Читать книгу Dry Beans and Pulses Production, Processing, and Nutrition - Группа авторов - Страница 93

Beans are subject to losses during preharvest and postharvest stages. Globally, postharvest quality losses of dry beans are extensive and dramatically impact acceptability of use particularly by increasing the time and energy requirements for preparation and decreases in palatability and nutrient bioavailability (Jones 1999). In the United States, crop losses from birds and mammals during crop growth are limited (around 1%) (May 1977). However, postharvest losses are substantial, with overall losses of stored food due to insects, rodents and microorganisms estimated at approximately 9% (Uebersax and Siddiq 2012).

A general estimate of postharvest losses ranges from 9% in the United States to 40–50% in some developing nations (Pimentel 1976). It has been indicated that pest populations consume or destroy nearly one‐third to one‐half of the world food supply. The quantitative losses of world grain legumes during storage demonstrate wide ranges (up to > 60% in selected cases), primarily attributed to insects (e.g., bruchids), rodents, microbiological spoilage (primarily molds) and physiological deterioration/breakdown (Anon. 1978). It is clearly recognized that harmful microorganisms, insects, and extraneous contamination agents can cause health hazards in food (Testin and Vergano 1990). The use of appropriate packaging is essential for reducing postharvest losses and serves the vital role in storage, distribution, and marketing.

Table 4.1. Compounds associated with off‐flavor in dry beans/ pulses during transit and storage.

Compound	Origin/source	Cross‐contamination and effect
2,4,6‐Trichloroanisole (TCA)	A fungicide, present in minute amounts in paper packaging.	Shipping containers and vessels; flavors/odors (described as medicinal or as a phenolic taint) in wines, coffee, and beans.
2‐methylisoborneol (MIB) and Geosmin	Microbial metabolites produced under anaerobic conditions, e.g., by Actinomyces bacteria.	Shipping containers and vessels; minute amounts (~1 ppb geosmin and ~15 ppm MIB) can cause earthy or musty off‐flavor in dry beans.
Chlorophenols	Produced during chlorine bleaching to sterilize/bleach wood/paper products from reaction of hypochlorite with lignin.	Shipping pallets; Rio off‐flavor in coffee, mild off‐flavor in dry beans.

Source: Buttery et al. (1976); Swanson and Hernandez (1984); Chambers IV et al. (1998); Iamanaka et al. (2014); Slabizki et al. (2016).