and vegetable crisps.

Description

technical field [0001] The invention discloses a method for combining vacuum low-temperature frying and vacuum microwave drying to produce fruit and vegetable crisp snack food, which belongs to the technical field of food processing. Background technique [0002] Atmospheric pressure high-temperature frying method, vacuum low-temperature frying method, vacuum airflow puffing method, and vacuum freeze-drying method are several main methods for processing fruit and vegetable crisps at present. [0003] The normal-pressure high-temperature frying method is suitable for processing a small number of fruit and vegetable raw materials with high starch content. Its main disadvantage is that high temperature will damage the nutrients in fruits and vegetables, and at the same time, it will cause polymerization of unsaturated fatty acids in oils and fats, forming indigestible or toxic Polymers such as dimers, trimers or polymers, etc., their accumulation in the body is harmful to human...

AI Technical Summary

Problems solved by technology

But its main disadvantage is: the fruit and vegetable crisps processed by vacuum low-temperature frying method, when the product is dried in the oil, the drying time is relatively long, generally ranging from 40min to 90min, which directly leads to the high oil content of the product, all in 20 %, some even as high as 40%, which is not in line with the diet concept of modern people; on the other hand, the oil is used too many times and the processing time is too long, which will also produce a small amount of harmful substances in the product, and the expansion rate of this process is only 1.1 ~1.3, high energy consumption

The disadvantage of this invention is that although hot air drying can well retain the original nutrients and color, it is suitable for processing granular food, but it has a large degree of damage to sheet and strip fruit and vegetable raw materials, and also has great damage to heat-sensitive fruit and vegetable materials. Although its products do not contain oil, they taste dry and astringent, without the sweetness and smoothness of oily foods